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S1364682620300213 | A cursory or even detailed inspection of literature shows that while the annual cycle of precipitation and temperature in Zambia are well understood there is a general lack of documentation on long term trends and periodicities over the country . In this study we extensively examined the temporal and spatial changes in precipitation and temperature over Zambia for the period 19502016 . We used the modified MannKendall test with the aim of eliminating the effect of autocorrelation on precipitation and temperature trends based on Global Precipitation Climatology Centre and National Centre for Environmental Prediction National Centre for Atmospheric Research products . Overall significant decrease in precipitation was evident . We further observed that on average precipitation has been decreasing by 1.1mm yr | Precipitation has been decreasing by 1.1mm yr. across Zambia. An abrupt change in the trend of precipitation was reported in 1980 1981 significant at 5 significance level. Temperature has been increasing at a rate of 0.01C yr. No sudden changes have been observed in temperature over the country. |
S1364682620300237 | The fourth stage of the Polar Satellite Launch Vehicle of the C 38 mission was used for the first time as an orbiting platform to carry out measurements of atmospheric parameters on June 23 2017 . The measurements were made in two phases . i During the initial launch phase wherein the launch vehicle traversed from the launch pad to an altitude of 500km . ii During the 10 orbits at an altitude of 350km . The Ionization Density and Electric field Analyzer | The IDEA payload is flown on the unique PS4 orbiting platform of PSLV C38 to obtain ionospheric measurements. First of their kind in situ observations of top side plasma density structure being modulated by rocket exhaust cloud. |
S1364682620300249 | Energetic particles precipitation which transmits energy from the magnetosphere to the ionosphere represents an important coupling process between two systems . In this study we investigate the spatial distribution and temporal evolution of medium energy energetic particle precipitation with NOAA POES observations . We found the following results During storm time both energetic electron and proton precipitations exhibit dawn dusk asymmetry in the equatorial plane possibly caused by plasma waves that are excited and then interact with energetic electrons and protons at different local times . The energetic proton precipitation appears to contain greater energy flux than electrons in storm time which is contrary to the low energy particle precipitation where the electrons carry the dominant precipitation energy . The depth of the earthward inner boundary of precipitation in statistics is linearly correlated with geomagnetic activity levels represented by the SYM H index . | Medium energy tens to hundreds of keV energetic precipitation of electrons and protons both exhibits global asymmetry. Energetic proton precipitation contains more energy flux than electrons unlike the scenario in low energy precipitation. The Earthward extension of precipitation linearly correlates with the storm intensity measured by SYM H index. |
S1364682620300250 | The Himalayas are often considered pristine environments however they can be influenced by transported aerosols emitted from urbanized and industrialized areas . In the present study atmospheric PM | PM concentrations are above the permissible limit stipulated by the CPCB and WHO. Particulate pollution from IGP region influences the air quality at Dehradun. Soil dust particles have a greater contribution during the summer season. Inhalation of PM at Dehradun can lead to human health risk. |
S1364682620300262 | The latest version of the International Reference Ionosphere is evaluated for ionospheric total electron content over China during a high solar activity phase of 2014 . TEC is derived from observations by the GNSS receiver network of Crustal Movement Observation Network of China . IRI 2016 uses the NeQuick option for the topside electron density profile . The comparisons shows that IRI 2016 underestimates GPS TEC slightly in spring and winter but overestimates slightly in summer and autumn at the mid latitudes of 35 | There is an obvious winter anomaly for GPS TEC in 2014 while it is not for IRI 2016. IRI 2016 has a good description of the ionosphere at mid latitudes of 35o45oN where the RMS of TEC is about 5 TECU. For the ionosphere of 15o35oN IRI 2016 estimates GPS TEC inaccurately in spring and winter and the RMS of TEC can be large as 33 TECU and 26 TECU respectively. The description of nighttime enhancement of ionosphere by IRI 2016 is inaccurate in 2014. |
S1364682620300274 | Thermospheric mass density estimates from in situ observations along satellite orbits are difficult to validate due to their inherent spatiotemporal sparse nature and difficulties related to drag force modeling and estimation of actual mass density state . Current upper atmospheric models are unable to accurately represent the actual thermospheric variability and in situ observations are far to fulfill the minimum requirements in practical applications . In this manuscript the new Thermospheric Mass Density Model is based on the fit of solar flux annual Local Solar Time and magnetospheric proxies into the Principal Component Analysis of 13 years of accelerometer based mass density estimates derived from the GRACE mission . We employ the NRLMSISE 00 model and estimates from APOD Swarm C and GRACE satellites and assess the new model including statistical analyses and a Precise Orbit Determination scheme . We compare 2 years of APOD and Swarm C estimates and study the dynamic orbit propagation of the 3 missions under different mass density input schemes and different magnetospheric activity conditions . The results with TMDM show similar differences in the dynamically propagated orbits from NRLMSISE 00 and in situ observations . The statistical analyses show that NRLMSISE 00 overestimates about 20 and TMDM underestimates about 20 the in situ observations . | A new Thermospheric Mass Density Model is presented and assessed by NRLMSISE 00 model GRACE Swarm C and APOD observations. The performance of TMDM is assessed in a dynamic orbital propagation analysis with similar deviations than that of NRLMSISE 00 and in situ estimates. The statistical analysis shows that NRLMSISE 00 overestimates about 20 and TMDM underestimates about 20 the in situ observations. |
S1364682620300286 | During the American solar eclipse on 21 August 2017 the GNSS network was applied to record the ionospheric responses . Following the lunar shadow the TEC depletion emerged over the eclipse path . After the eclipse end the depletion in the north gradually disappeared and then the TEC enhancement emerged . The depletion in the south has continued for a long time . A sharp area between the enhancement and depletion regions appeared at 27N latitude . Moreover the depletion region were moving to south with larger and larger TEC decline after the eclipse maximum . The TEC over four selected places with same latitude and different eclipse obscurations is presented . Interestingly the recovery periods of these TEC values are similar . The | The eclipse induced depletion was moving to south with larger and larger TEC depletion after eclipse maximum. A sharp area between the enhancement and depletion regions appeared at the latitude of 27 N. The fountain effect and eclipse induced thermospheric winds may play an important role for the rare phenomena. |
S1364682620300298 | In this study the trend of annual and monthly rainfall and trend of maximum and minimum temperature of the month have been detected . The presence of trends in annual rainfall time series are detected and evaluated using linear regression Mann Kendall test with Sen s slope estimator and Innovative Trend analysis . Results of trend analysis by LR M K and ITA methods show close agreement . An inverse distance weighting method in Arc GIS is used for developing spatial distribution of the trends over the entire study area of Sabarmati River basin India . Result of the monthly rainfall shows reducing trend in the June month and shows increasing trend for the month of September in the study area . This is indicative of tendency of late starting and late vanishing of the monsoon season . Maximum temperature in the basin in winter months show reducing trend while in summer months temperature show increasing trends . Results shown shifting of summer season extending to the monsoon months . The Land Use Land cover is examined for regional influential linkages to climate change . The change in the seasonal climate bears significance for its inferences in agriculture field and water resources field for fulfilling the demand from available water resources in the river basin . | Trend is detected for Hydro meteorological parameters in Sabarmati River basin in the state of Gujarat India. Trend of the Annual and monthly rainfall maximum and minimum temperature for each month is detected and evaluated and Spatial distribution of it is represented and linked to Land use Land cover in the basin. The Seasonal Climate Transference chart for Sabarmati river basin is developed. |
S1364682620300304 | The study analyses the delayed occurrence of the F region ionospheric manifestations like peak vertical drift and Equatorial Spread F onset in summer solstice of low solar activity years using the ionosonde data at the magnetic equatorial station Trivandrum and Republic of China Satellite 1 data . The analysis reveals the unambiguous role of the time of ionospheric F region zonal plasma drift wind reversal in modifying the above mentioned phenomena . The direct control of equatorial Spread F onset by the F region drift wind reversal is clearly established on a day to day basis in summer season . The role of the time of zonal wind drift reversal in modulating the ESF onset is examined quantitatively by exploring its effect on the growth rate of Rayleigh Taylor instability . Further the study brings out the solar activity variation of the time of F region zonal plasma drift wind reversal for all seasons . The results highlight the need to have systematic neutral wind measurements to better address the enigmatic and multi dimensional problem of equatorial Spread F day to day variability . | Ionospheric F region vertical drifts are observed to be delayed in summer months for low solar activity conditions. Role of F region wind reversal time in modulating the time of peak vertical drift and ESF onset is brought out. The study emphasizes the need to have systematic F region wind measurements for Equatorial Spread F prediction purpose. |
S1364682620300328 | The optical depth at 45 and 90GHz have been obtained from calibration data of two solar radio telescopes located in El Leoncito Astronomical Complex during the years 20122013 . The observed period and the temporal resolution of the measurements is sufficient to show seasonal patterns . Using the precipitable water vapor content obtained with a Sun photometer for aerosols measurements it was found a good correlation of PWV with the optical depth in both frequencies . With the water vapor content and data from a meteorological station the atmosphere over CASLEO was modeled using ATM 2009 an Earths atmospheric model . The results of the model allows to evaluate the range of optical depth measurements and to predict the contributions from H | Atmospheric absorption at 45 90 GHz correlates with precipitable water vapor. Atmospheric models used to predict the contributions of water vapor and oxygen. Refinement of atmospheric models using instruments operating in several frequencies. |
S136468262030033X | In this study the Weather Research and Forecasting model with Chemistry is applied to compare the simulated dust content and extinction coefficients from the Goddard Chemistry Aerosol Radiation and Transport the Air Force Weather Agency and University of Cologne dust emission scheme available in WRF Chem . The observations made by the AErosol RObotic NETwork and Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observations are used to assess the model performance during the summer of 2006 over northern Africa . The results highlight that all the three schemes reproduce broadly the observed spatiotemporal distribution of dust content and extinction profile over northern Africa . However differences exist in extent and intensity between the three emissions schemes and observations . All the three dust emission schemes reproduce the daily variation of the major dust events observed from the AERONET stations over northern Africa but failed to capture correctly the spatial distribution of the maximum zones of observed dust content by CALIOP . It is found that the simulated dust extinction profiles overestimate broadly the observation from CALIPSO in terms of vertical extent and magnitude over northern Africa . Our results reveal significant differences between the three schemes . These differences between the schemes could be related to the calculation of the threshold wind speed in each scheme which indicating the necessity to continue improving these dust emission schemes in the WRF Chem model to better reduce uncertainties in the representation of dust plumes . | The GOCART AFWA and UoC scheme reproduce broadly the observed AOD and extinction coefficient over northern Africa. There are significant differences between the three schemes GOCART AFWA and UoC results over the Sahara and Sahel regions. The simulated dust extinction profiles overestimate largely the observation from CALIPSO over northern Africa. |
S1364682620300341 | Long term natural and anthropogenic aerosol characteristics over the United Arab Emirates are investigated in this study . Aerosol characteristics were analyzed using data from the Moderate Resolution Imaging Spectroradiometer local meteorological stations and the Aerosol Robotic Network ground based station during 20062015 . AOD values significantly increase during the spring and summer seasons and are associated with dust loading during major dust events . The mean annual variation of aerosol loading indicates about a 4.32 and a 11.36 change in the AOD and ngstrm Exponent respectively during the study period . Monthly trends show larger AOD and AE variability 5.4 and 37.8 respectively with higher aerosol concentrations during the summer . In general from November to March an upward trend in aerosol characteristics is observed from 2011 to 2015 compared to 20062010 . In contrast a neutral to weak decrease in AOD measurements are observed during AprilSeptember . Overall this trend variability is sustained by natural aerosol emissions throughout the year . Meanwhile a significant increase in AE was measured from May to August of 20112015 compared to 20062010 . This is an indication of an increment of anthropogenic emissions from 2011 to 2015 . A correlation between several meteorological parameters and MODIS measurements was performed to investigate the effect of local meteorological conditions on AOD from 2006 to 2015 over the UAE . Some statistical correlation was observed between AOD wind speed and air temperature . A weak correlation was observed between temperature relative humidity and AOD while a strong correlation was observed between wind speed and AOD . Dry soil formed due to a lack of rainfall along with high summer temperatures and high speed winds which stimulate dust aerosol loading and lifetime in the atmosphere . Aerosol characteristics including dominant aerosols were identified over the UAE using the Mezaria AERONET station . Air mass flow towards the UAE from the North West and West directions moves over highly polluted regions and desert areas . Coarse mode aerosol particles dominate over the UAE during MarchJune associated with the dust season while a high loading of fine mode particles is mostly observed during SeptemberJanuary . | Aerosol mixing and loading over highly urbanized semiarid countries. Aerosols analysis using MODIS AERONET and meteorological data. Seasonal variation of aerosol over United Arab Emirates during 20052015. Dominant aerosols and particles characterization. Effect of local meteorological conditions on aerosol loadings. |
