This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constru...This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constructs a Sino-US container shipping network through voyage weighting and analyzes the essential structural characteristics to explore the network’s complex structural fea-tures.The network’s evolution is examined from three perspectives,namely,time,space,and event influence,aiming to comprehens-ively explore the network’s evolution mechanism.The results revealed that:1)the weighted Sino-US container shipping network exhib-its small-world and scale-free properties.Key hub ports in the United States include NEW YORK NY,SAVANNAH GA,LOS ANGELES CA,and OAKLAND CA,whereas SHANGHAI serving as the hub port in China.The geographical distribution of these hub ports is uneven.2)Concerning the evolution of the weighted Sino-US container shipping network,from a temporal perspective,the evolution of the regional structure of the entire Sino-US region and the Inland United States is in a stage of radiative expansion and de-velopment,with a need for further enhancement in competitiveness and development speed.The evolution of the regional structure of southern China and Europe is transitioning from the stage of radiative expansion and development to an advanced equilibrium stage.The shipping development in Northern China,the Western and Eastern United States,and Asia is undergoing significant changes but faces challenges of fierce competition and imbalances.From a spatial perspective,the rationality and effectiveness of the improved weighted Barrat-Barthelemy-Vespignani(BBV)model are confirmed through theoretical derivation.The applicability of the improved evolution model is verified by simulating the evolution of the weighted Sino-US container shipping network.From an event impact per-spective,the Corona Virus Disease 2019(COVID-19)pandemic has not fundamentally affected the spatial pattern of the weighted Sino-US container shipping network but has significantly impacted the network’s connectivity.The network lacks sufficient resilience and stability in emergency situations.3)Based on the analysis of the structural characteristics and evolution of the weighted Sino-US con-tainer shipping network,recommendations for network development are proposed from three aspects:emphasizing the development of hub ports,focusing on the balanced development of the network,and optimizing the layout of Chinese ports.展开更多
This study analyzes the effect of ship size on the liner service configuration by establishing an economic model. The service configuration is characterized by the distance of service and the number of calling ports. ...This study analyzes the effect of ship size on the liner service configuration by establishing an economic model. The service configuration is characterized by the distance of service and the number of calling ports. A study ease is presented for illustration. At last such a conclusion is drawn that given a fixed profit, the ship size will change with the extension of service in the same direction, while the change rate of ship size is a little higher than that of the extension of service.展开更多
Shipping companies operating liner services keep facing a high level of competition because of the increasing demand for these operators to provide fast, efficient, effective and reliable service. It is challenging fo...Shipping companies operating liner services keep facing a high level of competition because of the increasing demand for these operators to provide fast, efficient, effective and reliable service. It is challenging for these liner operators to offer such services and still be competitive without strategic planning. It, therefore, makes planning and scheduling of shipping routes essential for the smooth operation of liner ships, especially shipping lines operating heterogeneously mixed size fleets. This paper aims to solve a heterogeneously mixed size fleet problem by using an operation research method with the implementation of linear programming to develop optimal shipping routes for a fleet of five vessels serving six coastal ports to get optimal results. An optimal solution to the problem is found with only two routes selected as the optimal shipping routes out of four routes that are considered. The results also showed that a vessel can be assigned to multiple shipping routes.展开更多
As one of the main modes of capacity sharing in the shipping alliance,the essence of which is the space mutual rent transaction among members.However,under the current trading system,the sharing of capacity between sh...As one of the main modes of capacity sharing in the shipping alliance,the essence of which is the space mutual rent transaction among members.However,under the current trading system,the sharing of capacity between shipping enterprises requires a lot of transaction costs and communication costs,cooperation efficiency is not high,and there is a certain competitive relationship between enterprises,they work for their own interests,resulting in more difficult cooperation,and blockchain consensus mechanism,intelligent contracts,distributed bookkeeping and other characteristics can solve these problems of alliance cooperation.Therefore,based on the idea of blockchain,this paper designs a model of mutual lease cooperation in shipping union cabins,gives the model and process of mutual lease transactions based on blockchain,realizes mutual trust and win-win situation among members,simulates through the combination of Hyperledger Fabric and Matlab,and verifies the applicability of blockchain to shipping alliance capacity sharing cooperation.展开更多
