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Contextual Weisfeiler-Lehman graph kernel for malware detection | Graph-based malware detection using dynamic analysis | AUTOMATED EVALUATION OF ESSAYS AND SHORT ANSWERS | kor_Hang | 4,900 |
A method for watermarking java programs via opaque predicates | Watermarking, Tamper-Proofing, and Obfuscation -- Tools for Software Protection | Sensor networks: evolution, opportunities, and challenges | eng_Latn | 4,901 |
Model-Driven ERP Implementation | Making ERP a Success. | Detecting Obfuscated Viruses Using Cosine Similarity Analysis | kor_Hang | 4,902 |
High-Resolution Side Channels for Untrusted Operating Systems | Innovative Instructions and Software Model for Isolated Execution | Towards Efficient Model for Automatic Text Summarization | eng_Latn | 4,903 |
why binary analysis of software | The BitBlaze project also strives to open new application areas of binary analysis, which provides sound and effective solutions to applications beyond software security and malicious code defense, such as protocol reverse engineering and fingerprint generation. | Fundamental analysis looks at the asset itself and attempts to illustrate a picture of the general health of the asset. For example, if you want to trade stock binary options, you would want to look at the company in question, its profit/loss numbers, future projections, and past progress. | eng_Latn | 4,904 |
what is a heuristic analysis | Heuristic analysis is a method employed by many computer antivirus programs designed to detect previously unknown computer viruses, as well as new variants of viruses already in the wild.nother common method of heuristic analysis is for the anti-virus program to decompile the suspicious program, then analyze the source code contained within. The source code of the suspicious file is compared to the source code of known viruses and virus-like activities. | A heuristic evaluation is a usability inspection method for computer software that helps to identify usability problems in the user interface (UI) design.It specifically involves evaluators examining the interface and judging its compliance with recognized usability principles (the heuristics).euristic evaluations are one of the most informal methods of usability inspection in the field of human-computer interaction. There are many sets of usability design heuristics; they are not mutually exclusive and cover many of the same aspects of user interface design. | eng_Latn | 4,905 |
what is reverse engineering | Oracle Application Testing Suite. Reverse engineering is taking apart an object to see how it works in order to duplicate or enhance the object. The practice, taken from older industries, is now frequently used on computer hardware and software. Software reverse engineering involves reversing a program's machine code (the string of 0s and 1s that are sent to the logic processor) back into the source code that it was written in, using program language statements. Download Our Guide to Agile DevOps. | At times you may find it really difficult to imitate a sound or to understand the way a native speaker is using his mouth. A very powerful technique I stumpled upon is what I call the accent reverse engineering. Observe how a native speaker speaks your own language. Chances are he/she will be speaking with an accent. | eng_Latn | 4,906 |
what are computer forensics tools | Computer Online Forensic Evidence Extractor or COFEE is a tool kit developed for computer forensic experts. This tool was developed by Microsoft to gather evidence from Windows systems. It can be installed on a USB pen drive or external hard disk. | Anti-forensics â Anti-forensics is the practice of attempting to thwart computer forensic analysis. This may include encryption, the over-writing of data to make it unrecoverable, the modification of filesâ metadata and file obfuscation (disguising files). | eng_Latn | 4,907 |
How to enhance VB6 programming experience? | Alternative IDE for VB6 and VBA | How to completely remove virtual packages? | eng_Latn | 4,908 |
ASP.Net Core app obfuscation | Protect .NET code from reverse engineering? | .NET obfuscation tools/strategy | eng_Latn | 4,909 |
How to recognize which virtual environment is being used | Easy way to determine the virtualization technology of a Linux machine? | Multiple (diamond) inheritance compiles without "virtual", but doesn't with | eng_Latn | 4,910 |
Memory Forensics of a Java Card Dump | Searching for processes and threads in Microsoft Windows memory dumps | computer forensics field triage process model . | eng_Latn | 4,911 |
what is xxe vulnerabilities | XXE is a vulnerability in the way that XML parses handle user input and if an attacker is able to enter arbitrary or crafted data into an XML parser they may be able to inject entities and this could leave to file disclosure, denial-of-service attacks or in rare cases â code execution! | Meltdown and Spectre: Explaining the two new security vulnerabilities 4 January 2018 Various researchers, including Google Project Zero, have today disclosed two critical processor vulnerabilities, named âMeltdownâ and âSpectreâ. These vulnerabilities affect laptops and workstations from all major manufacturers including HP, Dell, Microsoft, Apple etc. | eng_Latn | 4,912 |
Hide code in packages I packaged a visualforce page and its controller but the code is still able to be seen. How can I hide my code? Thanks in advance. | How can I hide my code in visualforce page? I developed my app, The controller is complete, and also the visualforce, but I need to hide my code at installing the app in another salesforce account. How can I make this possible? Is there any way to hide both codes? The apex and the code behind? Thanks in advance. | Why are papers without code but with results accepted? I just started reading some papers (Computer Science, specifically Computer Vision) and thought "now let's look at the source code" and was quite astonished that most of the papers don't have any source code implementing the described methods to look at, while claiming some performance or being better than other papers. How do these papers get accepted in journals / conferences? Do people have to submit their source code privately to the reviewers at least, so that they can reproduce the experiment if possible. Do most journals / conferences just "trust" that people who submit the paper really implemented the theory and got those exact results? I always had this idea that any experiment should be reproducible by others else it's not scientific justified. Been wondering about this the last few days. | eng_Latn | 4,913 |
how to Convert ASM to c++? | Is there a C++ decompiler? | Why are drivers and firmwares almost always written in C or ASM and not C++? | eng_Latn | 4,914 |
Was DJ the hacker they were looking for? | Who was the real "Master Code Breaker"? | how to tell Latex to ignore empty lines | eng_Latn | 4,915 |
polymorphic refers to a malware's ability | metamorphic and polymorphic malware. Metamorphic and polymorphic malware are two categories of malicious software programs (malware) that have the ability to change their code as they propagate. Download: IoT Security Best Practices. For many, security tops the list of IoT challenges. | About Malware. Malware is an abbreviated term meaning âmalicious software.â This is software that is specifically designed to gain access or damage a computer without the knowledge of the owner. There are various types of malware including spyware, keyloggers, true viruses, worms, or any type of malicious code that infiltrates a PC. | eng_Latn | 4,916 |
what are malware signatures | A unique string of bits, or the binary pattern, of a virus. The virus signature is like a fingerprint in that it can be used to detect and identify specific viruses. Anti-virus software uses the virus signature to scan for the presence of malicious code.he virus signature is like a fingerprint in that it can be used to detect and identify specific viruses. | Antivirus software detects and removes malware such as viruses, Trojans, and worms. Signature-based antivirus software detects known malware based on signature definitions. Heuristic-based software detects previously unknown malware based on behavior. | eng_Latn | 4,917 |
what is the purpose of a rootkit? | Many rootkits can even hide large collections of files and thus enable an attacker to store many files on your computer invisibly. Rootkits do not infect computers by themselves like viruses or worms do. Instead, an attacker identifies an existing vulnerability in a target system. | If both the conditions are fulfilled, Stuxnet introduces the infected rootkit onto the PLC and Step7 software, modifying the codes and giving unexpected commands to the PLC while returning a loop of normal operations system values feedback to the users. | eng_Latn | 4,918 |
High-frequency electric fields as lethal agents for insects. | Control of maize weevil ( Sitophilus zeamais Motschulsky ) and lesser grain borer ( Rhyzopertha dominica ( F . ) ) by radio frequency | The impact of extremely low frequency electromagnetic fields on stream periphyton: an eleven-year study | eng_Latn | 4,919 |
Electrochemical migration of land grid array sockets under highly accelerated stress conditions | Silver migration in electrical insulation | Lack of Marburg Virus Transmission From Experimentally Infected to Susceptible In-Contact Egyptian Fruit Bats. | eng_Latn | 4,920 |
The Aspect of Power Supply in Exploitation of Transport Telematics Systems | Issue of Reliability–Exploitation Evaluation of Electronic Transport Systems Used in the Railway Environment with Consideration of Electromagnetic Interference | Lack of Marburg Virus Transmission From Experimentally Infected to Susceptible In-Contact Egyptian Fruit Bats. | eng_Latn | 4,921 |
A miniaturized common-mode filter composed of multiple substrates with positive and negative coils formed on alternate substrates is proposed in this paper. The pattern of each positive coil is interlaced with that of each negative coil, whereby when the positive and negative coils are alternately stacked, the positive coils do not overlap the negative coils. With such offset configuration, the parasitic capacitance introduced between positive and negative traces is reduced, so the thickness of each substrate can be decreased and the size of the entire filter is effectively reduced. Good agreements between simulated and measured results are demonstrated. Further, the effectiveness of this filter is confirmed by eye diagram and radiation emission measurements. | This paper introduces a codesign of electrostatic discharge (ESD) protection device and common mode suppression circuit on printed circuit board (PCB) for high-speed input/output interfaces. The characteristic and model of ESD protection device are investigated and applied into the design of common mode suppression circuit. The proposed design of two-layered PCB structure performs −10 dB common mode noise suppression from 2.22 GHz to 2.76 GHz; the proposed design with additional common mode suppression cell performs wideband suppression from 2.25 GHz and over 8 GHz. The insertion loss of differential signal for proposed design and reference circuit is similar in experimental result. | Rationale ::: Positive modulators of the benzodiazepine/GABAA receptor complex can heighten aggressive behavior; the GABAA/α1 subunit may play a critical role in benzodiazepine-modulated aggressive behavior. | eng_Latn | 4,922 |
Air-Gap Discharge Characteristics in Foggy Conditions Relevant to Lightning Shielding of Transmission Lines | Interception Probability and Proximity Effects: Implications in Shielding Design Against Lightning | High-speed running performance is largely unaffected by hypoxic reductions in aerobic power | eng_Latn | 4,923 |
Solid candidates, such as RFK (or HRC), weather the charges. | RFK and HRC are solid candidates who weather the charges. | RFK and HRC could never weather the charges. | eng_Latn | 4,924 |
The paper had a study on the role of the mine communication system in the mine safety production dispatching,the safety prevention and the emergency rescue.The paper provided the technical and equipment requirements.①Coal mine shall be equipped with the mine dispatching and communication system.The dispatching telephone can be directly linked with the surface dispatching switchboard (including the safety railing) and shall be power supplied remotely by the dispatching switchboard.The dispatching telephone shall be strictly forbidden to be energized in the underground mine or strictly forbidden to be lined via the powered relay.②The mine surface substation,the surface ventilator room,the main and auxiliary hoist rooms,the surface air compressor room,the underground mine main water pumping chamber,the underground mine central substation,the mine shaft bottom,the underground transportation dispatching chamber,the mining block substation,the underground dip and up winch chamber,the water pumping chamber,the underground belt conveyor central control chamber,the main electric and mechanical equipment chambers,and the near places of the mining and excavation faces and the outburst seam mining faces,the personnel gathering place during the blasting operation,the mining block and high level locations and the underground refuge chamber (or a refuge cabin) shall individually have a dispatching telephone directly linked to the dispatching telephone in the surface dispatching room.③The mine broadcast communication system shall be actively promoted and applied.④The mine mobile communication system shall be actively promoted and applied.⑤In the underground mine,the mine leader on duty,the technical personnel,the mining block team leader,the face team leaders,the mine gas inspectors,the mine safety inspectors,the electric bench workers would be better to individually have a mine mobile telephone.⑥The mine rescue team shall be equipped with the mine emergency rescue communication system.⑦The IP telephone communication system and the mine mobile communication system shall be forbidden to replace the mine dispatching communication system. | The RFID technology of personnel orientation in coal mine is introduced in this article. Combined with special circumstances and special coal mine safety regulations, the unavoidable collision problem in RFID is also analyzed detailedly. It points out the deficiencies of the general anti-collision algorithm. Then it brings forward an improved anti-collision algorithm, which is significative for enhancing performance of personnel orientation system in coal mine. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,925 |
Electromagnetic Compatibility Operational Problems Aboard the Apollo Spacecraft Tracking Ship | PARASITIC RF GAS DISCHARGES AS RECTIFIERS AND INTERFERENCE GENERATORS | Electron dynamics in collisionless magnetic reconnection | eng_Latn | 4,926 |
Optimal operation of contactless transformers with resonance in secondary circuits | System conditions monitoring method for a wireless cellular phone charger | Cadaver donor discards secondary to serology. | eng_Latn | 4,927 |
Computational model of grounding systems | Hybrid approach for modeling transient EM fields generated by large earthing systems | No evidence for apparent extent between parallels as the basis of the Poggendorff effect | eng_Latn | 4,928 |