S1364682620300353 | Wind temperature relative humidity and aerosol mass concentration were monitored simultaneously in Wuhan China . Several observations were found after analyzing the physical fields of these data . It was obvious that weak pressure and saddle patterns occurred during fog haze episodes . An inversion layer occurred before heavy fog haze events and became thicker during fog haze events . The boundary layer structure index was relatively higher during fog haze days and had a significant negative correlation with the planetary boundary layer height and turbulence parameters . Wind speeds were generally less than 5m s and rarely exceeded this speed on the selected polluted days . Turbulence variation characteristics had special representations especially before fog haze events . Turbulence intensities always reached abnormal peak values before fog haze processes while the intensities remained steady before and during pollution processes with low relative humidity . Both the turbulence kinetic energy and momentum flux decreased to near zero before heavy fog haze processes . Momentum flux often presented abnormal disturbances before heavy fog haze processes . These disturbances were often in an active phase before and during pollution processes with low relative humidity a situation that is not similar to fog haze events that maintained high relative humidity . There was a feedback mechanism between solar radiation and aerosol mass concentration and the occurrence of turbulence anomalies may be related to the regulation of atmospheric circulation by wave flow interaction . The results presented in this study suggest that the turbulence parameters which display anomalies before the occurrence of heavy fog haze processes under the background of inversion layers and stable atmospheric patterns can serve as a means of predicting disastrous weather conditions such as fog haze pollution . | The importance of anticyclonic circulation pattern in pollution process. The relationship between turbulence parameters and boundary layer. Turbulent activity is often very weak prior to the heavy pollution. Combination analysis of different scales for circulation and boundary layer. |
S1364682620300365 | In order to understand the air quality and plausible sources of atmospheric pollutants over the Emirate of Abu Dhabi a detailed analysis is performed by utilizing three years of simultaneous measurements of various gaseous pollutants such as SO | Assessment of atmospheric constituents over EAD region for the first time. Transport of atmospheric pollutants is observed to be from north westerly direction. Linear relationship is observed between ozone and temperature. |
S1364682620300377 | This study aims to investigate the behaviors of the potential earthquake precursors such as Total Electron Content daytime nighttime Land Surface Temperature and aerosols before and after the 2013 Mw 7.7 Awaran earthquake . TEC values were obtained from Global Positioning System measurements and LST and aerosol values were retrieved from Moderate Resolution Imaging Spectroradiometer instrument aboard the Terra and Aqua satellites respectively . In order to detect the anomalies moving median method was used in TEC analyses and 2 interval was utilized in LST and Aerosol Optical Depth analyses as anomaly indicator . TEC anomalies were identified 3 days and 5 days before the earthquake . In daytime nighttime LST analyses three regions of interest for spatial analyses were determined including epicenter 10km impact area around the epicenter and Modified Mercalli Intensity 7.5 contour which was presented in the United States Geological Survey s shake map . Different anomalous days of LST were observed from these three regions of interest . In AOD analysis only MMI 7.5 contour was considered due to its low spatial resolution . The anomaly in AOD values was observed on 29.09.2013 5 days after the earthquake . However the abnormal behavior of AOD on 21.09.2013 was consistent with GPS TEC anomaly . Furthermore considering daytime nighttime LST values on epicenter and 10km impact area we observed a systematic increase culminated near the earthquake event and a decrease after the earthquake . On the contrary a systematic decrease and then increase of the AOD values were identified . The obtained results showed that TEC LST and AOD were important potential precursors for Earthquake prediction however further developments on methods data types and statistical analyses are still required . | GPS TEC daytime nighttime LST and MODIS aerosols were examined considering Sep 24 2013 Pakistan Earthquake. TEC anomalies were identified 3 days and 5 days before the earthquake. Different anomalous days of LST were observed from three regions of interest. The anomaly in AOD values was observed 5 days after the earthquake. Abnormality behavior of AOD 3 days before the earthquake was consistent with GPS TEC anomaly. |
S1364682620300389 | We analyze fluctuations of the magnetic field in the solar wind registered by the ACE satellite in the L1 Lagrangian point and the ULF waves observed with ground magnetometers at high middle and low latitudes during 84 intense substorm events . Our goal is to establish possible connections between ULF oscillations observed simultaneously in the different parts of the solar windmagnetosphereionosphere system during substorms . Our analysis reveals that there is a good correlation between oscillations with frequencies less than 1 mHz observed in the solar wind and in three different latitudes during strong substorms . In particular we show that the dominant frequencies of the waves observed on the ground at high middle and low latitudes are approximately the same the waves with frequencies of 0.450.55mHz and 0.750.80mHz are the most often seen in high middle and low latitudes and in the solar wind . Therefore we conclude that there is a strong coupling between the Earths magnetosphereionosphere system and the solar wind in the frequency range below 1mHz mediated by the disturbances in the magnetic field . | We perform statistical analysis of the ULF waves detected during substorms in the solar wind and on the ground at high mid and low latitudes. We found that in 28 out of 84 considered substorm events the waves with almost the same frequency. mHz were detected in all locations. ULF waves with frequencies 0.450.55mHz and 0.750.80mHz are common during substorms and during their respective preceding quiet times. The magnitudes of ULF waves at low latitudes are larger than the magnitudes of ULF waves at mid latitudes. The occurrence of ULF waves at middle and low latitudes correlate in time with variations in the. index. |
S1364682620300390 | In the theory of wave propagation in near Earth space there is a long standing but still unsolved problem this is the problem of whistler exit to the ground after passing through the magnetospheric trajectory . Snells law forbids exit of a wave to the ground if the angle between the wave normal and the vertical is outside the penetration cone which is almost always true at least for middle and low latitudes . However whistlers are often recorded at ground stations where they were first discovered . Most of the previous theoretical works considered the exit of whistlers to the ground as a stationary problem taking the wave field in the form | Whistler reflection from the ionosphere and exit to the ground has been studied. The features of the process are revealed in the frame of a non stationary 2D problem. Equation for the EM field vector potential valid in plasma and in vacuum is derived. Its numerical solution with initial conditions as a localized wave packet is found. An incident whistler wave packet feeds the Earth ionosphere waveguide by EM emission. |
S1364682620300419 | The influence of a certain type of tropospheric factors on the appearance and formation of noctilucent clouds at mid latitudes is studied by utilizing a method of construction and analysis of synthetic weather maps . The method is based on a cartographic comparison of satellite images of large fields of noctilucent clouds over most of northern Eurasia and standard meteorological maps for the same territory . The time of obtained satellite images and meteorological maps coincides within up to half a day . Based on the full set of synthetic weather maps constructed for the 2015 summer season it is statistically shown that in almost all cases the localization of noctilucent clouds fields is associated with the evolution of a number of typical weather processes in the troposphere . The most pronounced weather processes have been associated with the movement of cyclones and cold fronts the development of occlusions and extensive thunderstorms . A general explanation of the revealed facts is proposed which is based on the influence of internal gravity waves arising in the troposphere on the cloud formation in the upper atmosphere . Prospects for further research on tropospheric mesospheric interactions are considered . | Analysis of satellite images noctilucent clouds and weather maps is proposed. A link between the formation of noctilucent clouds and weather processes is shown. The influence of tropospheric processes can be explained by internal gravitational waves. |
S1366554518300218 | In this paper we study a shore power deployment problem in a container shipping network . The aim of the problem is to develop a subsidy program for a government that achieves the utmost reduction of at berth emissions from ships in the network . We formulate the problem as a mathematical model that captures the involved relationships among the government container ports and shipping lines . The model is hard to solve because it involves a multi phase process that does not have a closed form solution . To solve the problem we develop a tailored labeling algorithm . Extensive numerical experiments are conducted and the results demonstrate the applicability and efficiency of the solution method for solving practical instances . The results also demonstrate that the solutions delivered by our algorithm to the problem can significantly reduce the at berth emissions from ships in the shipping network . | Propose a novel shore power deployment problem for government. Prove the problem is NP hard. Propose a labeling algorithm that solves the problem to optimality. |
S1366554518300656 | Emergency supply of blood in disasters is a crucial task for humanitarian aid . In this paper we present a bi objective robust optimization model for the design of blood supply chains that are resilient to disaster scenarios . The proposed two stage stochastic optimization model aims at minimizing the time and cost of delivering blood to hospitals after the occurrence of a disaster while considering possible disruptions in blood facilities and transportation routes . A Lagrangian relaxation based algorithm is developed that is capable of solving large scale instances of the model . We apply this framework to a real case study of blood banks in Jordan . | A bi objective two stage robust optimization model is proposed for the design of resilient blood supply chains. It aims at minimizing the time and cost of delivering blood to hospitals after a disaster. It considers stochastic disruptions in collection centers blood banks and transportation routes. A Lagrangian relaxation based algorithm is developed that is capable of solving large scale instances of the model. |
S1366554518304538 | To derive conditions for manufacturer and retailer to implement trade in policies voluntarily and identify the optimal channel format for trade in we construct traditional retail channel model and dual channel model under two scenarios without trade in and with trade in . We find that the retailer would implement trade in policy voluntarily in traditional retail channel only if old customers market share exceeds a certain threshold . Interestingly the result is opposite in dual channel case . The traditional retail channel and the dual channel could be the optimal choice for implementing trade in respectively depending on different value ranges of customers acceptance of direct online channel . | The traditional retail models and the dual channel models with without trade in are constructed. We examine the conditions for manufacturer and retailer to implement trade in policies voluntarily. We identify the optimal channel choice for implementing trade in policies. |
S1366554518310639 | This study investigates a problem regarding simultaneous allocations of berths quay cranes and yards in transshipment hubs . Transshipment and import export activities general quay crane assignment decisions and productivity losses incurred by quay crane interference are considered . A mixed integer programming model is proposed to minimize the total cost including speed up cost delay cost penalty cost of vessels and operational cost on container loading and unloading . An iterative heuristic is developed to solve the proposed model . Extensive numerical experiments are conducted to validate the effectiveness of the proposed model and the efficiency of the algorithm . | Study integrated model for discrete berth allocation quay crane assignment and yard assignment problem. Consider both transshipment activities and import export activities. An iterative heuristic is developed to solve the model on large scale instances. Computational experiments are conducted to verify the effectiveness of the algorithm and model. |
S1366554518311086 | In this study we propose a new schedule based itinerary choice model the mixed itinerary size weibit model to address the independently and identically distributed assumptions that are typically used in random utility models and heterogeneity of passengers perceptions . Specifically the Weibull distributed random error term resolves the perception variance with respect to various itinerary lengths an itinerary size factor term is suggested to solve the itinerary overlapping problem and random coefficients are used to model heterogeneity of passengers . We also apply the mixed itinerary size weibit model to a train scheduling model to generate a passenger oriented schedule plan . We test the efficiency and applicability of the train scheduling model in the south China high speed railway network and we find that it works well and can be applied to large real world problems . | A model is developed for both stochastic passenger assignment and train scheduling. The mixed itinerary size weibit model is applied to the passenger assignment module. An iterative method is introduced to efficiently solve the resultant model. The model is tested on a real world high speed railway network in Southern China. |