Recycled shipping containers have the potential to be successfully used as a net-zero ready home.This study aims to evaluate the outcomes of a high-performance shipping container single-family housing project located ...Recycled shipping containers have the potential to be successfully used as a net-zero ready home.This study aims to evaluate the outcomes of a high-performance shipping container single-family housing project located in Virginia Beach,Virginia.The project was awarded the Best Undergraduate Project in the Single-family division at the 2019 U.S.Department of Energy’s Solar Decathlon Design Challenge.The Hampton University Millennial Village Design Team designed a marketable net-zero ready container home for the ViBe Creative District in Virginia Beach,Virginia.Container Homes are not suitable for every homeowner,but they have a particular appeal to a generation of young and creative people across the country.For many municipalities in Virginia,where container housing is not readily accepted,the ViBe creative district has been having discussions with City code officials and local architects about the benefits.The Hampton University Millennial Village Design Team aimed to take advantage of the competition as an opportunity to explore a building construction method that is not widely seen in this part of the country.Testing design for net-zero readiness is a comprehensive way to understand how this type of construction performs from a building science standpoint.Collaboration with professional industry advisors helped the team to use research-based design methods to work on a unique project that the team believes will become a reality in the future.For the performance assessment of a net-zero container house,several simulation tools were used to investigate the environmental impacts,daylight performance,envelope performance,Energy Use Intensity(EUI),Home Energy Rating System(HERS),and solar energy generation.As for energy standards and codes,the Virginia residential code(VRC)2015,International Energy Conservation Code(IECC)2015 and The American Society of Heating,Refrigerating and Air-Conditioning Engineers(ASHRAE)90.1-2013 for residential buildings were consulted to set each variable for the net-zero container house project.The Rem/Rate energy simulation software achieved the HERS index of 51 and 0 without and with the applications of roof photovoltaics,respectively.展开更多
With the rapid consolidation of global container shipping lines over the past three years,the top three companies’market share has currently climbed to 46%from 26%in 2000,starting to make contribution to easing the p...With the rapid consolidation of global container shipping lines over the past three years,the top three companies’market share has currently climbed to 46%from 26%in 2000,starting to make contribution to easing the pain of overcapacity,improving the network and reducing management cost.However,the industry remains in a highly competitive status if measured by the Herfindahl-Hirschman Index(HHI).展开更多
Improving the cooperative scheduling efficiency of equipment is the key for automated container terminals to copewith the development trend of large-scale ships. In order to improve the solution efficiency of the exis...Improving the cooperative scheduling efficiency of equipment is the key for automated container terminals to copewith the development trend of large-scale ships. In order to improve the solution efficiency of the existing spacetimenetwork (STN) model for the cooperative scheduling problem of yard cranes (YCs) and automated guidedvehicles (AGVs) and extend its application scenarios, two improved STN models are proposed. The flow balanceconstraints in the original model are decomposed, and the trajectory constraints of YCs and AGVs are added toacquire the model STN_A. The coupling constraint in STN_A is updated, and buffer constraints are added toSTN_A so that themodel STN_B is built.As the size of the problem increases, the solution speed of CPLEX becomesthe bottleneck. So a heuristic method containing three groups of heuristic rules is designed to obtain a near-optimalsolution quickly. Experimental results showthat the computation time of STN_A is shortened by 49.47% on averageand the gap is reduced by 1.69% on average compared with the original model. The gap between the solution ofthe heuristic rules and the solution of CPLEX is less than 3.50%, and the solution time of the heuristic rules is onaverage 99.85% less than the solution time of CPLEX. Compared with STN_A, the computation time for solvingSTN_B increases by 58.93% on average.展开更多
In the context of building a country with a strong transportation network,railway container transportation(RCT)is an important means of reducing costs,increasing efficiency,and adjusting transportation structures.Thus...In the context of building a country with a strong transportation network,railway container transportation(RCT)is an important means of reducing costs,increasing efficiency,and adjusting transportation structures.Thus,its impact on regional economic development is important.Based on data from railway container-handling stations and spatial econometric models,this study discusses the differences in the development of RCT and their impact on regional economic development at different leves.This study has three main findings:first,there are significant regional differences in the development of the RCT.The intra-regional differences between the eastern and central regions of China(which do not include Hong Kong,Macao and Taiwan)are gradually narrowing,while the regional differences in the western region are widening.Meanwhile,the intra-regional differences in important economic zones such as Pearl River Delta Economic Zone(PRDEZ),Chengdu-Chongqing Economic Zone(CYEZ),Bohai Rim Economic Zone(BHEZ),and Yangtze River Delta Economic Zone(YRDEZ)are narrowing daily.Second,the development differences of RCT in regional level and important economic regions level show different trends.The unbalanced features of large regions are increasingly evident,whereas the differences in economic regions are decreasing.However,the problem of overlapping RCT remains prominent.Third,the transformation of RCT development mode and fierce competition among transportation modes cause RCT to have a restraining effect on the regional economy at three levels.Rational allocation of resources and other means must be used to guide the transformation from inhibition to promotion,and by formulating targeted policies that will promote the development of RCT,which will improve the transportation structure and help construct a country with a strong transportation system.展开更多
Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation pe...Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation performance of MCT.To solve the practical resource scheduling problem(RSP)in MCT efficiently,this paper has contributions to both the problem model and the algorithm design.Firstly,in the problem model,different from most of the existing studies that only consider scheduling part of the resources in MCT,we propose a unified mathematical model for formulating an integrated RSP.The new integrated RSP model allocates and schedules multiple MCT resources simultaneously by taking the total cost minimization as the objective.Secondly,in the algorithm design,a pre-selection-based ant colony system(PACS)approach is proposed based on graphic structure solution representation and a pre-selection strategy.On the one hand,as the RSP can be formulated as the shortest path problem on the directed complete graph,the graphic structure is proposed to represent the solution encoding to consider multiple constraints and multiple factors of the RSP,which effectively avoids the generation of infeasible solutions.On the other hand,the pre-selection strategy aims to reduce the computational burden of PACS and to fast obtain a higher-quality solution.To evaluate the performance of the proposed novel PACS in solving the new integrated RSP model,a set of test cases with different sizes is conducted.Experimental results and comparisons show the effectiveness and efficiency of the PACS algorithm,which can significantly outperform other state-of-the-art algorithms.展开更多
Container ports and hinterland manufacturing are two important forces of the local participation in economic globalization.This study,taking the Pearl River Delta(PRD),China with an export-oriented economy as an examp...Container ports and hinterland manufacturing are two important forces of the local participation in economic globalization.This study,taking the Pearl River Delta(PRD),China with an export-oriented economy as an example,applies Huff and panel regres-sion models to evaluate the impact of hinterland manufacturing on the development of container ports during the period of 1993–2019.The results show that 1)the spatial patterns of hinterlands for hub ports help to determine the distribution range and scale of economic variables that affect port throughput;2)the hinterland’s gross manufacturing output has universally positive influence on port through-put,wherein export-oriented processing and the entire manufacturing industry have significantly positive impact on port throughput in 1993–2011 and 2001–2019,respectively;3)the two internal structural factors related to an export-oriented economy,labor-intensive sectors and foreign-funded terminals,have positively moderate the direct influence of hinterland manufacturing on port throughput.Our results highlight the importance of local context in understanding port-manufacturing relationship in developing economies.Based on our findings,policy implications are further proposed to enhance port network organization in PRD.展开更多
This study aims to investigate whether Corporate Social Responsibility(CSR)activities reduce supply chain disruptions by examining the impact of the Suez Canal obstruction on the Ever Given container ship in March 202...This study aims to investigate whether Corporate Social Responsibility(CSR)activities reduce supply chain disruptions by examining the impact of the Suez Canal obstruction on the Ever Given container ship in March 2021.This study conclude that the more responsible companies have higher returns and are less affected by this event than the less responsible companies;the less responsible companies have lower returns.The companies with better CSR have a lower impact on their supply chains when faced with disruptions in the supply chain.展开更多
The most prominent risk assessment techniques are founded on the values of measuring and controlling the frequency and the consequences of risks in order to assure an“acceptable level”of“safeness”mainly in the lin...The most prominent risk assessment techniques are founded on the values of measuring and controlling the frequency and the consequences of risks in order to assure an“acceptable level”of“safeness”mainly in the lines of environmental,health and hygiene and port product issues.This paper examines security risk assessment approaches within the emerging role of ports.This paper contributes to the current literature by considering the ports of Greece as a case in point and by measuring the degree of its security risk orientation based on certain valid risk factors drawn from the current literature.Moreover,it presents a security risk assessment methodology into the domain of port container terminals.Their potential for ports were quantitatively and qualitatively assessed by discussing issues of security approaches within the maritime industry,in order to facilitate improvement strategies.A two-dimension empirical study was conducted,in a time range of ten years(2010-2020)in order to provide evidence regarding security risk assessment in the port container terminal of Thessaloniki,in Greece.The findings of this study have significant strategic policy implications and shed more light on the role of security risks in the overall risk orientation of container terminals in practice.Finally,further research directions in security risk in ports are proposed.展开更多
