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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.
1

An analytical investigation into lead-time reduction in the manufacturing sector : a study of discrete manufacturing in Kurdistan region of Iraq

Jaff, Twana Abdlkader Husain January 2016 (has links)
The dynamic business environment has prompted the companies to improve their competitiveness in terms of manufacturing efficiencies by exploring faster, better and cheaper modes of product development. In this concern, different approaches are configured such as lean manufacturing, just in time and lead time reduction. The study focuses on a critical investigation into the reduction of Lead Time within discrete manufacturing in Kurdistan region of Iraq and the reasons behind this research, that area has evolved gradually as well as the government has an action plan for national recovery and development of reconstruction, where lead-time has become a major issue in manufacturing industry. Specifically, current research study aims at contributing to the strand by focusing on a critical investigation into the reduction of lead time within discrete manufacturing in Kurdistan region of Iraq, where lead-time has become a major issue in manufacturing industry. Mainly, the study has the goals of developing reliable techniques for reducing the lead time through application of assessment survey, capacity planning and key performance indicators in order to implement and control the manufacturing processes. The rationale behind the present study is consisted of economic development within the region, which has attracted a large number of foreign direct investments, but the expanded lead time is causing hurdles with the lack of a strategic plan for resolving the issue which has not keenly addressed in literature so current study would be beneficial for both the stakeholders such as researchers relying on literature and for practitioners as well. In order to conduct the analysis, current research applies the mixture of quantitative and qualitative research. Specifically, for quantitative analysis, a survey is conducted using questionnaires as data collection tool and SPSS analysis for exploring the cause and effect relationship. Mainly, the data are collected from eight Kurdistan based manufacturers. On the contrary, the qualitative analysis is conducted through the case studies. The development of a comprehensive conceptual framework has been applied for focusing on quick response manufacturing both at batch and mass production level. The framework is a contribution to academic knowledge. Through the outcomes of the study, specific factors which are explored to be the main causes of extension in lead time include ineffective forecasting for material requirements, capacity planning, inaccurate demand analysis, decreased resource efficiency and shipment delays. As the most effective solution to these issues, the findings explained that the lot for lot technique is much better than the fixed period requirements which are mostly used in the Iraq region. Moreover, just in time manufacturing strategy and closed loop capacity is also proven to be fruitful along with the splitting order tactic. It is concluded from the findings of this study that the basic issue lies with management in different areas like in human resource, quality, information acquiring, technological developments and operational efficiency. So, it is recommended to the practitioners to higher efficient management squad at the most basic level to eradicate the root cause of the lead time issue. This research will provide new simple strategies for reducing manufacturing lead-time because this is particularly important, as it can be used to provide guidance to industry practitioners on how to reduce manufacturing lead time.
2

Lead time analysis from order to delivery : A study of lead time in the material flow and the information flow for the aftermarket at Siemens Industrial Turbomachinery AB