S1366554518311256 | Navigation via the Northern Sea Route requires specific vessels in comparison with the Suez Canal Route . We develop a profit decision model that defines the best option mixing the shipping lane and the ice class of the vessel for oil producers operating in the Russian Arctic zone . The effects of the Brent barrel price bunker cost and ice thickness are analyzed . The best option depends in fact on the strategy implemented by the shipper . For instance the solutions of a profit focused strategy or of a cost oriented strategy are different | Sailing though the NSR versus the SCR saves distance but not always time. OW 1A and 1AS ice class vessels do not have the same level of revenue. Ice thickness impacts directly the navigability of the NSR. Brent value and bunker cost impact the choice of the vessel. The best option depends on the strategy based on climate and economic factors. |
S1366554518313115 | We review recent studies on transportation network performance under perturbations . Three representative concepts relating to network performance are covered reliability vulnerability and resilience . With an overview of the definitions and the quantitative indices of these three concepts we analyse and compare their similarities and differences in the context of transportation . These concepts differ from each other in terms of focus measurement and application scenario . Numerical examples are conducted to assess these concepts under different perturbation scenarios . The results indicate their rationale in reflecting network performance under perturbations yet their outputs differ . Moreover the relationship among the three concepts is intuitively illustrated by the analysis results . | Review recent studies on reliability vulnerability and resilience of transportation network. Definitions quantitative indices and analyses of the three concepts are overviewed. The characteristics of and the relationship among the three concepts are investigated. We provide remarks on the foci measurements and applications of the three concepts. |
S1366554518314285 | This study investigates a joint optimisation of routing and truck deployment for a small package shipping company . Bus tour based services are provided to collect express packages at customer bases . The objective of the optimisation problem is to minimise the average waiting time for packages stored at the customer bases . We first propose a mixed integer nonlinear programming model . The proposed formulation is linearised and made solvable by an off the shelf mixed integer linear programming solver . For solving larger instances of the problem we propose two optimisation approaches that can obtain near optimal solutions a local branching based method and a particle swarm optimisation based method . We conduct numerical experiments to validate the effectiveness and efficiency of the proposed solution methods . The results indicate that both methods can obtain optimal solutions quickly for most of the small scale instances . For medium size instances the local branching based method performs best and the PSO based method outperforms the others for large size instances . | A joint routing and truck deployment problem for small package shipping company. A mixed integer nonlinear programming model is proposed. A local branching based method and a particle swarm optimisation based method. Experiments are conducted to demonstrate the effectiveness of the methods. |
S1366554518314753 | This paper considers a bi modal traffic corridor with a highway and a transit line where car available travelers tend to be more sensitive to crowding than car unavailable travelers in transit vehicles . Modal spilt and departure time choices of heterogeneous travelers are considered . Two capacity design problems namely total travel cost minimization with budget constraint and total system cost minimization with budget and equity constraints are studied . It was found that when there is a construction operational technology improvement for one traffic mode the cost for its unit capacity reduces and its optimal total investment may increase . | Traffic corridor highway vs. transit for travelers with without cars is studied. Critical values of transit capacity are derived for a bi modal traffic corridor. Highway and transit mode can be both complementary and substituting. Jevons paradox exists when transport technology improvement is considered. |
S1366554519300754 | Emergency medical services systems equipped with both advanced and basic emergency vehicles often dispatch both types of vehicles to one call which is called multiple response . Multiple response allows for faster response times at the potential cost of making more vehicles unavailable for service . To evaluate the value of multiple response we formulate a Markov decision process model that dynamically determines which type of vehicle to dispatch based . We show that the optimal policies are class separable . Numerical experiments demonstrate that multiple response can significantly improve system performance when patients health needs are uncertain . | We study how to route ambulances to patients. There are two types of ambulances that provide different levels of patient care. At the time of dispatch there is uncertainty regarding which type of ambulance a patient needs. We study when to send a single ambulance and when to send multiple ambulances. The model can inform decisions in tiered emergency medical services. |
S136655451930081X | The Vehicle Routing Problem with Selective Backhauls aims to minimize the total routing costs minus the total revenue collected at backhaul customers . We explore a VRPSB under uncertain revenues . A deterministic VRPSB is formulated as a mixed integer programming problem and two robust counterparts are derived . A novel method to estimate the probabilistic bounds of constraint violation is designed . A robust metaheuristic is developed requiring little time to obtain feasible solutions with average gap of 1.40 . The robust approach studied demonstrates high potential to tackle the problem requiring similar computing effort and maintaining the same tractability as the deterministic modeling . | A VRPB under uncertainty is analyzed for first time. Four different methods are compared to estimate probability of constraint violation. An efficient metaheuristic provides high quality solutions for large instances. |
S1366554519301462 | This paper studies a multi customer joint replenishment problem with districting consideration which is of particular importance to a company that outsources its transportation and delivery operations to a third party logistics service provider . To solve the problem we first propose an innovative search algorithm for solving the traditional multi customer joint replenishment problem in a given zone . Then we design a GA based framework to handle the corresponding districting problem based on the performance of each district evaluated by using the proposed search algorithm . The proposed methodologies are demonstrated by using an example of solving MJRPDC for a bank . | Districting consideration is successfully integrated with the multi customer JRP. This study is vital to a company outsourcing logistics to a 3PL service provider. Our numerical experiments are based on a real life example in a bank system. An effective GA based algorithm is proposed for solving the problem. Managerial insights provide baseline information before contract negotiation. |
S1366554519301486 | This study investigates a multi depot multi trip vehicle routing problem with time windows and release dates which is a practical problem in the last mile distribution operations . This problem aims to design a set of trips for the fleet of vehicles supplied by different depots for minimizing total traveling time . It addresses some realistic considerations such as the customers time windows and the release date of customers packages . The problem is formulated as a mixed integer programming model . A hybrid particle swarm optimization algorithm and a hybrid genetic algorithm are developed to solve this problem . Extensive numerical experiments are conducted to validate the effectiveness of the proposed model and the efficiency of the proposed solution methods . The experimental results show that our proposed algorithms can obtain near optimal solutions for small scale problem instances and solve some large scale instances with up to 200 customers 20 depots and 40 vehicles in reasonable computation time . | A multi depot multi trip vehicle routing problem with time windows and release dates. An MIP model with the objective of minimizing the total traveling and service time. Solve some large scale instances with up to 200 customers 20 depots and 40 vehicles. |
S1366554519301784 | In this paper we address a green delivery pickup problem for Home Hemodialysis Machines categorized as scarce commodities . The system supplies the HHMs either from the central depot of the company or from the individual owners . Based on the sharing economy concept the individuals who own the HHM devices can involve in this home health care system and share them with others through the fleet of the company to make money . After delivery of portable HHM devices to the clients they will be collected disinfected and reallocated to fulfill the demands of the other customers . Moreover respecting the environmental concerns the vehicles fuel consumption and consequently the GHG emissions are realistically assumed as a function of the vehicles load such that the company and especially the individual owners contribute to reducing GHG emissions in addition to the primary economic motivations . Current research provides a bi objective mixed integer linear programming model which seeks minimizing total system cost and total carbon emissions . In order to solve the problem Torabi and Hassinis technique is applied and then a multi objective meta heuristic algorithm self learning non dominated sorting genetic algorithm is developed for medium and large sized problems . Finally the application of the problem is investigated by a real case study from the healthcare sector . Numerical analyses indicate that the proposed green sharing enabled model has a meaningful impact on both operational level logistics determinations as well as the environmental important attainment indicators . As notable savings are guaranteed in terms of total system cost and emission the proposed model has a great potential to provide the item sharing activities with a proper sustainable solution . | Integrating the sharing economy concept into the green delivery pickup problem. System cost and GHG emissions are simultaneously minimized by a bi objective model. A real case from the healthcare sector shows the applicability of the model. A self learning NSGA II is developed to solve the proposed bi objective model. The positive impact of sharing economy on eco efficiency is demonstrated. |
S1366554519301838 | This paper envisions a mixed network with autonomous vehicle expressways and non autonomous local streets in the future where a trip may consist of both the AV self driving part and the manual driving part . A linear traffic corridor approach is adopted where AV expressways and non autonomous streets are in parallel and are connected through the entrance exit . This mimics the intermediate future where AV expressways may be initially deployed along major corridors . We model and analyze road users route choice in such a mixed network . We also examine how AV expressways are integrated with the local streets can affect system performance . | This paper envisions a mixed network with AV lanes and non autonomous local streets. This paper models AV route choices under both User Equilibrium and System Optimum. This paper derives cordon based tolling schemes to achieve System Optimum. This paper explores how AV expressways should be integrated with local streets. |
S1366554519302005 | This study investigates a supply chain financing system with one supplier and one emission dependent and capital constrained manufacturer . Unlike the traditional SCF the manufacturer borrows two loans to execute the ordering decision and make a low carbon investment respectively . We derive the equilibrium strategies of the supply chain members under partial credit guarantee and a combination of trade credit and PCG and compare with that under a benchmark . There exists a unique coefficient of credit guarantee for the supplier to decide whether to provide a trade credit . Numerical studies and extension are discussed to obtain more managerial implications . | Investigate an emission dependent supply chain with capital constraint. Consider partial credit guarantee PCG and TPCG combine trade credit with PCG . Derive equilibrium strategies under a benchmark and the two financing schemes. Find that supplier prefers to provide trade credit when credit guarantee is higher. |
S1366554519302406 | The joint optimisation of investments in capacity and repair capability of production and logistics systems at risk of being damaged is an important aspect of supply chain resilience that is not sufficiently addressed by state of the art modelling approaches . Furthermore logistical issues of procuring repair resources impact speed of recovery but are not considered in most existing models . This paper presents a novel multi stage stochastic programming model that optimizes pre disruption investment decisions as well as post disruption dynamic adjustment of supply chain operations and allocation of repair resources . A case study demonstrates how the method can quantify the effects of pooling repair resources . | Joint optimisation of supply chain capacities repair capabilities supply chain operations and repair resource logistics. Scenario tree generation method considering the risk of failure propagation. Multi stage stochastic programming model for initial network capacities and dynamic network flows. Case study quantifying the costs and benefits of pooling repair resource procurement. |
S1366554519302662 | We consider the storage space allocation problem at an inland bulk stockyard which aims to find an effective way to store the shapeless materials . Due to the specific storage and handling means in the stockyard unloading stacking and reclaiming operations need to be scheduled in an integrated manner . Viewing the space of each stock pad in the yard as a series of unit slots we first develop a novel MIP formulation which can avoid generating scattered small fields . We then decompose the model by exploiting the relationships among the above operations and develop a logic based Benders approach to solve it optimally . | An exact method for the storage space allocation problem in bulk material stockyards. A novel MIP formulation tackles the practical challenge of avoiding scattered small fields. Logic based Benders approach based on exploitation of operation relationships. Proposed method effectively solve realistic problem in short time. |
S1366554519302789 | This paper investigates the effect of carbon tariffs on global emission control . We propose a global supply chain model consisting of a retailer in an emission regulated country and supplier in a non emission regulated country . The equilibrium solutions are obtained and the effects of a carbon tariff on global emission control are studied . Through analytical study and numerical study we find that a carbon tariff does not necessarily reduce global emissions under certain circumstances . The paper discusses insights and the carbon tariff policy implications from this finding . | The effect of carbon tariffs on global carbon emission control is examined. Two specific strategic responses of supply chain managers are explicitly considered. Charging a carbon tariff does not necessarily reduce global emissions. Managerial implications for policymaking are presented via a numerical study. |