[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, r...[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, riversand, sludge were taken as media of hardwood cutting and survival rate, seedling height were taken as indexes to select media for container seedling of triploid clones of Populus tomentosa. [Result] Different mixedmedia had great influence on survival rates of container seedlings. Taking peat and vermiculite with the proportion of 5∶2 (M10) or peat ,vermiculite with the proportion of 7∶2 (M11) or sandy loam (M1) as media would generate higher cutting survival rate that was higher than 90.0%. There were significant differece in height increments of container seedlings. Taking sandy loam, peat and vermiculite with the proportion of 6∶2∶2(M5)or sandy loam (M1), seedling height of 60-days the seedling was over 37.0 cm. [Conclusion] According to cost analysis of nursery medium, the optimum medium for hardwood cuttings container seedling-raising of triploid clones of Populus tomentosa was sandy loam.展开更多
In order to improve the survival rate of planting seedlings of Phoebe zhen-nan, the grading standard for one-year-old container seedlings of Phoebe zhennan was developed by using cluster analysis. The results showed t...In order to improve the survival rate of planting seedlings of Phoebe zhen-nan, the grading standard for one-year-old container seedlings of Phoebe zhennan was developed by using cluster analysis. The results showed that the quality of Phoebe zhennan container seedlings could be estimated from seedling height and ground diameter. The Phoebe zhennan container seedlings were divided into 3 grades: Grade 1 (seedling height ≥ 38 cm; ground diameter ≥ 0.65 cm), Grade 2 (31.7 cm ≤ seedling height 〈 38 cm; 0.56 cm ≤ ground diameter 〈 0.65 cm) and Grade 3 (seedling height 〈 31.7 cm; ground diameter 〈 0.56 cm).展开更多
The similarities and differences between the container terminal logistics system(CTLS)and the Harvard-architecture computer system are compared in terms of organization and architecture.The mapping relation and the mo...The similarities and differences between the container terminal logistics system(CTLS)and the Harvard-architecture computer system are compared in terms of organization and architecture.The mapping relation and the modeling framework of the CTLS are presented based on multi-agent,and the successful algorithms in the computer domain are applied to the modeling framework,such as the dynamic priority and multilevel feedback scheduling algorithm.In addition,a model and simulation on a certain quay at Shanghai harbor is built up on the AnyLogic platform to support the decision-making of terminal on service cost.It validates the feasibility and creditability of the above systematic methodology.展开更多
[Objective] This study aimed to investigate the optimal component of culti- vation medium for container seedling raising of Camellia oleifera. [Method] In the application of container nursery technology of Camellia ol...[Objective] This study aimed to investigate the optimal component of culti- vation medium for container seedling raising of Camellia oleifera. [Method] In the application of container nursery technology of Camellia oleifera grafting in emergent stocks, yellow clay soil, surface soil of pine forest, decomposed edible fungus, peat soil, dung and dirt were mixed by different proportions into five formulae as nursery substrates, with garden soil as the control, in order to investigate the influences of various substrates on the growth of annual Camellia oleifera container seedlings by using randomized block design based on variance analysis and multiple comparisons, and to screen the optimal substrate formula for container nursery of Camellia oleifera. [Result] The influences of different substrates on the transplanting survival rate, seedling height, basal diameter, height-diameter ratio and lateral root length of Camellia oleifera container seedlings were significantly different. Various growth indi- cators of Camellia oleifera container seedlings cultivated in the substrate containing 40% of yellow clay soil + 15% of surface soil of pine forest + 20% of decomposed edible fungus + 20% of peat soil + 5% of dung and dirt exceeded that of the control and other substrate formulae, which could be used as the optimal substrate formula for the container nursery of Camellia oleifera. [Conclusion] This study screened the optimal substrate formula for the container nursery of Camellia oleifera, which provided technical reference for the cultivation of Camellia oleifera container seedlings.展开更多
