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Algoritmy pro automatizovanou logistiku / Algorithms for automated logisticsTuláček, Michal January 2014 (has links)
This thesis deals with a real world problem of an optimal planning of transferring goods between stores of a certain retail company. The aim is to propose a system which, based on customer orders and current stock items availability, should be capable of devising an optimal plan. In this thesis, following a thorough analysis of the problem, there is a formalised problem of automated logistics. After a brief overview of existing approaches in the area of logistics problem solving, there are subsequently designed solution methods based on programming with limited conditions and mixed integer programming. Both methods are compared to each other experimentally, by taking into account the quality of the found solution and the methods' efficiency.
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Strategic Planning Models and Approaches to Improve Distribution Planning in the Industrial Gas IndustryFarrokhvar, Leily 04 May 2016 (has links)
The industrial gas industry represents a multi-billion dollar global market and provides essential product to manufacturing and service organizations that drive the global economy. In this dissertation, we focus on improving distribution efficiency in the industrial gas industry by addressing the strategic level problem of bulk tank allocation (BTA) while considering the effects of important operational issues. The BTA problem determines the preferred size of bulk tanks to assign to customer sites to minimize recurring gas distribution costs and initial tank installation costs. The BTA problem has a unique structure which includes a resource allocation problem and an underlying vehicle routing problem with split deliveries.
In this dissertation, we provide an exact solution approach that solves the BTA problem to optimality and recommends tank allocations, provides a set of delivery routes, and determines delivery amounts to customers on each delivery route within reasonable computational time. The exact solution approach is based on a branch-and-price algorithm that solves problem instances with up to 40 customers in reasonable computational time.
Due to the complexity of the problem and the size of industry representative problems, the solution approaches published in the literature rely on heuristics that require a set of potential routes as input. In this research, we investigate and compare three alternative route generation algorithms using data sets from an industry partner. When comparing the routes generation algorithms, a sweep-based heuristic was the preferred heuristic for the data sets evaluated.
The existing BTA solution approaches in the literature also assume a single bulk tank can be allocated at each customer site. While this assumption is valid for some customers due to space limitations, other customer sites may have the capability to accommodate multiple tanks. We propose two alternative mathematical models to explore the possibility and potential benefits of allocating multiple tanks at designated customer site that have the capacity to accommodate more than one tank. In a case study with 20 customers, allowing multiple tank allocation yield 13% reduction in total costs.
In practice, industrial gas customer demands frequently vary by time period. Thus, it is important to allocate tanks to effectively accommodate time varying demand. Therefore, we develop a bulk tank allocation model for time varying demand (BTATVD) which captures changing demands by period for each customer. Adding this time dimension increases complexity. Therefore, we present three decomposition-based solution approaches. In the first two approaches, the problem is decomposed and a restricted master problem is solved. For the third approach, a two phase periodically restricting heuristic approach is developed. We evaluate the solution approaches using data sets provided by an industrial partner and solve the problem instances with up to 200 customers. The results yield approximately 10% in total savings and 20% in distribution cost savings over a 7 year time horizon.
The results of this research provide effective approaches to address a variety of distribution issues faced by the industrial gas industry. The case study results demonstrate the potential improvements for distribution efficiency. / Ph. D.
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Strategic supply chain management using simulationVon Raubenheimer, Albert Ludwich 01 December 2005 (has links)
In today's global economy the need for an efficient and optimised supply chain is increasing. Recent studies showed that supply chain management is one of the areas that have a great impact on the financial well being of an organization as well as customer satisfaction. The recognition of the importance of efficient and optimised supply chains has led to increasing investments in supply chain planning and execution systems. In order to compete in the global market place organizations want to develop systems that enable fast and effective on time delivery of products to customers. Therefore generating the necessary customer satisfaction. Today there are APS (Advanced Planning&Scheduling) systems available to help "manage" the supply chains. These tools were specifically designed to have the ability to rapidly and simultaneously plan and schedule customer demand while considering material and capacity constraints. Not only does these systems provide the ability to increase revenues, but it can also increase the customer service and cut costs by synchronized management of the complete supply chain. Although these systems help to improve the system, it is restricted to the static part and it does not incorporate the dynamic part. The result therefore is that a lot of "noise" still exists within the system once the results are achieved. This opened the way for solutions that can provide insight to the uncertainty and interdependency of processes and customer demand within the supply chain. One way of gaining insight into the system variation and interdependencies is through the use of simulation technology. This type of technology allows organizations to predict future behaviour and test future designs or do redesigns of their current supply chains. The scope of this dissertation is to develop a supply chain planning methodology, which will help to improve the understanding of the uncertainty and interdependency of processes within the supply chain. To design this methodology different steps are taken in order to introduce the final solution. Therefore, four main methods were used; literature research, market research, supply chain planning methodology development and a case study. The literature research brought to light the reasons for the inefficiencies and variations in supply chain planning and why the need for change exists. During the supply chain market research several supply chain planning and execution systems were