S1366554519303552 | We consider a freight transportation network model in which we can send goods with or without bundling . When we choose the bundling option we can send multiple goods after grouping into a bundle at the cost of one unit good however bundling and unbundling also incur costs . The model was originally developed to solve the problem of relocating empty containers in hinterland transportation but it also has an application in multimodal freight transportation . We investigate the complexity of the problem and develop an efficient heuristic that uses a network flow algorithm . | Analyze the computational complexity of the FTNPB on an arbitrary network. Develop an efficient heuristic for solving the FTNPB on an arbitrary network. Carry out intensive computing experiments to test our heuristic. Extend the model to the case where arbitrary number of flows can be bundled up to a given limit. |
S1366554519303722 | We extend the Traveling Repairman Problem by assuming a single truck which can stop at customer locations and launch drones multiple times from each stop location to serve customers . The problem is mathematically modeled several bound analyses are conducted to determine the maximum possible improvements in customer waiting times and an efficient hybrid Tabu Search Simulated Annealing algorithm is developed to solve the problem . The results of evaluations on several problem instances suggest that the system can yield considerable reductions in customer waiting time for a wide range of model parameters compared to the conventional delivery models . | We model a joint routing problem of a truck with one or multiple drones. We conduct several theoretical bound analyses on maximum possible savings. We develop a hybrid metaheuristic approach based on Simulated Annealing and Tabu Search to solve the problem. We assess the performance sensitivity of this system to a number of key parameters. We demonstrate the real world impact of our model by a case study in Massachusetts USA. |
S1366554519303734 | The rise of e commerce has increased the demands placed on pickup and delivery operations as well as customer expectations regarding the quality of services provided by those operations . One strategy a logistics provider can employ for meeting these increases in demands and expectations is to complement and coordinate its fleet operations with those of for hire third party logistics providers . Herein we study an optimization problem for coordinating these operations the time dependent profitable pickup and delivery problem with time windows . In this problem the logistics provider has the opportunity to use its fleet of capacitated vehicles to transport shipment requests for a profit from pickup to delivery locations . Owing to demographic and market trends we focus on an urban setting wherein road congestion is a factor . As a result the problem explicitly recognizes that travel times may be time dependent . The logistics provider seeks to maximize its profits from serving transportation requests which we compute as the difference between the profits associated with transported requests and transportation costs . To solve this problem we propose an adaptive large neighborhood search algorithm . The results of our extensive computational study show that the proposed algorithm can find high quality solutions quickly on instances with up to 75 transportation requests . Furthermore we study its impact on profits when explicitly recognizing traffic congestion during planning operations . | We discuss the time dependent profitable pickup and delivery problem. We introduce an ALNS heuristic to solve this problem. To reduce computation time a simple and approximate route evaluation is employed. We show that large size instances can be solved within a relatively short CPU time. This study discuss the effect of considering the time dependency in the planning. |
S1366554519303886 | We study blood supply network optimization considering disasters where only a small number of historical observations exist . A two stage distributionally robust optimization model is proposed in which uncertain distributions of blood demand are described by a moment based ambiguous set to optimize blood inventory prepositioning and relief activities together . To solve this intractable DRO with integer recourse an approximate way is developed to transform it into a semidefinite program . A case study based on the Longmenshan Fault in China validates that our approach outperforms typical benchmarks including deterministic stochastic and robust programming . Sensitivity analysis provides helpful managerial insights . | A stochastic blood supply network optimization considering disasters is studied. A novel distributionally robust model with integer recourse is formulated. A tractable approximate reformulation of min max min problems is proposed. A case study for the Longmenshan Fault in China is performed. Findings and managerial implications related to this problem are provided. |
S136655451930403X | A railway system plays a significant role in countries with large territorial dimensions . The Brazilian rail cargo system however is focused on solid bulk for export . This paper investigates the extreme performances of BRCS through a new hybrid model that combines TOPSIS with a genetic algorithm for estimating the weights in optimized scenarios . In a second stage the significance of selected variables was assessed . The transport of any type of cargo a centralized control of the operation and sharing the railway track pushing competition and the diversification of services are significant for high performance . Public strategies are discussed . | The paper investigates the efficiency of the Brazilian Rail Cargo System. The methodology combined TOPSIS with a genetic algorithm to build optimized scenarios. The significant attributes in scenarios of low and high performance were highlighted. Transport of any kind of cargo and shared railway are significant for the results. Competition and diversification are key elements for high performance. |
S1366554519304053 | By focusing on several critical speeds this paper proposes a simple and applicable method to seek the optimal speed for carriers . The results show that carriers will reduce ship speed if the saved fuel cost outweighs the incurred capital and operating costs . The measure of critical fuel prices at different critical speeds is powerful to examine the optimal speed . Meanwhile deploying extra ships and calling extra ports could be an optimal strategy for carriers in implementing slow steaming . The empirical result suggests that the optimal speeds for large ships will be higher than the ones for small ships . | A simplified method by focusing on several critical speeds to seek the optimal speed for carriers is provided. The paper shows that slow steaming can definitely reduce fuel consumption and the resulting GHG emissions. Adding ships and calling extra ports can be an optimal strategy for carriers in doing slow steaming. The measure of critical fuel prices at different critical speeds is an efficient way to determine the optimal speed. The optimal speed for large ships will be higher than the one for small ships. |
S1366554519304107 | We consider duopoly competition among transportation firms operating on a multi segment route and analyze the welfare consequences of different market structures in serial and parallel transport network structures . Travellers are concerned with both price and latency and may opt to avoid travel in the system altogether if conditions are insufficiently attractive . Firms simultaneously set prices to maximize their own profits . We derive the traffic flow consequences of duopoly monopoly price free and socially optimal scenarios for both the serial and parallel structures drawing comparisons regarding traffic flows prices and welfare . In extensions of the model we consider firms operating costs more than two firms and hybrid market structures . The results point to a higher overall social welfare desirability of parallel competition along multi segment transportation routes . Our study delivers important policy implications regarding the optimal route structure design . | We analyze the welfare consequences of serial and parallel transport network structures. We derive equilibrium for duopoly monopoly price free and social optimum scenarios. As extensions we consider operating costs more than two firms and hybrid structures. Compared to serial structure parallel structure leads to a higher overall social welfare. Our study delivers policy implications regarding the optimal route structure design. |
S1366554519304156 | Knowledge of spatial distributions of weight categorized truck flows in a region is critical to the understanding of movements of empty or partially loaded trucks and devising appropriate strategies to reduce empty or partially loaded truck flows and improve truck utilization efficiency in the region . However such disaggregated information can not be directly obtained from existing data sources and models . In this paper we propose a compact model for estimating weight categorized truck origindestination flows and link level truck counts by fusing several freight datasets . The proposed model minimizes the squared errors between the estimated and observed truck OD flows and link volumes considering the flow conservation of trucks and commodity weights . To illustrate a real world application of this model a case study is conducted to estimate the spatial distribution of empty or partially loaded truck flows into within and out of the State of Florida . With the case study results high production and attraction zones of empty or partially loaded truck trips are also identified . Such results can potentially inform freight planning and policy decisions to learn spatial patterns of empty or partially loaded backhauling truck flows and devise countermeasures to reduce such flows and improve freight transportation efficiency . This is particularly relevant to a terminal state such as Florida that has large volumes of back hauling truck flow . | Propose an optimization procedure to estimate weight categorized truck counts. Demonstrate an easy to use method for integrating freight datasets. Conduct a case study to estimate weight categorized truck counts in Florida. Explore scenarios to derive appropriate weightages for the optimization model. |
S1366554519304326 | Delivering commodities by ground vehicles to people in conflict zones risks the safety of humanitarian aid workers . Hundreds of aid workers are killed injured or kidnapped when delivering supplies on the road each year . We propose the humanitarian flying warehouse as a solution to these issues . The HFW is an airship that stays at high altitudes and uses unmanned aerial vehicles to deliver supplies . This innovation will enable safe and timely delivery to hard to reach populations in a manner that significantly exceeds the capacity of current practices . Crucially the HFW eliminates the motivations behind many delivery disruptions . These disruptions are caused by asymmetric commons dilemmas entities with different accessibility and power race to grab shared relief goods before others . The problem we address is the operation of HFW to make safe and timely delivery of critical items such as health supplies to the hard to reach populations . This study constitutes proof of concept for the HFW system in conflict zones through a multi objective mathematical model . The validity of the system is verified via comparative analysis with a ground based system in a realistic case study . | Proof of concept study for HFW system in conflict zones. Multi objectives model with the consideration of humanitarian principles. Epsilon constraint method is used to address conflicting objectives. The model is applied to the case study based on northeast Syria. Comparative analysis between HFW system and ground based UAVs system. |
S136655451930448X | In this paper we consider supply chain coordination with a revenue sharing contract and a linear quantity discount contract in a fashion supply chain with demand disruptions . The situation without demand disruptions is considered as the benchmark . In the benchmark we find that the RSC fails to coordinate the supply chain while the LQDC does . We also find that demand disruptions can promote supply chain coordination . We then find that in some cases the RSC fails to coordinate the supply chain whereas the LQDC can do so . | The RSC fails to coordinate the supply chain while the LQDC does under benchmark. The two contracts cannot fully coordinate the supply chain with demand disruptions. The LQDC coordinates the supply chain when demand increases or decreases greatly. The RSC can coordinate the supply chain when the demand increases slightly. The demand disruptions can promote the supply chain coordination. |
S1366554519304636 | Green products are gaining popularity because of their environmental friendliness compared with conventional products . This study examines a word of mouth diffusion problem of a newly launched green product and investigates the effects of consumers environmental awareness . Analytical results show that CEA significantly affects green product diffusion in terms of firms pricing strategies and market shares . The market structure also has effects on diffusing a green product the pricing strategies and environmental performance of diffusing a green product in a Bertrand competition market are different from those in a Stackelberg game market . When considering green design decision it is interesting to show that the green products price decreases with the increase of CEA which is contrary to the pricing strategy without green design . From the numerical study of the CEA featured WOM diffusion case we find that CEA featured WOM does not affect the pricing strategies of the green and conventional products but does have a significant impact on the market shares of both products . | We study a WOM diffusion problem of a new and innovative green product. Pricing strategies are proposed to help firms to diffuse green products. Green product diffusions in Bertrand competition and Stackelberg game markets are studied and compared. Green product design strategies are investigated for green product diffusion. WOM featured diffusion model is formulated to further study the green product diffusion problem. |
S1366554519304806 | The paper studies a closed loop supply chain focusing on managing scheduling and routing problems to achieve economical and environmental sustainability . Generally a logistic based green supply chain is studied to help multiple stakeholders . Here we investigate the CLSC to reduce the total transportation cost including carbon emission from a heterogeneous fleet with limited capacity . The forward chain includes manufacturers depots distributors collectors and customers . In the reverse chain the distributors collect the returned items and sort into three groups through quality screening and send them to the secondary chain facilities which one is fitted . This investigation is contributed by all the demonstrating issues through considering customers demand an extensive emission display and the vulnerability of an expanded convey of vehicles . The proposed model addresses four distinct environmental policies viz . cap carbon tax cap and purchase and cap and sale for carbon emission regulations . The model is formulated in the framework of mixed integer non linear programming and an exact approach is employed to obtain the optimal solution . The theoretical results of the model are verified through numerical examples . A comprehensive analysis is presented to monitor the rate of return products and various fleet transporting parameters . | Considers a novel closed loop supply chain with heterogeneous fleet. Develops and analyses carbon emission regulations mandated by Government. Analyses the conflict between transportation cost and carbon emission cost. Evaluates the performance of the multi objective model with a case study. |