The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the bloo...The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly understood.The major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier function.It plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier,in addition to the transport of lipids,such as docosahexaenoic acid,across the blood-brain barrier.Furthermore,an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases;however,little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain barrier.This paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier,including their basic structures and functions,cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier,and the in-depth studies on lipid transport and the regulation of blood-brain barrier permeability.This comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to date.This will not only help to elucidate the pathogenesis of neurological diseases,improve the accuracy of laboratory diagnosis,and optimize clinical treatment strategies,but it may also play an important role in prognostic monitoring.In addition,the effects of major facilitator superfamily domain containing 2A on blood-brain barrier leakage in various diseases and the research progress on cross-blood-brain barrier drug delivery are summarized.This review may contribute to the development of new approaches for the treatment of neurological diseases.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.41201473,41371975)。
文摘This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constructs a Sino-US container shipping network through voyage weighting and analyzes the essential structural characteristics to explore the network’s complex structural fea-tures.The network’s evolution is examined from three perspectives,namely,time,space,and event influence,aiming to comprehens-ively explore the network’s evolution mechanism.The results revealed that:1)the weighted Sino-US container shipping network exhib-its small-world and scale-free properties.Key hub ports in the United States include NEW YORK NY,SAVANNAH GA,LOS ANGELES CA,and OAKLAND CA,whereas SHANGHAI serving as the hub port in China.The geographical distribution of these hub ports is uneven.2)Concerning the evolution of the weighted Sino-US container shipping network,from a temporal perspective,the evolution of the regional structure of the entire Sino-US region and the Inland United States is in a stage of radiative expansion and de-velopment,with a need for further enhancement in competitiveness and development speed.The evolution of the regional structure of southern China and Europe is transitioning from the stage of radiative expansion and development to an advanced equilibrium stage.The shipping development in Northern China,the Western and Eastern United States,and Asia is undergoing significant changes but faces challenges of fierce competition and imbalances.From a spatial perspective,the rationality and effectiveness of the improved weighted Barrat-Barthelemy-Vespignani(BBV)model are confirmed through theoretical derivation.The applicability of the improved evolution model is verified by simulating the evolution of the weighted Sino-US container shipping network.From an event impact per-spective,the Corona Virus Disease 2019(COVID-19)pandemic has not fundamentally affected the spatial pattern of the weighted Sino-US container shipping network but has significantly impacted the network’s connectivity.The network lacks sufficient resilience and stability in emergency situations.3)Based on the analysis of the structural characteristics and evolution of the weighted Sino-US con-tainer shipping network,recommendations for network development are proposed from three aspects:emphasizing the development of hub ports,focusing on the balanced development of the network,and optimizing the layout of Chinese ports.
基金The National Natural Science Foundation of China (40635026)
文摘This study analyzes the effect of ship size on the liner service configuration by establishing an economic model. The service configuration is characterized by the distance of service and the number of calling ports. A study ease is presented for illustration. At last such a conclusion is drawn that given a fixed profit, the ship size will change with the extension of service in the same direction, while the change rate of ship size is a little higher than that of the extension of service.
文摘Shipping companies operating liner services keep facing a high level of competition because of the increasing demand for these operators to provide fast, efficient, effective and reliable service. It is challenging for these liner operators to offer such services and still be competitive without strategic planning. It, therefore, makes planning and scheduling of shipping routes essential for the smooth operation of liner ships, especially shipping lines operating heterogeneously mixed size fleets. This paper aims to solve a heterogeneously mixed size fleet problem by using an operation research method with the implementation of linear programming to develop optimal shipping routes for a fleet of five vessels serving six coastal ports to get optimal results. An optimal solution to the problem is found with only two routes selected as the optimal shipping routes out of four routes that are considered. The results also showed that a vessel can be assigned to multiple shipping routes.
文摘As one of the main modes of capacity sharing in the shipping alliance,the essence of which is the space mutual rent transaction among members.However,under the current trading system,the sharing of capacity between shipping enterprises requires a lot of transaction costs and communication costs,cooperation efficiency is not high,and there is a certain competitive relationship between enterprises,they work for their own interests,resulting in more difficult cooperation,and blockchain consensus mechanism,intelligent contracts,distributed bookkeeping and other characteristics can solve these problems of alliance cooperation.Therefore,based on the idea of blockchain,this paper designs a model of mutual lease cooperation in shipping union cabins,gives the model and process of mutual lease transactions based on blockchain,realizes mutual trust and win-win situation among members,simulates through the combination of Hyperledger Fabric and Matlab,and verifies the applicability of blockchain to shipping alliance capacity sharing cooperation.
