8,542 research outputs found

    The cost of being landlocked : logistics costs and supply chain reliability

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    A large proportion of the least developed countries are landlocked and their access to world markets depends on the availability of a trade corridor and transit systems. Based on empirical evidence from World Bank projects and assessments in Africa, Central Asia, and elsewhere, this paper proposes a microeconomic quantitative description of logistics costs. The paper theoretically and empirically highlights that landlocked economies are primarily affected not only by a high cost of freight services but also by the high degree of unpredictability in transportation time. The main sources of costs are not only physical constraints but widespread rent activities and severe flaws in the implementation of the transit systems, which prevent the emergence of reliable logistics services. The business and donor community should push toward implementation of comprehensive facilitation strategies, primarily at the national level, and the design of robust and resilient transport and transit regimes. A better understanding of the political economy of transit and a review of the implementation successes and failures in this area are needed.Transport Economics Policy&Planning,Transport and Trade Logistics,Common Carriers Industry,Economic Theory&Research,Rural Roads&Transport

    The Impact of Automated Storage and Retrieval Systems on Warehouse Operations

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    Ocean container transport : an underestimated and critical link in global supply chain performance

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    With supply chains distributed across global markets, ocean container transport now is a critical element of any such supply chain. We identify key characteristics of ocean container transport from a supply chain perspective. We find that unlike continental (road) transport, service offerings tend to be consolidated in few service providers, and a strong focus exists on maximization of capital intensive resources. Based on the characteristics of the ocean container transport supply chain, we list a number of highly relevant and challenging research areas and associated questions