S1366554519304855 | In this paper we propose a discrete model to investigate reliable location design with round trip transportation under imperfect information . The unique feature of this problem is that under each disruption scenario a customers outbound and inbound trips are different when she travels to obtain a service . The discrete model is formulated as a compact non linear integer programming problem and solved efficiently by a customized Lagrangian relaxation algorithm . Numerical experiments find that the discrete model performs well for small and medium scale problem instances . Sensitivity analyses reveal the impacts of several parameters on both the cost components and the optimal facility layouts . | Consider round trip transportation and the optimal try and error visiting strategy in reliable location design. Formulate a compact model for reliable location design with round trip transportation and under imperfect information. Propose an efficient customized solution approach based on Lagrangian relaxation. Compare the proposed customized algorithm and commercial solver. Reveal the effect of influence factors on optimal location design and cost components. |
S1366554519304909 | The third party platform channel has been widely used in addition to the traditional retail channel to sell products . In practice some third party platforms provide financing services to small businesses that sell products on them . However few studies addressed the capital constraint problem faced by a manufacturer who sells products through both retailers and third party platforms especially when considering the third party platforms lending service behavior . This research establishes a model where a capital constrained manufacturer sells products through a retailer and a third party platform and may pursue a financing strategy by borrowing from the third party platform the retailer or the bank . We investigate the impact of the third party platforms or retailers dual rolelending provider and channel participanton dual channel operational management and study the manufacturers financing strategy choices by comparing profits under different financing strategies . The results of our analysis show that for the manufacturer the 3PF strategy is always better than the BF strategy . Furthermore the manufacturer is more likely to prefer the RF strategy to the 3PF strategy as the channel competition increases or as the revenue sharing rate or unit production cost decreases . We also find that the retailers retail price increases as the revenue sharing rate increases if there is no capital constraint but it decreases under the BF and 3PF strategies . This indicates that the manufacturers financing behavior has a significant impact on the retailers retail price decision . We extend our model by considering random demand and find that these findings continue to hold when the potential demand equals its expected value . | The 3PF strategy is always better than the BF strategy. RF is more likely to be better than 3PF as the channel competition increases. 3PF is more likely to be preferred as the revenue sharing rate or unit production cost increases. Financing behavior affects the revenue sharing rates impact on retail price. |
S1366554519305678 | This study proposes an efficient deviation path algorithm for finding exactly k shortest simple paths without loops in road networks . The algorithm formulates the deviation path calculation process as repeated one to one searches for the shortest path in a dynamic network where only a node and a link are restored at each search . Using this formulation the proposed algorithm maintains and updates a single shortest path tree rooted at the destination . A re optimization technique lifelong planning A is incorporated into the algorithm to efficiently calculate each deviation path by reusing the shortest path tree generated at the previous search . To verify the efficiency of the proposed algorithm computational experiments were conducted using several real road networks and the results showed that the proposed algorithm performed significantly better than state of the art algorithms . | Efficient algorithm is proposed to find k shortest simple paths in road networks. A reoptimization technique lifelong planning A is incorporated to speed up the deviation path calculation process. The deviation path can be efficiently calculated by reusing the shortest path tree generated at the previous search. The proposed algorithm runs significantly better than four state of the art algorithms. |
S136655451930568X | This paper addresses an integrated relief network design problem for pharmaceutical items . The proposed bi objective model accounts for perishability of pharmaceutical items mobility of relief facilities and benefits from a cooperative coverage mechanism in designing the network . A minmax robust model is developed to tackle the demand uncertainty . Several numerical experiments are conducted to explore the performance of the robust model . Also by conducting a real case study useful managerial insights are derived through performing several sensitivity analyses . The numerical results reveal that using the minmax robust model enhances the pharmaceutical relief networks effectiveness and efficiency considerably . | Designing a pharmaceutical relief network under demand uncertainty and drugs perishability. Providing a framework agreement with suppliers using an option contract. Using a cooperative coverage mechanism for moving mobile pharmacies at post disaster. Developing a tailored minmax robust approach to deal with the demand uncertainty. Investigating a real case study and proposing several managerial insights. |
S1366554519305915 | Space allocation problem in container terminals is one of the yard management challenges in short term planning however the impact of container reshuffling to the SAP is neglected in much of the literature as well as in real terminal planning . This study focuses on the SAP that accounts for container reshuffling where the macro level impact of reshuffling is derived from discrete event simulation and integrated into mix integer programming model . Empirical approaches are developed to achieve a trade off between fast computation and good solutions . The result shows that ignoring reshuffling activities during planning will lead to overestimation on yard capacity . | The impact of container reshuffling is integrated with space allocation problem. A simulation model is developed to capture the relations between the reshuffling factors. The impact of reshuffling is approximated by a high dimensional interpolation method. Empirical approaches are explored to solve the problem. Experiment results show that the potential losses from ignoring reshuffling activities can be significant. |
S1366554519306477 | To improve the operational efficiency of e commerce warehouses multi location storage systems which means each stock keeping unit can be stored in multiple locations or a location can contain multiple stock keeping units have been developed and applied in practice . When orders are picked in a batch how to select the picking location from storage locations holding the identical stock keeping unit obviously affects how far the pickers must travel to complete the picking tasks . However few works have systematically studied how to optimize order batch picking from the perspective of different storage systems . This paper formulated the order batch picking optimization problems for three typical storage systems and developed the algorithm package including location interval distance algorithm location selection algorithm routing algorithm and order batching algorithm to tackle them . Our work is particularly capable to covering the situation of multi location storage system . The numerical experiment results show that the performance of the proposed algorithm combinations is satisfactory to solve the problems with different size both in solution quality and computation efficiency . The applicable algorithm combinations used in practice are also recommended by comparative analysis . Our study can provide valuable decision reference to warehouse managers for operating batch picking system especially under multi location scenarios efficiently . | Investigate order batch picking optimization problems from the perspective of storage system. Establish the order batch picking optimization model especially considering multi location storage systems. Propose an order batching optimization algorithm package to deal with multi scenarioproblems. Investigate the efficiency of each combination of algorithms and recommend the promising ones. |
S1366554519306702 | Most vehicle routing approaches disregard the need to refuel fleets . However planners search for opportunities to refuel at lower prices even if counter intuitively distant fuel stations need to be visited . We propose a novel mathematical formulation and develop branch and cut and matheuristic algorithms to efficiently tackle this problem . Results indicate that to minimize costs detour distances may increase up to 6 percentage points when fuel stations with lower prices are farther away from the depot . For practice these insights imply that current policies disregarding station location and or fuel prices along with myopic planning horizons may lead to sub optimal decisions . | A novel mathematical formulation considers different fuel prices in vehicle routing. The objective function minimizes the cost of fuel purchased at several fuel stations. New branch and cut and metheuristic algorithms efficiently solve the formulation. Instances are solved to perform a sensitivity analysis over fuel related parameters. Longer distances do not always mean larger fuel cost when fuel prices are considered. |
S136655451930691X | We develop game theoretic models to examine the manufacturers vertical integration strategies in a three tier supply chain with two suppliers one manufacturer and two retailers . The supply chain sells two quality differentiated products . We find that when quality is exogenous regardless of the existing supply chain structure the manufacturers choice of forward or backward integration strategy depends on the relative efficiencies of two products . When quality is endogenous however the existing supply chain structure does affect the manufacturers integration strategy decision . Although backward integration hurts the unintegrated supplier forward integration can lead to a win win outcome for the manufacturer and unintegrated retailer . | We consider a three tier supply chain selling two quality differentiated products. The supply chain consists of a manufacturer two retailers and two suppliers. The manufacturers either forward or backward integration strategy is examined. Endogenous quality positioning changes the manufacturers integration strategy. We discuss effects of up down stream supply chain structure on integration strategy. |
S1366554519307033 | Many multinational companies operate their business in both domestic and overseas markets with different logistics modes namely freight transportation by truck for domestic and short haulage transshipment by container for overseas . To effectively optimize these operations for the two types of logistics systems we propose an intelligent integration of external and internal transportation with the separation of drayage trucks and containers . The objective is to minimize the total cost which includes both fixed and variable costs . The fixed cost occurs when the drayage truck is incurred in integrating transportation and the variable cost is generated per travel distance increment . By dividing customers into different subsets and proposing a special penalty matrix we provide an intelligent model that integrates the internal and external container transportation problems . A customized genetic algorithm is proposed . Based on the instances of real life data on 888 orders the results show that our approach can reduce the overall cost by 16.8 . | We propose an intelligent logistics system that serve both internal and external demands. We integrate internal and external transportation with separation mode. We formulate a mixed integer programming model to solve this new problem. We adopt a customized genetic algorithm to solve the MIP. |
S1366554519307252 | Focusing on the price issue in shared parking two auction based pricing strategies are designed in a double environment covering parking suppliers and demanders . A novel uniform price strategy is proposed to set unique transaction prices for winning participants it is in contrast with the differential price strategy which sets differential transaction prices . The DPS and UPS are compared from the perspective of parking platforms payoff and participants utilities theoretically and numerically . It shows that the DPS is superior to the UPS in terms of parking platforms payoff whilst the UPS outperforms the DPS in terms of participants utilities . | Rational and innovative uniform price strategy UPS for shared parking price. Comparison between proposed UPS and conventional differential price strategy DPS . Alternative options for policymaker with UPS and DPS in view of certain preference. |
S1366554519307859 | A multiple delivery points service that matches a vehicle to distribute goods from a merchant to multiple retailers is a novel and important business model in freight O2O platforms . Thus far the distribution matching strategy that does not consider the pricing strategy has found wide use in practice . In this study using mixed integer linear programming we propose an assignment matching strategy that jointly optimizes the matching and pricing strategies with optimal delivery routes to multiple retailers . Based on practical data from Zallsoon a famous freight O2O platform in China the results show that the proposed assignment matching strategy has the potential to improve the pickup distance by 7581.81 . Further the choice of pricing strategies could contribute 6093.33 in improvements to the transportation cost for cities with various order structures and promotion levels . Finally the high starting fare and low extra charge rate strategy is preferred for high tier cities whereas the step toll strategy is recommended for low tier cities . | Propose an optimal assignment matching strategy for a freight O2O platform. Jointly optimize the delivery route and pricing strategies for multiple delivery points service. Suggest HSLR strategy for high tier cities whereas and ST strategy for low tier cities. Explore the impact of customer segmentation on the selection of pricing strategies. |
