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train_1652 | Convergence of a finite volume scheme for nonlinear degenerate parabolic | equations One approximates the entropy weak solution u of a nonlinear parabolic degenerate equation u/sub t/+div(qf(u))- Delta phi (u)=0 by a piecewise constant function u/sub D/ using a discretization D in space and time and a finite volume scheme. The convergence of u/sub D/ to u is shown as the size of the space and time steps tend to zero. In a first step, estimates on u/sub D/ are used to prove the convergence, up to a subsequence, of u/sub D/ to a measure valued entropy solution (called here an entropy process solution). A result of uniqueness of the entropy process solution is proved, yielding the strong convergence of u/sub D/ to u. Some numerical results on a model equation are shown | finite volume scheme;numerical results;model equation;piecewise constant function;nonlinear degenerate parabolic equations;entropy weak solution;strong convergence |
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train_1653 | The best circulant preconditioners for Hermitian Toeplitz systems.II. The | multiple-zero case For pt.I. see SIAM J. Numer. Anal., vol. 38, p. 876-896. Circulant-type preconditioners have been proposed previously for ill-conditioned Hermitian Toeplitz systems that are generated by nonnegative continuous functions with a zero of even order. The proposed circulant preconditioners can be constructed without requiring explicit knowledge of the generating functions. It was shown that the spectra of the preconditioned matrices are uniformly bounded except for a fixed number of outliers and that all eigenvalues are uniformly bounded away from zero. Therefore the conjugate gradient method converges linearly when applied to solving the circulant preconditioned systems. Previously it was claimed that this result can be extended to the case where the generating functions have multiple zeros. The main aim of this paper is to give a complete convergence proof of the method for this class of generating functions | generating functions;conjugate gradient method;nonnegative continuous functions;hermitian toeplitz systems;multiple-zero case;circulant preconditioners;preconditioned matrices;eigenvalues |
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train_1654 | Numerical validation of solutions of complementarity problems: the nonlinear | case This paper proposes a validation method for solutions of nonlinear complementarity problems. The validation procedure performs a computational test. If the result of the test is positive, then it is guaranteed that a given multi-dimensional interval either includes a solution or excludes all solutions of the nonlinear complementarity problem | nonlinear complementarity problem;optimization;computational test;numerical validation |
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train_1655 | An empirical investigation of the influences of the degree of interactivity on | user-outcomes in a multimedia environment The study reported here investigates the influence of "interactivity" on the learning outcomes of users in a multimedia systems environment. Drawing from past literature base and based on key tenets of three learning theories - behaviorist, cognitivist, and constructivist - the study first proposes a measurement scheme for "interactivity" and then hypothesizes that "interactivity" would influence the learning outcomes positively in terms of users' learning achievement and attitude. Three prototypes of a multimedia instructional/training system to represent high, low, and noninteractive modes of use were developed and implemented and the hypothesized influences were investigated using a controlled laboratory research design. Multiple analysis of variance (MANOVA) results indicate that while interactivity does not necessarily enable enhanced gain in user learning, it positively influences participants' attitude. The study finds no support for hypothesized moderating effects of learning styles (measured using Kolb's Learning Style Inventory scale) on the relationship between interactivity and user outcomes. The results of this study have important implications for both education and corporations' training efforts and investments. Implications and future research directions are discussed | measurement scheme;multiple analysis of variance;training system;interactivity;multimedia systems environment;cognitivist learning theories;manova;behaviorist learning theories;corporations;user outcomes;user attitude;constructivist learning theories;learning outcomes;kolb learning style inventory scale;education |
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train_1656 | Impact of user satisfaction and trust on virtual team members | Pressured by the growing need for fast response times, mass customization, and globalization, many organizations are turning to flexible organizational forms, such as virtual teams. Virtual teams consist of cooperative relationships supported by information technology to overcome limitations of time and/or location. Virtual teams require their members to rely heavily on the use of information technology and trust in coworkers. This study investigates the impacts that the reliance on information technology (operationalized in our study via the user satisfaction construct) and trust have on the job satisfaction of virtual team members. The study findings reveal that both user satisfaction and trust are positively related to job satisfaction in virtual teams, while system use was not found to play a significant role. These findings emphasize that organizations seeking the benefits of flexible, IT-enabled virtual teams must consider both the level of trust among colleagues, and the users' satisfaction with the information technology on which virtual teams rely | information technology;job satisfaction;it;virtual team members;user satisfaction;trust |
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train_1657 | Breaking the myths of rewards: an exploratory study of attitudes about | knowledge sharing Many CEO and managers understand the importance of knowledge sharing among their employees and are eager to introduce the knowledge management paradigm in their organizations. However little is known about the determinants of the individual's knowledge sharing behavior. The purpose of this study is to develop an understanding of the factors affecting the individual's knowledge sharing behavior in the organizational context. The research model includes various constructs based on social exchange theory, self-efficacy, and theory of reasoned action. Research results from the field survey of 467 employees of four large, public organizations show that expected associations and contribution are the major determinants of the individual's attitude toward knowledge sharing. Expected rewards, believed by many to be the most important motivating factor for knowledge sharing, are not significantly related to the attitude toward knowledge sharing. As expected, positive attitude toward knowledge sharing is found to lead to positive intention to share knowledge and, finally, to actual knowledge sharing behaviors | self-efficacy;social exchange theory;strategic management;rewards;public organizations;theory of reasoned action;knowledge management;knowledge sharing |
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train_1658 | Chaos theory as a framework for studying information systems | This paper introduces chaos theory as a means of studying information systems. It argues that chaos theory, combined with new techniques for discovering patterns in complex quantitative and qualitative evidence, offers a potentially more substantive approach to understand the nature of information systems in a variety of contexts. The paper introduces chaos theory concepts by way of an illustrative research design | qualitative evidence;complex quantitative evidence;pattern discovery;chaos theory;information systems |
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train_1659 | Mobile commerce: transforming the vision into reality | This editorial preface investigates current developments in mobile commerce (M-commerce) and proposes an integrated architecture that supports business and consumer needs in an optimal way to successfully implement M-commerce business processes. The key line of thought is based on the heuristic observation that customers will not want to receive M-commerce offerings to their mobile telephones. As a result, a pull as opposed to a push approach becomes a necessary requirement to conduct M-commerce. In addition, M-commerce has to rely on local, regional, demographic and many other variables to be truly effective. Both observations necessitate an M-commerce architecture that allows the coherent integration of enterprise-level systems as well as the aggregation of product and service offerings from many different and partially competing parties into a collaborative M-commerce platform. The key software component within this integrated architecture is an event management engine to monitor, detect, store, process and measure information about outside events that are relevant to all participants in M-commerce | consumer needs;business needs;integrated architecture;collaborative platform;mobile telephones;pull approach;event management engine;mobile commerce;m-commerce |
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train_166 | The semantic Web: differentiating between taxonomies and ontologies | There is a new vision of the WWW - the semantic Web - that will dramatically improve Web-based services and products. It creates a setting where software agents perform everyday jobs for end-users. Deploying hierarchies, metadata, and structured vocabularies, the semantic Web expands basic Internet functions | internet;metadata;structured vocabularies;hierarchies;software agents;semantic web;www |
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train_1660 | A regularized conjugate gradient method for symmetric positive definite system | of linear equations A class of regularized conjugate gradient methods is presented for solving the large sparse system of linear equations of which the coefficient matrix is an ill-conditioned symmetric positive definite matrix. The convergence properties of these methods are discussed in depth, and the best possible choices of the parameters involved in the new methods are investigated in detail. Numerical computations show that the new methods are more efficient and robust than both classical relaxation methods and classical conjugate direction methods | ill-conditioned linear system;convergence properties;symmetric positive definite system;linear equations;regularized conjugate gradient method;classical conjugate direction methods;coefficient matrix;large sparse system;classical relaxation methods |
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train_1661 | The road to perpetual progress [retail inventory management] | With annual revenues increasing 17.0% to 20.0% consistently over the last three years and more than 2,500 new stores opened from 1998 through 2001, Dollar General is on the fast track. However, the road to riches could have easily become the road to ruin had the retailer not exerted control over its inventory management | dollar general;retailer;inventory management |
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train_1663 | VSAT technology aids growth | Choosing to migrate to IP-based applications also means deciding whether terrestrial technologies such as frame relay, DSL or "plain old telephone service" (POTS) can provide the scalability, flexibility and high bandwidth required to support those applications, and whether these technologies can do so affordably. Each option has its tradeoffs. Also, in each case, retailers with nationwide chains have to deal with multiple last-mile service providers for service installation and network maintenance. Because of this, many retailers are selecting two-way satellite networking technology (frequently referred to as VSAT) as the technology of choice for always-on, nationwide, high-speed connectivity coupled with end-to-end network ownership and favorable economics. Enterprises are adopting VSAT platforms not only for emerging IP and Web-based applications, but also for mission-critical, front-office functions such as credit authorization and point-of-sale polling | vsat;ip-based applications;retailers |
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train_1664 | Disappointment reigns [retail IT] | CPFR remains at the forefront of CIOs' minds, but a number of barriers, such as secretive corporate cultures and spotty data integrity, stand between retail organizations and true supply-chain collaboration. CIOs remain vexed at these obstacles, as was evidenced at a roundtable discussion by retail and consumer-goods IT leaders at the Retail Systems 2002 conference, held in Chicago by the consultancy MoonWatch Media Inc., Newton Upper Falls, Mass. Other annoyances discussed by retail CIOs include poorly designed business processes and retail's poor image with the IT talent emerging from school into the job market | moonwatch media;cios;collaborative planning forecasting and replenishment;retail;retail systems 2002 conference |