Measurement and modeling of system-level ESD noise voltages in real mobile products | Numerical modeling of electrostatic discharge generators | Sensorless vector and direct torque control | eng_Latn | 4,929 |
Analysis of Microwave Electromagnetic Compatibility in Shielding Electronic System | On the Addition of EM Field Propagation and Coupling Effects in the BLT Equation | Advancement in power system engineering education and research with power industry moving towards deregulation | eng_Latn | 4,930 |
EFFECT OF SEMICON-INSULATION INTERFACE ON SPACE CHARGE FORMATION IN HVDC POLYMERIC CABLES | Interfaces: To be avoided or to be treasured? What do we think we know? | Oral spray wintertime vitamin D3 supplementation has no impact on inflammation in Gaelic footballers | yue_Hant | 4,931 |
MODIFICATIONS OF DIODE RECTIFIER CIRCUITS FOR CONTINUOUS INSULATION MEASUREMENT IN LIVE AC IT NETWORKS | Protective Measures with Insulation Monitoring | Delayed Reactive Distractor Suppression in Aging Populations | yue_Hant | 4,932 |
Advanced Composite Aircraft Electromagnetic Design and Synthesis | Techniques for measuring the electromagnetic shielding effectiveness of materials. I. Far-field source simulation | Nitroaromatic Compounds, from Synthesis to Biodegradation | eng_Latn | 4,933 |
The paper proposes an approach to investigate the fine structure of the voltages circulating in the industrial network within the range of 300 kHz-20 MHz, which serves to do some measurements of real lines in real operating mode. It is shown that the interferences can be divided into basic- with spectral density changing slowly with frequency alteration and narrow-band (frequency-pulse). It is also indicated that the frequency concentrated interferences occupy usually 1-5% of the frequency range studied and their intensity is deeply modulated with the doubled frequency of the power supply voltage. There are areas with distinctly expressed low interferences around the zero transitions. The study is motivated by the search for sophisticated methods of high-speed data exchange through the power network. | In-building power lines have been considered as a medium for high speed data transmission for applications like home networking and Internet access. Frequency selectivity and time variation of this medium in addition to the high level of narrow-band and impulsive interference makes multi-carrier modulation, and especially its popular variant discrete multitone (DMT), an attractive modulation candidate for this application. This paper presents the results of our measurements of the high frequency characteristics of ordinary in-building power lines, as well as simulation results of a DMT transceiver system in an in-building power line environment. | [1] The origins of rip current pulsations within the infragravity frequency band (0.004–0.04 Hz) are determined from measurements made with arrays of colocated pressure and velocity sensors deployed on a beach with persistent rip current channels. The observations indicate significant energy in cross-shore infragravity velocities that varies spatially in the alongshore due to the presence of rip channels. Infragravity velocities are smaller within the rip channel than on the shore-connected shoal owing to differences in water depth. Rip current pulsations at infragravity frequencies are linked to standing infragravity motions but not to the ponding and subsequent release of water by wave group pumping. | eng_Latn | 4,934 |
In order to realize fast handover in both microcells and macrocells, the relationship between averaging, the received signal level comparison method, and handover detection delay was analyzed. The analytical results were verified by handover simulations performed using experimental propagation data. As the criterion for accurate and stable handover in both the macrocell and the microcell, a combined handover decision is suggested which consists of long-term averaging with a small hysteresis margin and short-term averaging with a large hysteresis margin. > | In this work, we propose a framework to obtain estimators from a variety of distributions used in composite fast fading and shadowing modeling with applications in wireless communications: the Suzuki (Rayleigh-lognormal), Nakagami-lognormal, K (Rayleigh-gamma), generalized-K (Nakagami-gamma) and α-μ (generalized gamma) distributions. These estimators are derived from the method of moments of these distributions in logarithmic units, usually known as log-moments. The goodness-of-fit of these estimators to experimental distributions has been checked from a measurement campaign carried out in an urban environment. Moreover a new method to separate fast fading and shadowing based on the Rathgeber procedure is proposed. The results conclude that the best-fitting distribution to the measurements is the Nakagami-lognormal. Also, the α-μ distribution provides an acceptable matching with the advantage of its simplicity. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,935 |
UHVDC wall bushing is a key equipment which connects valve hall and DC yard, and it loads total voltage and current. In this paper, concerning the charge relaxation process and weakly ionized gas conductivity model (based on natural ionization, ion migration and diffusion motion), the electric field simulation model of wall bushing was established, the shielding effect regulated by single/double layer shield structure (SLSS /DLSS) were studied. The result indicated that: The DLSS, compared to SLSS, can significantly reduce the field strength on both sides of the insulator and surface of the internal electrode. The electric field distribution on the air side of the insulator under DC voltage is not affected by the different configuration (SLSS or DLSS) of the inner shield electrode, but the DLSS can still reduce the surface of the inner electrode of the casing relative to the SLSS. This work is aim to report the regulating effect on field distribution by DLSS under different voltages in details, which can provide a basic reference for insulating structure design of 1100KV UHVDC SF6 gas-insulated wall bushing. | This paper investigates the power frequency electric fields around a 1000-kV ultra-high voltage (UHV) substation which is located in Jingmen, China. Detailed field measurements around this substation as well as numerical results in a 1000-kV area are provided. Most values observed are below the reference level indicated in the relevant national design guideline. Therefore, we can conclude that the power frequency electric fields around this UHV substation are safer for working personnel. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,936 |
Cone penetration testing (CPT) in Canada is usually performed using locally available drilling rigs. The limited pushing capacity of most drilling rigs coupled with the risk of damage to expensive cone penetrometers has tended to restrict the CPT to generally loose or soft soils. Therefore, in regions dominated by stiff glacial soils the more rugged standard penetration test (SPT) is still the most commonly used in situ test during geotechnical investigations. However, there are many limitations with the SPT with respect to interpretation and repeatability, especially the uncertainty with the energy delivered from various SPT hammer anvil systems. A downhole cone penetration test (DCPT) has been developed by modifying the equipment and procedure of the standard electric CPT. The DCPT consists of a simple, inexpensive electric cone penetrometer attached to a 1.5 m (5 ft) length of AW drill rod. The test is performed by pushing the cone 1.5 m into the base of an open borehole to produce a continuous profile... | This report examines the most current literature and information available on characterization and remediation technologies that could be used on the Nevada Test Site (NTS) historical hydronuclear test areas. Historical hydronuclear tests use high explosives and a small amount of plutonium. The explosion scatters plutonium within a contained subsurface environment. There is currently a need to characterize these test areas to determine the spatial extent of plutonium in the subsurface and whether geohydrologic processes are transporting the plutonium away from the event site. Three technologies were identified to assist in the characterization of the sites. These technologies are the Pipe Explorer{trademark}, cone penetrometer, and drilling. If the characterization results indicate that remediation is needed, three remediation technologies were identified that should be appropriate, namely: capping or sealing the surface, in situ grouting, and in situ vitrification. Capping the surface would prevent vertical infiltration of water into the soil column, but would not restrict lateral movement of vadose zone water. Both the in situ grouting and vitrification techniques would attempt to immobilize the radioactive contaminants to restrict or prevent leaching of the radioactive contaminants into the groundwater. In situ grouting uses penetrometers or boreholes to inject the soil below the contaminantmore » zone with low permeability grout. In situ vitrification melts the soil containing contaminants into a solid block. This technique would provide a significantly longer contaminant immobilization, but some research and development would be required to re-engineer existing systems for use at deep soil depths. Currently, equipment can only handle shallow depth vitrification. After existing documentation on the historical hydronuclear tests have been reviewed and the sites have been visited, more specific recommendations will be made.« less | Electric vehicles (EVs) are quickly gaining widespread interest as attractive alternatives to conventional petrol driven vehicles. If EVs derive some or all of their power from renewable sources, then they can help reduce global dependence on fossil fuels for transportation. Inductive power transfer (IPT) is a method that can transfer power to EVs over an air gap without physical contact. If IPT systems are incorporated into highways, then EVs can be charged dynamically as they travel. This will dramatically increase the range, convenience and safety of EV charging as well as reduce range anxiety and battery bank capacities. One of the major difficulties involves detecting an EV as it travels along the highway. By detecting the approaching EV, the primary power supply can energize the primary IPT coupler buried in the roadway to enable contactless power transfer to the EV. A three coil detection system, which focuses on these sensor coils and which is independent of the specific IPT coupler used, is presented to allow the power supply to detect the approaching EV mounted secondary IPT coupler. The proposed detection method was tested on a laboratory scale prototype and can detect EVs approaching at different speeds, ground clearances, and horizontal misalignments. | eng_Latn | 4,937 |
With the increasing need of transmitting electrical energy over very long distances, combined with necessary space saving installations, the focus is more and more shifted to DC operated gas insulated systems. Their insulation system is nearly uniform, hence well-known problems, like space charge accumulation and metallic particles become more critical using SF6 in comparison to non-uniform air insulations. As soon as the applied voltage exceeds the inception voltage at the particle tips, the particle will produce charge carriers. These space charges will accumulate on the insulator and possibly influence the flashover behaviour. For a systematic study, variable parameters as the size of the particle and its position relative to the high voltage electrode, were chosen. In this paper, the flashover behaviour of epoxy resin insulators with adhesive metallic particles under both positive and negative DC voltage stress in gas insulated systems was investigated. | Particle-initiated breakdown characteristics in SF6 gas are investigated. Breakdown voltages are greatly influenced by particle diameter especially for AC voltages, and for very fine metallic wire particles are much higher than those for moderately thick ones. The breakdown stress of a gas gap is obtained as a function of particle length and can be estimated fairly well by assuming a corona stabilizing zone. For a spacer, the electric stress which is parallel to its surface dominates surface breakdowns and the relation between the stress and particle length is experimentally determined. In order to increase breakdown voltages, the effects of both the dielectric coating on a high-voltage electrode and spacer shape are examined. Finally, the effectiveness of the dielectric coating on a grounded electrode is demonstrated to prevent particle levitation. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,938 |
This paper describes a knowledge-based system for the analysis and design of the protection a system element or group of elements such as a substation. The structure of the knowledge-based system is based on an object-oriented approach in order to manipulate and reuse the functions and protection algorithms. Given the input requirements, the knowledge-based system will propose a protection system in the form of a generic relay based on an events-and-consequences methodology. | This paper presents a knowledge-based approach to the design of protection systems and their associated equipment. The paper begins with an examination of the characteristics of an expert system, its properties and benefits. These follow a discussion of the basic structure of a knowledge-based system with particular reference to protection systems. A standardized methodology is then introduced whereby a design can be produced to meet a set of specifications. To illustrate this process, the protection systems of a typical substation are outlined by applying the various steps of the methodology and providing the appropriate explanations. A principal characteristic of this expert system is the attention given to the coordination that should exist between the protection system design and that of the power system itself so that the protection function is an integral part of power system operation. | This paper presents a knowledge-based approach to the design of protection systems and their associated equipment. The paper begins with an examination of the characteristics of an expert system, its properties and benefits. These follow a discussion of the basic structure of a knowledge-based system with particular reference to protection systems. A standardized methodology is then introduced whereby a design can be produced to meet a set of specifications. To illustrate this process, the protection systems of a typical substation are outlined by applying the various steps of the methodology and providing the appropriate explanations. A principal characteristic of this expert system is the attention given to the coordination that should exist between the protection system design and that of the power system itself so that the protection function is an integral part of power system operation. | eng_Latn | 4,939 |
Electrical Power Systems Availability in Buildings Exposed to Seismic Hazard—Part I: Electrical Criteria and Part II: Mechanical Criteria | Service Continuity Safety by Design: The Relevance of Electrical Power-System Architectures in Hospitals | Advancement in power system engineering education and research with power industry moving towards deregulation | eng_Latn | 4,940 |