    공컨테이너관리 기법을 활용한 효율적인 컨테이너 공급망

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    학위논문 (박사) -- 서울대학교 대학원 : 공과대학 산업공학과, 2021. 2. 문일경.Due to a remarkable surge in global trade volumes led by maritime transportation, shipping companies should make a great effort in managing their container flows especially in case of carrier-owned containers. To do so, they comprehensively implement empty container management strategies and accelerate the flows in a cost- and time-efficient manner to minimize total relevant costs while serving the maximal level of customers demands. However, many critical issues in container flows universally exist due to high uncertainty in reality and hinder the establishment of an efficient container supply chain. In this dissertation, we fully discuss such issues and provide mathematical models along with specific solution procedures. Three types of container supply chain are presented in the following: (i) a two-way four-echelon container supply chain; (ii) a laden and empty container supply chain under decentralized and centralized policies; (iii) a reliable container supply chain under disruption. These models explicitly deal with high risks embedded in a container supply chain and their computational experiments offer underlying managerial insights for the management in shipping companies. For (i), we study empty container management strategy in a two-way four-echelon container supply chain for bilateral trade between two countries. The strategy reduces high maritime transportation costs and long delivery times due to transshipment. The impact of direct shipping is investigated to determine the number of empty containers to be repositioned among selected ports, number of leased containers, and route selection to satisfy the demands for empty and laden containers for exporters and importers in two regions. A hybrid solution procedure based on accelerated particle swarm optimization and heuristic is presented, and corresponding results are compared. For (ii), we introduce the laden and empty container supply chain model based on three scenarios that differ with regard to tardiness in the return of empty containers and the decision process for the imposition of fees with the goal of determining optimal devanning times. The effectiveness of each type of policy - centralized versus decentralized - is determined through computational experiments that produce key performance measures including the on-time return ratio. Useful managerial insights on the implementation of these polices are derived from the results of sensitivity analyses and comparative studies. For (iii), we develop a reliability model based on container network flow while also taking into account expected transportation costs, including street-turn and empty container repositioning costs, in case of arc- and node-failures. Sensitivity analyses were conducted to analyze the impact of disruption on container supply chain networks, and a benchmark model was used to determine disruption costs. More importantly, some managerial insights on how to establish and maintain a reliable container network flow are also provided.해상 수송이 주도함으로써 전 세계 무역량이 급증하기 때문에 회사 소유 컨테이너는 컨테이너 흐름을 관리하는 데 많은 노력을 기울여야 한다. 이를 위해 공 컨테이너 관리 전략을 포괄적으로 구현하고 효율적인 수송 비용 및 시간 절감 방식으로 컨테이너 흐름을 원활히 하여 관련 총비용을 최소화하는 동시에 고객의 수요를 최대한 충족하게 된다. 그러나 현실에서는 높은 불확실성 때문에 컨테이너 흐름에 대한 많은 주요한 이슈가 보편적으로 존재하고 효율적인 컨테이너 공급망 구축을 방해한다. 본 논문에서는 이러한 이슈에 대해 전반적으로 논의하고 적절한 해법과 함께 수리 모형을 제공한다. 이를 위해 세 가지 유형의 컨테이너 공급망을 다룬다. 먼저 (i) 양방향 네 단계 컨테이너 공급망, (ii) 분권화 및 중앙 집중화 정책에 따른 적∙공 컨테이너 공급망; 그리고 (iii) disruption 상황 속에서 신뢰성을 고려하는 컨테이너 공급망이다. 본 논문에서 제시한 세 가지 모형은 컨테이너 공급망에 내재 된 높은 위험을 직접 다루며 계산 실험은 해운 회사의 경영진이나 관계자를 위해 주요한 관리 인사이트를 제공한다. (i)의 경우, 두 지역 간 양자 무역을 위한 양방향 네 단계 컨테이너 공급망에서 공 컨테이너 관리 전략을 연구한다. 이 전략은 환적으로 인한 높은 해상 운송 비용과 긴 배송 시간을 줄일 수 있다. 또한, 직항 수송의 영향을 조사하여 선택된 항구 중 재배치 할 공 컨테이너 수, 임대 컨테이너 수, 두 지역의 수출업자와 수입업자의 적∙공 컨테이너 대한 수요를 만족하기 위한 경로 선택을 결정하게 된다. APSO 및 휴리스틱을 기반으로 하는 하이브리드 해법을 제시하며 비교 실험을 하였다. (ii)의 경우 최적 devanning time 결정을 목표로 공 컨테이너의 반환 지연과 해당 수수료 부과 결정 프로세스와 관련하여 서로 다른 세 가지 시나리오를 기반으로 적∙공 컨테이너 공급망 모형을 제시한다. 각 유형의 정책적(분권화 및 중앙 집중화) 효과는 정시 반환율을 포함한 주요 성능 측정을 고려하는 계산 실험을 통해 결정된다. 이러한 정책 실행에 대한 유용한 관리 인사이트는 민감도 분석 및 비교 연구의 결과에서 도출한다. (iii)의 경우, 본 논문은 컨테이너 네트워크 흐름을 기반으로 하는 신뢰성 모형을 개발하는 동시에 아크 및 노드 failure가 있을 때 street-turn 및 공 컨테이너 재배치 비용을 포함한 기대 총 비용을 구한다. 중단이 컨테이너 공급망 네트워크에 미치는 영향을 분석하기 위해 민감도 분석을 수행했으며 disruption 비용을 결정하기 위해 벤치마크 모형을 활용한다. 더불어 신뢰성을 고려한 컨테이너 네트워크 흐름을 구축하고 신뢰성을 유지하는 방법에 대한 관리적 인사이트도 제공한다.Abstract i Contents ii List of Tables vi List of Figures viii 1. Introduction 1 1.1 Empty Container Repositioning Problem 1 1.2 Reliability Problem 3 1.3 Research Motivation and Contributions 4 1.4 Outline of the Dissertation 7 2. Two-Way Four-Echelon Container Supply Chain 8 2.1 Problem Description and Literature Review 8 2.2 Mathematical Model for the TFESC 15 2.2.1 Overview and Assumptions 15 2.2.2 Notation and Formulation 19 2.3 Solution Procedure for the TFESC 25 2.3.1 Pseudo-Function-based Optimization Problem 25 2.3.2 Objective Function Evaluation 28 2.3.3 Heuristics for Reducing the Number of Leased Containers 32 2.3.4 Accelerated Particle Swarm Optimization 34 2.4 Computational Experiments 37 2.4.1 Heuristic Performances 39 2.4.2 Senstivity Analysis of Varying Periods 42 2.4.3 Senstivity Analysis of Varying Number of Echelons 45 2.5 Summary 48 3. Laden and Empty Container Supply Chain under Decentralized and Centralized Policies 50 3.1 Problem Description and Literature Review 50 3.2 Scenario-based Model for the LESC-DC 57 3.3 Model Development for the LESC-DC 61 3.3.1 Centralized Policy 65 3.3.2 Decentralized Policies (Policies I and II) 67 3.4 Computational Experiments 70 3.4.1 Numerical Exmpale 70 3.4.2 Sensitivity Analysis of Varying Degree of Risk in Container Return 72 3.4.3 Sensitivity Analysis of Increasing L_0 74 3.4.4 Sensitivity Analysis of Increasing t_r 76 3.4.5 Sensitivity Analysis of Decreasing es and Increasing e_f 77 3.4.6 Sensitivity Analysis of Discounting 〖pn〗_{f1} and 〖pn〗_{f2} 78 3.4.7 Sensitivity Analysis of Different Container Fleet Sizes 79 3.5 Managerial Insights 81 3.6 Summary 83 4. Reliable Container Supply Chain under Disruption 84 4.1 Problem Description and Literature Review 84 4.2 Mathematical Model for the RCNF 90 4.3 Reliability Model under Disruption 95 4.3.1 Designing the Patterns of q and s 95 4.3.2 Objective Function for the RCNF Model 98 4.4 Computational Experiments 103 4.4.1 Sensitivity Analysis of Expected Failure Costs 106 4.4.2 Sensitivity Analysis of Different Network Structures 109 4.4.3 Sensitivity Analysis of Demand-Supply Variation 112 4.4.4 Managerial Insights 115 4.5 Summary 116 5. Conclusions and Future Research 117 Appendices 120 A Proof of Proposition 3.1 121 B Proof of Proposition 3.2 124 C Proof of Proposition 3.3 126 D Sensitivity Analyses for Results 129 E Data for Sensitivity Analyses 142 Bibliography 146 국문초록 157 감사의 글 160Docto