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train_1665 | How airlines and airports recover from schedule perturbations: a survey | The explosive growth in air traffic as well as the widespread adoption of Operations Research techniques in airline scheduling has given rise to tight flight schedules at major airports. An undesirable consequence of this is that a minor incident such as a delay in the arrival of a small number of flights can result in a chain reaction of events involving several flights and airports, causing disruption throughout the system. This paper reviews recent literature in the area of recovery from schedule disruptions. First we review how disturbances at a given airport could be handled, including the effects of runways and fixes. Then we study the papers on recovery from airline schedule perturbations, which involve adjustments in flight schedules, aircraft, and crew. The mathematical programming techniques used in ground holding are covered in some detail. We conclude the review with suggestions on how singular perturbation theory could play a role in analyzing disruptions to such highly sensitive schedules as those in the civil aviation industry | recovery;flight schedule adjustments;airports;ground holding;aircraft adjustments;disturbance handling;singular perturbation theory;schedule perturbation;crew adjustments;runways;operations research techniques;schedule disruptions;mathematical programming techniques;airline scheduling;air traffic management;civil aviation industry;tight flight schedules |
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train_1666 | Airline base schedule optimisation by flight network annealing | A system for rigorous airline base schedule optimisation is described. The architecture of the system reflects the underlying problem structure. The architecture is hierarchical consisting of a master problem for logical aircraft schedule optimisation and a sub-problem for schedule evaluation. The sub-problem is made up of a number of component sub-problems including connection generation, passenger choice modelling, passenger traffic allocation by simulation and revenue and cost determination. Schedule optimisation is carried out by means of simulated annealing of flight networks. The operators for the simulated annealing process are feasibility preserving and form a complete set of operators | simulated annealing;passenger traffic allocation;cost determination;operators;hierarchical architecture;passenger choice modelling;airline base schedule optimisation;flight network annealing;master problem;system architecture;time complexity;schedule evaluation;logical aircraft schedule optimisation;connection generation |
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train_1667 | Combining constraint programming and linear programming on an example of bus | driver scheduling Provides details of a successful application where the column generation algorithm was used to combine constraint programming and linear programming. In the past, constraint programming and linear programming were considered to be two competing technologies that solved similar types of problems. Both these technologies had their strengths and weaknesses. The paper shows that the two technologies can be combined together to extract the strengths of both these technologies. Details of a real-world application to optimize bus driver duties are given. This system was developed by ILOG for a major software house in Japan using ILOG-Solver and ILOG-CPLEX, constraint programming and linear programming C/C++ libraries | linear programming;ilog;constraint programming;ilog-cplex;column generation algorithm;ilog-solver;c/c++ libraries;bus driver scheduling |
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train_1668 | Elastic constraint branching, the Wedelin/Carmen Lagrangian heuristic and | integer programming for personnel scheduling The Wedelin algorithm is a Lagrangian based heuristic that is being successfully used by Carmen Systems to solve large crew pairing problems within the airline industry. We extend the Wedelin approach by developing an implementation for personnel scheduling problems (also termed staff rostering problems) that exploits the special structure of these problems. We also introduce elastic constraint branching with the twin aims of improving the performance of our new approach and making it more column generation friendly. Numerical results show that our approach can outperform the commercial solver CPLEX on difficult commercial rostering problems | lagrangian based heuristic;column generation friendly approach;integer programming;personnel scheduling;airline industry;large crew pairing problems;staff rostering problems;elastic constraint branching;wedelin algorithm;carmen systems |
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train_1669 | Supply chain optimisation in the paper industry | We describe the formulation and development of a supply-chain optimisation model for Fletcher Challenge Paper Australasia (FCPA). This model, known as the paper industry value optimisation tool (PIVOT), is a large mixed integer program that finds an optimal allocation of supplier to mill, product to paper machine, and paper machine to customer, while at the same time modelling many of the supply chain details and nuances which are peculiar to FCPA. PIVOT has assisted FCPA in solving a number of strategic and tactical decision problems, and provided significant economic benefits for the company | tactical decision problems;paper industry value optimisation tool;supply chain optimisation;strategic decision problems;economic benefits;pivot;optimal allocation;large mixed integer program;fletcher challenge paper australasia |
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train_167 | Business school research: bridging the gap between producers and consumers | There has been a great deal of continuing discussion concerning the seemingly unbridgeable gap between so much of the research produced by business school professors and the needs of the business people who, ideally, would use it. Here, we examine this gap and suggest a model for bridging it. We sample four groups of people, business school academics (professors), deans of business schools, executive MBA students/recent graduates, and senior business executives. Each group rates 44 different (potential) properties of exemplary research. We analyze within-group differences, and more meaningfully, between-group differences. We then offer commentary on the results and use the results to develop the aforementioned suggestions for bridging the gap we find | within-group differences;recent graduates;producers;exemplary research;coefficient of concordance;multiple comparison testing;business school;anova;academics;business people;professors;between-group differences;deans;students;senior business executives;consumers |
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train_1670 | An integrated optimization model for train crew management | Train crew management involves the development of a duty timetable for each of the drivers (crew) to cover a given train timetable in a rail transport organization. This duty timetable is spread over a certain period, known as the roster planning horizon. Train crew management may arise either from the planning stage, when the total number of crew and crew distributions are to be determined, or from the operating stage when the number of crew at each depot is known as input data. In this paper, we are interested in train crew management in the planning stage. In the literature, train crew management is decomposed into two stages: crew scheduling and crew rostering which are solved sequentially. We propose an integrated optimization model to solve both crew scheduling and crew rostering. The model enables us to generate either cyclic rosters or non-cyclic rosters. Numerical experiments are carried out over data sets arising from a practical application | cyclic rosters;integer programming;crew scheduling;rail transport organization;noncyclic rosters;train crew management;duty timetable;integrated optimization model;crew rostering;roster planning horizon |
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train_1671 | Cane railway scheduling via constraint logic programming: labelling order and | constraints in a real-life application In Australia, cane transport is the largest unit cost in the manufacturing of raw sugar, making up around 35% of the total manufacturing costs. Producing efficient schedules for the cane railways can result in significant cost savings. The paper presents a study using constraint logic programming (CLP) to solve the cane transport scheduling problem. Tailored heuristic labelling order and constraints strategies are proposed and encouraging results of application to several test problems and one real-life case are presented. The preliminary results demonstrate that CLP can be used as an effective tool for solving the cane transport scheduling problem, with a potential decrease in development costs of the scheduling system. It can also be used as an efficient tool for rescheduling tasks which the existing cane transport scheduling system cannot perform well | total manufacturing costs;heuristic labelling order;cane transport;cost savings;cane railway scheduling;constraints strategies;constraint logic programming;raw sugar |
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train_1672 | Two issues in setting call centre staffing levels | Motivated by a problem facing the Police Communication Centre in Auckland, New Zealand, we consider the setting of staffing levels in a call centre with priority customers. The choice of staffing level over any particular time period (e.g., Monday from 8 am-9 am) relies on accurate arrival rate information. The usual method for identifying the arrival rate based on historical data can, in some cases, lead to considerable errors in performance estimates for a given staffing level. We explain why, identify three potential causes of the difficulty, and describe a method for detecting and addressing such a problem | nonstationarity;arrival rate information;new zealand;conditional poisson process;priority customers;forecast error;performance estimates;call centre staffing levels;police communication centre;auckland |
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train_1673 | Mission planning for regional surveillance | The regional surveillance problem discussed involves formulating a flight route for an aircraft to scan a given geographical region. Aerial surveillance is conducted using a synthetic aperture radar device mounted on the aircraft to compose a complete, high-resolution image of the region. Two models for determining an optimised flight route are described, the first employing integer programming and the second, genetic algorithms. A comparison of the solution optimality in terms of the total distance travelled, and model efficiency of the two techniques in terms of their required CPU times, is made in order to identify the conditions under which it is appropriate to apply each model | synthetic aperture radar device;flight route;integer programming;high-resolution image;total distance travelled;mission planning;genetic algorithms;geographical region scanning;regional surveillance;aerial surveillance;optimised flight route;solution optimality |
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train_1674 | A column generation approach to delivery planning over time with inhomogeneous | service providers and service interval constraints We consider a problem of delivery planning over multiple time periods. Deliveries must be made to customers having nominated demand in each time period. Demand must be met in each time period by use of some combination of inhomogeneous service providers. Each service provider has a different delivery capacity, different cost of delivery to each customer, a different utilisation requirement, and different rules governing the spread of deliveries in time. The problem is to plan deliveries so as to minimise overall costs, subject to demand being met and service rules obeyed. A natural integer programming model was found to be intractable, except on problems with loose demand constraints, with gaps between best lower bound and best feasible solution of up to 35.1%, with an average of 15.4% over the test data set. In all but the problem with loosest demand constraints, Cplex 6.5 applied to this formulation failed to find the optimal solution before running out of memory. However a column generation approach improved the lower bound by between 0.6% and 21.9%, with an average of 9.9%, and in all cases found the optimal solution at the root node, without requiring branching | inhomogeneous service providers;service interval constraints;transportation;delivery planning over time;delivery capacity;column generation approach;lower bound |