Zetterström, Filippa, Ek, Niklas January 2015 (has links)
Siemens Industrial Turbomachinery AB (SIT) is a company that produces and delivers medium sized industrial gas turbines to customers all over the world and is located in Finspång. The Service section of SIT handles the aftermarket of turbines with both planned and unplanned inspections/repairs. SIT-Service experience that their lead time to customers is too long and a yearly survey with customers confirmed this. Service strives for a higher customer service and since the company suspect that internal processes have safety time built into can time quickly build up. Service has different service lines depending on what kind of maintenance needed and if planned/unplanned. Different options in a combination with several departments involved in these big projects make the flow hard to visualize and makes it complex.This report has studied how SIT-Service can enable a lead time reduction from order to delivery where the flow for Parts was chosen to be mapped and analyzed for one of the service lines. This orientation of the study was partly based on directions from the company and partly delimitations by the writers of the report. Directions from the company were for example to investigate a standard scope and to visualize the flow by mapping it, all with a focus on lead time. Delimitations developed to exclude sales and transportations as well as to only investigate one turbine type and one service line. To be able to follow the flow was a decision made to investigate the flow for Parts.The study has mapped times and activities in the Parts flow from received purchase order (PO) from customer to when parts are ready to leave SIT Finspång. This mapping includes several departments and several transactions in the ERP-system, activities, tasks, queues and uncertainties. The mapping investigated how the lead time was built up by the system and one angle of the mapping was to investigate if the times in the system were consistent with the matching times in reality. To be able to suggest any changes in the Parts flow regarding lead time, the mapping was classified based on value-adding/non-value-adding, wastes, critical chain and bottlenecks. This was followed by a use of different principles in how to enable lead time reduction. These principles were: elimination, simplification, parallelization and a combination of critical chain and bottlenecks.The results and conclusions based on the two analysis parts have been divided into two parts where suggestions in the first one are believed to have a larger impact on the total lead time. This part consists of five big areas of time with several suggestions, from concrete to more general. One of the most important areas is that SIT needs to improve how the company uses the Planned delivery time; to standardize and to make sure that it is used in the same way by all involved which could eliminate unnecessary times built in. Another important area is that the Goods receiving process time could be reduced for a majority of material in the ERP-system since this differs today even if material is handled the same in reality. The second part consisting of 14 smaller areas of suggestions are believed to have a smaller impact on the total lead time but are still considered to be important to implement. All suggestions have an order of implementation which recommends what should be done first for SIT-Service. If the suggestions are implemented is it believed that SIT-Service can shorten the lead time in the Parts flow and also to get a more efficient organization.
3

Optimal sublot determination in multiple batch stage, two stage production systems

Doutriaux, Frederic 12 March 2009 (has links)
One of the main objectives in the operation of production systems these days is to reduce production lead time. A reduction in production lead time directly translates into decrement in production cost thereby making the products competitive. One way to achieve this objective is to overlap operations among the machines by splitting the batches to process into sub lots. The technique used to split batches into sub lots is the Lot Streaming method. In this thesis, the Lot Streaming problem is mathematically analyzed for the multiple batch/two-machine case under the criteria of minimizing the production cost which consists of handling cost and makespan cost. The work is focused on the determination of the number of sub lots in each batch for both the continuous and integer versions of the problem. First, we solve the two batch/two-machine problem, which is a special case of the multiple batch/two-machine problem and is simpler in nature. A no-idling constraint is proven to be necessary for the minimization of the criteria considered. This constraint is used to reduce the size of the problem to a single dimension problem which allows the use of a line search method. A continuous optimal solution is generated and an algorithm is proposed to deduce an integer solution from it. The results of the two-batch problem are then generalized to the multiple batch/two-machine case, which is solved for both the continuous and integer versions of the problem. / Master of Science
4

Reducing Supplier Lead Time : - A case study on Supplier Lead Time at purchasing companies

Jönsson, Johanna, Luong, Melinda January 2015 (has links)
Title: Reducing Supplier Lead time – a case study on Supplier Lead Time at purchasing companies Authors: Johanna Jönsson and Melinda Luong Tutor: Dr. Åsa Gustavsson Examiner: Dr. Lars-Olof Rask Course code: 4FE06E - Master Thesis _________________________________________________________________________ Research questions: ●  How are companies working with and defining Supplier Lead Time? ●  What activities are included to reduce Supplier Lead Time? ●  How can companies further develop their work to reduce Supplier Lead Time? Purpose: The purpose of this Master Thesis is to describe and explain how purchasing companies are working to reduce Supplier Lead Time, in order to maintain or achieve an efficient and flexible supply chain. Moreover the study aims to recommend what approaches companies could further use to reduce Supplier Lead time. Method: To answer these research questions the authors have done two case studies. The theoretical material has been collected and processed, which has formed the basis for the semi-structured interview guide that was answered by the interviewees. The authors also attended meetings to get other inputs about the subject. Conclusion: IKEA Components are today taking different actions to improve the SLT but can improve their volume agreements (AGV) by aligning all involved parts and have a functional leader that makes sure that they follow it up. At IKEA IMS the authors recommend them to work with volume commitments with suppliers and develop a clearer structure for who is responsible for improving the SLT and evaluating it. Keywords Supply chain management, Supplier Lead Time, Reducing Supplier Lead Time, Organization management, Performance evaluation
5