    Automated Transfer Management Systems and the Intermodal Performance of North American Freight Distribution

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    For capacity, energy and environmental reasons, intermodal transportation is widely regarded as the preferable option for inland freight distribution. But because of the relatively high embedded costs, intermodal rail is currently only an attractive option for containerized goods carried over long distances. Transfers that in theory should entail only a few operations at a terminal in reality require multiple operations. This paper argues that by incorporating new terminal designs and an automated transfer management system (ATMS) at terminals and distribution centers, the resulting efficiency advances and productivity gains could significantly improve the economics for both long and short haul intermodal movements, including port shuttle trains. This system not only could significantly lower fixed costs and make intermodal more price competitive, but improve time and reliability to make intermodal more service competitive as well

    Satisficing Strategy in Development of a Port System: Viet Nam Case Study

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    The role of Viet Nam port system increases in simultaneously with its economic development. Although it has had attention and investment from the government since 1990s, it has been still facing with some problems such as congestion in ports and unbalance among ports, and meeting limitations such as geographic conditions, budgets and technologies. Actually, development of a national economy in generally and that of port system in particularly are influenced by many factors and affected mutually. Obviously, the transportation and port systems significantly affect on economy, so they should be paid much attention. Consequently, an overview of ASEAN, Indochina and particular Viet Nam economies is presented, which shows why Viet Nam should be focused on developing its port system. Recently, Viet Nam as well as ASEAN trade has been grown up so remarkably. As a result, Viet Nam transportation demands have been and will be increased, particularly on the maritime transport. Due to Viet Nam geography, port system has been considered as a vital aspect of national transport infrastructure in generally and most important one of maritime transport in particularly. Consequently, a classification of Viet Nam ports would give a deep look on inside aspect and container ports would be mentioned as one of the key project in the future. Actually, port system is a dynamic subject and government policies for development have been updated continuously. A strategic master plan to develop Viet Nam port system until 2010 and targets to 2040, which was issued in 1999, and then up-to-dated master plan issued in 2009 would be reviewed. It would show changes of Viet Nam port system on many aspects such as demands, capacities, and policies. Correspondingly, the transportation planning process would be introduced, which incorporates analysis of business and input from the business community. Consequently, the satisficing strategy for port development would be defined and the reasons why it should be applied for Viet Nam port development would be presented. Sequent theories of interested strategies would be reviewed, which have been applied in many successful port systems in the world. They promise to bring much contribution when making a plan for development of Viet Nam port system. Obviously, many gravitational forces have impacts on Viet Nam port system, which force Viet Nam ports have to change, evolve or die. Responsively, the master plan has been modified to meet up-to-dated requirements. City ports especially in Ho Chi Minh City should be relocated outside to suitable location(s). In addition, strategies to enhance them should be studied and implemented, in which container ports should be paid much attention. Development of Dry Port system, transshipment ports and/or logistics activity zones such as ZALs, Distriparks and/or FTZz is considered as efficient and effective alternatives. Furthermore, other successful and interested strategies applying in developing port systems in the world should be studied and implemented for Viet Nam port system. And also Viet Nam should cooperate with other partners or countries such as the Republic of Korea, which have developed port systems, to get experience, technology, management system, and budget from them. This research would propose some alternatives in development of Viet Nam ports as a satisficing strategy. Obviously, it could not mention all aspects of Vietnamese ports, but it hopes giving useful ideas or alternatives to enhance and develop an effective, efficient and competitive not only for Viet Nam case but also for other developing countries.CHAPTER 1. INTRODUCTION 1 1.1 Roles of transportation and particular port systems in economy 1 1.2 An overview of Viet Nam economy and port systems 4 1.3 Review of strategies to develop port systems 11 1.4 Research Aims and Objectives 13 1.5 Scale and scope 14 1.6 Outlines of the dissertation 14 CHAPTER 2. PROSPECT OF VIET NAM PORT SYSTEM 15 2.1 Viet Nam and ASEAN trade 15 2.2 Classification of Viet Nam ports 25 2.3 Container port system 29 2.4 Strategic master plan 33 2.5 Analysis 38 2.6 Conclusion 41 CHAPTER 3. METHODOLOGIES 42 3.1 Satisficing strategy 43 3.2 Quick evaluation of port systems 50 3.3 Containerization and transshipment ports 60 3.4 Dry port system 65 3.5 ZALs, Distriparks, FTZs and FAZs. 70 3.6 Other strategies 77 3.7 Conclusions 82 CHAPTER 4. SATISFICING STRATEGY IN DEVELOPMENT OF VIET NAM ... 84 4.1 Impacts of economic development on port system and the ... 84 4.2 Enhancement of container ports 99 4.3 Dry port system 109 4.4 ZALs, Distriparks, and FTZs 120 4.5 Consideration of other strategies 129 4.6 Co-operation strategy in maritime industry: Viet Nam &#8211Korea ... 136 4.7 Conclusions 147 CHAPTER 5. CONCLUSIONS AND SUGGESTIONS 148 5.1 Conclusions 148 5.2 Suggestions 149 5.3 Future research 150 REFERENCES 15