A Compact Tri-Band PIFA with Multiple-Folded Parasitic Elements | System With RF Power Delivery Capabilities for Active Safety Enhancement in Industrial Vehicles Using Interchangeable Implements | High-affinity glucose uptake in Saccharomyces cerevisiae is not dependent on the presence of glucose-phosphorylating enzymes | eng_Latn | 4,941 |
Modeling of indoor power line for substation monitoring using broadband power line communications | Indoor power line channel characterization for data transfer and frequency response measurements | Suppression of bremsstrahlung and pair production due to environmental factors | eng_Latn | 4,942 |
Investigations of time delays in microwave breakdown initiation | Global Model for Total Delay Time Distribution of High-Power Microwave Surface Flashover | Completely Stale Transmitter Channel State Information is Still Very Useful | eng_Latn | 4,943 |
This paper presents a forward error correction technique that can be applied to protect JPEG2000 streams during their transmission over wireless channels with both sparse and packet error statistics. To this aim, we adopt the tools of the JPEG2000 Wireless (JPWL) standard, by introducing a method for Unequal Error Protection (UEP) and a virtual interleaving technique of the stream. All these techniques are introduced while keeping a complete backward-compatibility with the existing standard. | One of the aims of the standardization committee has been the development of Part I, which could be used on a royalty- and fee-free basis. This is important for the standard to become widely accepted. The standardization process, which is coordinated by the JTCI/SC29/WG1 of the ISO/IEC has already produced the international standard (IS) for Part I. In this article the structure of Part I of the JPFG 2000 standard is presented and performance comparisons with established standards are reported. This article is intended to serve as a tutorial for the JPEG 2000 standard. The main application areas and their requirements are given. The architecture of the standard follows with the description of the tiling, multicomponent transformations, wavelet transforms, quantization and entropy coding. Some of the most significant features of the standard are presented, such as region-of-interest coding, scalability, visual weighting, error resilience and file format aspects. Finally, some comparative results are reported and the future parts of the standard are discussed. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,944 |
Although Poynting's theorem receives general acceptance in the treatment of electromagnetic energy, an alternative theorem, Macdonald's, has equal claim to validity at the present state of our know... | Methods of calculating and measuring the flow of electromagnetic energy are compared and contrasted. The differences between the low-frequency and high-frequency approaches to energy flow problems are discussed and suggestions are made to ease the difficulties in the way of students and teachers faced with these apparently irreconcilable differences. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,945 |
In this paper a three core high-voltage underground cable used for urban power networks is analyzed by means of Finite Element Method. The electrical analysis is performed in order to investigate the electric stress within the cable, also in presence of defect in the insulation layer. The electro-thermal analysis permits the full description of the cable behavior not only in terms of electric and magnetic performances, but also regarding the effect of the Joule heating on the surrounding ambient. | HTS power cables appear to be the replacement and retrofitting of underground cable in urban areas and HTS power cable offers a number of technical and economic merits compared to normal conductor cable system. A 3 phase 22.9 kV, 50 MVA class HTS power cable system have been developed by Korea Electrotechnology Research Institute (KERI), LS Cable Ltd. and Korea Institute of Machinery and Materials (KIMM) that is one of 21st century frontier project in Korea. The 30 m long cable with 3 cores in 1 cryostat has been manufactured and installed to conduct long-term reliability test. The HTS power cable consists of two layers of phase conductor and two layers of shield used Ag/Bi-2223 tapes and polypropylene laminated paper is used in LN2 as electrical insulation. A HTS power cable has been tested with DC and rated current and voltage in pressurized liquid nitrogen. The evaluation results clarify good performance of HTS cable and these results prove that the HTS power cable has the basic electrical properties for 22.9 kV HTS power cable. This paper describes the results of developmental the 30 m, 3 phase, 22.9 kV, 50 MVA HTS power cable in Korea | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,946 |
Several factors have spurred improvements in driving simulators in recent years. First, improved simulator and computer technologies available at lower costs have significantly expanded driving simulator capabilities compared with previous designs. Second, the emergence of advanced automotive technologies and the potential proliferation of in-vehicle communications and navigation systems associated with intelligent transportation systems underscore the need for safe and inexpensive ways to test these systems to ensure they meet safety and regulatory requirements. Finally, the decline in military spending and coinciding rise in defense conversion activities have caused defense contractors to aggressively pursue automotive applications, further stimulating interest. This article provides information on advanced driving simulator technologies, European advanced driving simulators, and advanced driving simulator developments in the United States, including the National Advanced Driving Simulator (NADS). | This paper discusses the development, application and validation of an affordable, moderately high fidelity simulator using appropriate technology for driver training, licensing and assessment, issues of increasing concern as roads become more crowded, vehicles more laden with complex technology (intentional and otherwise), and driving population older. It reports on a series of diverse, loosely coordinated research projects at several institutions in North America. These projects, taken individually, evaluated the viability of simulation for multiple applications. Despite this diversity, however, and despite the breadth of the organizations performing this research (including universities, hospitals, motor vehicle agencies, law enforcement training academies and standards-setting bodies), there is a common thread that binds these programs together. That is, they are each part of an integrated effort to develop, refine, test and validate a particular simulator technology, one which has the potential for widespread application. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,947 |
A generalized class of normalized distance functions called Q-metrics is described in this paper. The Q-metrics approach relies on a unique functional, using a single bounded parameter lambda, which characterizes the conventional distance functions in a normalized per-unit metric space. In addition to this coverage property of the proposed model, a distinguishing and extremely attractive characteristic of the Q-metric function is its low computational complexity. We present a formal mathematical proof that Q-metrics satisfy the standard metric axioms. A novel artificial neural network is completely defined and constructed using Q-metrics. This new network is shown to outperform a conventional feed forward back propagation network with the same size when tested on real data sets. | As diverse smart grid applications are as different are their specific requirements on the used information exchange. In most of the researched cases a specific communication technology is proposed to connect one single type of application with the smart grid. From the view of exploiting already existing similarities between applications it might be interesting to locate synergies between different applications, which are located at the same place to share the same communication channels. In this work a method is presented that should help to measure how different given sets of requirements on the communication technology are. In that way different applications can be made comparable, as far as their requirements on communication technologies are concerned, and a numeric value indicating the similarity can be calculated. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,948 |
The paper gives an overview about today's field trials and deployments and also explains the pro's and con's of infrared (IR) beacon communication. During the early eighties, first concepts for dynamic route guidance systems appeared in Europe, the US and Japan. In Europe, after successful performance of the LISB field trial in Berlin, EURO-SCOUT - using IR beacon communication - was developed. In Japan, field trials with microwave beacons (in RACS) as well as RF communication (in AMTICS) were carried out and recently, the Japanese Nafional Police Agency (TWA) has opted for short-range communication using IR beacons. NPA sponsors today a large scale field trial with 3,000 IR beacon heads and 500 participating vehicles. In Germany, the newly founded private company for route guidance and driver information semces COPILOT has already deployed IR beacons in Stuttgart and Berlin. Operational field tests with IR beacons are also being performed in the USA. Furthermore, in the German electronic toll collection field trial qualified technologies compete in a multi-lane, free-flow, and high speed environment. Siemens participates with its ChipTicket System relying on IR communication between roadside and vehicles. | The infrared docking aid system was developed and investigated to help small craft such as fishing or recreation boats when they sailed close to the pier or port. The experiment was conducted in water tank with the scaled model boat. The system consisted of the infrared beacon locating at the port and the infrared detection array installed in the modeled boat. The results suggested that the system was capable to navigate the boat to dock in the correct position as the boat came in small angle from beacon. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,949 |
Unique properties of electromagnetic precursors in causally dispersive media are described from both mathematical and physical perspectives. | : This report presents a targeted survey of standards and other research on the safety to humans of short pulses of electromagnetic radiation. Special attention is paid to a ten nanosecond pulse allowing a comparison of the permitted power levels according to various standards and recent research. This report notes that power levels allowed by IEEE standards have, in some cases, changed by several orders of magnitude over recent years. Recent research is presented showing that the adequacy of current standards is far from a settled issue. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,950 |
This paper presents a new mathematical approach to modeling EM wave coupling noise so that it can be easily integrated into chip-level noise analysis tools. The new method employs Chebyshev approximation technique to model the distributed sources arising in the Telegrapher's equations due to EM wave coupling. A uniform plane wave illumination metric is provided to determine the order of approximation. Closed-form formulas for the noise transfer functions' moments are derived. By utilizing the formulated moments, reduced order models can be efficiently obtained to generate the induced noise caused by EM wave illumination. The accuracy of the proposed method is verified by Hspice simulation. | This paper describes PRIMA, an algorithm for generating provably passive reduced order N-port models for RLC interconnect circuits. It is demonstrated that, in addition to requiring macromodel stability, macromodel passivity is needed to guarantee the overall circuit stability once the active and passive driver/load models are connected. PRIMA extends the block Arnoldi technique to include guaranteed passivity. Moreover, it is empirically observed that the accuracy is superior to existing block Arnoldi methods. While the same passivity extension is not possible for MPVL, we observed comparable accuracy in the frequency domain for all examples considered. Additionally a path tracing algorithm is used to calculate the reduced order macromodel with the utmost efficiency for generalized RLC interconnects. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,951 |
Editor’s note: The authors target the typical problem of a small number of test access ports. As a solution, they propose a set of interposers to obtain access to the tested nets. Jorg Henkel, Karlsruhe Institute of Technology | Through-silicon vias (TSVs) provide high-density vertical interconnects between dies and enable the creation of 3-D ICs having higher performance and lower power consumption than traditional 2-D ICs. A practical TSV-based 3-D integration approach is to place multiple dies (or die stacks) side by side on a passive silicon interposer base, in which there are TSVs and metal wires serving as interconnects. In this paper, we propose a post-bond design-for-test architecture and a test strategy for such interposer-based 3-D ICs. Functional package pins and interconnects are reused to build multibit parallel test access mechanisms (PTAMs), which provide post-bond test access with no or low extra area costs. Four PTAM architectures are presented, and the corresponding PTAM optimization algorithms are proposed which can quickly identify the best PTAM configuration to achieve the shortest test time. We also propose an algorithm for adding dedicated test interconnects to improve test bandwidth at the expense of extra microbumps and metal wires. Experimental results show that the proposed techniques are effective in test length (and therefore test time) reduction. Moreover, cost-benefit analysis results suggest that our approaches have lower total test costs compared with a base-case one-bit JTAG-only solution. | Electric vehicles (EVs) are quickly gaining widespread interest as attractive alternatives to conventional petrol driven vehicles. If EVs derive some or all of their power from renewable sources, then they can help reduce global dependence on fossil fuels for transportation. Inductive power transfer (IPT) is a method that can transfer power to EVs over an air gap without physical contact. If IPT systems are incorporated into highways, then EVs can be charged dynamically as they travel. This will dramatically increase the range, convenience and safety of EV charging as well as reduce range anxiety and battery bank capacities. One of the major difficulties involves detecting an EV as it travels along the highway. By detecting the approaching EV, the primary power supply can energize the primary IPT coupler buried in the roadway to enable contactless power transfer to the EV. A three coil detection system, which focuses on these sensor coils and which is independent of the specific IPT coupler used, is presented to allow the power supply to detect the approaching EV mounted secondary IPT coupler. The proposed detection method was tested on a laboratory scale prototype and can detect EVs approaching at different speeds, ground clearances, and horizontal misalignments. | eng_Latn | 4,952 |