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train_1675 | An operations research approach to the problem of the sugar cane selection | Selection for superior clones is the most important aspect of sugar cane improvement programs, and is a long and expensive process. While studies have investigated different components of selection independently, there has not been a whole system approach to improve the process. This study observes the problem as an integrated system, where if one parameter changes the state of the whole system changes. A computer based stochastic simulation model that accurately represents the selection was developed. The paper describes the simulation model, showing its accuracy as well as how a combination of dynamic programming and branch and bound can be applied to the model to optimise the selection system, giving a new application of these techniques. The model can be directly applied to any region targeted by sugar cane breeding programs or to other clonally propagated crops | clonally propagated crops;sugar cane selection;improvement programs;operations research approach;branch and bound;agriculture;computer based stochastic simulation model;dynamic programming;superior clones;breeding programs |
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train_1676 | An optimization based approach to the train operator scheduling problem at | Singapore MRT Singapore Mass Rapid Transit (SMRT) operates two train lines with 83 kilometers of track and 48 stations. A total of 77 trains are in operation during peak hours and 41 during off-peak hours. We report on an optimization based approach to develop a computerized train-operator scheduling system that has been implemented at SMRT. The approach involves a bipartite matching algorithm for the generation of night duties and a tabu search algorithm for the generation of day duties. The system automates the train-operator scheduling process at SMRT and produces favorable schedules in comparison with the manual process. It is also able to handle the multiple objectives inherent in the crew scheduling system. While trying to minimize the system wide crew-related costs, the system is also able to address concern with respect to the number of split duties | computerized train-operator scheduling system;optimization based approach;crew scheduling system;bipartite matching algorithm;day duties;tabu search algorithm;night duties;singapore mass rapid transit |
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train_1677 | Minimised geometric Buchberger algorithm for integer programming | Recently, various algebraic integer programming (IP) solvers have been proposed based on the theory of Grobner bases. The main difficulty of these solvers is the size of the Grobner bases generated. In algorithms proposed so far, large Grobner bases are generated by either introducing additional variables or by considering the generic IP problem IP/sub A,C/. Some improvements have been proposed such as Hosten and Sturmfels' method (GRIN) designed to avoid additional variables and Thomas' truncated Grobner basis method which computes the reduced Grobner basis for a specific IP problem IP/sub A,C/(b) (rather than its generalisation IPA,C). In this paper we propose a new algebraic algorithm for solving IP problems. The new algorithm, called Minimised Geometric Buchberger Algorithm, combines Hosten and Sturmfels' GRIN and Thomas' truncated Grobner basis method to compute the fundamental segments of an IP problem IP/sub A,C/ directly in its original space and also the truncated Grobner basis for a specific IP problem IP/sub A,C/ (b). We have carried out experiments to compare this algorithm with others such as the geometric Buchberger algorithm, the truncated geometric Buchberger algorithm and the algorithm in GRIN. These experiments show that the new algorithm offers significant performance improvement | reduced grobner basis;algebraic integer programming;minimised geometric buchberger algorithm;truncated grobner basis method;truncated geometric buchberger algorithm;performance improvement;grin algorithm;geometric buchberger algorithm;fundamental segments;grobner bases |
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train_1678 | Parallel interior point schemes for solving multistage convex programming | The predictor-corrector interior-point path-following algorithm is promising in solving multistage convex programming problems. Among many other general good features of this algorithm, especially attractive is that the algorithm allows the possibility to parallelise the major computations. The dynamic structure of the multistage problems specifies a block-tridiagonal system at each Newton step of the algorithm. A wrap-around permutation is then used to implement the parallel computation for this step | multistage convex programming;parallel computation;block-tridiagonal system;dynamic structure;parallel interior point schemes;wrap-around permutation;predictor-corrector interior-point path-following algorithm;newton step |
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train_1679 | Project scheduling under time dependent costs-a branch and bound algorithm | In a given project network, execution of each activity in normal duration requires utilization of certain resources. If faster execution of an activity is desired then additional resources at extra cost would be required. Given a project network, the cost structure for each activity and a planning horizon, the project compression problem is concerned with the determination of optimal schedule of performing each activity while satisfying given restrictions and minimizing the total cost of project execution. The paper considers the project compression problem with time dependent cost structure for each activity. The planning horizon is divided into several regular time intervals over which the cost structure of an activity may vary. But the cost structure of the activities remains the same within a time interval. The objective is to find an optimal project schedule minimizing the total project cost. We present a mathematical model for this problem, develop some heuristics and an exact branch and bound algorithm. Using simulated problems we provide an insight into the computational performances of heuristics and the branch and bound algorithm | planning horizon;project scheduling;branch and bound algorithm;optimal schedule;project network;heuristics;time dependent costs;project compression problem |
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train_168 | Nurturing clients' trust to encourage engagement success during the | customization of ERP systems Customization is a crucial, lengthy, and costly aspect in the successful implementation of ERP systems, and has, accordingly, become a major specialty of many vendors and consulting companies. The study examines how such companies can increase their clients' perception of engagement success through increased client trust that is brought about through responsive and dependable customization. Survey data from ERP customization clients show that, as hypothesized, clients' trust influenced their perception of engagement success with the company. The data also show that clients' trust in the customization company was increased when the company behaved in accordance with client expectations by being responsive, and decreased when the company behaved in a manner that contradicted these expectations by not being dependable. Responses to an open-ended question addendum attached to the survey corroborated the importance of responsiveness and dependability. Implications for customization companies and research on trust are discussed | integrity;perceived responsiveness;enterprise resource planning systems;customization;vendors;dependability;engagement success;client trust;erp systems;consulting companies;mrp ii implementation;benevolence |
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train_1680 | Minimizing weighted number of early and tardy jobs with a common due window | involving location penalty Studies a single machine scheduling problem to minimize the weighted number of early and tardy jobs with a common due window. There are n non-preemptive and simultaneously available jobs. Each job will incur an early (tardy) penalty if it is early (tardy) with respect to the common due window under a given schedule. The window size is a given parameter but the window location is a decision variable. The objective of the problem is to find a schedule that minimizes the weighted number of early and tardy jobs and the location penalty. We show that the problem is NP-complete in the ordinary sense and develop a dynamic programming based pseudo-polynomial algorithm. We conduct computational experiments, the results of which show that the performance of the dynamic algorithm is very good in terms of memory requirement and CPU time. We also provide polynomial time algorithms for two special cases | pseudo-polynomial algorithm;np-complete problem;tardy jobs;common due window;single machine scheduling problem;decision variable;dynamic programming;early jobs;location penalty |
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train_1681 | One and two facility network design revisited | The one facility one commodity network design problem (OFOC) with nonnegative flow costs considers the problem of sending d units of flow from a source to a destination where arc capacity is purchased in batches of C units. The two facility problem (TFOC) is similar, but capacity can be purchased either in batches of C units or one unit. Flow costs are zero. These problems are known to be NP-hard. We describe an exact O(n/sup 3/3/sup n/) algorithm for these problems based on the repeated use of a bipartite matching algorithm. We also present a better lower bound of Omega (n/sup 2k*/) for an earlier Omega (n/sup 2k/) algorithm described in the literature where k = [d/C] and k* = min{k, [(n 2)/2]}. The matching algorithm is faster than this one for k >or= [(n - 2)/2]. Finally, we provide another reformulation of the problem that is quasi integral. This property could be useful in designing a modified version of the simplex method to solve the problem using a sequence of pivots with integer extreme solutions, referred to as the integral simplex method in the literature | np-hard problems;flow costs;bipartite matching algorithm;integral simplex method;one facility one commodity network design problem;exact algorithm;nonnegative flow costs;pivots;lower bound;quasi integral;two facility network design |
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train_1682 | Data mining efforts increase business productivity and efficiency | The use and acquisition of information is a key part of the way any business makes money. Data mining technologies provide greater insight into how this information can be better used and more effectively acquired. Steven Kudyba, an expert in the field of data mining technologies, shares his expertise in an interview | productivity;efficiency;data mining |
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train_1683 | Unlocking the potential of videoconferencing | I propose in this paper to show, through a number of case studies, that videoconferencing is user-friendly, cost-effective, time-effective and life-enhancing for people of all ages and abilities and that it requires only a creative and imaginative approach to unlock its potential. I believe that these benefits need not, and should not, be restricted to the education sector. My examples will range from simple storytelling, through accessing international experts, professional development and distance learning in a variety of forms, to the use of videoconferencing for virtual meetings and planning sessions. In some cases, extracts from the reactions and responses of the participants will be included to illustrate the impact of the medium | videoconferencing;education;case studies;benefits |
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train_1684 | E-learning on the college campus: a help or hindrance to students learning | objectives: a case study If you know how to surf the World Wide Web, have used email before, and can learn how to send an email attachment, then learning how to interact in an online course should not be difficult at all. In a way to find out, I decided to offer two identical courses, one of which would be offered online and the other the "traditional way". I wanted to see how students would fare with identical material provided in each course. I wanted their anonymous feedback, when the course was over | e-learning;distance education;william paterson university |
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train_1685 | Use of web technologies in construction project management: what are the | critical success/failure factors? A concept of how the World Wide Web (WWW) and its associated technologies can be used to manage construction projects has been recognized by practitioners in the construction industry for quite sometime. This concept is often referred to as a Web-Based Project Management System (WPMS). It promises, to enhance construction project documentation and control, and to revolutionize the way construction project teams process and transmit project information. WPMS is an electronic project-management system conducted through the Internet. The system provides a centralized, commonly accessible, reliable means of transmitting and storing project information. Project information is stored on the server and a standard Web browser is used as the gateway to exchange this information, eliminating geographic and hardware platforms boundary | implementation;construction industry;web-based project management system;web browser;success;project control;project documentation |