under study. From this it was quite clear that the only way that organisations can ensure one optimal answer is when the demand is constant and there is a zero percent chance that it could change. In real world systems it is virtually impossible to accurately predict future demand 100 percent of the time, and therefore variability and randomness cannot be excluded from a supply chain solution. This paved the way for the introduction of simulation technology as a possible solution for this variability and randomness. The market research was concluded with the analyses of the current simulation solutions in the market. The next step in the design phase was the introduction of the new supply chain planning methodology. The main purpose of this new methodology is to use the power of modelling and simulation to improve the initial supply chain performance. This methodology focuses on initial supply chain design, analyses and optimisation. By introducing this methodology organisations are now able to compare current supply chains with an unlimited realm of possible future configurations .... and without disrupting the initial day-to-day operations of an actual supply chain. The methodology is also designed to help predict the supply chain performance in terms of throughput, tardiness, utilisation, profitability, and other key performance indicators ... In order to experience real-life supply chain problems a case study has been done. This case study is about the automotive industry, which will include the ordering of parts assembly of vehicles, warehousing and distribution of vehicles. Different problems and difficulties were experienced. In conclusion, this case study provided a better insight into the behaviour of a supply chain. The case study was used to evaluate the use of this new methodology and as a result certain inefficiencies were recognized. As a result of the evaluation certain improvements need to be made to the supply chain methodology in order to make it more suitable for the market. These improvements would focus on inventory planning, supply chain analysis as well as database integration. The result of the case study also showed that the supply chain planning methodology is now set to develop a supply chain solution on the lowest level. There is however a need to be able to grow this supply chain methodology from a low level to a relatively high level. These functions are among others higher-level planning modules, which focus on transportation, production, demand and distribution and performance measurements. The focus will be to introduce these functions as objects. Every object will have the ability to design a supply chain solution on a high level or low level depending on the detail and requirements. ••• I also believe that the one who adapts his policy to the times prospers, and likewise that the one whose policy clashes with the demands of the times does not. 11 Niccolo Machiavelli, 1525 / Dissertation (MEng (Industrial Engineering))--University of Pretoria, 2006. / Industrial and Systems Engineering / unrestricted
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EFFEKTIVISERING AV BYGGLOGISTIK: TRANSPORT- OCH MATERIALFLÖDE : En fallstudie vid Årstastråket (Etapp 1) i StockholmBasharkar, Wahidullah January 2015 (has links)
The purpose of this study is to examine how construction logistics work for the ongoing project “Årstastråket” Stage 1, and to identify the logistics problems that the project may have. The aim then is to find solutions to these problems in order to avoid them in the upcoming projects. The study will include delopment of a standard template that can be used in logistics planning of the project. At the beginning of the study a comprehensive literature review of the available literature including reports and research articles was done to obtain a deeper knowledge of the subject in question. The result of this study is based on conducted case studies on the construction site, such as interviews and site visits. The majority of collection in the case study was mainly collected from 11 site visits, which then was supplemented with the information obtained from the interviews. The interviews were conducted with the local manager and supervisor of the project at “Årstastråket” Stage 1. In this study the construction logistics worked generally well, both in terms of transport- and material flow at the construction site. The main logistics problems identified in “Årstastråket” Stage 1 was particularly poor logistics planning of the project at an early stage, lack of visual communication and constant updating of construction site plan alongside project developing. The new developed standard template for logistics planning of the project at an early stage can be used in order to achieve the established goals and make the project even more effective.
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Improving supply chain competitiveness through the application of technology : a case study on a routing and scheduling systemHollander, Ryan 25 October 2010 (has links)
M.Comm. / In the last hundred years there has been a technological revolution that has forced people to change the way they live and run their organisations. This technological revolution has had a major impact on the business world. Coyle, Bardi and Langley (2003; 57) have suggested that “the rate of change has accelerated with consequent negative impacts if organisations do not change.” With today’s emphasis on cutting costs, streamlining expenses while at the same time trying to offer a competitive edge with regard to customer service, many organisations are looking to improve their bottom line and financial performance by implementing new technology into their supply chains. A popular way for organisations to speedily reap the benefits of having a more competent and competitive, technology-enabled supply chain, is by outsourcing their supply chain needs to a third party logistics organisations. The Star newspaper reported that, according to Brett Bowes, inefficiencies in the supply chain meant that fast-moving consumer goods manufacturers and retailers were losing R7 billion every year (The Star, 16 March 2007; 2). Although there are many auxiliary benefits and advantages of implementing software systems into the supply chain, the two critical benefits which justify the expense are reduced costs and improved customer service. Implementing technology is a costly, challenging and sometimes risky endeavor. This often results in an unwillingness to change until these organisations outgrow their systems, or the business environment becomes so complex, that they are forced to implement new technology. This hesitancy to introduce new technology timeously could hamper the progress and growth of these organisations, and could also affect their competitiveness in a highly competitive environment. The purpose of this case study is to compare the benefits achieved from existing older technology to new technology, based on a routing and scheduling case study in a large 3PL organisation.