This paper examines the construction of the coordination contour around the stations of the conventional fixed service operating in the same frequency bands with the mobile Earth stations located on board vessels (ESVs). A new method for the realistic calculation of the coordination area is presented. This method takes into account the mobility parameters of the interfering stations such as their velocity and their frequency of passage from specific locations around the FS station and the specific interference conditions. Simulations in real interference environments prove its validity. Useful results for the coordination procedure between the two services are extracted and thoroughly discussed | This paper examines the potential interference between the mobile satellite service and the fixed service in the Ku band. At first, the aggregate and the single-entry interference criteria for the terrestrial fixed service stations are calculated. Then, all the parameters that influence the interference magnitude are presented and extensively analyzed. In order to evaluate the impact of each one of them in the interference calculations, different scenarios are taken into consideration and simulations are conducted. The results are thoroughly presented and analyzed. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,953 |
This study describes a procedure of condition assessment for distribution grids, which is applicable in an economical, non-intrusive and practical way. The assessment procedure is based on periodic visual inspections. It is additionally supplemented by suitable and simple measurement methods which can be used without any disconnection of the components and thus without much additional effort during an inspection. Therefore, suitable non-intrusive measurement methods for medium-voltage substations and switchgears as well as low-voltage distribution cabinets will be presented in relation to an integrated condition assessment of distribution grids. However, significance of these non-intrusive measurement methods is limited. Using the example of acoustic partial discharge detection measurement uncertainties will be determined by intensive laboratory tests and numerous field tests realised with several German distribution system operators. These values will be combined with condition information of visual inspections by using theory of evidence to express the uncertainty. Since measurements and visual inspections detect different kinds of deficiencies of electrical equipment, a combination of both is crucial to achieve a high significance of condition assessment as shown in this study. | The theoretical sensitivity of conventional partial discharge detectors is compared with that obtained from ultra wideband (UWB) (up to l GHz) detection systems. The comparison indicates that for relatively lossfree distributed systems, such as SF6 insulated bus, the UWB system is up to two orders of magnitude more sensitive. UWB detection also embodies additional advantages such as facilitating the location of discharge sites and the rejection of external electrical noise. For discharge detection in plastic-insulated cables, true UWB detection is not practical because of frequency-dependent attenuation effects, although certain gains in sensitivity can be achieved with a detector bandwidth of up to 10 MHz. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,954 |
In this paper, we present a kind of null-coupled canceling (NCC) coil to shield electromagnetic fields (EMFs) for wireless power transfer (WPT) systems. The proposed NCC coil is based on the particular zero-mutual-inductance characteristic between two general coils. The working principles, shielding effectiveness, and practical expansions of the proposed NCC coil are illustrated. Furthermore, locating of the zero-mutual-inductance position and determination of the canceling coil current are elaborated, and effects that an NCC coil exerts on the output power, efficiency, and misalignment tolerance of the applied WPT system are theoretically studied. Finally, targeted at our predesigned electric vehicle wireless charging-oriented WPT prototype, a practical NCC coil is built and tested with comparative experiments with the prevalent aluminum (Al) plate shielding. The experimental results show that, with a properly chosen canceling current, the proposed NCC coil could not only shield the EMF more effectively, but also cause a lower efficiency reduction to the applied WPT system than an Al-plate does. | Electric vehicles (EVs) are quickly gaining widespread interest as attractive alternatives to conventional petrol driven vehicles. If EVs derive some or all of their power from renewable sources, then they can help reduce global dependence on fossil fuels for transportation. Inductive power transfer (IPT) is a method that can transfer power to EVs over an air gap without physical contact. If IPT systems are incorporated into highways, then EVs can be charged dynamically as they travel. This will dramatically increase the range, convenience and safety of EV charging as well as reduce range anxiety and battery bank capacities. One of the major difficulties involves detecting an EV as it travels along the highway. By detecting the approaching EV, the primary power supply can energize the primary IPT coupler buried in the roadway to enable contactless power transfer to the EV. A three coil detection system, which focuses on these sensor coils and which is independent of the specific IPT coupler used, is presented to allow the power supply to detect the approaching EV mounted secondary IPT coupler. The proposed detection method was tested on a laboratory scale prototype and can detect EVs approaching at different speeds, ground clearances, and horizontal misalignments. | ABSTRACTUNC-45A is an ubiquitously expressed protein highly conserved throughout evolution. Most of what we currently know about UNC-45A pertains to its role as a regulator of the actomyosin system... | eng_Latn | 4,955 |
In this paper, we proposed a construction of irregular QC-LDPC codes with improved Approximated Cycle Extrinsic Message Degree (ACE) properties. The codes construct using the algorithm proposed have simple structure with good performance. Simulation results show that the proposed algorithm outperforms original PEG algorithm in the error-floor region. | This paper presents a joint low-density parity-check (LDPC) code-encoder-decoder design approach, called Block-LDPC, for practical LDPC coding system implementations. The key idea is to construct LDPC codes subject to certain hardware-oriented constraints that ensure the effective encoder and decoder hardware implementations. We develop a set of hardware-oriented constraints, subject to which a semi-random approach is used to construct Block-LDPC codes with good error-correcting performance. Correspondingly, we develop an efficient encoding strategy and a pipelined partially parallel Block-LDPC encoder architecture, and a partially parallel Block-LDPC decoder architecture. We present the estimation of Block-LDPC coding system implementation key metrics including the throughput and hardware complexity for both encoder and decoder. The good error-correcting performance of Block-LDPC codes has been demonstrated through computer simulations. With the effective encoder/decoder design and good error-correcting performance, Block-LDPC provides a promising vehicle for real-life LDPC coding system implementations. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,956 |
This paper describes the continuity of the development ultrasonic listening device that capable in capturing the ultrasonic sound produced by discharges in the insulation. The device is designed using the wideband amplifier that provides a wide bandwith range that covers from 10 Hz up to 100 kHz. The design of the device has been improved by adding the parabolic reflector. With this improvement, the detection sensitivity is increased up to 160 centimetres, therefore, the device able to detect the discharges for underground cable. In standard detection procedure, the power system needs to be offline in order to assemble the detection device such as sensors prior to the detection process. This device will be an added value compared to the conventional device; where the detection work can be done while the power system is still online. Moreover, the method of detection is purely a non contact method; without any detection device such as sensors to be attached to the affected insulation. Besides it is low in cost, this device promise a simple and practical usage to the users. To the extension of the design, this device can be used to detect partial discharge in the insulation of overhead power cable and underground cable without having to dig out the cable. | Electrical discharges that do not completely bridge the electrodes are called partial discharges. Although small, these discharges have been known for more than fifty years to cause progressive deterioration. Since 1945 the use of new high voltage dielectrics has required the use of sophisticated detection techniques. Discharge detection has grown into an indispensible tool for the evaluation of modern insulation. The subject has received little attention in books on high voltage techniques although a good deal is scattered in various papers and reports. The object of this book is to collect this knowledge and present it as a coherent study. Topics covered include the behaviour detection and measurement of discharges, the choice of detection method and procedure, the location of discharges and discharge detection in practice. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,957 |
Dielectric parameters vary with frequencies are important properties of biological systems, which determine the absorption rates of electromagnetic radiation in human body. Two phase dielectric model is considered to investigate the dielectric properties of human blood in this paper. This paper systematically calculates the body's specific absorption rate of electromagnetic fields at low frequencies based on the dielectric properties obtained from the Debye model. This study could lay foundation not only for the theoretical basis for further study on electrical properties of biological tissue, but also for the exposure limits of health standard on electromagnetic radiation. | The spatial distribution and temporal dynamics of industrial frequency electric and magnetic fields in St. Petersburg, Kazan, Belgorod and Petrozavodsk has been studied. It is established that electric fields of significant strengths occur near high voltage transmission lines (HVL) only. It is found that sanitary-protection and exclusion zones of the standard size do not always ensure a decrease in electric field strength to maximum allowable levels on their boundaries. Thus, the electric field strength of four HVL in St. Petersburg increases due to the mass construction of high-rise buildings leading to an increase in power consumption. A dependence of the electric field strength on meteorological factors was also determined, primarily on air humidity (direct dependence), and on atmospheric pressure (indirect inverse relationship). The industrial frequency magnetic field produces a variable city-wide background caused by a set of sources. The more intense is the technogenic load, the higher is magnetic induction, which renders it a convenient geoindicator for mapping. Also, the indicators of magnetic induction reflect the characteristics of power networks. Abnormally high values of magnetic induction were recorded in all cities, which are explained by the influence of electric cables. No exceedances of allowable levels of magnetic induction in residential areas were observed. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,958 |
A load current in dc high voltage cables results in a temperature drop across the insulation and hence a radial distribution of the insulation conductivity is found. Direct consequence is an accumulation of space charge in the bulk of the insulation, that may significantly affect its reliability. This phenomenon was modeled in terms of the macroscopic properties of the cable insulation and a numerical procedure was developed for the calculation of the time-dependent space charge and electric field in extruded-type cables. Results of calculations were compared to those of space charge measurements performed on MV-size XLPE cables at different values for the temperature drop. The analysis of the results indicates that the space charge induced by the temperature drop is measurable and that its magnitude and location can be reasonably well estimated by means of the proposed numerical procedure. Moreover, different space charge accumulation mechanisms could be distinguished taking into account the knowledge obtained of the space charge distribution induced by the temperature drop. | This paper deals with the analysis of the effect of temperature gradient applied to polymeric cables on space charge accumulation inside insulation bulk. In particular, experimental measurements on HVDC cable models showed that space charge due to temperature gradient is generally negligible with respect to excess charge injected from the electrodes at electrical fields larger than the threshold for space charge accumulation. The effect of temperature gradient can be revealed only at fields close to the threshold, i.e. 5 to 10 kV/mm, leading, however, to a small extent of charge accumulation, of the order of tens of mC/m3. | In this study, periodic grounded DC trees in cross-linked polyethylene (XLPE) under various DC prestressing times are investigated in the temperature range of 20–80 °C. Space charge behaviors in the samples during DC prestressing are simulated based on the bipolar charge transport model. The results reveal that the DC prestressing time has different effects on the tree growth at different temperatures, which is because that the space charge behavior in the sample during DC prestressing is closely related to the DC prestressing time and the temperature, and it has both promotion effect and impedance effect on the tree growth. The electrical tree characteristics are discussed in detail combined with the space charge behaviors. | eng_Latn | 4,959 |
In this paper, the transient behaviour of a WT during lightning stroke is determined considering the high frequency nature of the lightning impulse current through its flow from WT blades to the grounding system. Following the IEC Standard, type-B arrangement is the recommended one for WT grounding which is composed of a horizontal ring supported with horizontal electrodes and vertical rods. The ring is divided into series of linear horizontal conductors. Each horizontal conductor, horizontal electrode and vertical rod is modelled by its π -equivalent RLC circuit. Furthermore, the WT blade is modelled by π -equivalent RLC network. The tower model is simplified by splitting it into vertical cylinders; each cylinder is represented by π -equivalent RLC circuit. The nodal equations of the grounding system and the WT are written at each discrete time instant. MATLAB software package is used to solve the nodal equations and determine the transient response of WT. The results are compared with the case of turbine grounding through a pure resistance as adopted in the literature. The simulation results are then validated by using PSCAD/EMTDC software package. | The exact solution of the AC/DC resistance ratio of an isolated tubular conductor involves the calculation of values from 12 Kelvin functions. Previous approximate solutions are complicated, and graphical solutions require interpolation from sets of curves. A simplified solution, based on a new formula, is presented. The values of the resistance ratio derived from this formula are within /spl plusmn/1%, of those derived from the exact solution in the practical ranges 0.05/spl les/(thickness/diameter)/spl les/0.40 and 0 2000. For practical tubular conductors, the formula can be used for frequencies up to about 10 kHz, depending on the thickness t and the outer diameter D/sub 2/. The application of the skin effect formula to a steel-cored conductor can result in significant error. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,960 |