    Studying the selection of ports on liner routes

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    The Viability of the Air Mobility Command Pure Pallet Program for US Army Reparable Retrograde Shipments

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    Last year, Congress approved 17.1billiondollars,anincreaseof17.1 billion dollars, an increase of 4 billion dollars more than originally was requested by the Bush Administration, for US Army vehicles to be repaired or replaced (commonly referred to as reset) as a result of military operations in Iraq and Afghanistan. A large portion of the repair workload falls upon the Army depots in Anniston and Red River in Texarkana, Texas and must rely on the DOD transportation system for air and surface movement of retrograde cargo deemed serviceable and unserviceable to fill requisitions and backorders for entry into the national supply inventory. Headquarters Air Mobility Command developed an initiative for distribution to the US Central Command to allow supply requisition shipments to accumulate based on customer defined delivery timelines to a single unit destination to eliminate the need of mixed destinations on a single pallet, thereby avoiding intermediate handling and increase in-transit visibility. This research viewed the depot and the item managers as the customers due to the value they collectively add in equipment repairs and how retrograde is directed to meet the needs of the end user. Subject matter experts from Army Materiel Command provided their inputs through a series of focused interviews to calculate their value placed on transportation system and convergence with a cost comparison of the accumulation principles of the AMC pure pallet program. The results indicated that the AMC pure pallet program was not a viable option due to conflicts with customer requirements, high variability in the volume of retrograde generated to successfully utilize this option despite the savings in using consolidated shipments

    Simulation model for optimization of a landside harbor logistic chain of container terminals.

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    The world wide transportation of all kind of goods with containers is a fast growing business. The challenge is to transport in the shortest time to the lowest cost. The vessels therefore become bigger and bigger. The biggest vessel with 16000 TEU is since December 2012 in service. But the next generation with 18000-22000 TEU is already being built. This raises questions in acceleration of loading and unloading process, the handling in the yards of the harbors and the transportation of the containers to Hinterland. The most common way is still to transport the container from the yard by truck, which causes a lot of traffic jams and pollution. With the growth of the volume and the limited space in most harbours the throughput in the yards must be dramatically increased. One possibility is to reduce multiple handling of the containers and to decentralize the transport to Hinterland. The idea of Dryports emerged several years ago. In this research a simulation model of all processes in the logistic chain is designed, with which all steps are linked together. A direct flow of the containers without any intermediate stocking in the yard. Todays average staytime of the containers in the yard of 3-4 days is completely deleted. The multiple handling is avoided. The variability of all input figures and constraints allows that the most real situations can be considered. Three different modalsplits are run in simulation. The results show, that it is possible to reduce the throughput time of the containers and the overall loading and unloading process of vessels in the harbor and to gain a high productivity. With the satellite model ( Dryport ) it is possible to reduce traffic in the yard and to avoid a lot of pollution. Overall shorter service times give an answer to the challenge of managing the future growth of the container business. The feasibility of the proposed model is confirmed
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