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train_1686 | Internet infrastructure and the emerging information society: an appraisal of | the Internet backbone industry This paper examines the real constraints to the expansion of all encumbering and all pervasive information technology in our contemporary society. Perhaps the U.S. Internet infrastructure is the most appropriate to examine since it is U.S. technology that has led the world into the Internet age. In this context, this paper reviews the state of the U.S. Internet backbone that will lead us into information society of the future by facilitating massive data transmission | internet service providers;backbone companies;local telephone companies;users;internet infrastructure |
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train_1687 | Cleared for take-off [Hummingbird Enterprise] | A recent Gartner report identifies Hummingbird in the first wave of vendors as an early example of convergence in the 'smart enterprise suite' market. We spoke to Hummingbird's Marketing Director for Northern Europe | smart enterprise suite;hummingbird enterprise;information content;collaboration;knowledge content |
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train_1688 | Connecting the business without busting the budget | The "multi-channel content delivery" model (MCCD) might be a new concept to you, but it is already beginning to replace traditional methods of business communications, print and content delivery, argues Darren Atkinson, CTO, FormScape | content management;business process management;formscape;documents;distributed output management;multi-channel content delivery;retrieval;archive |
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train_169 | MRP in a job shop environment using a resource constrained project scheduling | model One of the most difficult tasks in a job shop manufacturing environment is to balance schedule and capacity in an ongoing basis. MRP systems are commonly used for scheduling, although their inability to deal with capacity constraints adequately is a severe drawback. In this study, we show that material requirements planning can be done more effectively in a job shop environment using a resource constrained project scheduling model. The proposed model augments MRP models by incorporating capacity constraints and using variable lead time lengths. The efficacy of this approach is tested on MRP systems by comparing the inventory carrying costs and resource allocation of the solutions obtained by the proposed model to those obtained by using a traditional MRP model. In general, it is concluded that the proposed model provides improved schedules with considerable reductions in inventory carrying costs | mrp;project management;job shop environment;inventory carrying costs;scheduling;capacity constraints;material requirements planning;resource constrained project scheduling model;variable lead time lengths;resource allocation |
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train_1692 | Passing the image test [imaging accreditation] | Accredited imaging qualifications, hot on the heels of Microsoft, Cisco and others, are taking off in the USA. Dave Tyler looks at the CDIA+ qualification that looks likely to become the exam of choice for the DM industry | imaging qualifications;cdia+;accreditation |
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train_1693 | Healthy, wealthy and wise? [health sector document management] | NHS spending will rise from Pounds 65.4bn in 2002 to Pounds 87.2bn in 2006, and by 2008, spending will total Pounds 105.6bn. David Tyler looks at how the health sector is already beginning to exploit IT, and particularly document management, to improve service and cut costs | nhs spending;scansoft paperport;it;document management |
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train_1694 | Product development: using a 3D computer model to optimize the stability of the | Rocket TM powered wheelchair A three-dimensional (3D) lumped-parameter model of a powered wheelchair was created to aid the development of the Rocket prototype wheelchair and to help explore the effect of innovative design features on its stability. The model was developed using simulation software, specifically Working Model 3D. The accuracy of the model was determined by comparing both its static stability angles and dynamic behavior as it passed down a 4.8-cm (1.9") road curb at a heading of 45 degrees with the performance of the actual wheelchair. The model's predictions of the static stability angles in the forward, rearward, and lateral directions were within 9.3, 7.1, and 3.8% of the measured values, respectively. The average absolute error in the predicted position of the wheelchair as it moved down the curb was 2.2 cm/m (0.9" per 3'3") traveled. The accuracy was limited by the inability to model soft bodies, the inherent difficulties in modeling a statically indeterminate system, and the computing time. Nevertheless, it was found to be useful in investigating the effect of eight design alterations on the lateral stability of the wheelchair. Stability was quantified by determining the static lateral stability angles and the maximum height of a road curb over which the wheelchair could successfully drive on a diagonal heading. The model predicted that the stability was more dependent on the configuration of the suspension system than on the dimensions and weight distribution of the wheelchair. Furthermore, for the situations and design alterations studied, predicted improvements in static stability were not correlated with improvements in dynamic stability | innovative design features;weight distribution;dynamic stability improvements;predicted position;rocket tm powered wheelchair;4.8 cm;design alterations effect;suspension system configuration;soft bodies modeling;average absolute error;statically indeterminate system;product development;3d computer model;diagonal heading;computing time |
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train_1695 | Medical image computing at the Institute of Mathematics and Computer Science in | Medicine, University Hospital Hamburg-Eppendorf The author reviews the history of medical image computing at his institute, summarizes the achievements, sketches some of the difficulties encountered, and draws conclusions that might be of interest especially to people new to the field. The origin and history section provides a chronology of this work, emphasizing the milestones reached during the past three decades. In accordance with the author's group's focus on imaging, the paper is accompanied by many pictures, some of which, he thinks, are of historical value | historical value;work chronology;medical diagnostic imaging;university hospital hamburg-eppendorf;medical image computing history;institute of mathematics and computer science in medicine;difficulties encountered |
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train_1696 | Comments on "Frequency decomposition and computing of ultrasound medical images | with wavelet packets" In this paper, errors and discrepancies in the subject paper [Cincotti et al. (2002)] are highlighted. A comment, concerning the axial resolution associated to the adopted processing procedure is also reported | frequency decomposition;wavelet packets;axial resolution;medical diagnostic imaging;ultrasound medical images |
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train_1697 | Exact frequency-domain reconstruction for thermoacoustic tomography. II. | Cylindrical geometry For pt. I see ibid., vol. 21, no. 7, p. 823-8 (2002). Microwave-induced thermoacoustic tomography (TAT) in a cylindrical configuration is developed to image biological tissue. Thermoacoustic signals are acquired by scanning a flat ultrasonic transducer. Using a new expansion of a spherical wave in cylindrical coordinates, we apply the Fourier and Hankel transforms to TAT and obtain an exact frequency-domain reconstruction method. The effect of discrete spatial sampling on image quality is analyzed. An aliasing-proof reconstruction method is proposed. Numerical and experimental results are included | hankel transform;flat ultrasonic transducer;aliasing-proof reconstruction method;thermoacoustic tomography;discrete spatial sampling effect;medical diagnostic imaging;cylindrical geometry;ultrasound imaging;frequency-domain reconstruction;spherical wave expansion |
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train_1698 | Exact frequency-domain reconstruction for thermoacoustic tomography. I. Planar | geometry We report an exact and fast Fourier-domain reconstruction algorithm for thermoacoustic tomography in a planar configuration assuming thermal confinement and constant acoustic speed. The effects of the finite size of the detector and the finite length of the excitation pulse are explicitly included in the reconstruction algorithm. The algorithm is numerically and experimentally verified. We also demonstrate that the blurring caused by the finite size of the detector surface is the primary limiting factor on the resolution and that it can be compensated for by deconvolution | thermal confinement;primary limiting factor;constant acoustic speed;reconstruction algorithm;deconvolution;blurring;planar configuration;resolution limitation;thermoacoustic tomography;medical diagnostic imaging;planar geometry;exact frequency-domain reconstruction;finite detector surface size;excitation pulse |
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train_1699 | Time-domain reconstruction for thermoacoustic tomography in a spherical | geometry Reconstruction-based microwave-induced thermoacoustic tomography in a spherical configuration is presented. Thermoacoustic waves from biological tissue samples excited by microwave pulses are measured by a wide-band unfocused ultrasonic transducer, which is set on a spherical surface enclosing the sample. Sufficient data are acquired from different directions to reconstruct the microwave absorption distribution. An exact reconstruction solution is derived and approximated to a modified backprojection algorithm. Experiments demonstrate that the reconstructed images agree well with the original samples. The spatial resolution of the system reaches 0.5 mm | time-domain reconstruction;exact reconstruction solution;spherical geometry;spherical surface enclosing sample;biological tissue samples;thermoacoustic tomography;0.5 mm;modified backprojection algorithm;medical diagnostic imaging;reconstructed images;system spatial resolution;wide-band unfocused ultrasonic transducer |
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train_17 | Fault diagnosis and fault tolerant control of linear stochastic systems with | unknown inputs This paper presents an integrated robust fault detection and isolation (FDI) and fault tolerant control (FTC) scheme for a fault in actuators or sensors of linear stochastic systems subjected to unknown inputs (disturbances). As usual in this kind of works, it is assumed that single fault occurs at a time and the fault treated is of random bias type. The FDI module is constructed using banks of robust two-stage Kalman filters, which simultaneously estimate the state and the fault bias, and generate residual sets decoupled from unknown disturbances. All elements of residual sets are evaluated by using a hypothesis statistical test, and the fault is declared according to the prepared decision logic. The FTC module is activated based on the fault indicator, and additive compensation signal is computed using the fault bias estimate and combined to the nominal control law for compensating the fault's effect on the system. Simulation results for the simplified longitudinal flight control system with parameter variations, process and measurement noises demonstrate the effectiveness of the approach proposed | state estimation;fault detection;fault tolerant control;longitudinal flight control system;linear systems;two-stage kalman filters;robust control;stochastic systems;fault isolation;discrete-time system |
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train_170 | The impact of the product mix on the value of flexibility | Product-mix flexibility is one of the major types of manufacturing flexibility, referring to the ability to produce a broad range of products or variants with presumed low changeover costs. The value of such a capability is important to establish for an industrial firm in order to ensure that the flexibility provided will be at the right level and used profitably rather than in excess of market requirements and consequently costly. We use option-pricing theory to analyse the impact of various product-mix issues on the value of flexibility. The real options model we use incorporates multiple products, capacity constraints as well as set-up costs. The issues treated here include the number of products, demand variability, correlation between products, and the relative demand distribution within the product mix. Thus, we are interested in the nature of the input data to analyse its effect on the value of flexibility. We also check the impact at different capacity levels. The results suggest that the value of flexibility (i) increases with an increasing number of products, (ii) decreases with increasing volatility of product demand, (iii) decreases the more positively correlated the demand is, and (iv) reduces for marginal capacity with increasing levels of capacity. Of these, the impact of positively correlated demand seems to be a major issue. However, the joint impact of the number of products and demand correlation showed some non-intuitive results | marginal capacity;flexible manufacturing;option-pricing theory;positively correlated demand;multiple products;industrial firm;product demand volatility;manufacturing flexibility;capital budgeting;product correlation;demand variability;low changeover costs;demand correlation;product-mix flexibility;capacity constraints;real options model;relative demand distribution;set-up costs |