In this paper, three-dimensional full-wave numerical models are used to predict the terminal response of unshielded twisted pairs, taking into account skin effect, proximity effect and radiation losses. These parameters are then used to extract equivalent circuits suitable for the time domain analysis by any commercial circuit simulator | A time domain procedure is proposed to analyze by CAD circuit simulators the voltage and current wave propagation in shielded cables taking into account frequency-dependent losses. First, the line is discretized in a series-cascade of line sections. Second, each line section is modeled by a two-port network with lumped time-constant parameters obtained by applying the vector fitting technique. The series-cascade circuits are then analyzed by CAD circuit simulators. The obtained results are compared with those obtained by measurements and by the frequency domain solution of the transmission line equations. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,961 |
The design and realization of supervisory software for distribution feeder automation is illustrated, such as software and hardware platform, architecture, function system, data structure and network topology. The design and implementation of the communication interface of hardware and the core function modules of the software, is descript in detail. | Integrating IEC61850 at TVA's Bradley substation for protection, SCADA, and enterprise applications substation, and enterprise applications. The IEC 61850 standard provides the means to integrate communications, information, and applications into a coherent, flexible, very powerful framework for the secondary system. With its deployment, more information can be exchanged and more applications can be run. And we shall see that integrated, accessible information is truly the enabler of effective and economic substation automation | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,962 |
Combining visual simulation,dynamics simulation with other simulation technologies,a distributed interactive simulation system framework is proposed.The simulation system can be used in development of new weapons and a sweeping sham battle.According to the framework,the simulation system of an army ground mobile robot is realized.ADAMS is used in dynamics simulation subsystem.A dynamic model of the robot is created in ATV.Starting,running directly and turning are simulated.The result data are used in visual simulation by special interfaces.Visual simulation subsystem is realized in MultiGen Creator/Vega.The structure of database and the method for simplifying the models are researched.The visual simulation program is implemented with VegaAPI. | According to the deficiency of real-time and interaction in current visual simulation of automobile engine, a visual simulation of automobile engine was proposed based on Virtual Reality (VR). Firstly, focusing on four-stroke and reciprocating-piston automobile engine, the mathematical model of crank-connecting rod was established, and then that of valve train was obtained by the result data of ADAMS in dynamics simulation. At the same time, the visual model of hierarchical data was set up based on Creator, and local coordinate systems of linkage on motion mechanisms were defined by DOF technology. In addition, the visual simulation program was implemented with Vega Prime and Visual Studio. NET 2003. At last, the test shows that the system performs distinctively in interaction and real-time. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,963 |
Results are presented of an experimental study of the characteristics of the short arc in air which is the major cause of contact erosion in telephone switching circuits. Measurements were made of the arc initiation voltage, the voltage drop across the arc and the minimum arcing current. The following are the main conclusions: (1) For “normal” contacts in air, the arc is initiated at a constant field strength of a few million volts/cm up to separations of about 2–3 mean free paths of an electron in air. At larger separations the arc is initiated at the well known spark breakdown potentials of air. In vacuum the linear relation holds for larger separations followed by a transition into a square root relation V ai = K(d)1/2. (2) For “clean” contacts in air, no constant field strength line is obtained for separations as low as 1600A. Instead, the arc is initiated at the spark breakdown potentials of air, possibly due to adsorbed air molecules or due to breakdown along a longer path at the Paschen's minimum potential. In vacuum, it is speculated that the above square root relation will hold. (3) For “activated” contacts and small separations the arc is initiated at a constant field strength of about 0.6 × 106 volts/cm. (4) For “normal” contacts the minimum arcing current increases with an increase in the maximum current during the arc due to surface contaminations and the arc cleaning action. (5) For arc currents above 1.5 ampere and energies of the order of thousands of ergs the cathode determines the arc characteristics. | People can be exposed to "microshocks" which are caused by the high electric fields present under, or near, high voltage equipment or transmission towers. This is due to the capacitive coupling between the HV equipment and the human body. For example if a person underneath an HV line touches or comes close to touching an earthed object, discharges can occur to the individual. This is known as microshocks. Detailed knowledge of the physics of the discharges between the metallic object and the human body is necessary to model the process successfully. Laboratory measurements of the transient currents and voltages are given in this paper to show the characteristics of microshocks. Simulations in CDEGS and PSCAD/EMTDC are presented and compared to laboratory measurements. Early modelling work is encouraging and future activities are described. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,964 |
Starting with the fundamental field equations of Maxwell, the various approximations involved in the usual engineering formulation of the multiconductor problem are examined. Subject to these approximations, the set of differential equations which is taken as the starting point of the classical transmission theory in the steady state are derived and the character of the various parameters involved in these equations is studied. By the use of the Laplacian transformation and certain theorems of matrix algebra these equations are solved for the case of general terminal conditions. Certain special cases where the system exhibits symmetry are discussed. | A brief chronology of the application of transmission line theory to electromagnetic compatibility (EMC) applications is presented. Transmission line studies in EMC began in the 1950s and 1960s with the frequency-domain analysis of crosstalk in cables. Nuclear electromagnetic pulse (EMP) concerns in the 1970s caused an increasing emphasis on the study of incident field excitation of the lines. The advent of digital technology in the 1980s moved the research emphasis toward the analysis of the transmission lines in the time domain. Early work concentrated on lossless lines whose solutions are very simple. After the 1980s, the impact of high-speed digital technology has driven much of the research toward the study of ways to incorporate line losses (particularly, frequency-dependent losses as with skin effect) into the solutions. In addition, the increasingly complex digital systems have resulted in the study of how to optimize the representation and solution of large interconnected networks of transmission lines. This paper attempts to put the historical evolution of the study of transmission lines in EMC in a chronological perspective. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,965 |
A new approach to build multi-chip modules (MCMs) using active silicon substrate (ASIS) technology is being developed by Lockheed for future sensor signal processing and control applications. The ASIS MCM inherently offers a functional platform versus other approaches using a passive nonfunctional substrate. The Lockheed ASIS design uses benzocyclobutene (BCB) for a low dielectric and copper for interconnect over an active substrate. Support chips are attached to the interconnect over the substrate by solder bumps. This provides a versatile manufacturing concept for easy rework. Bare die testing and bum-in of support chips should eliminate most rework. The result is a dense, high performance, three-dimensional MCM of closely placed functional elements. Unique architectures are possible with optimized active substrates and support chips, but this approach also allows MCMs to be developed sooner with standard integrated circuits. | This paper reviews the state-of-the-art in three-dimensional (3-D) packaging technology for very large scale integration (VLSI). A number of bare dice and multichip module (MCM) stacking technologies are emerging to meet the ever increasing demands for low power consumption, low weight and compact portable systems. Vertical interconnect techniques are reviewed in detail. Technical issues such as silicon efficiency, complexity, thermal management, interconnection density, speed, power etc. are critical in the choice of 3-D stacking technology, depending on the target application, and are briefly discussed. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,966 |
Integrated circuits (ICs) are often the source of the high-frequency noise that drives electromagnetic emissions from electronic products. A case study is presented where emissions from a printed circuit board containing an automotive microcontroller are reduced significantly through analysis of the coupling mechanisms from the chip to the board and attached cables. Noise generated by the IC is explored through measurements in a semi-anechoic chamber and TEM cell, through near-field scans, and through modifications to the printed circuit board. Noise is driven by the IC through both power and I/O connections. Results show that a ferrite in series with I/O power in this application reduced emissions by 10 dB or more at critical frequencies. Possible causes for emissions from the IC and modifications that might reduce these emissions are discussed. | Knowledge of high-frequency currents in the chip and chip-package are necessary for EMI analysis and prediction, though measurement of these currents may be difficult to obtain in many cases. One possibility is to estimate currents from near-field scan data. In this paper, measurements were made of the magnetic field over a simple circuit and a chip package. The current flowing in the circuit and the chip lead frame was estimated from the compensated near-field data and compared with measurements made directly on the pins. Estimation was performed both with and without structural information of the lead frame. The susceptibility of estimated currents to measurement errors was analyzed. Results show this technique can be a powerful tool for analyzing high frequency chip currents. | Pedestrian-induced vibration comfort is an important factor affecting the serviceability of footbridges. This article proposes a smartphone-based evaluation system for pedestrian-induced footbridge... | eng_Latn | 4,967 |
The results of studying materials based on mica paper and polyester film are presented. Short-term and long-term electrical strength of films and composites are determined. It is found out that addition of polymer film increases the endurance of the composite. The existence of correlation between the durability and PD characteristics was demonstrated. | Mica paper is a basic component of HV insulation system. As the paper itself has a low mechanical strength to use it for stator winding insulation of HV electrical machines the reinforcement backing is required. The most widely spread reinforcing backing is glass fabric. Recently they have started to use polyester film for this purpose. The interest to polyester film is brought about by the fact that using polyester film backed mica tapes it is possible to decrease of insulation thickness as the film is at one time both a dielectric and a reinforcement material. There is some positive experience of applying film mica electrical insulation tapes for wire insulation in HV electrical motors. However to use this experience when producing main insulation for stator winding of HV electrical motor it is necessary to study the issues of polyester film stability to the exposure of long-term voltage of alternating frequency. Given below there are test results of different Resin Rich and VPI mica insulation systems made of glass fabric, polyester film and non-woven polyester paper. The tests were done on serial OAO (JSC) "Elinar Holding Company" electrical insulation mica tapes. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,968 |
In this paper we introduce a new UML stereotype, the Function Block Adapter (FBA), which is responsible for the connection of UML-RealTime capsules and function blocks of the IEC 61131-3 (standard for PLC programming languages). FBAs contain an interface to capsules as well as to function blocks and a description of the mapping between these interfaces. For this description a special FBA-language is provided. The FBA-language is easy to use both to UML-RealTime and to IEC 61131-3 developers, so they can unambiguously express the interface mapping. An important advantage of the FBA-language is the possibility of using it at an early design state of the UML-RealTime system. We explain our concept of FBAs by an application to a realistic manufacturing system. | The level of automation in factories and plants, and the need for their fast development and customization, increases steadily. Nowadays, industrial control applications are designed and implemented by exploiting various techniques and approach- es. Moreover, they are controlled by a plethora of heterogeneous embedded hard- and software systems. These factors raise the complexity of their development and the time required to conceive them. The state-of-the art and foreseen trends in engineering for the industrial automation still lack an efficient solution to circum- vent the mentioned difficulties. An undergoing European project tries to overcome this problem by an innovative component-based approach wishing to automatically link the design and implemen- tation phases of the development process. This document resumes and analyses the results of a survey conducted among the indus- trial partners of this European project. Arising is the lack of con- nection between design and implementation, particularly in terms of transformation rules. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,969 |