Quick response manufacturing (QRM) uma alternativa para redução do lead time na área produtiva de uma empresa de materiais de escrita

Saes, Elizangela Veloso 20 August 2010 (has links)
Made available in DSpace on 2016-06-02T19:51:45Z (GMT). No. of bitstreams: 1 3196.pdf: 1584882 bytes, checksum: e87305ed1643450b13fc00d6bac58c63 (MD5) Previous issue date: 2010-08-20 / The approach Quick Response Manufacturing (QRM) has been proposed in the late ninety, and since then, has been successfully deployed in many companies, achieving promising results in reduction of lead time in environments with high product variety. This approach, although already established abroad, mainly in the United States, is poorly known in Brazil as not to have official records of its practice, thus providing a vast new area of research. From this context that this dissertation aims to explore and understand the general ways to reduce lead time based on QRM and propose a practical application of this approach. For this objective to be achieved, we sought, first, the comprehensive review of the literature concerning the reduction of lead time, describing the tools and principles to reduce lead time in the QRM approach and then propose to implement some of the principles and tools of QRM in the production area in a business of writing. This proposed implementation of QRM is analyzed and validated by simulations that visualize the interactions of variables from the factory floor and the effects of these variables in the percentage of use of sectors in the intermediate level of inventory (WIP) and lead time. It is hoped that the practical implementation of the proposals to reach a 55% reduction from the current level of WIP company and up to 77% in the average lead time of its products. Thus, this research contributes to the theory and practice in management of manufacturing systems, showing the importance of reducing lead time and the effects and benefits of implementing QRM in a Brazilian company. / A abordagem Quick Response Manufacturing (QRM) foi proposta no final da década de noventa e, desde então, vem sendo implementada com sucesso em inúmeras empresas, atingindo promissores resultados na redução de lead time em ambientes com alta variedade de produtos. Essa abordagem, embora já estabelecida no exterior, principalmente nos Estados Unidos, ainda é pouco conhecida no Brasil a ponto de não possuir registros oficiais de sua aplicação prática, proporcionando, assim, uma nova e vasta área de pesquisa. A partir desse contexto que surge essa dissertação que tem como objetivo geral explorar e entender as formas para a redução de lead time com base no QRM e propor a aplicação prática dessa abordagem. Para que este objetivo fosse alcançado, buscou-se, primeiramente, a revisão integral da literatura a respeito de redução do lead time, descrevendo as ferramentas e os princípios para a redução de lead time na abordagem QRM; em seguida, propô-se a implementação de alguns dos princípios e ferramentas do QRM na área de produção em uma empresa de materiais de escrita. Essa proposta de implementação do QRM é analisada e validada por simulações que permitem visualizar as interações das variáveis do chão-de-fábrica e os efeitos dessas variáveis no percentual de utilização dos setores, no nível de estoque intermediário (WIP) e no lead time. Espera-se que a implementação na prática das propostas apresentadas atinja uma redução de 55% do nível atual de WIP da empresa e de até 77% no lead time médio de seus produtos. Dessa forma, essa pesquisa pretende contribuir com a teoria e a prática em gestão de sistemas de manufatura, mostrando a importância da redução do lead time e os efeitos e benefícios da implementação do QRM em uma empresa brasileira.
6

Bättre sent än aldrig – eller? : En kvantitativ studie om årsredovisningars aktualitet

