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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Analysis and Scheduling of machinery in an Intermodal Terminal by using the OSPF Concept

Khan, Osama Adnan Ghaffari January 2008 (has links)
The design of an Internet Protocol (IP) network is a long-term investment where many aspects must be taken into consideration. Some of them are the cost of the design, network sustainability and aspects regarding traffic engineering. When, its matter to design an IP network for an industry like Sea ports or Container Terminal than the factors related to traffic engineering and scheduling needs more attention. This thesis addresses the problems of designing and suggests a solution with IP network by using the concept of Open Shortest Path First (OSPF) routing algorithm. The routing in OSPF telecommunication networks is determined by computing shortest paths with respect to link weights sets by the network operator. In this research the shortest path computed on the basis of Current status, Current location, distance and cargo limitation of Automated Guided Vehicles that are using cassettes to transfer containers, which are called C-AGVs. A MATLAB based simulation tool is developed and is used to test and compare the OSPF algorithm to the general scheduling processes in a container terminal. The results show that using the OSPF concept it will yield in higher productivity. / osamaadnan79@hotmail.com + 46 737879001
12

A Multi Agent Web Based Simulation Model for Evaluating Container Terminal Management

Bakht, Syed Sikandar, Ahmad, Qazi Sohail January 2006 (has links)
This thesis provides a software prototype of Container Terminal Management system with the help of a Multi Agent systems technology. The goal that has been tried to achieve during this research work was to solve the management issues residing in a CT. The software prototype can be implemented as simulation software that will help the Terminal Managers to take necessary decisions for the better productivity of CT. The CTs are struggling with taking proper management decisions. There are many policies implemented but the use of a certain policy at a proper time is the main issue. It is possible with simulation software to visualize the affects of decisions taken by the implementation of a policy and see the expected output. This can really improve the performance of a CT. The management decision problem is solved by modeling the whole CT in a computer modeling language. The prototype shows all the actors appearing in a CT in the form of Agents and these agents are responsible for carrying out certain tasks. The prototype is the final contribution along with partial implementation. The model is proposed to be a web based system which removes the platform dependability problem and provide availability online. / Qazi Sohail Ahmad: qazisohail101@gmaili.com Syed Sikandar Bakht: sikandarbakht101@gmail.com
13

A Multi Agent Web Based Simulation Model for Evaluating Container Terminal Management

Bakht, Syed Sikandar, Ahmad, Qazi Sohail January 2008 (has links)
This thesis provides a software prototype of Container Terminal Management system with the help of a Multi Agent systems technology. The goal that has been tried to achieve during this research work was to solve the management issues residing in a CT. The software prototype can be implemented as simulation software that will help the Terminal Managers to take necessary decisions for the better productivity of CT. The CTs are struggling with taking proper management decisions. There are many policies implemented but the use of a certain policy at a proper time is the main issue. It is possible with simulation software to visualize the affects of decisions taken by the implementation of a policy and see the expected output. This can really improve the performance of a CT. The management decision problem is solved by modeling the whole CT in a computer modeling language. The prototype shows all the actors appearing in a CT in the form of Agents and these agents are responsible for carrying out certain tasks. The prototype is the final contribution along with partial implementation. The model is proposed to be a web based system which removes the platform dependability problem and provide availability online.
14