A number of active control systems have been developed, fabricated and installed in full-scale structures and they have been subjected to actual wind forces and ground motions. The focus of this paper is on the observed response of several of these systems. They include an active bracing system and an active mass damper system installed in a six-story experimental building, and two hybrid mass damper systems installed in two actual buildings. The configurations of these systems are summarized together with their performance characteristics. Observed performance of these systems during actual wind storms and moderate earthquakes shows that they meet their basic design objectives. Furthermore, their performance can be adequately predicted through simplified analytical and simulation procedures. | In recent years, considerable attention has been paid to research and development of passive and active structural control devices, with particular emphasis on alleviation of wind and seismie response of buildings and bridges. In both areas, serious efforts have been undertaken to develop the structural control concept into a workable technology, and today we have many such devices installed in a wide variety of structures. The focus of this state-of-the-art paper is on active, semi-active and hybrid structural control with seismic applications These systems employ controllable force devices integrated with sensors, controllers and real-time information processing. This paper includes a brief historical outline of o f their development and an assessment of the state-of-the-art and state-of-the-practice of this exciting, and still evolving, technology. Also included in the discussion are their advantages and limitations in the context of seismie design and retrofit of eivil engineering structures. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,970 |
Electrical capacitance tomography (ECT) has being widely accepted as a laboratory and industry tool to analyse gas/liquid two-phase flow. For system optimisation and function extension and for getting more information of two-phase flow, a novel extensible ECT system based on field programmable gate array (FPGA) and digital signal processor (DSP) is designed. The new scheme can easily realise not only common single-frequency excitation and demodulation but also new multi-frequency excitation and demodulation. Firstly, a review of classical ECT systems is described, and function extension of our new ECT system is introduced compared to the old ECT system in our laboratory. Then, the design scheme of the new system is proposed in detail. And main parts, such as FPGA, DSP and detection circuit are discussed one by one. Meanwhile, the generation of multi-frequency signals, discrete Fourier transform (DFT) demodulation and digital quadrature demodulation of multi-frequency are described deeply. At last, static and dynamic experiments under condition of multi-frequency excitation and demodulation are carried out to verify the performance of this novel ECT. Experimental results show that this system is of high precision and stability in multi-frequency model. And there is still a future of further extension for this ECT system. | The usage of Electrical Capacitance Tomography (ECT) is not limited to the imaging of mixtures in process equipment, it also can be used to measure the concentration profiles of component, and in certain case ECT is being used to investigate the boundaries and phase sizes within vessels and pipelines. There are quite a number of type of ECT sensors such as circular structure, square structure, concentric -annulus and parallel structure which are used for particular applications. In this paper, a study was carried out in order to investigate the behavior of electric field on the miniature parallel ECT. Simulations using COMSOL Multiphysics are being done to study the effect of increasing the size of the test object and the effect of increasing the permittivity of the test object. The results show that (1) the electric field lines relatively follow the phantom shape corresponding to the increasing of the size of the phantom and (2) the electrical field lines seems to bend more around the when the permittivity increases. Presented simulations establish first step of investigation, however already proved its usefulness for ECT performance model validation. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,971 |
The technique was developed for studying the noise immunity of electronic systems of unmanned aerial vehicles on the basis of physical modeling. The mathematical models, the scheme of a test bench, and examples of parameter calculation for physical modeling of electromagnetic interference in communication lines under the influence of switching magnetic fields of electric transport contact network are proposed. An example of physical modeling of electromagnetic interference in communication lines is presented. | The reliability of automatic control systems depends on the reliability of its elements in particular computing equipment. Computing equipment is a constant consumer of power from the network During the operation of computing technology, there are often dynamic changes in the voltage in the power supply network-dips and interruptions. Dips and interruptions are one of the main problems in terms of noise immunity of computing equipment. The results of studies of the noise immunity of computing equipment with dynamic changes in the power supply voltage are article presents. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,972 |
Though introducing the conception of “green” to optical networks, we discuss three key technologies to enhance the network energy efficiency rate (NEER), including General Multiple Protocols Label Switch (GMPLS), Passive Optical Network (PON), and Network Redundant Element Shutdown (NRES) technology. The optimization and improvement methods as well as the situation of application of the three technologies are analyzed. Then we explore the prospective development of the green optical networks. | Advances in silicon technology are failing to keep up with Internet traffic; this is unfortunate since we can envisage large bandwidth video distribution services carrying super-/ultra- high definition videos. In this context, optical technologies are critical to create bandwidth-abundant and power-efficient networks. Future networks will utilize optical paths not only for network implementation but also for the provisioning of optical circuit switching or optical flow switching services. The large throughput optical cross-connect node and optical path tunneling functions required are effectively attained with the introduction of higher order optical paths, wavebands. This technology can naturally and effectively limit the add/drop ratios of optical paths at nodes, which is very beneficial in reducing the switch hardware scale required to attain colorless, directionless, and contentionless capabilities. Harnessing the full power of light will lead to the creation of future Green networks. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,973 |
This paper presents the quantified study of the electromagnetic radiation mechanism of the 20-H rule using a numerical approach that has not yet been systematically addressed. The 20-H rule is a rule-of-thumb layout technique recommended to minimize radiated fields propagating from the edges of a printed circuit board (PCB) coupling onto nearby structures. Propagating electromagnetic fields may corrupt adjacent cable assemblies, sheet metal enclosures, and aperture openings. The magnitude of this design rule is investigated using the full-wave finite-difference time-domain (FDTD) method. An analysis on whether benefits exist from use of this rule is examined and under what conditions the rule is valid when correctly implemented. The purpose of this paper is to provide insight into the validity of the 20-H rule, recognizing that every PCB will have different simulation results. FDTD is used to capture a snapshot view of field propagation. This view allows one to determine the validity of the 20-H rule at a single point of time within a dynamic structure and what may be expected when digital components are finally added to a PCB assembly, which generally negates simulated results. | In this paper, parasitic modes, such as slotline, parallel plane, and surface wave (SW) modes, commonly found on printed circuit boards (PCBs) are analyzed and their effects on electromagnetic compatibility (EMC) and signal integrity are discussed. The analysis is based on numerical simulations using the finite difference time domain (FDTD) method which is shown to be very well suited for rigorous modeling of parasitic mode effects. The EMC and signal integrity problems discussed include power loss, crosstalk, ground bounce, and free space radiation. Design guidelines for improved EMC and signal integrity are derived from the results obtained. Comprehensive simulation and characterization of SWs using FDTD is presented for the first time. | We prove uniform local-in-time existence and uniqueness of solutions to the density-dependent magnetohydrodynamic equations. | eng_Latn | 4,974 |
Electrostatic discharge (ESD) tolerance is discussed for giant magnetoresistive (GMR) and tunneling magnetoresistive (TMR) heads within hard disk drives (HDDs). There are two kinds of testing methods for ESD: the component ESD method with Human Body Model or Machine Model and the IEC61000-4-2 testing method. The IEC61000-4-2 testing method for GMR and TMR heads within head gimbal assembly (HGA), head stack assembly (HSA), and HDD was surveyed first, and the ESD tolerance at each state of HGA, HSA, and HDD was evaluated. The equivalent circuits for three states were proposed and proved to be consistent with experimental results by the IEC61000-4-2 testing method. | In AMR/GMR heads, we find that the field emission between shield and disk is induced by the high voltage of the write driver. This paper discusses the mechanism that the noise by field emission is the current to GMR elements caused by the capacitance coupling between shield and electrode. | Background ::: The EGFR T790M mutation confers acquired resistance to kinase inhibitors in human EGFR mutant lung adenocarcinoma, is occasionally detected before treatment, and may confer genetic susceptibility to lung cancer. | eng_Latn | 4,975 |
The RF front-end is a very vulnerable part of the coupling paths that are induced by a high power electromagnetic (HPEM) pulse. Existing studies found through experiment or simulation that low-noise amplifiers (LNAs) often break down or are damaged, which causes the malfunction of the RF front-end. To protect the RF front-end, the damage process of LNAs based on theory is required in detail. This paper summarizes the damage process, and a new library is developed describing the damage phenomenon of LNAs by using user-defined elements. The model can be combined with other circuit models, and can also offer variation of the internal parameters of LNAs by HPEM pulse. Existing physical protection methods have high costs and complexity, and it is difficult to provide perfect protection. Thus, the proposed model can contribute to protection studies utilizing a circuit model. | With the minimization, intellectualization and integration of the electronic system, the radar receiving systems becomes more vulnerable to intense electromagnetic pulse (EMP). Research on the protection of radar systems against EMP weapon is very important especially in aspect of military. In this paper, the coupling modes and damage mechanism of intense EMP are analyzed; the interference effect on radar receiving system by EMP is simulated with ADS software. In the end, the measures of electromagnetic protection are proposed. | It is proved, by using topological properties, that when a group automorphism of a locally compact totally disconnected group is ergodic under the Haar measure, the group is compact. The result is an answer for Halmos's question that has remained open for the totally disconnected case. | eng_Latn | 4,976 |
Nowadays, reactive power and power factor in unbalanced circuits and/or with the presence of harmonics are still being investigated by several researchers. In this context, quaternions, whose use has recently been intensified in the electrical engineering field, is presented as an alternative tool to analyze electrical quantities in single and three-phase circuits. However, studies solving three-phase circuits by quaternions are not yet in literature, nor a complete electrical description with this tool. This article, therefore, presents single and balanced three-phase quantities expressed as quaternions. Results of an analysis of a series RLC single and balanced three-phase circuits are presented. It is important to notice that this tool can also be employed to represent three-phase power under unbalanced situations and with the presence of harmonics. | The paper demonstrates how electrical variables, when formulated as vector quaternions, can be manipulated. Circuit parameters can easily be obtained, for analytical purposes. Quaternions, which were discovered 170 years ago, are the basis for four dimensional vectors. Electrical variables fit into this realm, as some circuit variables are in quadrature with one another when viewed across different circuit components. The manipulation of the variables to obtain power, energy and impedance is shown to be simple and visual when vectors are looked at, in various planes of the four dimensional space. Other applications of quaternions and complex numbers in the general field of electrical engineering are also alluded to in the paper for completeness and in particular the famous and initial application of quaternions in electric field theory analysis by James Clerk Maxwell. | The paper demonstrates how electrical variables, when formulated as vector quaternions, can be manipulated. Circuit parameters can easily be obtained, for analytical purposes. Quaternions, which were discovered 170 years ago, are the basis for four dimensional vectors. Electrical variables fit into this realm, as some circuit variables are in quadrature with one another when viewed across different circuit components. The manipulation of the variables to obtain power, energy and impedance is shown to be simple and visual when vectors are looked at, in various planes of the four dimensional space. Other applications of quaternions and complex numbers in the general field of electrical engineering are also alluded to in the paper for completeness and in particular the famous and initial application of quaternions in electric field theory analysis by James Clerk Maxwell. | eng_Latn | 4,977 |