Hansson, Emil, Nielsen, Linn January 2020 (has links)
Syfte: “Studiens syfte är att undersöka vad som förklarar svenska onoterade företags benägenhet att lämna in sin årsredovisning i ett tidigt eller sent skede”.   Metod: I denna kvantitativa studie har sekundärdata samlats in från databasen Retriever. För att uppnå studiens syfte används multivariata regressionsanalyser med lead time och i tid/sen som beroende variabler och lönsamhet, ålder, storlek, revision, skuldsättning, bokslutsmånad samt bransch som oberoende variabler.   Resultat och Slutsats: Resultaten visar på ett negativt signifikant samband mellan lead time och lönsamhet. Sambandet mellan lead time och företagets bokslutsmånad var positivt och signifikant. Företagens val att ha revisor visade sig även det ha ett positivt signifikant samband med lead time, vilket innebär att företag med revisor kommer att lämna in sin årsredovisning senare än företag utan revisor. Det finns däremot inget som tyder på att ha en revisor eller inte påverkar huruvida företag lämnar i tid eller inte.   Bidrag: Studien har bidragit till forskningsområdet kring aktualitet dels genom att utföra studien i Sverige och dels genom att studera onoterade företag. Detta har medfört att en variabel som inte tidigare har studerats, företagets val att ha revisor eller inte, har kunnat inkluderas. Studien bidrar även till de senaste årens debatt kring tidsgränsen för hur sent årsredovisningar ska få lämnas in.   Förslag till vidare forskning: Ett förslag till vidare forskning är att studera om årsredovisningars aktualitet förändrades i och med avskaffandet av revisionsplikten. Det hade även varit intressant att utföra en liknande studie med longitudinell design där flera år undersöks för att kunna fastställa orsaksriktningen mellan variablerna. / Aim: “The aim of this study is to examine what explains Swedish unlisted companies’ tendency to file their annual reports in an early or late period”.   Method: In this quantitative study secondary data is obtained from the database Retriever. To achieve the aim of this study multivariate regression analyses are used with lead time and in time/late as the dependent variables and profitability, age, size, audit, leverage, fiscal year-end and sector as independent variables.   Results and Conclusions: The results show a negative relationship between lead time and profitability. The relationship between lead time and company fiscal year-end was positive and significant. If a company have chosen to have an auditor is shown to have a positive significant relationship with lead time, this mean that companies with an auditor will file their annual reports later than companies without an auditor. There is on the other hand no indications that having an auditor or not will affect whether the company file on time or not.   Contributions: This study has contributed to the field of research of timeliness partly by performing the study in Sweden and partly by studying unlisted companies. This resulted in the inclusion of a variable that takes into account if the company has an auditor or not, which has not been studied before. The study also contributes to previous years debate about the time allowed for companies to file their annual reports.   Suggestions for future research: A suggestion for future research is to study if the timeliness of annual reports changed as a result of the abolition of the audit obligation. It would also be interesting to conduct a similar study with a longitudinal design where more than one year is reviewed so that the causal direction of the variables can be determined.
7

Reducing internal lead times in MTO & job-shop production environments: a case study

Todeti, Vamsikrishna, Jally, Kalyanchakravarti January 2013 (has links)
This Master’s thesis has been carried out within the subject area of Production Development and Management and aims to reduce internal lead times in make-to-order (MTO) and job-shop production environments with the use of identified theoretical methods. The reason this particular production environment was chosen was the flexibility and satisfaction it provides its customers. Today, customers expect customised products, a situation which causes problems for manufacturers as they are unable to produce such products in large amounts. In order to investigate problems with these kinds of environments and the causes for long lead times, we have conducted a literature study where we identified the problems these particular kinds of production environments experience regarding production planning and control which are related to the immense amount of time consumed by changeovers because of high demand variance and high requirements for customisation. To affirm the theoretical findings, we opted to undertake a case study and chose Talent Plastics Gislaved AB as our case, because this company utilises an MTO and job-shop production environment for its production of highly customised products with high demand variance. In the analysis of our case, we found that the wastes in the organisation were similar to those identified in the theoretical findings. The current planning system and the current state of the manufacturing lead time system were evaluated and a theoretical framework using a combination of lean production, work load control and constant work-in-process theories was suggested. We claim that concentrating on the reduction of setup times can lead the job-shop towards drastically decreased lead times and a much more effective use of time throughout the organisation. Because the organisation will continue to face problems due to the ever-increasing demand variance and requirements for customisation, there are plenty of opportunities for further research in these kinds of production environments. Emerging theories, such as quick response manufacturing, may also be tested to construct an efficient framework.
8