A Multi-agent Based Model for Inter Terminal Transportation

Iqbal, Mubashir January 2015 (has links)
Context: Due to an increase in inter-terminal transportation (ITT) volume within a container port; complexity of transportation processes between the terminals has also increased. Problems with the current way of handling ITT resources are expected to rise in the near future. Different types of vehicles are already in place for transporting containers between different terminals in a container port. However, there need to be an efficient and effective use of these vehicle types in order to get maximum benefits out of these resources. Objectives: In this thesis, we investigate and propose a solution model for ITT considering the combination of both manned (MTS, Trucks) and unmanned (AGV) vehicles. An agent based model is proposed for ITT focusing on three ITT vehicle types. Objective of proposed model is to investigate the capabilities and combination of different vehicles for transporting containers between different container terminals in a port.  Methods: A systematic literature review is conducted to identify the problems and methods and approaches for solving those problems in the domain of container transportation. As a case, an agent-based model is proposed for the Maasvlakte area of the Rotterdam port. Simulations are performed on different scenarios to compare three different road vehicle types, i.e., AGV, MTS, and truck, in a network comprising of ten terminals. Results: Literature review results indicate that heuristics is the most commonly used method to solve different problems of container transportation in the recent past. The review also depicts that limited research has been published focusing on ITT when compared to intra-terminal transportation. Simulation results of our proposed model indicate that AGVs outperforms trucks in terms of loading/unloading time and number of vehicles required to handle the given volume of all scenarios. In most of the cases, it is observed that the number of trucks required are twice as much as compared to AGVs in order to transport containers between different terminals. Results also show that lower number MTS vehicles (as compared to AGVs) are required for handling containers in certain scenarios; however, the loading/unloading time for MTS is much higher than that of AGVs. Conclusions: Using agent-based simulation experiments, we propose a model that can help in estimating the required resources (vehicles) to handle the ITT containers volume and improve the utilization of different resources in a network of terminals. From comparison of three road vehicle types, it was concluded that trucks are incapable to handle higher container volume in an ITT. It was also concluded that AGVs can be an appropriate choice if automated operations are supported in the terminals, otherwise MTS is the best choice concerning the number of vehicles required to handle containers. Our simulation results may help the ITT planners in better estimations and planning of ITT to meet current and future challenges of transporting high containers volume.
15

Gestion multi-agents d'un terminal à conteneurs / Agent-based modeling of a container terminal

Abourraja, Mohamed Nezar 09 February 2018 (has links)
De nos jours, les plateformes portuaires cherchent à massifier leurs capacités de projection de conteneurs vers et à partir de leurs réseaux hinterland en misant sur les modes ferroviaires et fluviaux. Cela pour évacuer plus rapidement un volume quasi croissant de conteneurs livré par voie maritime et d’éviter les situations indésirables, tels que les situations d'asphyxie. De plus, les plateformes portuaires ont pris conscience que leur attractivité aux yeux des prestataires logistiques dépend non seulement de leur fiabilité et de leurs qualités nautiques mais également de leur capacité à offrir une desserte massifiée de leur hinterland. Contrairement à ce qui a pu être observé en Europe, la part du transport massifié a quasiment stagné au Havre dans les dernières années. A cet effet, le port du Havre a mis en place un terminal multimodal de conteneurs lié par rail et par voie navigable à un hinterland riche et dense en population (Bassin parisien, Marchés européens), et par des navettes ferroviaires aux autres terminaux maritimes du port Havre. L’intérêt économique et stratégique de ce nouveau terminal est de renforcer la position du Grand Port Maritime du Havre au niveau national, européen et mondial, et d’un point de vue écologique, diminuer l’utilisation excessive du routier en misant sur les modes moins polluants. Dans cette thèse, les efforts se focalisent sur la modélisation et la simulation du déroulement des opérations de manutention et d’allocation de ressources dans un terminal à conteneurs et particulièrement l’ordonnancement des portiques de manutention. Étant donné qu’un terminal à conteneurs est un système complexe, nous avons d’abord défini une démarche de modélisation qui facilite le processus de construction du modèle de simulation. Cette démarche est un processus itératif permettant de raffiner le modèle au fur et à mesure des étapes de développement réalisées. Les différentes étapes de développement sont liées par une série de diagrammes qui permet d’exprimer de façon claire les éléments et les relations formant le modèle de simulation. Ensuite, nous avons intégré dans notre modèle deux stratégies de non-croisement de portiques au niveau de la cour ferroviaire du terminal multimodal. Le but de ces stratégies est la minimisation des temps et des mouvements improductifs pour améliorer la performance et la productivité des portiques de manutention. La première stratégie est basée sur des règles de mouvement et sur la collaboration et coopération entre agents portiques. Tandis que la deuxième stratégie est basée sur une heuristique. Ces deux solutions ont été testées en utilisant l’outil de simulation AnyLogic et les résultats obtenus montrent la qualité de nos solutions. Concernant le problème d’ordonnancement des portiques de la cour fluviale, nous l’avons étudié en utilisant un couplage Optimisation-Simulation. Dans ce problème les temps de chargement et de déchargement de conteneurs et les temps de déplacement des portiques entre les baies sont considérés comme incertains. Le couplage est composé d’une méta-heuristique colonie de fourmis et d’un modèle de simulation à base d’agents. Chaque solution (une séquence de tâches) trouvée par l’algorithme d'optimisation est simulée et évaluée pour déterminer les nouvelles durées des tâches qui seront ensuite injectées comme données d’entrée de l’algorithme avant l’itération suivante. / Nowadays, seaports seek to achieve a better massification share of their hinterland transport by promoting rail and river connections in order to more rapidly evacuate increasing container traffic shipped by sea and to avoid landside congestion. Furthermore, the attractiveness of a seaport to shipping enterprises depends not only on its reliability and nautical qualities but also on its massified hinterland connection capacity. Contrary to what has been observed in Europe, the massification share of Le Havre seaport has stagnated in recent years. To overcome this situation, Le Havre Port Authority is putting into service a multimodal hub terminal. This terminal is linked only with massified modes to a rich and dense geographical regions (Ile de France, Lyon), and with rail shuttles to the maritime terminals of Le Havre seaport. The aim of this new terminal is to restrict the intensive use of roads and to provide a river connection to its maritime terminals (MTs) that do not include a river connection from the beginning. In this study, we focus on the modeling and the simulation of container terminal operations (planning, scheduling, handling …) and particularly crane scheduling in operating areas. Designing multi-agents based simulation models for the operation management of a complex and dynamic system is often a laborious and tedious task, which requires the definition of a modeling approach in order to simplify the design process. In this way, we defined a top-down approach with several steps of specification, conception, implementation and verification-validation. This approach is an iterative process that allows the model to become more complex and more detailed. In this thesis, we pay more attention to crane scheduling problem in operating areas. For the rail-rail transshipment yard of the multimodal terminal, we designed two anti-collision strategies that aim to minimize unproductive times and moves to improve crane productivity and to speed up freight train processing. These strategies are tested using multi-method simulation software (Anylogic) and the simulation results reveal that our solutions are very satisfactory and outperform other existing solutions. With regard the fluvial yard, the stochastic version of crane scheduling problem is studied. The problem is solved with a mixed Optimization-Simulation approach, where the loading and unloading times of containers and travel times of cranes between bays are considered uncertain. The used approach is composed of an Ant Colony Optimization (ACO) metaheuristic coupled to an agent-based simulation model. Each solution (a tasks sequence) found by the optimization algorithm is simulated and evaluated to determine the new tasks’ periods which will then be injected as input to the ACO algorithm before the next iteration. The coupling is executed until the difference between the last iterations is too low.
16