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train_1700 | Computation of unmeasured third-generation VCT views from measured views | We compute unmeasured cone-beam projections from projections measured by a third-generation helical volumetric computed tomography system by solving a characteristic problem for an ultrahyperbolic differential equation [John (1938)]. By working in the Fourier domain, we convert the second-order PDE into a family of first-order ordinary differential equations. A simple first-order integration is used to solve the ODES | first-order ordinary differential equations;ultrahyperbolic differential equation;range conditions;third-generation helical volumetric computed tomography system;characteristic problem solution;unmeasured third-generation vct views computation;fourier domain;measured views;medical diagnostic imaging;simple first-order integration;cone-beam projections |
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train_1701 | Estimation of 3-D left ventricular deformation from medical images using | biomechanical models The quantitative estimation of regional cardiac deformation from three-dimensional (3-D) image sequences has important clinical implications for the assessment of viability in the heart wall. We present here a generic methodology for estimating soft tissue deformation which integrates image-derived information with biomechanical models, and apply it to the problem of cardiac deformation estimation. The method is image modality independent. The images are segmented interactively and then initial correspondence is established using a shape-tracking approach. A dense motion field is then estimated using a transversely isotropic, linear-elastic model, which accounts for the muscle fiber directions in the left ventricle. The dense motion field is in turn used to calculate the deformation of the heart wall in terms of strain in cardiac specific directions. The strains obtained using this approach in open-chest dogs before and after coronary occlusion, exhibit a high correlation with strains produced in the same animals using implanted markers. Further, they show good agreement with previously published results in the literature. This proposed method provides quantitative regional 3-D estimates of heart deformation | regional cardiac deformation;biomechanical models;open-chest dogs;quantitative estimation;interactively segmented images;cardiac specific directions;left ventricular motion estimation;nonrigid motion estimation;transversely isotropic linear-elastic model;muscle fiber directions;3-d left ventricular deformation estimation;medical diagnostic imaging;magnetic resonance imaging;generic methodology;3-d image sequences |
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train_1702 | Reconstruction of time-varying 3-D left-ventricular shape from multiview X-ray | cineangiocardiograms This paper reports on the clinical application of a system for recovering the time-varying three-dimensional (3-D) left-ventricular (LV) shape from multiview X-ray cineangiocardiograms. Considering that X-ray cineangiocardiography is still commonly employed in clinical cardiology and computational costs for 3-D recovery and visualization are rapidly decreasing, it is meaningful to develop a clinically applicable system for 3-D LV shape recovery from X-ray cineangiocardiograms. The system is based on a previously reported closed-surface method of shape recovery from two-dimensional occluding contours with multiple views. To apply the method to "real" LV cineangiocardiograms, user-interactive systems were implemented for preprocessing, including detection of LV contours, calibration of the imaging geometry, and setting of the LV model coordinate system. The results for three real LV angiographic image sequences are presented, two with fixed multiple views (using supplementary angiography) and one with rotating views. 3-D reconstructions utilizing different numbers of views were compared and evaluated in terms of contours manually traced by an experienced radiologist. The performance of the preprocesses was also evaluated, and the effects of variations in user-specified parameters on the final 3-D reconstruction results were shown to be sufficiently small. These experimental results demonstrate the potential usefulness of combining multiple views for 3-D recovery from "real" LV cineangiocardiograms | b-spline;multiview x-ray cineangiocardiograms;computational costs;clinical cardiology;time-varying 3-d left-ventricular shape reconstruction;fixed multiple views;angiographic image sequences;user-interactive systems;two-dimensional occluding contours;medical diagnostic imaging;user-specified parameters variations;experienced radiologist;arterial septal defect |
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train_1703 | Statistical analysis of nonlinearly reconstructed near-infrared tomographic | images. II. Experimental interpretation For pt. I see ibid., vol. 21, no. 7, p. 755-63 (2002). Image error analysis of a diffuse near-infrared tomography (NIR) system has been carried out on simulated data using a statistical approach described in pt. I of this paper (Pogue et al., 2002). The methodology is used here with experimental data acquired on phantoms with a prototype imaging system intended for characterizing breast tissue. Results show that imaging performance is not limited by random measurement error, but rather by calibration issues. The image error over the entire field of view is generally not minimized when an accurate homogeneous estimate of the phantom properties is available; however, local image error over a target region of interest (ROI) is reduced. The image reconstruction process which includes a Levenberg-Marquardt style regularization provides good minimization of the objective function, yet its reduction is not always correlated with an overall image error decrease. Minimization of the bias in an ROI which contains localized changes in the optical properties can be achieved through five to nine iterations of the algorithm. Precalibration of the algorithm through statistical evaluation of phantom studies may provide a better measure of the image accuracy than that implied by minimization of the standard objective function | nonlinearly reconstructed near-infrared tomographic images;random measurement error;target region of interest;accurate homogeneous estimate;image error;bias minimization;phantom properties;hemoglobin;medical diagnostic imaging;objective function minimization;algorithm iterations;algorithm precalibration;levenberg-marquardt style regularization |
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train_1704 | Statistical analysis of nonlinearly reconstructed near-infrared tomographic | images. I. Theory and simulations Near-infrared (NIR) diffuse tomography is an emerging method for imaging the interior of tissues to quantify concentrations of hemoglobin and exogenous chromophores noninvasively in vivo. It often exploits an optical diffusion model-based image reconstruction algorithm to estimate spatial property values from measurements of the light flux at the surface of the tissue. In this study, mean-squared error (MSE) over the image is used to evaluate methods for regularizing the ill-posed inverse image reconstruction problem in NIR tomography. Estimates of image bias and image standard deviation were calculated based upon 100 repeated reconstructions of a test image with randomly distributed noise added to the light flux measurements. It was observed that the bias error dominates at high regularization parameter values while variance dominates as the algorithm is allowed to approach the optimal solution. This optimum does not necessarily correspond to the minimum projection error solution, but typically requires further iteration with a decreasing regularization parameter to reach the lowest image error. Increasing measurement noise causes a need to constrain the minimum regularization parameter to higher values in order to achieve a minimum in the overall image MSE | ill-posed inverse image reconstruction problem regularization;test image;light flux;spatial property values estimation;mean-squared error;lowest image error;decreasing regularization parameter;minimum regularization parameter constraint;photon migration;o/sub 2/;randomly distributed noise;optimal solution;medical diagnostic imaging;hemoglobin;bias error;oxygen saturation;optical diffusion model-based image reconstruction algorithm |
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train_1705 | The use of visual search for knowledge gathering in image decision support | This paper presents a new method of knowledge gathering for decision support in image understanding based on information extracted from the dynamics of saccadic eye movements. The framework involves the construction of a generic image feature extraction library, from which the feature extractors that are most relevant to the visual assessment by domain experts are determined automatically through factor analysis. The dynamics of the visual search are analyzed by using the Markov model for providing training information to novices on how and where to look for image features. The validity of the framework has been evaluated in a clinical scenario whereby the pulmonary vascular distribution on Computed Tomography images was assessed by experienced radiologists as a potential indicator of heart failure. The performance of the system has been demonstrated by training four novices to follow the visual assessment behavior of two experienced observers. In all cases, the accuracy of the students improved from near random decision making (33%) to accuracies ranging from 50% to 68% | visual assessment behavior;student accuracy;experienced observers;heart failure indicator;pulmonary vascular distribution;training information;domain experts;medical diagnostic imaging;markov model;saccadic eye movements dynamics;experienced radiologists;image features;near random decision making |
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train_1706 | Quantitative analysis of reconstructed 3-D coronary arterial tree and | intracoronary devices Traditional quantitative coronary angiography is performed on two-dimensional (2-D) projection views. These views are chosen by the angiographer to minimize vessel overlap and foreshortening. With 2-D projection views that are acquired in this nonstandardized fashion, however, there is no way to know or estimate how much error occurs in the QCA process. Furthermore, coronary arteries possess a curvilinear shape and undergo a cyclical deformation due to their attachment to the myocardium. Therefore, it is necessary to obtain three-dimensional (3-D) information to best describe and quantify the dynamic curvilinear nature of the human coronary artery. Using a patient-specific 3-D coronary reconstruction algorithm and routine angiographic images, a new technique is proposed to describe: (1) the curvilinear nature of 3-D coronary arteries and intracoronary devices; (2) the magnitude of the arterial deformation caused by intracoronary devices and due to heart motion; and (3) optimal view(s) with respect to the desired "pathway" for delivering intracoronary devices | patient-specific 3-d coronary reconstruction algorithm;routine angiographic images;myocardium;intracoronary devices delivery pathway;cyclical deformation;medical diagnostic imaging;human coronary artery;arterial deformation magnitude;dynamic curvilinear nature quantification |
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train_1707 | Tactical airborne reconnaissance goes dual-band and beyond | Multispectral imaging technologies are satisfying the need for a "persistent" look at the battlefield. We highlight the need to persistently monitor a battlefield to determine exactly who and what is there. For example, infrared imaging can be used to expose the fuel status of an aircraft on the runway. A daytime, visible-spectrum image of the same aircraft would offer information about external details, such as the plane's markings and paint scheme. A dual-band camera enables precision image registration by fusion and frequently yields more information than is possible by evaluating the images separately | aircraft;daytime visible-spectrum image;sensor fusion;dual-band camera;infrared imaging;fuel status;tactical airborne reconnaissance;multispectral imaging technologies;battlefield;precision image registration |