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Optimalizace inbound logistiky u vybrané společnosti v automotivu / Optimization of inbound logistics in selected company from automotive industryKuljačková, Tereza January 2012 (has links)
The Master's Thesis is focused on optimization of inbound logistics of Toyota Peugeot Citroën Automobile. The aim of the Master's Thesis is analysis of current status of logistics in TPCA and detailed observation and research of logistic processes and routes with emphasis on the planning system. Factors affecting the decision making during logistics planning and process of information searching were identified with special attention for milk-routes. First chapter describes development of logistics a specifics of logistics in automotive industry. Following chapter analyse current status of logistics, types of logistic routes a system of the planning. Third chapter propose options for logistics planning optimization with help of improved information source obtaining, study the suitability of used logistics routes and test possibilities of utilization of commercial software. Last chapter of thesis is comparing logistics of TPCA and Škoda Auto.
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Commercial Drones: From Rapid Adoption to Sustainable Logistics PlanningMolavi, Nima, PhD January 2021 (has links)
No description available.
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Modelo para planejamento e controle logístico de obras de sistemas pré-fabricados do tipo engineer-to-order com o uso de BIM 4DBortolini, Rafaela January 2015 (has links)
O planejamento e controle logístico cumpre um importante papel no processo de montagem de sistemas construtivos pré-fabricados, e pode ter um impacto substancial nas metas do empreendimento em termos de prazo, custo, qualidade e segurança. A falta de planejamento logístico na construção pode causar congestionamento em postos de trabalho e resultar em baixa produtividade. Building Information Modeling (BIM) tem sido apontado como uma grande oportunidade para a melhoria do desempenho da logística de canteiros, principalmente pelo uso de modelos 4D para analisar planos de construção, assim como reduzir conflitos espaciais em canteiros de obras. Entretanto, modelos 4D têm sido frequentemente utilizados simplesmente para representar a sequencia de execução definida em uma rede CPM, sem considerar atividades que não agregam valor, tais como estoques e transporte. Visando a preencher esta lacuna, esta pesquisa propõe um modelo para o planejamento e controle logístico para sistemas construtivos pré-fabricados do tipo engineer-to-order, utilizando BIM 4D. Pesquisa construtiva foi a abordagem metodológica adotada nesta pesquisa. Quatro estudos empíricos foram realizados em diferentes canteiros de obras de uma empresa de estrutura metálica, nos quais processos logísticos foram planejados e controlados. O estudo também propôs diretrizes para integrar o planejamento logístico ao planejamento e controle da produção e para o uso de gestão visual para apoiar o controle logístico. O modelo proposto sugere que o desenvolvimento e uso de modelos 4D para controle e planejamento logístico deve ter uma ampla participação de diferentes intervenientes. / Logistics planning and control plays a key role in the process of assembling prefabricated building systems, and can have a major impact in project goals in terms of schedule, cost, quality and safety. The lack of construction logistics planning may cause congestion in workspaces and result in low productivity. Building Information Modeling (BIM) has been pointed out as a major opportunity for the improving the performance of site logistics, especially by using 4D models to analyze construction plans as well as to reduce spatial conflicts in construction sites. However, 4D models have been often used simply for representing the installation sequence defined in a CPM network, without considering non value-adding activities, such as inventories and transportation. In order to fill this gap, this research work proposes a logistics planning and control model for engineer-to-order prefabricated building systems using BIM 4D. Constructive research was the methodological approach adopted in this investigation. Four empirical studies were carried in different construction sites of a steel fabricator company, in which logistic processes were planned and controlled. This study also proposes guidelines for integrating logistics planning and control with production planning and control, and for the use of visual management to support logistics control. The proposed model suggests that the development and use of 4D models for logistics planning and control should have a broad participation of different stakeholders.