A Simulation Modelling Approach for Analysing Logistics Processes in the port of Gävle

Mahmoud, Mohi Eddin, Victor, Andersson January 2019 (has links)
In industries, successful logistics management delivers higher performance and value (time, cost, profits, and quality). Projects involving ports logistics systems are complex to manage due to the level and number of entities to manage, such as the expensive equipment units and the interconnection of the flows of goods and information. In these complex projects, it is difficult to conduct experiments on the real logistics system to help management predict future strategies due to high costs, time and infrastructure constrains. Therefore, to achieve the objectives of managing ports logistics system it requires that managers select the best strategic tools and methods. Simulation is one of the best predictive and strategic tools which allows the use of real-time, real-world data collection to stage mathematical analyses of the “what-if” scenarios. This thesis presents a simulation model for a case study on the port container terminal transportation of the port of Gävle in Sweden. In this model, a simulation approach is developed with a high software engineering maintainability that enables companies to analyse and study various scenarios that are motivated by changes in different inputs to measure their impact on the outputs that include throughput, resource utilization and waiting times. This study method adopted a simulation that covered both qualitative and quantitative research approaches. The main contributions of this study are: (i) developing a simulation program helps improve visibility in decision making process at port industry.(ii) providing a guideline for designing the maintainability of simulation models (iii) The simulation model has proved to be an industrial solution for the case company and its various stakeholders.
17