The Effect of Variability Imbalance on Lead Time

rokni, mitra January 2022 (has links)
This master's thesis investigates the impact of unbalanced variability on lead time using a simulation-based optimization approach. Based on the hypothesis, variation of service time has a strong effect on lead time. It has also been hypothesized that placing the high variable station, in terms of CVp, at the end of the line will increase lead time. To evaluate these hypotheses, Fact Analyzer Simulation Software version beta7 was used to simulate and optimize two different models. First, the effect of an imbalanced line in terms of service time on total lead time in a simple production line hypothetical model was investigated. In the second part of this master thesis, a real health care model was adopted from Frandsen and Engqvist’s project at Skaraborg Hospital (SkaS). By optimizing this model, using NSGA_II Algorithms, the effect of variance and mean of service time on lead time variance and mean were evaluated and compared. As a result of both the hypothetical and health care models, the total lead time will not decrease by reducing the variance of service time, indicating that the hypothesis should be rejected.    Keywords: service time, CVp, lead time, imbalanced, variability, mean lead time, variance lead time, waiting time, variability
9

Lead Time Reduction Case study:BEAB etikett & system AB

Hassanzadeh Rad, Marjan January 2008 (has links)
In today’s competitive business world, companies require small lead times, low costs andhigh customer service levels to survive. Because of this, companies have become morecustomer focused . The result is that companies have been putting in significant effort toreduce their lead times.The purpose of this master thesis was to reduce lead time at BEAB etikett & system AB(BEAB) by focusing both on ordering and production times. In order to achieve this allprocesses from receiving an order to shipment of the order are mapped in a current statemap. Some changes based on the Toyota Production System (TPS) were implemented.The results were then mapped in a future state map.BEAB has more than 30 years experience of producing labels in different sizes andshapes. The products’ range varies from hanger labels on clothing to self adhesive labelsfor pallets. Due to globalization and stiff competition, the 8 days lead time at BEAB hasto be reduced so that they could maintain their customers, and even increase theircustomer base.It was found that the most appropriate mapping method for lead time reduction wasValue Stream Mapping (VSM). From the results achieved by VSM it was obvious thatthe press machines were bottlenecks. In order to increase their capacity, their change overtime should be reduced. Another observation derived from the VSM, was that a neworder passing through the ordering department is an unnecessary step. Some otherrecommended changes based on applying TPS are:• Reduction of work in process inventory (WIP)• Reduction of waiting time between press and converter• Stop the process to build in quality (this sounds awkward)• Collect more information• Implementation of the 5S methodologyBy implementing these changes, the future state map was created and the total lead timewas reduced from 8 days to 6 days. The production lead time reduced from 4.35 days to 4days. / Uppsatsnivå: D
10

XLPE-cable Production Optimization : Setup time Reduction at Armoring line

Hedlund, Björn January 2014 (has links)
At ABB’s high voltage cable factory in Karlskrona, there is a line production that is regarded as a bottleneck. The production rate at this workplace as well as the large variations of setups has created two major problems. The first problem is that it has become difficult for the planning department to determine the lead times for delivery to the customers. The other problem is that the long setup times has made this line production the bottleneck of the whole production. The factory at ABB HVC includes a number of line productions, where each line has their own purpose and value adding processes. The armoring line AR50 that this project has the focus to improve has the last value adding processes for the factory’s main product. The factory’s main product is the Cross-Linked Polyethylene cable, shortened XLPE. There are several different advantages with the XLPE-cable system. First of all they are maintenance-free and environmentally friendly. The main reason that the XLPE-cable is environmentally friendly is because it have low electrical losses. Since the submarine cables are underground the cables are invisible and not effected by weather conditions. This project implements the method SMED as well as various methods from the LEAN transcript in order to reduce the setup times and create a more stable and effficient production. An Ishikawa diagram were used in order to determine the root causes of the problems. Later both technical and management solutions were proposed and implemented. The project has concluded impressive results regarding setup time reduction and annual cost savings. It also enlightens the large potential for further improvement. This project will be continued during the year of 2014 in order to implement the proposed solutions. The future improvements are not just technical but also related to management and group dynamics.

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