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Modelo para planejamento e controle logístico de obras de sistemas pré-fabricados do tipo engineer-to-order com o uso de BIM 4DBortolini, Rafaela January 2015 (has links)
O planejamento e controle logístico cumpre um importante papel no processo de montagem de sistemas construtivos pré-fabricados, e pode ter um impacto substancial nas metas do empreendimento em termos de prazo, custo, qualidade e segurança. A falta de planejamento logístico na construção pode causar congestionamento em postos de trabalho e resultar em baixa produtividade. Building Information Modeling (BIM) tem sido apontado como uma grande oportunidade para a melhoria do desempenho da logística de canteiros, principalmente pelo uso de modelos 4D para analisar planos de construção, assim como reduzir conflitos espaciais em canteiros de obras. Entretanto, modelos 4D têm sido frequentemente utilizados simplesmente para representar a sequencia de execução definida em uma rede CPM, sem considerar atividades que não agregam valor, tais como estoques e transporte. Visando a preencher esta lacuna, esta pesquisa propõe um modelo para o planejamento e controle logístico para sistemas construtivos pré-fabricados do tipo engineer-to-order, utilizando BIM 4D. Pesquisa construtiva foi a abordagem metodológica adotada nesta pesquisa. Quatro estudos empíricos foram realizados em diferentes canteiros de obras de uma empresa de estrutura metálica, nos quais processos logísticos foram planejados e controlados. O estudo também propôs diretrizes para integrar o planejamento logístico ao planejamento e controle da produção e para o uso de gestão visual para apoiar o controle logístico. O modelo proposto sugere que o desenvolvimento e uso de modelos 4D para controle e planejamento logístico deve ter uma ampla participação de diferentes intervenientes. / Logistics planning and control plays a key role in the process of assembling prefabricated building systems, and can have a major impact in project goals in terms of schedule, cost, quality and safety. The lack of construction logistics planning may cause congestion in workspaces and result in low productivity. Building Information Modeling (BIM) has been pointed out as a major opportunity for the improving the performance of site logistics, especially by using 4D models to analyze construction plans as well as to reduce spatial conflicts in construction sites. However, 4D models have been often used simply for representing the installation sequence defined in a CPM network, without considering non value-adding activities, such as inventories and transportation. In order to fill this gap, this research work proposes a logistics planning and control model for engineer-to-order prefabricated building systems using BIM 4D. Constructive research was the methodological approach adopted in this investigation. Four empirical studies were carried in different construction sites of a steel fabricator company, in which logistic processes were planned and controlled. This study also proposes guidelines for integrating logistics planning and control with production planning and control, and for the use of visual management to support logistics control. The proposed model suggests that the development and use of 4D models for logistics planning and control should have a broad participation of different stakeholders.
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Modelo para planejamento e controle logístico de obras de sistemas pré-fabricados do tipo engineer-to-order com o uso de BIM 4DBortolini, Rafaela January 2015 (has links)
O planejamento e controle logístico cumpre um importante papel no processo de montagem de sistemas construtivos pré-fabricados, e pode ter um impacto substancial nas metas do empreendimento em termos de prazo, custo, qualidade e segurança. A falta de planejamento logístico na construção pode causar congestionamento em postos de trabalho e resultar em baixa produtividade. Building Information Modeling (BIM) tem sido apontado como uma grande oportunidade para a melhoria do desempenho da logística de canteiros, principalmente pelo uso de modelos 4D para analisar planos de construção, assim como reduzir conflitos espaciais em canteiros de obras. Entretanto, modelos 4D têm sido frequentemente utilizados simplesmente para representar a sequencia de execução definida em uma rede CPM, sem considerar atividades que não agregam valor, tais como estoques e transporte. Visando a preencher esta lacuna, esta pesquisa propõe um modelo para o planejamento e controle logístico para sistemas construtivos pré-fabricados do tipo engineer-to-order, utilizando BIM 4D. Pesquisa construtiva foi a abordagem metodológica adotada nesta pesquisa. Quatro estudos empíricos foram realizados em diferentes canteiros de obras de uma empresa de estrutura metálica, nos quais processos logísticos foram planejados e controlados. O estudo também propôs diretrizes para integrar o planejamento logístico ao planejamento e controle da produção e para o uso de gestão visual para apoiar o controle logístico. O modelo proposto sugere que o desenvolvimento e uso de modelos 4D para controle e planejamento logístico deve ter uma ampla participação de diferentes intervenientes. / Logistics planning and control plays a key role in the process of assembling prefabricated building systems, and can have a major impact in project goals in terms of schedule, cost, quality and safety. The lack of construction logistics planning may cause congestion in workspaces and result in low productivity. Building Information Modeling (BIM) has been pointed out as a major opportunity for the improving the performance of site logistics, especially by using 4D models to analyze construction plans as well as to reduce spatial conflicts in construction sites. However, 4D models have been often used simply for representing the installation sequence defined in a CPM network, without considering non value-adding activities, such as inventories and transportation. In order to fill this gap, this research work proposes a logistics planning and control model for engineer-to-order prefabricated building systems using BIM 4D. Constructive research was the methodological approach adopted in this investigation. Four empirical studies were carried in different construction sites of a steel fabricator company, in which logistic processes were planned and controlled. This study also proposes guidelines for integrating logistics planning and control with production planning and control, and for the use of visual management to support logistics control. The proposed model suggests that the development and use of 4D models for logistics planning and control should have a broad participation of different stakeholders.
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