Development and evaluation of dispatching strategies for the IPSI™ AGV system

Persson, Olof, Kosowski, Patrik January 2006 (has links)
Container Terminals are experiencing increased pressure to raise their productivity levels and capacity, in order to handle the increasing amounts of container cargo due to globalization. Due to space restrictions and other financial factors, automated solutions have been developed. AGVs (Automated Guided Vehicles) are one of those automated solutions for the horizontal transportation with in a Container Terminal. A recent European sponsored project has lead to the development of a new generation of AGVs that are using cassettes namely IPSI™ AGVs. An agent-based simulator has been developed with the purpose of constructing and evaluating dispatching strategies for this new developed AGV system. Already explored dispatching strategies [9, 14] are used with additional modifications to re-evaluate them with the consideration of the usage of cassettes. Our findings from the simulation experiment are suggesting that a cost estimation based approach is much more suited than an inventory based. In addition to that, the results are very convincing in that the number of cassettes used is the most dominate factor despite dispatching strategy for obtaining a fast ship turnaround time.
18

Evaluating Layouts for Automated Transport System using Simulation Approach

Rashid, Rizwan, Kaleem, Babur January 2009 (has links)
Industries such as trade, manufacturing and transportation have undergone significant changes due to the globalization concept. Sea ports play a very important role in building and strengthening the economies of countries worldwide. Due to the high rate of production, the work load has increased at the ports which resulted into financial as well as capacity problems. As a result of such problems, cost optimized and automated solutions are being developed and introduced at the ports. In the horizontal transport system of the sea ports, AGVs are one of those automated solutions used to transport containers from ships to yard and vice versa. Newer and more practices are being employed to make the efficient transportation of these AGVs. Numexia has recently introduced a new version of Cassette AGVs called Zero-Emission C-AGV. A conceptual model is developed for Zero-Emission C-AGVs and different layouts are evaluated using multi agent-based simulation. The greedy algorithm has been used for the efficient dispatching of jobs. The Simulation will carry out the dispatching of jobs for C-AGVs between quay area and yard using different layouts and scenarios for the unloading operation.
19