文摘Recycled shipping containers have the potential to be successfully used as a net-zero ready home.This study aims to evaluate the outcomes of a high-performance shipping container single-family housing project located in Virginia Beach,Virginia.The project was awarded the Best Undergraduate Project in the Single-family division at the 2019 U.S.Department of Energy’s Solar Decathlon Design Challenge.The Hampton University Millennial Village Design Team designed a marketable net-zero ready container home for the ViBe Creative District in Virginia Beach,Virginia.Container Homes are not suitable for every homeowner,but they have a particular appeal to a generation of young and creative people across the country.For many municipalities in Virginia,where container housing is not readily accepted,the ViBe creative district has been having discussions with City code officials and local architects about the benefits.The Hampton University Millennial Village Design Team aimed to take advantage of the competition as an opportunity to explore a building construction method that is not widely seen in this part of the country.Testing design for net-zero readiness is a comprehensive way to understand how this type of construction performs from a building science standpoint.Collaboration with professional industry advisors helped the team to use research-based design methods to work on a unique project that the team believes will become a reality in the future.For the performance assessment of a net-zero container house,several simulation tools were used to investigate the environmental impacts,daylight performance,envelope performance,Energy Use Intensity(EUI),Home Energy Rating System(HERS),and solar energy generation.As for energy standards and codes,the Virginia residential code(VRC)2015,International Energy Conservation Code(IECC)2015 and The American Society of Heating,Refrigerating and Air-Conditioning Engineers(ASHRAE)90.1-2013 for residential buildings were consulted to set each variable for the net-zero container house project.The Rem/Rate energy simulation software achieved the HERS index of 51 and 0 without and with the applications of roof photovoltaics,respectively.
文摘With the rapid consolidation of global container shipping lines over the past three years,the top three companies’market share has currently climbed to 46%from 26%in 2000,starting to make contribution to easing the pain of overcapacity,improving the network and reducing management cost.However,the industry remains in a highly competitive status if measured by the Herfindahl-Hirschman Index(HHI).
基金National Natural Science Foundation of China(62073212).
文摘Improving the cooperative scheduling efficiency of equipment is the key for automated container terminals to copewith the development trend of large-scale ships. In order to improve the solution efficiency of the existing spacetimenetwork (STN) model for the cooperative scheduling problem of yard cranes (YCs) and automated guidedvehicles (AGVs) and extend its application scenarios, two improved STN models are proposed. The flow balanceconstraints in the original model are decomposed, and the trajectory constraints of YCs and AGVs are added toacquire the model STN_A. The coupling constraint in STN_A is updated, and buffer constraints are added toSTN_A so that themodel STN_B is built.As the size of the problem increases, the solution speed of CPLEX becomesthe bottleneck. So a heuristic method containing three groups of heuristic rules is designed to obtain a near-optimalsolution quickly. Experimental results showthat the computation time of STN_A is shortened by 49.47% on averageand the gap is reduced by 1.69% on average compared with the original model. The gap between the solution ofthe heuristic rules and the solution of CPLEX is less than 3.50%, and the solution time of the heuristic rules is onaverage 99.85% less than the solution time of CPLEX. Compared with STN_A, the computation time for solvingSTN_B increases by 58.93% on average.
基金Under the auspices of National Key Research and Development Program of China(No.2023YFB4302200)National Natural Science Foundation of China(No.71831002,72174053)+1 种基金Liaoning Province Xingliao Talent Plan(No.XLYC2008030)Talent Planning in Dalian(No.2022RG05)。
文摘In the context of building a country with a strong transportation network,railway container transportation(RCT)is an important means of reducing costs,increasing efficiency,and adjusting transportation structures.Thus,its impact on regional economic development is important.Based on data from railway container-handling stations and spatial econometric models,this study discusses the differences in the development of RCT and their impact on regional economic development at different leves.This study has three main findings:first,there are significant regional differences in the development of the RCT.The intra-regional differences between the eastern and central regions of China(which do not include Hong Kong,Macao and Taiwan)are gradually narrowing,while the regional differences in the western region are widening.Meanwhile,the intra-regional differences in important economic zones such as Pearl River Delta Economic Zone(PRDEZ),Chengdu-Chongqing Economic Zone(CYEZ),Bohai Rim Economic Zone(BHEZ),and Yangtze River Delta Economic Zone(YRDEZ)are narrowing daily.Second,the development differences of RCT in regional level and important economic regions level show different trends.The unbalanced features of large regions are increasingly evident,whereas the differences in economic regions are decreasing.However,the problem of overlapping RCT remains prominent.Third,the transformation of RCT development mode and fierce competition among transportation modes cause RCT to have a restraining effect on the regional economy at three levels.Rational allocation of resources and other means must be used to guide the transformation from inhibition to promotion,and by formulating targeted policies that will promote the development of RCT,which will improve the transportation structure and help construct a country with a strong transportation system.