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train_1708 | A study of hospitality and tourism information technology education and | industrial applications The purpose of this study was to examine the subject relevance of information technology (IT) in hospitality and tourism management programs with skills deployed in the workplace. This study aimed at investigating graduates' transition from education to employment, and to determine how well they appear to be equipped to meet the needs of the hospitality and tourism industry. One hundred and seventeen graduates responded to a mail survey. These graduates rated the importance of IT skills in the workplace, the level of IT teaching in hotel and tourism management programs, and the self-competence level in IT. This study concluded that a gap exists between the IT skills required at work and those acquired at university | employment;university;tourism industry;it skills;mail survey;hospitality and tourism management programs;graduates;it teaching;hospitality industry;education |
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train_1709 | Development of computer-mediated teaching resources for tourism distance | education: the University of Otago model This article presents a qualitative account of the development of computer-mediated tourism distance learning resources. A distance learning model was developed at the Centre for Tourism, University of Otago (New Zealand) in 1998-1999. The article reviews the development of this Internet-based learning resource explaining the design and development of programme links (providing study information for students) and paper links (course material and learning features). The design of course material is reviewed with emphasis given to consistency of presentation between papers. The template for course material is described and illustrated and the article concludes with an overview of important design considerations | internet-based learning resource;computer-mediated tourism distance learning resources;paper links;university of otago;programme links |
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train_171 | Education, training and development policies and practices in medium-sized | companies in the UK: do they really influence firm performance? This paper sets out to examine the relationship between training and firm performance in middle-sized UK companies. It recognises that there is evidence that "high performance work practices" appear to be associated with better performance in large US companies, but argues that this relationship is less likely to be present in middle-sized companies. The paper's key contribution is to justify the wider concept of education, training and development (ETD) as applicable to such companies. It then finds that clusters of some ETD variables do appear to be associated with better middle-sized company performance | training;etd variable clusters;firm performance;high performance work practices;human resources;medium-sized uk companies;education;development policies |
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train_1710 | VONNA(HBP): a multimedia learning package on hotel budget planning | In this paper, a new learning package, VONNA(HBP), which provides an interactive and online environment for novices to study and practice hotel budget planning, is introduced. Its design philosophy will be discussed thoughtfully with special focus on how to make use of the multimedia and Internet. According to literatures, learning packages are faced to be more effective in delivering teaching material. Researchers indicate that students using a self-paced learning package score higher than in a traditional classroom setting. Moreover, the learning package provides different scenarios for students to explore themselves in a practical environment and is more cost effective and systematic than lectures. Currently, most learning packages in hotel education are not implemented using multimedia with Internet access. Our paper describes a new learning package that fills the gaps. VONNA(HBP) requires participants to investigate operational budgets on various areas such as sales levels, payroll, inventory level, promotion strategies, and facilities planning, etc. Eventually, the students/novices are required to practice their skills in a comprehensive case about a hypothetical hotel. They need to solve managerial problems by a combination of budgetary planning on human resources, staff training programmes, facilities' maintenance and replacement, or promotion schemes. Analytical tools are available for students/novices to judge an appropriate decision in handling constrained resources | self-paced learning package;sales;internet;multimedia learning package;hotel education;hotel budget planning;facility maintenance;interactive online environment;vonna(hbp);facility replacement;human resources;constrained resource handling;teaching material delivery;managerial problems;promotion strategies;staff training programmes;payroll;facilities planning;inventory |
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train_1711 | Developing a CD-ROM as a teaching and learning tool in food and beverage | management: a case study in hospitality education Food and beverage management is the traditional core of hospitality education but, in its laboratory manifestation, has come under increasing pressure in recent years. It is an area that, arguably, presents the greatest challenges in adaptation to contemporary learning technologies but, at the same time, stands to benefit most from the potential of the Web. This paper addresses the design and development of a CD-ROM learning resource for food and beverage. It is a learning resource which is designed to integrate with rather than to replace existing conventional classroom and laboratory learning methods and, thus, compensate for the decline in the resource base faced in food and beverage education in recent years. The paper includes illustrative material drawn from the CD-ROM which demonstrates its use in teaching and learning | food and beverage management;learning tool;cd-rom;teaching tool;hospitality education |
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train_1712 | Eliminating counterevidence with applications to accountable certificate | management This paper presents a method to increase the accountability of certificate management by making it intractable for the certification authority (CA) to create contradictory statements about the validity of a certificate. The core of the method is a new primitive, undeniable attester, that allows someone to commit to some set S of bitstrings by publishing a short digest of S and to give attestations for any x that it is or is not a member of S. Such an attestation can be verified by obtaining in an authenticated way the published digest and applying a verification algorithm to the triple of the bitstring, the attestation and the digest. The most important feature of this primitive is the intractability of creating two contradictory proofs for the same candidate element x and digest. We give an efficient construction for undeniable attesters based on authenticated search trees. We show that the construction also applies to sets of more structured elements. We also show that undeniable attesters exist iff collision-resistant hash functions exist | long-term authenticity;accountable certificate management;undeniable attester primitive;accountability;attestations;bitstring;counterevidence elimination;collision-resistant hash functions;contradictory proofs;time-stamping;public-key infrastructure;non repudiation;structured elements;verification algorithm;certification authority;authenticated search trees;published digest |
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train_1713 | A uniform framework for regulating service access and information release on | the Web The widespread use of Internet-based services is increasing the amount of information (such as user profiles) that clients are required to disclose. This information demand is necessary for regulating access to services, and functionally convenient (e.g., to support service customization), but it has raised privacy-related concerns which, if not addressed, may affect the users disposition to use network services. At the same time, servers need to regulate service access without disclosing entirely the details of their access control policy. There is therefore a pressing need for privacy-aware techniques to regulate access to services open to the network. We propose an approach for regulating service access and information disclosure on the Web. The approach consists of a uniform formal framework to formulate - and reason about - both service access and information disclosure constraints. It also provides a means for parties to communicate their requirements while ensuring that no private information be disclosed and that the communicated requirements are correct with respect to the constraints | internet;network services;user profiles;uniform formal framework;privacy-aware techniques;reasoning;information release;information disclosure;client server systems;service access regulation;information demand;access control policy;www |
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train_1714 | Hordes: a multicast based protocol for anonymity | With widespread acceptance of the Internet as a public medium for communication and information retrieval, there has been rising concern that the personal privacy of users can be eroded by cooperating network entities. A technical solution to maintaining privacy is to provide anonymity. We present a protocol for initiator anonymity called Hordes, which uses forwarding mechanisms similar to those used in previous protocols for sending data, but is the first protocol to make use of multicast routing to anonymously receive data. We show this results in shorter transmission latencies and requires less work of the protocol participants, in terms of the messages processed. We also present a comparison of the security and anonymity of Hordes with previous protocols, using the first quantitative definition of anonymity and unlinkability. Our analysis shows that Hordes provides anonymity in a degree similar to that of Crowds and Onion Routing, but also that Hordes has numerous performance advantages | initiator anonymity;protocol;multicast routing;transmission latencies;onion routing;performance;internet;crowds;unlinkability;personal privacy;hordes;cooperating network entities;forwarding mechanisms |
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train_1715 | Information-processing and computing systems at thermal power stations in China | The development and commissioning of information-processing and computing systems (IPCSs) at four power units, each of 500 MW capacity at the thermal power stations Tszisyan' and Imin' in China, are considered. The functional structure and the characteristics of the functions of the IPCSs are presented as is information on the technology of development and experience in adjustments. Ways of using the experience gained in creating a comprehensive functional firmware system are shown | 500 mw;commissioning;thermal power stations;functional structure;firmware system;development;information-processing systems;china;functions characteristics;computing systems |
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train_1716 | The vibration reliability of poppet and contoured actuator valves | The problem of selecting the shape of the actuator valve (the final control valve) itself is discussed; the solution to this problem will permit appreciable dynamic loads to be eliminated from the moving elements of the steam distribution system of steam turbines under all operating conditions | actuator valve shape selection;steam distribution system;steam turbines;vibration reliability;contoured actuator valves;poppet actuator valves;dynamic loads elimination;moving elements |
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train_1717 | Responding to market trends with predictive segmentation [health care] | Technology and technological advances have always been a part of healthcare, but often it's advances in treatment machinery and materials that get the attention. However, technology gains also occur behind the scenes in operations. One of the less glamorous but powerful technological advances available today is predictive segmentation, a phrase that means "a new way to assess and view individuals in the market based on their health status and health needs." Sophisticated databases, data mining, neural networks and statistical capabilities have enabled the development of predictive segmentation techniques. These predictive models for healthcare can identify who is likely to need certain services and who is likely to become ill. They are a significant departure from various geographical and attitudinal segmentation methods that healthcare strategists have used in the past to gain a better understanding of their customers | data mining;market trends;predictive segmentation;neural networks;healthcare |
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train_1719 | The UPS as network management tool | Uninterrupted power supplies (UPS), or battery backup systems, once provided a relatively limited, although important, function-continual battery support to connected equipment in the event of a power failure. However, yesterday's "battery in a box" has evolved into a sophisticated network power management tool that can monitor and actively correct many of the problems that might plague a healthy network. This new breed of UPS system provides such features as automatic voltage regulation, generous runtimes and unattended system shutdown, and now also monitors and automatically restarts critical services and operating systems if they lock up or otherwise fail | network power management;automatic voltage regulation;uninterrupted power supplies;unattended system shutdown |