S1366554519308385 | This paper comprehensively analyzes ships response strategy to emission control areas . By establishing mixed integer nonlinear programming models we obtain the optimal sailing pattern and evasion strategy selection . Furthermore the impacts of different factors on response strategy are discussed which deepens our understanding of the dynamic adjustment of decisions . The results show that for a total of 420 routes within the North American ECA ships will adopt evasion strategy on 39.05 routes and this ratio will decline slightly to 29.05 after 2020 . In addition evasion strategy will increase ships total pollution emissions resulting in less emission reduction . | Establish optimization models to obtain the optimal sailing pattern and evasion strategy. Quantitatively analyze the impacts of related factors on ships response strategy. Discuss the changes on ships evasion strategy selection before and after 2020. Analyze the impact of evasion strategy on ships pollution emissions. |
S1366554519308555 | Shipping industry is the backbone of global trade . However the large quantities of greenhouse gas emissions from shipping such as carbon dioxide CO | Propose a two stage model to predict and reduce fuel consumption for a dry bulk ship. Develop a random forest RF regressor for ship fuel consumption prediction. Develop a mixed integer linear programming MIP model to optimize ship sailing speed. 27 of fuel can be saved compared with the real situation of twelve days of continuous voyage. |
S1366554519308567 | New trade in services such as online trade in trade in on e commerce platforms and omni channel trade in are emerging due to the development of e commerce . To offer these new trade in services firms need to determine the optimal product price and rebate and decide whether to pay the rebate with a gift card or cash . To address these challenges for firms our paper considers a firm selling a new product to new consumers and offering a trade in service to replacement consumers . In addition we develop theoretical models to examine the optimal decisions in the cases of G and C and explore the optimal payment for the rebate . We reveal that G payment is a better choice for the firm only if the used product residual value is relatively low and the market size ratio between replacement and new consumers is relatively low otherwise the firm should choose C payment . Interestingly replacement consumers preferred trade in rebate payment leads a lower trade in demand than G payment and C payment may be harmful . In the extension we consider a firm with online and offline sales channels and different types of replacement consumers who own different used products and find that our main results regarding the optimal rebate payment still hold . Moreover we find that in the context of a used product with a relatively medium residual value firms with online and offline sales channels are more likely to choose G than firms with one sales channel otherwise firms are more likely to choose C . | Explore optimal trade in rebate payment from gift card and cash payments. Study product prices and trade in rebates in the cases of two payments. No one payment is always better for firms and replacement consumers. Cash payment leads a lower trade in demand than gift card payment. The main results still hold in the case of firms with O2O sales channels. |
S1366554519308804 | High capital intensity and reliance on debt financing are among the most prominent characteristics of the shipping industry . The corporate finance literature has documented that beyond a certain threshold leverage can hamper a firms ability to raise capital and as a result have a bearing on its corporate investment policy . The new more restrictive financing landscape in the shipping sector has put the management of capital structure on the spotlight as a key driver of investment policy financial health and thus firm success . In this paper we examine for the first time the link between the financing policy of shipping companies and their corporate investment decisions . We focus on the impact of deviations from target capital structure on mergers and acquisitions an increasingly important corporate growth vehicle for shipping companies with directly measurable outcomes . Deviations from optimal leverage display a strong association with the likelihood to consummate acquisitions deal size the financing method as well as the M A outcome . Higher debt levels are shown to have a negative effect on acquisitiveness and a positive effect on the quality of corporate investment a pattern with direct policy implications for shipping companies their management teams and shareholders . | We examine the impact of financial leverage on corporate investment outcomes in the shipping industry. Deviations from abnormal leverage affect the likelihood of undertaking acquisition investments. Deviations from abnormal leverage are also linked to deal size and financing mode. Overleveraged firms make better acquisition decisions. |
S1366554519308816 | We examine the cash holding decisions of global shipping firms in response to a change in geopolitical risk . Our results show that shipping companies significantly increase their cash reserves after GPR rises . The positive impact of GPR is more pronounced for firms with greater financial constraints . A further analysis shows that GPR positively and significantly affects dry bulk and container firms but has an insignificant impact on tanker and logistics firms . We also find that GPR positively affects the corporate cash decisions of Asian listed shipping companies but not those of other globally listed shipping companies . This study calls for policymakers to implement appropriate monetary and fiscal policies . | Shipping companies significantly increase their cash reserves in response to higher geopolitical risk GPR . The impact of GPR to the shipping industry is significant relative to other sentiment indices. The impacts of GPR depend on firm characteristics and types of shipping firms. Listed shipping firms in Asian countries are more vulnerable to a change in GPR. |
S1366554519309408 | Organ allocation is the most important decision amongst organ transplantation decisions thanks to the high demand of organs . This research develops a possibilistic programming model for a liver transportation and allocation problem considering medical uncertainty and tradeoff between quality metrics namely efficiency and equity . The model maximizes the survival rate of patients and minimizes the transportation cost and time . A novel hybrid interactive fuzzy optimization model is developed based on preemptive goal programming approach . Several numerical examples are taken from a real case study . The results demonstrate that the suggested algorithm outperforms the existing allocation policy considering both metrics . | A possibilistic programming approach is proposed for a liver transportation and allocation. The proposed model considers medical uncertainty as well as tradeoff between quality metrics in organ transplantation. The model aims to maximize the survival rate deliberating the most urgent need for liver transplantation and minimize the transportation cost and time. A novel interactive fuzzy optimization model is developed based on goal programming approach. The numerical results demonstrate that the suggested algorithm outperforms the existing allocation policy efficiency and equity metrics. |
S1366554519309524 | In the shipping industry forwarders can purchase a one stop service from an ocean shipping company or a dual ocean inland service from an OS company and an individual inland shipping company . Additionally the OS company can strategically decide whether or not to enter the downstream market for cargo canvassing which will form a co opetition relationship with incumbent forwarders . We investigate a strategy matrix based on the following two questions What kind of shipping service should be purchased by the forwarder Is it beneficial for OS company to enter the market We find that when the forwarders cargo canvassing effort level is low a dual service purchasing strategy will benefit both the stakeholders while market entry is a self interested behavior and hurts the forwarder . Enhancing the cargo canvassing effort level may help the forwarder to overcome this dilemma . However with an increasing level of effort there is a mutual inhibition of dual service purchasing and market entry which hurts both the stakeholders profits simultaneously . Interestingly we show that a win win situation exists when the forwarder adopts a dual service purchasing strategy without market entry . Furthermore we verify that this win win situation is Pareto optimized . | Dual service purchasing and market entry problems are investigated. Dual service purchasing benefits the stakeholders. The market entry is a self interest behavior and hurts the forwarder. Mutual inhibition exists under the high effort level of cargo canvassing. Win win strategy and Pareto optimization are identified and interpreted. |
S1366554519309561 | Local and global economies are for many nations highly dependent on the import and export of goods . These goods are shipped through global intermodal freight land water transportation systems that rely on truck rail and maritime networks and their IM terminals . These terminals are crucial to creating and maintaining efficient international trade routes . This paper considers port reliability and resilience as well as the role of ports in supporting a larger resilient maritime system . Specifically stochastic bi level game theoretic optimization models for assessing and improving the resiliency and reliability of the global port network are presented . Proposed models are devised for a set of independent ports with interacting investment problems for competitive but potentially cooperative environments . Uncertainties in traversal times and port throughput capacities are accounted for by adopting a stochastic optimization method using expected or max min functions to simultaneously hedge against the consequences of multiple possible future port related disaster events . Alternative centralized but stochastic formulations are also provided . This stochastic co opetitive methodology and alternative centralized methods fill an important gap in the maritime resiliency literature . | Models for assessing and improving resiliency and reliability of port networks. Stochastic co opetitive formulations as stochastic Nash and Stackelberg games. Accounting for market interactions multiple hazards investments co opetition. Risk averse worst case and risk neutral expected value strategies. Stochastic centralized methods as benchmark. |
S1366554519309664 | This paper investigates green credit manufacture subsidy and sales subsidy modes in a supply chain with a capital constrained green manufacturer and attempts to find the win win subsidy mode . We show that when the bank loan is infinite and the total subsidies of different modes are equal GC can bring the highest returns with respect to green degree market demand social welfare and environmental benefit . However under the finite loan scenario GC is the optimal choice for the government only when the credit line of the manufacturer is relatively high otherwise MS is the optimal subsidy mode . | A green supply chain with capital constrained manufacturer is considered. Green credit manufacture subsidy and sales subsidy are considered. Green operations strategy of supply chain is examined under various subsidy modes. Supply chain performances under various subsidy modes are compared. Useful managerial insights for firms and government are given. |
S1366554519309688 | Some creators in crowdfunding markets have recently employed deceptive advertising to overstate their product quality . We consider a model in which the policy maker would punish such false advertising when detecting it . Using a signaling framework we examine how deceptive advertising influences rational buyers purchase decisions and how the creator signals its quality via advertising as well as price . We show that the high quality creator finds it optimal to use price and advertising jointly to deter low quality creators mimicking behavior . Moreover whether the deceptive advertising occurs in a crowdfunding market depends on the degree of the policy makers regulation . Counterintuitively a stricter regulation on deceptive advertising might not always deter the low quality creator from mimicking . Moreover our results also indicate that allowing a moderate level of deceptive advertising might benefit consumers because the low type creators deceptive claim might motivate the high quality creator to cover more buyers . | Prices play a supporting role in signaling quality and enhances the signaling effect of advertising. The regulation on deceptive advertising influences the informative effect of advertising. The high quality creator could have a higher success rate when its quality is unknown to consumers. The low quality creators deceptive advertising could benefit the consumer surplus and social welfare. |
S1366554519309767 | This paper proposed an IoT based intelligent logistics dispatching system which enables dynamic coordination between customers order picking robots and cloud technology . This system includes three layouts the framework structure of intelligent dispatching platform based on an IoT environment the multi objective optimization model to achieve the efficient dynamic coordination between customers order picking robots and the cloud technology the core two level algorithm which comprises of Dijkstras algorithm and ant colony algorithm that supports the intelligent dispatching operations . This research shows its ability to efficiently coordinate the dispatching operations through IoT technology to enhance customer satisfaction and outperforms the traditional dispatching methodologies . | An IoT based intelligent dispatching to eliminate customers package pick up time. A multi objective model using MAKLINK theory Dijkstras algorithm and ant colony. IoT infrastructure and methodology to make enterprises logistics more intelligent. |
S1366554519309871 | Given economic and environmental benefits closed loop supply chain has been attracting the attention of scholars and governments around the world . Considering dynamic changes and long term development this paper first constructs a dynamic CLSC model inspired by disease transmission model from the perspective of supply chain system . Then considering the characteristics of product quantities over time the performance and the total profits of the system in different situations are analyzed . Finally a numerical study is carried out to analyze the operation condition of the dynamic system by which some additional conclusions are made . | From the systems perspective a dynamic model of closed loop supply chain inspired by disease transmission model is proposed. The optimal solutions to maintain system balance are obtained. The performance of closed loop supply chain system under different product quantity characteristics is analyzed. A numerical experiment is carried out to verify the validity of the model. |