基金This research was supported in part by the National Key Research and Development Program of China under Grant 2022YFB3305303in part by the National Natural Science Foundations of China(NSFC)under Grant 62106055+1 种基金in part by the Guangdong Natural Science Foundation under Grant 2022A1515011825in part by the Guangzhou Science and Technology Planning Project under Grants 2023A04J0388 and 2023A03J0662.
文摘Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation performance of MCT.To solve the practical resource scheduling problem(RSP)in MCT efficiently,this paper has contributions to both the problem model and the algorithm design.Firstly,in the problem model,different from most of the existing studies that only consider scheduling part of the resources in MCT,we propose a unified mathematical model for formulating an integrated RSP.The new integrated RSP model allocates and schedules multiple MCT resources simultaneously by taking the total cost minimization as the objective.Secondly,in the algorithm design,a pre-selection-based ant colony system(PACS)approach is proposed based on graphic structure solution representation and a pre-selection strategy.On the one hand,as the RSP can be formulated as the shortest path problem on the directed complete graph,the graphic structure is proposed to represent the solution encoding to consider multiple constraints and multiple factors of the RSP,which effectively avoids the generation of infeasible solutions.On the other hand,the pre-selection strategy aims to reduce the computational burden of PACS and to fast obtain a higher-quality solution.To evaluate the performance of the proposed novel PACS in solving the new integrated RSP model,a set of test cases with different sizes is conducted.Experimental results and comparisons show the effectiveness and efficiency of the PACS algorithm,which can significantly outperform other state-of-the-art algorithms.
基金Under the auspices of the National Natural Science Foundation of China(No.41930646)Guangdong Natural Science Foundation(No.2022A1515011572)。
文摘Container ports and hinterland manufacturing are two important forces of the local participation in economic globalization.This study,taking the Pearl River Delta(PRD),China with an export-oriented economy as an example,applies Huff and panel regres-sion models to evaluate the impact of hinterland manufacturing on the development of container ports during the period of 1993–2019.The results show that 1)the spatial patterns of hinterlands for hub ports help to determine the distribution range and scale of economic variables that affect port throughput;2)the hinterland’s gross manufacturing output has universally positive influence on port through-put,wherein export-oriented processing and the entire manufacturing industry have significantly positive impact on port throughput in 1993–2011 and 2001–2019,respectively;3)the two internal structural factors related to an export-oriented economy,labor-intensive sectors and foreign-funded terminals,have positively moderate the direct influence of hinterland manufacturing on port throughput.Our results highlight the importance of local context in understanding port-manufacturing relationship in developing economies.Based on our findings,policy implications are further proposed to enhance port network organization in PRD.
文摘This study aims to investigate whether Corporate Social Responsibility(CSR)activities reduce supply chain disruptions by examining the impact of the Suez Canal obstruction on the Ever Given container ship in March 2021.This study conclude that the more responsible companies have higher returns and are less affected by this event than the less responsible companies;the less responsible companies have lower returns.The companies with better CSR have a lower impact on their supply chains when faced with disruptions in the supply chain.
文摘The most prominent risk assessment techniques are founded on the values of measuring and controlling the frequency and the consequences of risks in order to assure an“acceptable level”of“safeness”mainly in the lines of environmental,health and hygiene and port product issues.This paper examines security risk assessment approaches within the emerging role of ports.This paper contributes to the current literature by considering the ports of Greece as a case in point and by measuring the degree of its security risk orientation based on certain valid risk factors drawn from the current literature.Moreover,it presents a security risk assessment methodology into the domain of port container terminals.Their potential for ports were quantitatively and qualitatively assessed by discussing issues of security approaches within the maritime industry,in order to facilitate improvement strategies.A two-dimension empirical study was conducted,in a time range of ten years(2010-2020)in order to provide evidence regarding security risk assessment in the port container terminal of Thessaloniki,in Greece.The findings of this study have significant strategic policy implications and shed more light on the role of security risks in the overall risk orientation of container terminals in practice.Finally,further research directions in security risk in ports are proposed.