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train_172 | A VMEbus interface for multi-detector trigger and control system | MUSE (MUltiplicity SElector) is the trigger and control system of CHIMERA, a 4 pi charged particle detector. Initialization of MUSE can be performed via VMEbus. This paper describes the design of VMEbus interface and functional module in MUSE, and briefly discusses an application of MUSE | chimera;trigger system;muse;control system;vmebus interface |
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train_1721 | Dueling platforms [healthcare network servers] | Many large hospitals and healthcare systems have grown accustomed to the reliability of mainframe architecture, although tighter operating budgets, coupled with advances in client/server technology, have led to more office and clinical applications being moved off mainframes. But Evanston Northwestern Healthcare wasn't ready to get rid of its IBM OS 390 mainframe just yet. While a number of new clinical applications are being installed on two brand new IBM servers, Evanston Northwestern Healthcare will retain its favored hospital billing system and let it reside on the organization's mainframe, as it has since 1982 | network servers;evanston northwestern healthcare;leapfrog group;ibm os 390 mainframe;computerized physician order entry system |
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train_1723 | Positive productivity, better billing [health care] | Workflow software provides the right communication solution for hospital specialists, and delivers an unexpected financial boost too | san francisco general hospital;workflow software;health care;provation md |
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train_1724 | A winning combination [wireless health care] | Three years ago, the Institute of Medicine (IOM) reported that medical errors result in at least 44,000 deaths each year-more than deaths from highway accidents, breast cancer or AIDS. That report, and others which placed serious errors as high as 98,000 annually, served as a wake-up call for healthcare providers such as the CareGroup Healthcare System Inc., a Boston-area healthcare network that is the second largest integrated delivery system in the northeastern United States. With annual revenues of $1.2B, CareGroup provides primary care and specialty services to more than 1,000,000 patients. CareGroup combined wireless technology with the Web to create a provider order entry (POE) system designed to reduce the frequency of costly medical mistakes. The POE infrastructure includes InterSystems Corporation's CACHE database, Dell Computer C600 laptops and Cisco Systems' Aironet 350 wireless networks | cisco systems aironet 350 wireless networks;dell computer c600 laptops;healthcare network;intersystems corporation cache database;wireless;caregroup healthcare system;medical errors;provider order entry |
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train_1725 | Cutting the cord [wireless health care] | More and more healthcare executives are electing to cut the cord to their existing computer systems by implementing mobile technology. The allure of information anywhere, anytime is intoxicating, demonstrated by the cell phones and personal digital assistants (PDAs) that adorn today's professionals. The utility and convenience of these devices is undeniable. But what is the best strategy for implementing a mobile solution within a healthcare enterprise, be it large or small-and under what circumstances? What types of healthcare workers benefit most from mobile technology? And how state-of-the-art is security for wireless applications and devices? These are the questions that healthcare executives are asking-and should be asking-as they evaluate mobile solutions | mobile computing;security;wireless computing;healthcare |
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train_1726 | Two-layer model for the formation of states of the hidden Markov chains | Procedures for the formation of states of the hidden Markov models are described. Formant amplitudes and frequencies are used as state features. The training strategy is presented that allows one to calculate the parameters of conditional probabilities of the generation of a given formant set by a given hidden state with the help of the maximum likelihood method | state features;conditional probabilities;hidden state;hidden markov models;formant amplitudes;formant frequencies;maximum likelihood method |
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train_1727 | Linguistic knowledge and new technologies | Modern language studies are characterized by a variety of forms, ways, and methods of their development. In this connection, it is necessary to specify the problem of the development of their internal differentiation and classification, which lead to the formation of specific areas knowledge. An example of such an area is speechology-a field of science belonging to fundamental, theoretical, and applied linguistics | theoretical linguistics;speechology;applied linguistics;internal differentiation;fundamental linguistics;internal classification;modern language studies;linguistic knowledge |
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train_1728 | A characterization of generalized Pareto distributions by progressive censoring | schemes and goodness-of-fit tests In this paper we generalize a characterization property of generalized Pareto distributions, which is known for ordinary order statistics, to arbitrary schemes of progressive type-II censored order statistics. Various goodness-of-fit tests for generalized Pareto distributions based on progressively censored data statistics are discussed | progressive type-ii censored order statistics;progressive censoring schemes;generalized pareto distributions;goodness-of-fit tests;ordinary order statistics |
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train_1729 | Maintaining e-commerce | E-commerce over the Web has created a relatively new type of information system. So it is hardly surprising that little attention has been given to the maintenance of such systems-and even less to attempting to develop them with future maintenance in mind. But there are various ways e-commerce systems can be developed to reduce future maintenance | web systems;e-commerce systems maintenance |
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train_173 | Stock market trading rule discovery using technical charting heuristics | In this case study in knowledge engineering and data mining, we implement a recognizer for two variations of the 'bull flag' technical charting heuristic and use this recognizer to discover trading rules on the NYSE Composite Index. Out-of-sample results indicate that these rules are effective | out-of-sample results;case study;data mining;technical charting heuristics;financial expert system;rule discovery;nyse composite index;stock market trading;knowledge engineering |
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train_1730 | Meeting of minds | Technical specialists need to think about their role in IT projects and how they communicate with end-users and other participants to ensure they contribute fully as team members. It is especially important to communicate and document trade-offs that may have to be made, including the rationale behind them, so that if requirements change, the impact and decisions can be readily communicated to the stakeholders | communication;technical specialists;end-users;it projects |
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train_1731 | Hit the road, Jack | Going freelance offers the potential of higher earnings, variety and independence - but also removes the benefits of permanent employment and can mean long distance travel and periods out of work. The author looks at the benefits and drawbacks - and how to get started as an IT contractor | it contractor;freelance working |
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train_1732 | Community spirit | IT companies that contribute volunteers, resources or funding to charities and local groups not only make a real difference to their communities but also add value to their businesses. So says a new coalition of IT industry bodies formed to raise awareness of the options for community involvement, promote the business case, and publicise examples of best practice. The BCS, Intellect (formed from the merger of the Computing Services and Software Association and the Federation of the Electronics Industry) and the Worshipful Company of Information Technologists plan to run advisory seminars and provide guidelines on how companies of all sizes can transform their local communities using their specialist IT skills and resources while reaping business benefits | volunteer staff;resource contribution;staff development;it companies;best practice;community projects;business benefits;charity projects |
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train_1733 | Computing grid unlocks research | Under the UK government's spending review in 2000 the Office of Science and Technology was allocated Pounds 98m to establish a three year e-science research and development programme. The programme has a bold vision: to change the dynamic of the way science is undertaken. The term 'e-science' was introduced by John Taylor, director general of research councils in the Office of Science and Technology. He saw many areas of science becoming increasingly reliant on new ways of collaborative, multidisciplinary, interorganisation working. E-science is intended to capture these new modes of working. There are two major components to the programme: the science, and the infrastructure to support that science. The infrastructure is generally referred to as the Grid. The choice of name resonates with the idea of a future in which computing resources and storage, as well as expensive scientific facilities and software, can be accessed on demand, like electricity. Open source prototypes of the middleware are available and under development as part of the e-science programme and other international efforts | computing resources;software;open source prototypes;grid computing;uk programme;middleware;e-science;collaboration;scientific research |
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train_1734 | Going electronic [auditing] | A study group examines the issues auditors face in gathering electronic information as evidence and its impact on the audit | auditing;electronic information;assurance standards;audit evidence |
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train_1735 | Mid-market accounting systems | Welcome to our fourth annual survey of accounting systems and enterprise resource planning (ERP) systems. Last September, we concentrated on financial and distribution systems for medium-sized businesses (mid market) and included 22 products in our charts. This year, we extended the products to include manufacturing and added 34 products to the list | mid-market accounting systems;enterprise resource planning;survey;manufacturing |
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train_1736 | Wired right [accounting] | From business intelligence to wireless networking to service providers, here is what you need to know to keep up to speed with a changing landscape | service providers;wireless networking;accounting;business intelligence |
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train_1737 | The road to recovery [disaster planning] | September 11 stripped us of our innocence, forcing corporations to recognize that disaster planning is a business necessity | disaster planning;recovery;risk management |
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train_1738 | Nurture the geek in you [accounting on the Internet] | When chartered accountants focus on IT, it's not simply because we think technology is neat. We keep on top of tech trends and issues because it helps us do our jobs well. We need to know how to best manage and implement the wealth of technology systems within out client base or employer, as well as to determine on an ongoing basis how evolving technologies might affect business strategies, threats and opportunities. One way to stay current with technology is by monitoring the online drumbeat. Imagine the Internet as an endless conversation of millions of chattering voices, each focusing on a multitude of topics and issues. It's not surprising that a great deal of the information relates to technology itself, and if you learn how to tune in to the drumbeat, you can keep yourself informed | securityfocus;techdirt;chartered accountants;internet;information technology;dan gillmor's wournal;techweb;slashdot;risks;the register;daypop top 40 |