The wavelet method for solving the linear and quasi-linear parabolic equations under initial and boundary conditions is set out. By applying regular multi-resolution analysis and received formula for differentiating wavelet decompositions of functions of many variables the problem is reduced to a finite set of linear and accordingly nonlinear algebraic equations for the wavelet coefficients of the problem solution. The general scheme for finite-dimensional approximation in the regularization method is combined with the discrepancy principle. For quasi-linear parabolic equations the convergence rate of an approximate weak solution to a classical one is estimated. The proposed method is used for constructing stable approximate wavelet decompositions of weak solutions to boundary value problems for the unsteady porous-medium flow equation with discontinuous coefficients and inexact data. | In this work, the transient over – voltage phenomena occurred at 34.5 kV AC underground cable transmission systems during the closure of the underground cables is to be studied and simulated by using MATLAB program. Then, the transient voltage occurred at the underground cables is analyzed by using modified Fourier transform. The studied systems of underground cables are firstly modeled in frequency domain. Transient voltages induced at the sending-end and receiving-end terminals of an underground cable of transmission system are calculated in frequency domain and using inverse Fourier Transform, the sending end and receiving end voltages are obtained by converting to time domain. The effects of cable length and source impedance on transient over – voltage phenomena at underground cables are investigated. Also, the effects of GIBBS factor in transients are researched in order to eliminate GIBBS oscillations. Numerical simulations are presented to demonstrate the transient voltages induced at the terminals of sending-end and receiving-end of an underground cable at transmission system and the effects of GIBBS factor. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 4,978 |
This paper presents an electric model of a metal-oxide surge arrester (MOSA). The proposed electric model accurately represents the MOSA in a wide range of frequencies and amplitudes. The model was developed and validated based on MOSA electrical behavior in each one of the three operating regions of the zinc-oxide (ZnO) surge arresters, and in a database composed of voltage and current waveforms measured from tests performed in 12 ZnO varistors having different physical dimensions and electrical characteristics—from five different manufacturers. These varistors were subjected to different voltage levels in the low current region, and multilevel amplitude of switching current impulses (30/60 $\mu$ s), lightning current impulses (8/20 $\mu$ s), high current impulses (4/10 $\mu$ s), and fast-front current impulses (1.5/26 $\mu$ s and 3/6 $\mu$ s) encompass the three regions of operation and a wide range of frequencies and amplitudes. The results provided by the MOSA wide-range (MWR) model were compared with those obtained in the laboratory. The MWR model has shown good agreement in terms of waveform, peak value, and absorbed energy for the evaluated cases. | Measurements were performed to obtain the response of an arrester block to a steep front impulse current (1/2 /spl mu/sec), a 4/10 /spl mu/sec impulse current and a standard impulse (8/20 /spl mu/sec). As a steep front wave response model, the conventional model, the IEEE model, and a nonlinear inductance model have been studied. The method of building an arrester block model is explained in this paper. The nonlinear inductance model proposed has an accuracy of 99% in calculations of steep front impulses in block model studies. This model can be built easily and simply. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,979 |
The aim of this short note is to present the notion of IDT processes, which is a wide generalization of Levy processes obtained from a modified infinitely divisible property. Special attention is put on a number of examples, in order to clarify how much the IDT processes either differ from, or resemble to, Levy processes. | The concept of a Levy subordinator (non-decreasing paths, infinitely divisible (ID) ::: law at any point in time) is generalized to a family of non-decreasing stochastic processes ::: which are parameterized in terms of two Bernstein functions. Whereas the ::: independent increments property is only maintained in the Levy subordinator special ::: case, the considered family is always strongly infinitely divisible with respect to ::: time (IDT), meaning that a path can be represented in distribution as a finite sum ::: with arbitrarily many summands of independent and identically distributed paths ::: of another process. Besides distributional properties of the process, we present two ::: applications to the design of accurate and efficient simulation algorithms, emphasizing ::: our interest in the investigated processes. First, each member of the considered ::: family corresponds uniquely to an exchangeable max-stable sequence of random ::: variables, and we demonstrate how the associated extreme-value copula can be simulated ::: exactly and effciently from its Pickands dependence measure. Second, we ::: show how one obtains different series and integral representations for infinitely divisible ::: probability laws by varying the parameterizing pair of Bernstein functions, ::: without changing the one-dimensional law of the process. As a particular example, ::: we present an exact simulation algorithm for compound Poisson distributions from ::: the Bondesson class, for which the generalized inverse of the distribution function ::: of the associated Stieltjes measure can be evaluated accurately. | Electric vehicles (EVs) are quickly gaining widespread interest as attractive alternatives to conventional petrol driven vehicles. If EVs derive some or all of their power from renewable sources, then they can help reduce global dependence on fossil fuels for transportation. Inductive power transfer (IPT) is a method that can transfer power to EVs over an air gap without physical contact. If IPT systems are incorporated into highways, then EVs can be charged dynamically as they travel. This will dramatically increase the range, convenience and safety of EV charging as well as reduce range anxiety and battery bank capacities. One of the major difficulties involves detecting an EV as it travels along the highway. By detecting the approaching EV, the primary power supply can energize the primary IPT coupler buried in the roadway to enable contactless power transfer to the EV. A three coil detection system, which focuses on these sensor coils and which is independent of the specific IPT coupler used, is presented to allow the power supply to detect the approaching EV mounted secondary IPT coupler. The proposed detection method was tested on a laboratory scale prototype and can detect EVs approaching at different speeds, ground clearances, and horizontal misalignments. | eng_Latn | 4,980 |
In this paper we present a method for the determination of the space charge distribution, and hence the electric field distribution, in XLPE cables under an AC stress. The instrument has been developed from the well known pressure wave propagation (PWP) techniques, which have been successfully used in the study of materials under DC stress. Analysis demonstrates a high degree of confidence in the data. Data are reported, which show that statistically significant, at the 87% level, modification of the electric field due to the space charge occurs at the interfaces (in this case the semi conducting screens of the cable). The method described here will be useful for the study of high voltage AC insulation materials and structures. The technique is of particular interest for the nondestructive study of insulation ageing under AC electrification. | The space charge within oil-impregnated pressboard under AC and AC-DC combined stress were observed with a fast space charge detecting system based on the automatic equipartition phase shift (AEPS) principle. The phase resolution is about 1.79°, i. e. 201 equal division during whole period. Space charge accumulation is not distinct under AC stress at 15 kV/mm. The homocharge accumulates near ground electrode and the density decreases toward the top electrode. It may be associated with the charge injection from electrode. The amount of injected charge and the transfer distance are both depended on the electric field. Space charge accumulation is significant under AC-DC combined stress with the equal component at 15 kV/mm. The negative space charge distribution is dominant within oil-impregnated pressboard during whole period. It is mainly caused by the disruption of balance for electric field and polarization time under AC-DC stress. The polarity reversal, i.e. the voltage crossing 0 V for periodic stress, must be considered when the DC component exceeds a certain range. The space charge accumulated within oil-impregnated pressboard can distort the electric field distribution. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 4,981 |
On the feasibility of small power satellites | The problem of scaling down the size of the transmitting antenna of a solar power satellite is briefly discussed. It is shown that a multibeam Power Relay Satellite leads to smaller ground receiver stations which will improve the market penetration of power satellites. (WHK) | This article introduces the simulation procedure and results of imbalance short-circuit of electric power system based on EMTP/ATP,and provides how to turn the EMTP/ATP data to the data that Matlab can process,and the source code of the important values of U、I、P、Q、I2,etc.,needed in the electric power protection by Matlab. | eng_Latn | 4,982 |
Overcoming Interfacial Interactions with Electric Fields | Electric fields have been shown to orient nanoscopic domains laterally in thin copolymer films effectively. To achieve an orientation normal to the surface, interfacial interactions impose a barrier. Using asymmetric diblock copolymers of polystyrene (PS) and poly(methyl methacrylate) (PMMA) having cylindrical microdomains, a threshold electric field strength Et was found above which complete orientation of the cylindrical domains was achieved. This threshold field strength was independent of film thickness (for films ∼10−30 μm thick) and could be described by the difference in interfacial energies of the components. At field strengths slightly below Et a coexistence of the domains parallel and perpendicular to the electrode surface was found which is consistent with the introduction of defects via undulations in the structure as one proceeds away from the surface. | Through analysis of Qingshan Hydroelectric Power Station Lightning stroke cause,this paper puts forward the suitable lightning electromagnetic impulse protection design principle for the hydroelectric power station main control room specific protection measures aginst the surge voltage isopotential connection.Testing indicates that the protection is quite effective. | eng_Latn | 4,983 |
Numerical analysis of different pulse propagation on nonuniform transmission lines | The paper approaches the topic of the numerical modelling of the electromagnetic disturbances that occurs on HV lines. Being broadband signals, an accurate evaluation of the disturbances propagation on HV lines requires that the transmission lines model be taken into consideration. Therefore, in the first part of the paper the principles of modelling using non-uniform transmission lines are emphasized. Then the per-unit-length parameters computation is detailed, with the terms which take account of the influence of a lossy ground. In the second part of the paper the implemented numerical computation algorithm is presented. In the last part of the paper there are presented several examples using a concrete HV line to which several standard test signals have been applied. | Abstract The problem of diagnosing a fault or a perturbation in a dynamical system (be it industrial or natural) can be restated as the characterization of the transfer function of a filter that acts on a “sane” or “unperturbed” system to transform it into a “faulted” or “perturbed” one. This filter would then be approximated as time-invariant (and linear) only for short time windows, while the time evolution of such transfer function on longer time scales leads to a simple but powerful general framework that allows to diagnose the onset and/or the time evolution of a fault or perturbation of the system. | eng_Latn | 4,984 |
Intra-Vehicle Electromagnetic Compatibility Analysis. Part III. Users' Manual. | Abstract : The report contains detailed instructions for using four computer programs that comprise an electromagnetic interference analysis between avionics subsystems on aerospace vehicles. The four programs are antenna-to-antenna, wire-to-wire, electromagnetic field-to-wire, and box-to-box coupling. The programs can be run as a group to obtain a complete, analysis or separately. In this manual, extensive computer experience is not assumed, but the user should have a basic knowledge of computer usage, avionics, and electromagnetic compatibility principles. Complete information for setting up the input data, obtaining a run, and interpreting the results is given for each program. Figures defining the punched card formats for input data are provided that can be used as data sheets. The programs were written in FORTRAN IV language for the CDC 6600 computer, but they are readily adaptable to other machines. (Author) | Abstract : The report is written in answer to letters from radio amateurs asking about the impact of microelectronics on military techniques. Because the electronic equipment on rockets as well as aircraft is so bulky, various methods of miniaturization must be used. These methods, including compact mounting methods, thin film circuitry, solid state circuitry, are discussed in some detail. Included in this discussion are qualitative explanations of the construction of circuit elements in thin film and solid state devices. The subject is treated in a general way, with no hint of the type of equipment peculiar to Soviet practice. (Author) | yue_Hant | 4,985 |
Charging induced damage on complex-antenna test structures | In this paper, new complex-antenna charging test structures are designed with antennas connected to the gate, source and drain of MOS transistors, and antennas connected to both plates of the metal-insulator-metalcapacitor (MIMC) devices. The measurement results show that the transistor is free of charging when the antennas on the gate, source and drain have the same area. The failure fraction increases with the increasing of the differences in antenna size. A simple logarithm function describes very well the relation between the failure fraction of the MIMC and the ratio of the two antenna areas exposed to charging. ::: Therefore, this logarithm function can be used to anticipate charging induced damage in MIMC devices with long interconnects. | This chapter first examines how to model the impact-contact between a rigid projectile and the surface of an elastic-plastic structure and how this local behaviour interacts with the global deformation of the structure. Then, a particular type of energy-absorbing structure, namely type II, is analysed in order to explore why the deformation of such structures is sensitive to the impact velocity, or to the inertia of both the striker and the structure itself. | eng_Latn | 4,986 |
The Waipori Hydro-electric Scheme: A Heritage Perspective | The key aspects and features of the Waipori hydro-electric complex and the community aspects that led to the initiation of the project are discussed. Other developments that have taken place with the project over time are highlighted. | The paper introduces a detection and guard system based on Lon Works technology and power line carrier wave for the state of railway device box. It describes the design thought and method of the system. | eng_Latn | 4,987 |