基金Supported by National Key Technology R&D Program during the 11th Five-year Plan Period(2006BAD32B01)~~
文摘[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, riversand, sludge were taken as media of hardwood cutting and survival rate, seedling height were taken as indexes to select media for container seedling of triploid clones of Populus tomentosa. [Result] Different mixedmedia had great influence on survival rates of container seedlings. Taking peat and vermiculite with the proportion of 5∶2 (M10) or peat ,vermiculite with the proportion of 7∶2 (M11) or sandy loam (M1) as media would generate higher cutting survival rate that was higher than 90.0%. There were significant differece in height increments of container seedlings. Taking sandy loam, peat and vermiculite with the proportion of 6∶2∶2(M5)or sandy loam (M1), seedling height of 60-days the seedling was over 37.0 cm. [Conclusion] According to cost analysis of nursery medium, the optimum medium for hardwood cuttings container seedling-raising of triploid clones of Populus tomentosa was sandy loam.
基金Supported by Forestry Science and Technology Program of Hunan Province(2010-06)~~
文摘In order to improve the survival rate of planting seedlings of Phoebe zhen-nan, the grading standard for one-year-old container seedlings of Phoebe zhennan was developed by using cluster analysis. The results showed that the quality of Phoebe zhennan container seedlings could be estimated from seedling height and ground diameter. The Phoebe zhennan container seedlings were divided into 3 grades: Grade 1 (seedling height ≥ 38 cm; ground diameter ≥ 0.65 cm), Grade 2 (31.7 cm ≤ seedling height 〈 38 cm; 0.56 cm ≤ ground diameter 〈 0.65 cm) and Grade 3 (seedling height 〈 31.7 cm; ground diameter 〈 0.56 cm).
基金The National Key Technology R&D Program of China during the 11th Five-Year Plan Period(No.2006BAH02A06)
文摘The similarities and differences between the container terminal logistics system(CTLS)and the Harvard-architecture computer system are compared in terms of organization and architecture.The mapping relation and the modeling framework of the CTLS are presented based on multi-agent,and the successful algorithms in the computer domain are applied to the modeling framework,such as the dynamic priority and multilevel feedback scheduling algorithm.In addition,a model and simulation on a certain quay at Shanghai harbor is built up on the AnyLogic platform to support the decision-making of terminal on service cost.It validates the feasibility and creditability of the above systematic methodology.
基金Supported by Natural Science Foundation of Hubei Province(2012FFC03101)~~
文摘[Objective] This study aimed to investigate the optimal component of culti- vation medium for container seedling raising of Camellia oleifera. [Method] In the application of container nursery technology of Camellia oleifera grafting in emergent stocks, yellow clay soil, surface soil of pine forest, decomposed edible fungus, peat soil, dung and dirt were mixed by different proportions into five formulae as nursery substrates, with garden soil as the control, in order to investigate the influences of various substrates on the growth of annual Camellia oleifera container seedlings by using randomized block design based on variance analysis and multiple comparisons, and to screen the optimal substrate formula for container nursery of Camellia oleifera. [Result] The influences of different substrates on the transplanting survival rate, seedling height, basal diameter, height-diameter ratio and lateral root length of Camellia oleifera container seedlings were significantly different. Various growth indi- cators of Camellia oleifera container seedlings cultivated in the substrate containing 40% of yellow clay soil + 15% of surface soil of pine forest + 20% of decomposed edible fungus + 20% of peat soil + 5% of dung and dirt exceeded that of the control and other substrate formulae, which could be used as the optimal substrate formula for the container nursery of Camellia oleifera. [Conclusion] This study screened the optimal substrate formula for the container nursery of Camellia oleifera, which provided technical reference for the cultivation of Camellia oleifera container seedlings.
基金supported by the National Natural Science Foundation of China,No.82104412(to TD)Shaanxi Provincial Key R&D Program,No.2023-YBSF-165(to TD)+1 种基金the Natural Science Foundation of Shaanxi Department of Science and Technology,No.2018JM7022(to FM)Shaanxi Provincial Key Industry Chain Project,No.2021ZDLSF04-11(to PW)。
文摘The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly understood.The major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier function.It plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier,in addition to the transport of lipids,such as docosahexaenoic acid,across the blood-brain barrier.Furthermore,an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases;however,little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain barrier.This paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier,including their basic structures and functions,cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier,and the in-depth studies on lipid transport and the regulation of blood-brain barrier permeability.This comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to date.This will not only help to elucidate the pathogenesis of neurological diseases,improve the accuracy of laboratory diagnosis,and optimize clinical treatment strategies,but it may also play an important role in prognostic monitoring.In addition,the effects of major facilitator superfamily domain containing 2A on blood-brain barrier leakage in various diseases and the research progress on cross-blood-brain barrier drug delivery are summarized.This review may contribute to the development of new approaches for the treatment of neurological diseases.