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train_1739 | Application of normal possibility decision rule to silence | The paper presents the way of combining two decision problems concerning a single (or a common) dimension, so that an effective fuzzy decision rule can be obtained. Normality of the possibility distribution is assumed, leading to possibility of fusing the respective functions related to the two decision problems and their characteristics (decisions, states of nature, utility functions, etc.). The approach proposed can be applied in cases when the statement of the problem requires making of more refined distinctions rather than considering simply a bi-criterion or bi-utility two-decision problem | silence;conflicting objectives;conflicting utilities;normal possibility decision rule;warm heart;decision problems;two-dimensional fuzzy events;cool head |
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train_174 | The BIOGENES system for knowledge-based bioprocess control | The application of knowledge-based control systems in the area of biotechnological processes has become increasingly popular over the past decade. This paper outlines the structure of the advanced knowledge-based part of the BIOGENES Copyright control system for the control of bioprocesses such as the fed-batch Saccharomyces cerevisiae cultivation. First, a brief overview of all the tasks implemented in the knowledge-based level including process data classification, qualitative process state identification and supervisory process control is given. The procedures performing the on-line identification of metabolic states and supervisory process control (setpoint calculation and control strategy selection) are described in more detail. Finally, the performance of the system is discussed using results obtained from a number of experimental cultivation runs in a laboratory unit | qualitative process state identification;biotechnological processes;online identification;fed-batch saccharomyces cerevisiae cultivation;metabolic states;process data classification;biogenes system;supervisory process control;experiment;knowledge-based bioprocess control |
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train_1740 | Verification of ideological classifications-a statistical approach | The paper presents a statistical method of verifying ideological classifications of votes. Parliamentary votes, preclassified by an expert (on a chosen subset), are verified at an assumed significance level by seeking the most likely match with the actual vote results. Classifications that do not meet the requirements defined are rejected. The results obtained can be applied in the ideological dimensioning algorithms, enabling ideological identification of dimensions obtained | ideological dimensioning algorithms;statistical approach;parliamentary votes;significance level;bootstrap;ideological space;ideological classifications |
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train_1741 | The top cycle and uncovered solutions for weak tournaments | We study axiomatic properties of the top cycle and uncovered solutions for weak tournaments. Subsequently, we establish its connection with the rational choice theory | rational choice theory;weak tournaments;uncovered solutions;axiomatic properties;top cycle |
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train_1742 | A sufficient condition for optimality in nondifferentiable invex programming | A sufficient optimality condition is established for a nonlinear programming problem without differentiability assumption on the data wherein Clarke's (1975) generalized gradient is used to define invexity | locally lipschitz function;generalized gradient;invexity;semiconvex function;sufficient optimality condition;nondifferentiable invex programming;nonlinear programming problem |
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train_1743 | Adaptive stabilization of undamped flexible structures | In the paper non-identifier-based adaptive stabilization of undamped flexible structures is considered in the case of collocated input and output operators. The systems have poles and zeros on the imaginary axis. In the case where velocity feedback is available, the adaptive stabilizer is constructed by an adaptive PD-controller (proportional plus derivative controller). In the case where only position feedback is available, the adaptive stabilizer is constructed by an adaptive P-controller for the augmented system which consists of the controlled system and a parallel compensator. Numerical examples are given to illustrate the effectiveness of the proposed controllers | position feedback;poles and zeros;adaptive stabilization;velocity feedback;adaptive p-controller;proportional plus derivative controller;parallel compensator;undamped flexible structures;adaptive pd-controller;augmented system;imaginary axis |
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train_1744 | Convergence of Toland's critical points for sequences of DC functions and | application to the resolution of semilinear elliptic problems We prove that if a sequence (f/sub n/)/sub n/ of DC functions (difference of two convex functions) converges to a DC function f in some appropriate way and if u/sub n/ is a critical point of f/sub n/, in the sense described by Toland (1978, 1979), and is such that (u/sub n/)/sub n/ converges to u, then u is a critical point of f, still in Toland's sense. We also build a new algorithm which searches for this critical point u and then apply it in order to compute the solution of a semilinear elliptic equation | semilinear elliptic problems;convex function difference;semilinear elliptic equation;dc function sequences;critical point convergence |
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train_1745 | Approximate relaxed descent method for optimal control problems | We consider an optimal control problem for systems governed by ordinary differential equations with control constraints. Since no convexity assumptions are made on the data, the problem is reformulated in relaxed form. The relaxed state equation is discretized by the implicit trapezoidal scheme and the relaxed controls are approximated by piecewise constant relaxed controls. We then propose a combined descent and discretization method that generates sequences of discrete relaxed controls and progressively refines the discretization. Since here the adjoint of the discrete state equation is not defined, we use, at each iteration, an approximate derivative of the cost functional defined by discretizing the continuous adjoint equation and the integral involved by appropriate trapezoidal schemes. It is proved that accumulation points of sequences constructed by this method satisfy the strong relaxed necessary conditions for optimality for the continuous problem. Finally, the computed relaxed controls can be easily approximated by piecewise constant classical controls | trapezoidal schemes;discretization refinement;relaxed state equation discretization;approximate relaxed descent method;cost functional approximate derivative;optimal control problems;ordinary differential equations;relaxed control approximation;implicit trapezoidal scheme;discrete relaxed control sequences;piecewise constant relaxed controls;discrete state equation |
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train_1746 | The exact solution of coupled thermoelectroelastic behavior of piezoelectric | laminates Exact solutions for static analysis of thermoelectroelastic laminated plates are presented. In this analysis, a new concise procedure for the analytical solution of composite laminated plates with piezoelectric layers is developed. A simple eigenvalue formula in real number form is directly developed from the basic coupled piezoelectric differential equations and the difficulty of treating imaginary eigenvalues is avoided. The solution is defined in the trigonometric series and can be applied to thin and thick plates. Numerical studies are conducted on a five-layer piezoelectric plate and the complexity of stresses and deformations under combined loading is illustrated. The results could be used as a benchmark for assessing any numerical solution by approximate approaches such as the finite element method while also providing useful physical insight into the behavior of piezoelectric plates in a thermal environment | analytical solution;coupled thermoelectroelastic behavior;stresses;five-layer piezoelectric plate;thermal environment;coupled piezoelectric differential equations;eigenvalue formula;thick plates;piezoelectric laminates;finite element method;piezoelectric layers;exact solution;deformations;thin plates;numerical study;composite laminated plates;real number form;trigonometric series;combined loading;thermoelectroelastic laminated plates |
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train_1747 | On a general constitutive description for the inelastic and failure behavior of | fibrous laminates. II. Laminate theory and applications For pt. I see ibid., pp. 1159-76. The two papers report systematically a constitutive description for the inelastic and strength behavior of laminated composites reinforced with various fiber preforms. The constitutive relationship is established micromechanically, through layer-by-layer analysis. Namely, only the properties of the constituent fiber and matrix materials of the composites are required as input data. In the previous part lamina theory was presented. Three fundamental quantities of the laminae, i.e. the internal stresses generated in the constituent fiber and matrix materials and the instantaneous compliance matrix, with different fiber preform (including woven, braided, and knitted fabric) reinforcements were explicitly obtained by virtue of the bridging micromechanics model. In this paper, the laminate stress analysis is shown. The purpose of this analysis is to determine the load shared by each lamina in the laminate, so that the lamina theory can be applied. Incorporation of the constitutive equations into an FEM software package is illustrated. A number of application examples are given to demonstrate the efficiency of the constitutive theory. The predictions made include: failure envelopes of multidirectional laminates subjected to biaxial in-plane loads, thermomechanical cycling stress-strain curves of a titanium metal matrix composite laminate, S-N curves of multilayer knitted fabric reinforced laminates under tensile fatigue, and bending load-deflection plots and ultimate bending strengths of laminated braided fabric reinforced beams subjected to lateral loads | s-n curves;multilayer knitted fabric reinforced laminates;thermomechanical cycling stress-strain curves;inelastic behavior;matrix materials;fibrous laminates;layer-by-layer analysis;strength behavior;composites;laminate theory;load;stress analysis;multidirectional laminates;internal stresses;fem software package;micromechanics;failure behavior;ultimate bending strengths;bending load deflection plots;titanium metal matrix composite laminate;fiber preforms;laminated braided fabric reinforced beams;instantaneous compliance matrix;tensile fatigue;lateral loads;general constitutive description;failure envelopes;biaxial in-plane loads |
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train_1748 | On a general constitutive description for the inelastic and failure behavior of | fibrous laminates. I. Lamina theory It is well known that a structural design with isotropic materials can only be accomplished based on a stress failure criterion. This is, however, generally not true with laminated composites. Only when the laminate is subjected to an in-plane load, can the ultimate failure of the laminate correspond to its last-ply failure, and hence a stress failure criterion may be sufficient to detect the maximum load that can be sustained by the laminate. Even in such a case, the load shared by each lamina in the laminate cannot be correctly determined if the lamina instantaneous stiffness matrix is inaccurately provided, since the lamina is always statically indeterminate in the laminate. If, however, the laminate is subjected to a lateral load, its ultimate failure occurs before last-ply failure and use of the stress failure criterion is no longer sufficient; an additional critical deflection or curvature condition must also be employed. This necessitates development of an efficient constitutive relationship for laminated composites in order that the laminate strains/deflections up to ultimate failure can be accurately calculated. A general constitutive description for the thermomechanical response of a fibrous laminate up to ultimate failure with applications to various fibrous laminates is presented in the two papers. The constitutive relationship is obtained by combining classical lamination theory with a recently developed bridging micromechanics model, through a layer-by-layer analysis. This paper focuses on lamina analysis | micromechanics model;stress failure criterion;laminate deflections;critical deflection condition;inelastic behavior;thermomechanical response;woven fabric composites;lamina theory;fibrous laminates;layer-by-layer analysis;last-ply failure;isotropic materials;multidirectional tape laminae;composites;braided fabric composites;laminate strains;failure behavior;elastoplasticity;in-plane load;structural design;lateral load;critical curvature condition;elastic-viscoplasticity;knitted fabric reinforced composites;instantaneous stiffness matrix;general constitutive description |
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