S1366554519309913 | The sensitivity of the pass through ratio of the added costs due to the enforced sulfur emission cap of liner shipping as extra fare for shippers and rail operation frequency on the competitiveness of China Europe railway express and liner shipping for cargo transportation between China and Europe is analyzed . The objective is to lay a theoretical basis for liner companies to optimize the pass through ratio for maximizing shipping profit for CER express to determine an expected operation frequency and for IMO to understand the effects of the enforced sulfur emission cap when CER express is available . | The liner shipping and China Europe Railway express between China and Europe are targeted. The enforced sulfur emission convention of the IMO is taken as the background. The added cost of liner shipping companies due to the adoption of the measures is estimated. Transported commodities between China and Europe are clustered into 9 groups. The effects of the enforced sulfur emission convention on the sulfur and CO. emissions in China Europe freight market are forecasted. |
S1366554519310099 | Forward Freight Agreement is used by shipping market players for hedging . We evaluate the hedging performance of the FFAs by comparing the conventional approach of minimum variance with the quantile regression . The quantile hedge ratios tend to be different from the conventional one indicating the possibility of over or under hedge . Including the error correction term reduces the discrepancy between the quantile hedge ratios and the conventional one . The FFA of one month horizon is more informative to the physical market than other FFAs of longer horizons . Overall the Panamax sector has a better hedging performance than the Capesize one and the quantile hedge should be preferred for the Capesize sector . | Forward Freight Agreement FFA has been used for risk hedging. We use quantile regression to evaluate the hedging performance of FFAs. The conventional approach could render over or under hedge. The FFA of one month horizon is more informative to the physical market. |
S1366554519310130 | By considering different regulations on retailers recycle responsibly we study a dominant retailers collection decision under upstream competition . The equilibrium collection model and effort are derived under different regulations . We find that the lenient regulation in the emerging markets is more likely to induce a socially inefficient equilibrium and the strict regulation in the developed market induces a socially efficient equilibrium . The results suggest that the policymaker should motive the retailer to undertake more collection responsibility when the intensity of upstream competition is not too low . | Analyse dominant retailers incentives of undertaking used products collection in emerging markets with lenient regulation. Study the optimal prices and return effort in reverse supply chain. Examine forward and backward competitions in reverse supply chain. Specify the condition under which policymakers in emerging markets should impose more collection responsibility on retailers. |
S1366554519310233 | A cooperative advertising program is an incentive scheme in which a manufacturer shares its retailers local advertising costs . Such programs have received increasing academic attention in the past two decades . However the local media company as the agent of local advertising has been ignored by previous literature . Another practical aspect being ignored is that the manufacturer only shares the retailers local media advertising cost the retailers in store advertising cost is not subsidized . | We propose the first co op model considering the role of local media company. In co op case the local media company charges the retailer a lower profit rate. The local media company takes co op programs with a differential pricing strategy. With the local media company some results about co op advertising do not hold. |
S1366554519310282 | In this paper we study the effects of introducing competition on supply chain systems and partner collaboration . We find that a system with internal competition obtains greater total profits higher effective CSR investment levels lower sales prices and a larger market share through no collaboration or only CSR investment collaboration than a system without internal competition . Through introducing competition between retailers only CSR investment cooperation achieves the same effective CSR investment level and total profits as CSR investment and pricing joint cooperation . We give some managerial insights into strategies for regional collaboration . | Two systems are discussed to verify the value of introducing internal competition. Three types of collaboration intensity are analyzed and compared. The efficiency of supply chain members CSR investment is taken into decision models. The strategies about CSR investment are proposed to promote regional collaboration. |
S1366554519310324 | This paper proposes different network structures for a real liner shipping company to serve demands between Norwegian and European continental ports . The current practice of the shipping company deploys a feeder network where all routes depart from the European port . We study the impact of using a hub and spoke network that is composed of mother and daughter routes with the possibility of splitting pickups and deliveries . Computational studies carried out on problem instances based on realistic data show that significant cost reductions can in several cases be obtained by including the proposed network structure . | Different network designs are studied for a liner shipping company. A feeder network design connects a major European port to local ports. A hub and spoke design allows transshipments at any local port. Both designs are modeled and solved based on realistic data. A discussion of which network design offering better costs is provided. |
S1366554519310609 | This paper employs the tri variate Markov regime switching copula model to investigate the dynamic dependence between the shipping freight and stock markets . Stronger contemporaneous and bidirectional lead lag relationships between the two markets are detected in the contagion regime which however are weaker in the normal regime . Compared with the Chinese stock market the US stock market can affect and be affected by the shipping freight market in a more sensitive manner . Additionally contagion risk between the two markets increases in most cases due to a decrease in the volume of the US China trade . The results have important implications for market prediction and risk management . | The dynamic tri variate Markov regime switching MRS copula model is applied to examine contagion risk. A vector autoregressive VAR model is used to investigate the impact of the volume of the US China trade. A stronger dependence in the contagion regime is confirmed by the contemporaneous and lead lag relationships. |
S1366554519311081 | To the best of our knowledge this is the first paper to utilise a novel dynamic factor model to investigate the economic relationships between 65 commodity maritime transportation and financial markets under three different frequencies in a single methodological framework . The paper overcomes a limitation of the previous literature that uses pairwise models and as such informational cross market relationships which may have been ignored or not captured are uncovered for the first time . Results indicate strong economic relationships from commodity to freight markets with crude oil prices serving as the leading indicator among all the investigated markets but also between different sub markets . The results are important to international investors and traders but also provide essential insights to policymakers and regulators in terms of commercial strategies asset positioning network supply chain modelling asset investment allocation budgeting and risk management . | First time use of dynamic factor model investigating economic spillover effects. Crude oil prices are the leading economic indicator for commodity and freight rates. Commodities react faster to new market information and transmit it to freight markets. Freight rates react differently to corresponding commodity price movements. Lead lag economic relationships can enhance trading and risk management strategies. |
S1366554519311172 | The cordon based large truck restriction regulation makes large truck based cargo movement process interrupted because large trucks are deterred from moving into some specified areas within given time periods . As a result cargoes carried by a large truck need to be transferred from the large truck to small ones at a freight distribution center for the last few miles . This study aims to analyze the multiple equilibrium behaviors for auto travellers and one freight carrier under the CBLTRR . A link flow based generalized Nash equilibrium model is first developed to characterize mixed routing behaviors of these two types of users . In the model auto travellers follow first Wardropian principle to find their individual shortest paths while the freight carrier minimizes its total freight cost . We then proceed to explore the existence and uniqueness of pure strategy equilibrium and reduction to variational inequality . When the pure strategy equilibrium does not exist or is intractable we propose an approach to construct a mixed equilibrium with restricted action space . The restricted action space is formed based on recurring best responses of two types of users which could reflect their actual interactive decisions of a non cooperative traffic pattern evolution . A solution algorithm is developed to find those equilibriums . The developed models and solution algorithms are evaluated and their potential applications are illustrated through numerical experiments . | Investigate multiple equilibrium behaviors in the context of implementing CBLTRR. Propose a freight demand redistribution mechanism in presence of CBLTRR. Formulate a GNE model to characterize multiple equilibrium behaviors under CBLTRR. Explore multiple equilibrium behaviors with mixed strategy and propose a restricted mixed equilibrium. Propose a heuristic to construct restricted mixed equilibrium. |
S1366554519311202 | This study focuses on the transformation of logistics centers in Industry 4.0 . Aim is to reveal the important criteria for logistics centers in Industry 4.0 by considering link to traditional logistics centers practices and proposing a framework for new logistics centers . Initially literature review to reveal criteria for logistics centers in Industry 4.0 is conducted . Secondly fuzzy multi criteria decision making methodology is used to present the importance order and the causal relationship between criteria to make recommendations for future implications . The results may be useful for logistics centers professionals in transition process and new research topics may be derived for academics . | Focus is on transformation of logistics centers in Industry 4.0. Traditional logistics center operations are linked to Industry 4.0 technologies. Fuzzy DEMATEL is used as methodology. A framework for Logistics Center 4.0 is proposed. |
S136655451931124X | This paper investigates a barge evacuation planning problem that can arise during land reclamation projects . The problem was motivated by the issue faced in actual practice by the Hong Kong International Airport . In this problem a fleet of heterogeneous barges working at an offshore land reclamation site needs to be evacuated to coastal shelters prior to the arrival of a storm . Having no propulsion power of their own these barges must be towed by tug boats in order to be evacuated . The problem under consideration is very complicated since it involves a series of inter correlated assignment and scheduling decisions at different planning levels . To solve the problem this paper first formulates the problem as a nonlinear Mixed Integer Programming model . The model is then linearized . We further proved that the BEPP is NP hard in the strong sense . In view of the complexity of the problem a tailored heuristic method is proposed . Extensive numerical experiments and a case study are performed and the results demonstrate the effectiveness and efficiency of the solution method . Land reclamation projects have become increasingly popular in recent years and the proposed method is applicable to solving BEPPs arising in similar scenarios . | We study the barge evacuation planning problem that arises in real situations. We present a Mixed Integer Programming model for the problem and prove that the problem is strongly NP hard. We propose a tailored heuristic algorithm to solve the problem. Computational experiments show that our proposed method is effective and efficient. |
S1366554519311445 | Consumers are usually uncertain about the product value in the online channel . They may feel disappointed if the outcome is worse than their prior expectation . This paper explores the effect of consumer disappointment aversion on the online sellers decisions about pricing ordering and quick response where the seller can implement either a partial coverage strategy or a full coverage strategy . We identify conditions under which the seller should choose a partial coverage strategy to target only high value consumers . Furthermore we show that disappointment aversion has a significant impact on the employment of quick response . In particular when the degree of disappointment aversion is sufficiently high the seller who implements a no refund policy should not adopt quick response . Finally we find that the effect of consumers disappointment aversion on the sellers profit depends on the latters return policy . If the seller provides no refund to consumers disappointment aversion is always detrimental to the seller . However a seller who provides a full refund to consumers may benefit from disappointment aversion . Particularly it is profitable to adopt a full refund policy when disappointment aversion and salvage value exceed certain thresholds . | The impact of disappointment aversion on quick response of online sellers is examined. Consumers disappointment aversion may have a negative effect on quick response. The seller can benefit from disappointment aversion under a full refund policy. The optimal refund policy depends on disappointment aversion and salvage value. |
S1366554519311457 | We consider a luxury supply chain in which one Stackelberg manufacturer sells products to consumers through a retailer . Driven by exclusivity or conformity consumers are classified as either snobs or conformists with uncertain preferences about the product . The manufacturer can obtain a private signal on this preference while the retailer can not . Results show that the manufacturer makes different market targeting schedules in response to different signals . Interestingly the manufacturer may benefit from either a no information a private information or an information sharing policy depending on its market targeting strategy . Not sharing the manufacturers information however is preferred by the retailer . | Social influence on market targeting strategies for a luxury supply chain is examined. Manufacturer is more informative than retailer on consumers valuation on product. Manufacturers market targeting strategies are examined under asymmetric information. Manufacturer may be worse off by sharing its information with retailer. Private information policy is always preferred by retailer. |