A dry port as an expansion option for the Cape Town container terminal

De Wet, Christiaan Johannes 04 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Currently maritime ports, including the Port of Cape Town, experience congestion, pollution and other logistics-related problems due to increasing levels of container traffic. The presence of these problems has caused port planners, port operators and logistics firms to look for new solutions in this transport sector. The dry port concept, whereby offloaded containers are stored outside the maritime port in a dedicated logistics area, is recognized as a means for solving some of these major problems, thereby promoting economic development and logistics integration as well as reducing the demand on limited capacity (land and access) at the maritime port. Therefore, the core objective of this study is to demonstrate that the implementation of the dry port concept is a feasible alternative for expanding the throughput capacity of the Cape Town Container Terminal. The Port of Cape Town is strategically one of the best placed ports in South Africa as it is positioned at the South Western extremity of the continent of Africa, thereby linking America and Europe with Asia, the Far East and Australia. Furthermore, the Port of Cape Town also forms a direct link between international trade and about three (3) million consumers in the Western Cape. The recent expansion of the Cape Town Container Terminal was a major investment which included the upgrading of equipment and the expansion of workable surface area, thereby increasing the container terminal yard capacity to 1.4million TEU (TEU = Twenty foot Equivalent Unit) per annum. However, this report showed that the abovementioned increase in volumes as well as the resulting congestion continues to be a challenge at the Port of Cape Town. Firstly, the predicted future container volumes show that the demand in the Port of Cape Town could reach between 1.9 million and 3.2 million TEU per annum by 2039. Secondly, the evaluation of the operational and infrastructural characteristics of the existing Cape Town Container Terminal demonstrated that container terminal yard (CY) area is the capacity limiting characteristic of the terminal and that the operational and infrastructural limits could be reached between 2018 and 2026. The two main functions of a dry port in the Western Cape transportation network would be international trade processing and congestion relief, which are achieved through the duplication and supplementation of the Cape Town Container Terminal facilities at an inland location. The dry port would allow the Western Cape supply chain to absorb any future container volume demands that exceed the CY capacity of the Port of Cape Town and could potentially attract an annual throughput of 0.7 million TEU by 2039. Furthermore, the facility could address the problem of congestion in and around the greater Cape Town metropolitan, resulting in an improved transportation network that will have a positive effect on passenger traffic, productivity of trucks, competitiveness of the Port of Cape Town as well as the environmental sustainability of the transportation system. The dry port concept would therefore be appealing to Transnet Port Authority / Transnet Port Terminals, Shippers and Logistics Managers and the Western Cape Regional Community. The site selection analysis performed in this study evaluated three possible dry port locations, namely: Kraaifontein Area, Ysterplaat Air Force Base and Bellville Precinct. Although the analysis identified that all three of the sites have the potential to be developed into a successful dry port; however, that the Bellville Precinct is the preferred location due to the presence of the Belcon freight rail facility. The success of such a facility will greatly depend on the project’s ability to ensure that the resources needed for the initial investment is kept to a minimum, and ultimately the most viable dry port solution in the Western Cape region would be the phased development of Bellville Precinct. From this it is clear that a dry port could be a feasible alternative for expanding the throughput capacity of the Port of Cape Town, as well as improving the transport infrastructure in the Cape Town area. / AFRIKAANSE OPSOMMING: Maritieme hawens, insluitende die Kaapstadse hawe, ondervinding tans opeenhoping, besoedeling en ander logistieke probleme as gevolg van toenemende vlakke van die houer verkeer. Die teenwoordigheid van hierdie probleme het veroorsaak dat hawe beplanners, hawe-operateurs en logistiek maatskappye op soek is vir nuwe oplossings in die vervoer sektor. Die droë hawe konsep word erken as 'n middel vir die oplossing van sommige van hierdie probleme, en sodoende ekonomiese ontwikkeling en logistieke integrasie te bevorder, sowel as die verlaging van aanvraag op beperkte kapasiteit (grond en toegang) by die maritieme hawe. Daarom is die kern doel van hierdie studie om aan te toon dat die implementering van die droë hawe konsep 'n haalbare alternatief is vir die uitbreiding van die deurset kapasiteit van die Kaapstadse Houerterminaal. Die Kaapstadse hawe is strategies een van die bes geplaaste hawens in Suid-Afrika, want dit is geleë aan die suid-westerlikste punt van Afrika en verbind Amerika en Europa met Asië, die Verre Ooste en Australië. Verder vorm die Kaapstadse hawe ook 'n direkte skakel tussen die buitelandse markte en die drie (3) miljoen verbruikers in die Wes-Kaap. Die onlangse uitbreiding van die Kaapstadse Houerterminaal het die stoorkapasiteit van die terminaal aansienlik verbeter an 1.4 miljoen TEU per jaar, deur middel van die opgradering van toerusting en die uitbreiding van werkbare oppervlak. Hierdie verslag bewys egter dat die bogenoemde toename in volumes sowel as die gevolglike opeenhoping steeds teenwoordig is in die Kaapstadse hawe. Eerstens, die voorspelde toekomstige houervolumes toon dat die aanvraag in die Kaapstadse hawe tussen 1.9 miljoen en 3.2 miljoen TEU's per jaar kan bereik teen 2039. Tweedens, die evaluering van die operasionele en infrastrukturele kenmerke van die bestaande Kaapstadse Houerterminaal het getoon dat die houer stoorarea die kapasiteit beperkende kenmerk van die terminaal is en dat die operasionele en infrastrukturele perke moontlik tussen 2018 en 2026 bereik kan word. Die twee hoof funksies van 'n droë hawe in die Wes-Kaap vervoer netwerk sal internasionale handel verwerking en opeenhoping verligting wees. Hierdie funksies sal bereik word deur die duplisering en aanvulling van die Kaapstadse Houerterminaal fasiliteite by 'n binnelandse perseel. Die droë hawe sal toelaat dat die Wes-Kaap verskaffersiklus enige toekomstige houervolumes, wat meer is as die houer stoorarea kapasiteit van die Kaapstadse hawe, te kan hanteer en kan potensieel 'n jaarlikse deurset van 0.7 miljoen TEU hanteer. Verder kan die
20

Přidaná hodnota kombinované dopravy a její překážky v dalším rozvoji / Added value of combined transport and the barriers in the further development

Dvořáková, Eva January 2011 (has links)
The work is focused on combined transport in the Czech Republic and abroad. The theoretical part contains basic information about combined transport, as well as the combined transport in the CR, the most important terminals and information on individual subjects in combined transport. The work discusses the different development of combined transport both at home and in Germany. The next section discussed the problem of international combined transport and of course the positive aspects of its use. Conclusion of the theoretical part contains trend of combined transport and impact of the financial crisis. The practical part contains model calculation of the return on investment to swap bodies and demonstate the benefits of investment.

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