Influence of pacing on the left ventricular electrogram in patients with ischemic cardiomyopathy: Implications for substrate mapping | a mean procedure time of 122 42 min (range 75-246 min). In 5/50 patients common atrial flutter reoccured within one month after cryoablation. Successful reablation using radiofrequency (RF) energy was performed in all of them. In 30/32 recurrence free patients, who gave final consent to invasive control stimulation, persistency of BCB was verified. In 2 patients recovery of isthmus conduction was detectable. Including the relapses 81.1% of the patients (30/37) showed persistency of BCB. Cryo applications were painless in general. No procedural complications were observed. Conclusions: Cryoablation of the CTI using the large tip catheter is feasible and safe in the treatment of common atrial flutter. Acute and short-term success rates are comparable to those reported for RF ablation. Besides short term clinical success the persistency of BCB one month after cryoablation proves efficacy of cryoablation technique. | Purpose – The purpose of this paper is to present a new pattern recognition‐based algorithm to detect high‐impedance faults (HIFs), including only with broken conductor and arcs, in distribution networks.Design/methodology/approach – In the proposed method, using discrete wavelet transform, the time‐frequency‐based features of the current waveform are calculated. Then, to extract the best feature set of the generated time‐frequency features, principle components analysis (PCA) is applied and finally support vector machines (SVM) is used as a classifier to distinguish between the HIFs, including only with broken conductor and arcs, and other similar phenomena such as capacitor banks switching, no load transformer switching, load switching, insulator leakage current and harmonic loads.Findings – The experimental results have shown that using SVM with PCA as the feature extraction method and radial basis function (RBF) as the kernel function has acceptable security and dependability performances in distingui... | eng_Latn | 4,988 |
Dual frequency active label for non-parking charge | The invention discloses a dual-frequency active label in 3.56MHz and 5.8GHz for avoiding stopping to charge. Wherein, it is formed by contact IC card read-write module, 13.56MHz read-write module, 5.8GHz radio frequency module, micro band antenna, control unit and power source manage unit; the contact IC card and 13.56MHz non-contact card are generally used in preset speedway to charge. The invention has the advantages that: it uses 5.8GHz remote RFID (radio frequency identification) technique, to realize charging without stopping vehicle, while said 3.56MHz/5.8GHz dual-frequency active electric charge label is compatible to the contact IC card and 13.56MHz non-contact card. | Abstract We report ESR experiments on a LaAl 2 sample doped with 6% Gd. The experiments were performed at 1, 3, 9 and 35 GHz. We find for T ≈ T c essentially a frequency independent shift of H res , but a frequency dependence for the minimum in the linewidth. The results will be discussed in terms of static internal fields and dynamic field fluctuations. | eng_Latn | 4,989 |
Injection-locked avalanche diode oscillator FM receiver | An injection-locked-oscillator FM receiver has been built in X-band waveguide using an avalanche diode oscillator. Measurements of the output voltage as a function of peak frequency deviation of the input signal were made and compared with theoretical values. Good agreement between theoretical and measured performance indicates that the avalanche diode is adequately described by the van der Pol model and that linear broad-band performance can be expected of the receiver. | The way to renovate the inlet/outlet differential pressure interlock protection on the boiler circulating water pump of 300 MW unit in Mawan Power Plant was discussed,as well as the effect of usage. Some approaches to extend the usage of DCS were provided. | eng_Latn | 4,990 |
Electromagnetic wave shielding fliter and method for producing the same | The present invention is a high electromagnetic wave shielding filter that can be an electromagnetic wave of a wide frequency range to be shielded by shielding ability, a porous polymer film; And it characterized in that it comprises a silver nano particles to be deposited on the surface of the porous polymer film. | Analyzing steel fiber concrete of a new type slope protection of shell structure in plain reservoir earth dam by using finite element method,effects of glacial sheet to the new type slope protection of shell structure are studied.Stress distribution of shell slope protection is carried out under various working conditions.The conclusions provide scientific basis for the optimal design of shell slope protection. | eng_Latn | 4,991 |
Magnetic thin-film media response in presence of displacement eddy currents | Experimental tests have shown that macroscopic multilayer thin films excited by high‐frequency magnetic field present permeance resonances. This unexpected behavior exists, even if the thickness of the magnetic films is smaller than the skin depth: in fact, for this condition, eddy currents within laminated magnetic sample should be inhibited. This phenomenon can be justified, observing that, for small thickness of the insulating interlayer, capacitive eddy currents across the dielectric layers begin to circulate between magnetic films. To predict the displacement eddy currents in macroscopic magnetic laminates some authors have provided various computational models based on different theoretical approaches. In particular, the computation of the effective complex permeability has been pointed out by means of coupled Maxwell’s equations, both in differential form and in an integral one. In a previous work we have proposed and validated a circuit model able to simulate the behavior of magnetic samples in th... | Purpose – To provide a general method for coupled simulation of electrical machines and circuits, using finite element analysis and a circuit/system simulator.Design/methodology/approach – The electrical machine is modelled by dynamic inductance and electromotive force (EMF), which are determined by finite element analysis and updated in time‐stepping procedure. Calculation of these parameters is based on current perturbations that are applied on linearized field equations after determining the operating point by nonlinear analysis.Findings – Based on the case studies, the presented method can be utilized in coupled field‐circuit simulation and the results correlate with those obtained by other known methods. The results were also validated according to experimental data.Research limitations/implications – Calculation of the EMF and the presented implementation for SIMULINK have some limitations regarding the accuracy and stability of the numerical integration. In the future, the numerical methods could b... | eng_Latn | 4,992 |
Study on Distribution Characteristics of Electromagnetic Pollution at Typical 500 kV Substation in Liaoning Province,China | In order to understand 500 kV substation electromagnetic pollution distribution characteristics,EFA-300 electromagnetic field strength analyzer was used to measure the power frequency electric field intensity and magnetic field strength in different regions,including 500 kV area,220 kV area,main equipments area and surrounding area.The results of 92 measurement points showed that all data from the measurement were allowed by the standard.However,the electric field intensity around certain equipments almost reached occupational standard limits,which should pay more attention in precaution. | In this paper we discuss the approximations introduced in the average-ion model usually employed for level population calculations. An improved system of equations of higher-order approximation is given. It is proved that in electric dipole approximation the level population probability Pnlj is independent of the quantum number j. leading to a great reduction of the number of equations to be solved. Finally, a method feasible for calculating these rate equations is suggested. | eng_Latn | 4,993 |
Power supply analysis in package and SiP design | This paper introduces a process that allows customers to do package power integrity (PI) analysis on the package side. The chip information such as the die circuits and current profiles as well as power delivery network circuit can be used at the board level to perform PI analysis. The die current profiles are used to obtain the target impedance. For the complicated package geometry structure, the 3D electromagnetic field solver is used to extract the package power supply model. In order to meet the target impedance, the required decoupling capacitors and location can be analyzed and placed according to the transfer impedance in frequency domain. The user can use the voltage ripples in time domain on power and ground nets for a direct verification process. | This paper explains the way how to use the opto-coupler of interface grade with SPI bus in the control system in order to strengthen the noise rejection feature of the system. | eng_Latn | 4,994 |
A REVIEW OF THE =SITE DIELEmIC INSULATED UNDERGROUND TkANSMISSION CABLE | Oil-impregnated paper-insulatedh igh v oltage cables have proven to be the most rugged and reliable underground systems for electrical power transmission. The increasing need for transmitting largerblocksof power intorapidly expanding urban areas has focused the attention on the advantages of systems operating at higher v oltages.The increase of insulationwallthicknesswithh'igher voltage levels and prohibitivelyhighdieleetriclossesassociated with it however, limit the transmissionsyst emcapability significantly i ncreasingtheove rall cost of the operation. The economicbenefitswitheasein handling of cables with areduced sizehasstimulate d anintensive research towards substitutingthe traditional oil-paper insulation forthe purpose of improving efficiency and capacity in underground transmissionsystemswithouttheuse of forced c ooling or higher oil pressures. | RECEIVING STATION FOR REDUCING A SINGLE CONTROL DEVICE AUTOMATIC TO TREAT DIFFERENT TELEVISION CHANNELS. SHE HAS A PLATINUM CAG UNIQUE IN WHICH THERE IS A LOCAL OSCILLATOR CONTROL VOLTAGE FREQUENCY VARIANT cyclically BASED ON ANALYSIS OF LEVEL OF CARRIER APPLICATION:.. TELEDISTRIBUTION | yue_Hant | 4,995 |
Design and Implementation of EMC Prediction System of Ship Formation | To make the carrier-borne electronic equipments working together without interference to exert completely the efficiency of combat system at sea,electromagnetic compatibility (EMC) of the whole ship formation should be guaranteed.The design of the ship formation electromagnetic compatibility prediction system was introduced,and the system architecture was analyzed.The working mechanism of each module and the calculating flow of electromagnetic interference (EMI) prediction were emphasized.Finally,it was demonstrated with case analysis that the system can accomplish the electromagnetic compatibility prediction task on ship formation. | In this article we will show you how to carry out the water charging system,used in LAN,including it's main structure,designing conception as well as the key technology to solve several problems we met.We emphasized the way to realize a Client/Server structured MIS based on DB.Finally we will tell you how to carry out this system,which is developed in C++Builder IDE,in detail. | eng_Latn | 4,996 |
Feasibility Simulation Research on Detecting Cerebral Haematoma Based on Dielectric Property | Aimed at detecting the haematoma as well as development expediently, a capacitance measuring method detection based on dielectric property is presented through analyzing the changing regularity of the conductivity and permittivity of the head tissue at different frequency. According to the head structure, a mutli-layer brain model is built up with ANSYS analysis software. The different states of haematoma such as the position, size and the extent of approaching the measuring electrode are analyzed in two-dimension model. The feasibility of the measurement is proved, and the further research is established. | Abstract : These notes are primarily intended as a guide for the individual attending the DNA EMP Awareness Course. The text serves as an engineering introduction to the EMP systems design problem and provides a survey of techniques suitable for solving this hardening problem. The text discusses all aspects of EMP, from the environment through system design and testing. (Author) | eng_Latn | 4,997 |
Design of Integrated Low-Power Irrigation Monitoring Terminal | In order to realize low-cost automatic control of field irrigation and water metering, an integrated low-power irrigation monitoring terminal based on wireless data communication was designed. Powered by battery or solar, the terminal could acquire and store data of sensors and water meters in real-time. Taking valve as control object, the terminal can provide safe irrigation strategy based on multiple control logic, such as data overrun, time and manual operation. The detection of fault on-site and reasonable judgment of irrigation can be carried out by using self-check function, querying of local data and remote data transmission based on GPRS and Modbus Protocol. Experimental results showed that the terminal could work stably, and control irrigation water usage accurately with low power cost. | This article through 2604 working face floor to probe bottom water of mine transient in Wangcun Coal Mine,analysed the advantages of transient electromagnetic methodof theoretically,and etting observation point through 2604 face,using Terra TEM transient electromagnetic instrument for observation,through on-site practice to explain this reasonable and accuracy method.Therefore,by transient electromagnetic method in the prediction of bottom water has good application value. | eng_Latn | 4,998 |
Transfer Impedance Measurement of Shielded Cables Through Localized Injection | This letter presents a method to determine experimentally the transfer impedance of electrically short shielded cables up to 100 or 150 MHz (depending on the cable length). The proposed method aims to create a disturbance along the cable shield with a localized injection device as for instance a toroidal magnetic probe. Two different experimental setups referred as “scalar” and “vectorial” setups are proposed. The validations are performed on cables of known transfer impedance with respect to other experimental techniques and theoretical formulations. The presented results exhibit the advantages and drawbacks of both setups with respect to the existing experimental methods. | Objective To fully realize laboratory information sharing, giving full play of automation and intellectualization of laboratory devices and improving the management level and work efficiency. Methods A new network architecture method was adopted. The laboratory devices were connected by joining TS into the master network. A computer installing interface management program was used as device server. All laboratory instruments were managed by the interface management program. Results The new LIS realized the total inosculation of LIS and HIS and the connection method of different communication modes on many serial communication devices. Conclusion The method strengthens the system's network integration. The maintenance costs and PC resources are saved. | eng_Latn | 4,999 |
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