S1366554519311688 | With the rise of cross border e commerce the third party forwarding logistics service becomes increasingly popular . Different from the traditional third party logistics service the 3PFL company provides forwarding services cost effectively by consolidating orders from different e tailers platforms . The random arrivals of orders create a big challenge . Different from most of the existing studies a deep learning based one step integration optimal decision making approach S2SCL is proposed in this paper which intelligently integrates inventory optimization and demand forecasting process . The Seq2Seq based forecasting architecture which integrates CNN and LSTM network is able to model the system dynamics and dependency relations in varying demand for logistics services . Besides generating the point forecasting results the proposed approach can quantify demand uncertainty via a dynamic distribution and make optimal decision on logistics service capacity allocation . Through a case study analysis with real data obtained from a 3PFL company in Chinas Great Bay Area we compare the proposed S2SCL with two benchmark models including a one step statistics based integration approach ARIMA and a two step optimization based approach PSO ELM for two tasks point forecasting and optimal logistic service capacity allocation . Experimental results show that S2SCL outperforms the two benchmark models in both tasks significantly . | Optimize capacity allocation for cross border e commerce related 3PFL operations. Propose a deep learning model for one step intelligent optimal decision making. Quantify demand uncertainty in real time for end to end logistics service demand management. Construct a real case study and illustrate the effectiveness of the proposed approach. |
S1369527420300059 | Bacterial gene regulation occurs through complex networks wherein linear systems respond to intracellular or extracellular cues and engage on vivid crosstalk . The ubiquitous water borne bacterium | small molecule signaling comprises the quorum sensing autoinducer LAI 1 and c di GMP. quorum sensing and c di GMP signaling regulate motility virulence natural competence and biofilm architecture. The pleiotropic transcription factor LvbR links the Lqs system and c di GMP signaling. Nitric oxide exogenously controls the. c di GMP regulatory network. |
S1369527420300060 | Gene duplication facilitates the evolution of biological complexity as one copy of a gene retains its original function while a duplicate copy can acquire mutations that would otherwise diminish fitness . Duplication has played a particularly important role in the evolution of regulatory networks by permitting novel regulatory interactions and responses to stimuli . The diverse MarR family of transcription factors illustrate this concept ranging from highly specific repressors of single operons to pleiotropic global regulators controlling hundreds of genes . MFTFs are often genetically and functionally linked to antimicrobial efflux systems . However the SlyA MFTF lineage in the | MarR family transcription factors MFTFs are ancient regulatory proteins predating the divergence of Archaea and Bacteria. Gene duplication has accommodated the adaptation of MFTFs to multiple regulatory functions. Allosteric inhibition by small aromatic molecules confers MFTF responsiveness to environmental and physiological stimuli. Variation in DNA binding domains and promoters contributes to MFTF specificity. |
S1369527420300096 | Pyrin is an inflammasome sensor in phagocytes that is activated in response to bacterial toxins and effectors that modify RhoA . Pathogen effector triggered pyrin activation is analogous to an indirect guard mechanism in plants . Pyrin activation appears to be triggered when RhoA GTPases in a host cell are prevented from binding downstream signaling proteins . RhoA transducers that control this response include PRK kinases which negatively regulate pyrin by phosphorylation and binding of 14 3 3 proteins . Microtubules regulate pyrin at different levels and may serve as a platform for inflammasome nucleation . Pyrin increases inflammation in the lung gut or systemically during infection or intoxication in mouse models and protects against systemic infection by decreasing bacterial loads . Pathogenic | The pyrin inflammasome is triggered in response to RhoA inactivation. Bacterial effectors and toxins that inactivate RhoA vary in mechanism. Pyrin induced inflammation protects against systemic bacterial infection. Familial Mediterranean Fever is caused by mutations in the pyrin gene. Selective pressure by plague may have driven gain of function. mutations. |
S136952742030014X | Transition metals from manganese to zinc function as catalytic and structural cofactors for an amazing diversity of proteins and enzymes and thus are essential for all forms of life . During infection inflammatory host proteins limit the accessibility of multiple transition metals to invading pathogens in a process termed nutritional immunity . In order to respond to host mediated metal starvation bacteria employ both protein and RNA based mechanisms to sense prevailing transition metal concentrations that collectively regulate systems level strategies to maintain cellular metallostasis . In this review we discuss a number of recent advances in our understanding of how bacteria orchestrate the adaptive response to host mediated multi metal restriction highlighting crosstalk among these regulatory systems . | Maintaining cellular metal bioavailability is a tightly regulated process. Host mediated metal sequestration via calprotectin may result in multi metal restriction. The bacterial response to metal starvation involves intricate regulatory networks. Metal starvation elicits significant crosstalk among metallostasis systems. Overcoming metal ion imbalance involves metabolic remodeling. |
S1369527420300163 | The repertoire of microbial cues monitored by animal and plant tissues encompasses not just molecules but also microbial activities . These include typical pathogen strategies of injuring membranes degrading cellular material and scavenging resources . These activities however are not exclusive to pathogens . Instead they characterize the competitive strategies of microbes living in multispecies communities like those typically found colonizing host tissues . Similar activities are also deployed by host tissues to keep microbes in check . We propose that host surveillance and mimicry of Microbial Associated Competitive Activities derived from an evolutionary history of living in mixed microbial communities has shaped contemporary animal and plant tissue programs of defense repair metabolism and development . | Hosts monitor their resident Microbial Associated Competitive Activities MACAs . MACAs target cellular vulnerabilities common to prokaryotic and eukaryotic cells. Hosts deploy MACA mimics to control resident microbes and invading pathogens. Host sensing of MACAs regulates tissue programs of defense repair and growth. Host sensing of MACA mimics refines programs of tissue defense and development. |
S1369527420300175 | forms single and mixed species biofilms on both tissue and medical devices in the host often under exposure to fluid flow giving rise to infections that are recalcitrant to treatment . The factors that drive enterococcal biofilm formation in the host however remain unclear . Recent reports in other pathogens show how surface sensing by bacteria can trigger the transition from planktonic to sessile lifestyle . Fluid flow can enhance initial adhesion but also influence quorum sensing . Biofilm specific factors as well as biofilm size and extracellular polymeric substances can compromise opsonization and phagocytosis . Bacterial interspecies synergy can create favorable conditions in the host for biofilm formation . Through these concepts we define the knowledge gaps in understanding host associated | Surface sensing in bacteria triggers adaptation to a sessile lifestyle. Fluid flow and tissue topography affect autoinducer levels and quorum sensing. Bifunctional factors in bacteria promote biofilm and compromise opsonization. Inability of neutrophils to phagocytose biofilms triggers NETosis. Polymicrobial interactions influence the pathogenesis of biofilm related infections. |
S1369527420300187 | Chronic infections often contain complex polymicrobial communities that are recalcitrant to antibiotic treatment . The pathogens associated with these infectious communities are often studied in pure culture for their ability to cause disease . However recent studies have begun to focus on the role of polymicrobial interactions in disease outcomes . | Spatial heterogeneity in the lung environment can influence microbial interactions. Context dictates shifts between cooperative and competitive microbial interactions. interacts with bacteria fungi and viruses in infection. The outcome of these interactions can shape disease progression within the host. |
S1369527420300217 | Intestinal helminth parasites present major challenges to the welfare of humans and threaten the global food supply . While the discovery of anthelminthic drugs empowered our ability to offset these harms to society the alarming rise of anthelminthic drug resistance mitigates contemporary efforts to treat and control intestinal helminthic infections . Fortunately emerging research points to potential opportunities to combat anthelminthic drug resistance by harnessing the gut microbiome as a resource for discovering novel therapeutics and informing responsible drug administration . In this review we highlight research that demonstrates this potential and provide rationale to support increased investment in efforts to uncover and translationally utilize knowledge about how the gut microbiome mediates intestinal helminthic infection and its outcomes . | We need new tools to mitigate the harm posed by anthelminthic drug resistance. Evidence links the gut microbiome to helminthic infection and its outcomes. The gut microbiome may mediate infection and define infection sensitivity. Future research should determine if the gut microbiome could encode novel therapeutics or guide infection prevention methods. |
S1369527420300242 | Proteins that regulate transcription often also play an architectural role in the genome . Thus it has been difficult to define with precision the distinctions between transcription factors and nucleoid associated proteins . Anachronistic descriptions of NAPs as histone like implied an organizational function in a bacterial chromatin like complex . Definitions based on protein abundance regulatory mechanisms target gene number or the features of their DNA binding sites are insufficient as marks of distinction and trying to distinguish transcription factors and NAPs based on their ranking within regulatory hierarchies or positions in gene control networks is also unsatisfactory . The terms transcription factor and NAP are | Addresses the nature of the distinction between bacterial transcription factors and nucleoid associated proteins. Proteins lie along a spectrum of influence extending from highly specific to very pervasive effects on gene expression. Uses the BldC protein from. as an example. BldC is compared with Xis the excisionase DNA binding and architectural protein that is expressed by bacteriophage lambda. |
S1369527420300254 | Infections caused by antibiotic resistant bacteria are a major threat to public health . The pathogens causing these infections can acquire antibiotic resistance genes in a process termed horizontal gene transfer . HGT is a common event in the human gut microbiome that is the microbial ecosystem of the human intestinal tract . HGT in the gut microbiome can occur via different mechanisms of which transduction and conjugation have been best characterised . Novel bioinformatic tools and experimental approaches have been developed to determine the association of antibiotic resistance genes with their microbial hosts and to quantify the extent of HGT in the gut microbiome . Insights from studies into HGT in the gut microbiome may lead to the development of novel interventions to minimise the spread of antibiotic resistance genes among commensals and opportunistic pathogens . | The human gut microbiome harbours antibiotic resistance genes the resistome . Antibiotic resistance genes can spread in the gut microbiome through horizontal gene transfer HGT . The best characterised mechanisms of HGT in the human gut microbiome are transduction and conjugation. Novel bioinformatic and experimental approaches have been developed to study HGT in the gut. |
S1369527420300266 | Chronic infections place a significant burden on healthcare systems requiring over 25 billion in treatment annually in the United States alone | Quorum sensing is frequently lost or downregulated in chronic infection. Interactions often lead to increased antibiotic tolerance and disease severity. Spatial organization of microbes in an infection influences their interactions. Polymicrobial interactions have not been demonstrated in most human infections. |
S136952742030028X | is an opportunistic pathogen that normally colonizes the human anterior nares . At the same time this pathogen is one of the leading causes of life threatening bloodstream infections such as sepsis and endocarditis . In this review we will present the current understanding of the pathogenesis of these invasive infections focusing on the mechanisms of | Phagocytes play both protective and detrimental roles in containing bloodstream. hijacks the host coagulation system and uses it to bind host endothelium. Strategies used by. to cause host damage are highly strain dependent. Multiple regulatory systems control. bloodstream infections including Agr ArlRS and MgrA. |
S1369527420300291 | Since the initial discovery of bacterial nucleotide second messengers we have made huge progress towards understanding these complex signalling networks . Many NSM networks contain dozens of metabolic enzymes and binding targets whose activity is tightly controlled at every regulatory level . They function as global regulators and in specific signalling circuits controlling multiple aspects of bacterial behaviour and development . Despite these advances there is much still to discover with current research focussing on the molecular mechanisms of signalling circuits the role of the environment in controlling NSM pathways and attempts to understand signalling at the whole cell community level . Here we examine recent developments in the NSM signalling field and discuss their implications for understanding this important driver of microbial behaviour . | Structural analysis of NSM regulators reveals new mechanisms of NSM signalling. NSM proteins binding multiple ligands support crosstalk between signalling networks. NSM networks control structure and heterogeneity in complex microbial communities. The diversity of bacterial NSM regulators is far higher than previously thought. The p ppApp toxin suggests non signalling roles exist for bacterial NSMs. |
S1369527420300308 | An overarching theme of cellular regulation in bacteria arises from the trade off between growth and stress resilience . In addition the formation of biofilms contributes to stress survival since these dense multicellular aggregates in which cells are embedded in an extracellular matrix of self produced polymers represent a self constructed protective and homeostatic niche . As shown here for the model bacterium | Growth versus maintenance resilience is the overarching theme of cellular regulation. Why transition to multicellularity is integrated into the growth versus survival framework. The large scale architecture of biofilms reflects growth versus survival transitions in 3D space. Sigma factors and transcription factors as the backbone of the regulatory network. Small signaling molecules as dynamic network triggers and drivers. |
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