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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.
21

Optimalizace vnitřního materiálového toku / Optimization of internal material flow

Kovář, Miroslav January 2010 (has links)
This thesis refers about the optimalization of internal business logistics system. This thesis want to explore and propose new solutions to the system of internal transport of material in a manufacturing company. The aim is find a suitable methodology for the problem and aplication this methodology to the particular case. The practical part describes the specific case of the production system in the Bosch Diesel s.r.o. at his plant in Jihlava. Description includes an overview of the current state of the logistical arrangements and problems that a rise from the current state. Compares the current state with the proposed state and investigates the various pros and cons. Part of the analysis is a computer simulation of the transport system, which has been support to confirming the appropriateness of the proposed solutions.
22

Assessment of Urban Metabolism of Stockholm Royal Seaport : Through the Enhanced Economy Wide Material Flow Accounting Framework

Abrishami, Sina January 2020 (has links)
Material flows in Urban Metabolism play a key role for the purpose of building urban areas and growing the economy. There is lack of standard method for accounting of material flows within and across the boundaries of urban systems. This thesis aims to assess the Urban Metabolism of small-scale urban area through the application of the Economic Wide Material Flow Analysis and enhance the scope of the method by adding water flows, which could potentially become a basis for the development of the method in the future. First, the application of the Economic Wide Material Flow Analysis in urban areas was studied through a literature review and then the enhanced Economic Wide Material Flow Analysis was applied to Stockholm Royal Seaport using bottom-up data. Using bottom-up data resulted in detailed information, however, full comparison between urban areas was not possible due to data gaps. The results showed the importance of the method for enhancing Urban Metabolism analysis and amending resource management. Spotting available secondary and recycled resources in the socioeconomic system as a part of application of the method is beneficial to sustain the natural resources use. Since still the method is developing for small-scale urban areas, a mixture of this method and other recommended methods by having focus on data collection is suggested for integrating databases and comprehensive analysis. / Under de senaste decennierna har stadsområden expanderat snabbare än tidigare. Genom att öka människors tendens att bo i stora städer kommer naturresurser att behövas för att tillgodose stadsområdens växande behov. Materialflöden i stadsmetabolismen spelar en nyckelroll för att bygga miljövänligt och växande ekonomin. Det saknas en standardmetod för redovisning av materialflöden inom och över gränserna för stadssystem. Denna avhandling syftar till att utvärdera stadsmetabolismen genom att använda tillämpning av bred ekonomisk materialflödesredovisning och förbättra metodens omfattning genom att lägga till vatten- och genomströmningsflöden som potentiellt kan bli bas för utvecklingen av metoden i framtiden. Först studerades tillämpningen av ekonomiskt bred materialflödesredovisning i urbana områden genom litteraturöversikt och sedan tillämpades den förbättrade analysen av ekonomiskt bred materialflöde på Norra Djurgårdsstaden med hjälp av bottom-up data. Att använda bottom-up-data resulterade i detaljerad information, men fullständig jämförelse mellan stadsområden var inte möjlig på grund av dataklyftan Resultaten visade vikten av materialflödesredovisning för att förbättra urban metabolismanalys och ändra resurshantering. Att hitta tillgängliga sekundära och återvunna resurser i det socioekonomiska systemet som en del av tillämpningen av metoden är fördelaktigt för att upprätthålla användningen av naturresurser. Eftersom metoden fortfarande utvecklas för småskaliga stadsområden föreslås en blandning av denna metod och andra rekommenderade metoder såsom, livscykelbedömning, genom att fokusera på datainsamling för att integrera databas och omfattande analys.
23

Effektiv lagerstyrning med AHP och tvådimensionell artikelklassificering : En fallstudie på Permobil AB, Timrå

Andersson, Erik January 2016 (has links)
Costs related to inventory are usually a significant amount of the company’s total assets. Despite this, companies in general don’t pay a lot of interest in it, even if the benefits from effective inventory are obvious when it comes to less tied up capital, increased customer satisfaction and better working environment. Permobil AB, Timrå is in an intense period when it comes to revenue and growth. The production unit is aiming for an increased output of 30 % in the next two years. To make this possible the company has to improve their way to distribute and handle material,The purpose of the study is to provide useful information and concrete proposals for action, so that the company can build a strategy for an effective and sustainable solution when it comes to inventory management. Alternative methods for making forecasts are suggested, in order to reach a more nuanced perception of different articles, and how they should be managed. Analytic Hierarchy Process (AHP) was used in order to give specially selected persons the chance to decide criteria for how the article should be valued. The criteria they agreed about were annual volume value, lead time, frequency rate and purchase price. The other method that was proposed was a two-dimensional model where annual volume value and frequency was the criteria that specified in which class an article should be placed. Both methods resulted in significant changes in comparison to the current solution. For the spare part inventory different forecast methods were tested and compared with the current solution. It turned out that the current forecast method performed worse than both moving average and exponential smoothing with trend. The small sample of ten random articles is not big enough to reject the current solution, but still the result is a reason enough, for the company to control the quality of the forecasts. / Kostnader kopplade till lagerverksamheten är ofta en betydande del av företagets totala omsättning. Trots detta är generella intresset för effektiv lagerstyrning lågt, trots dokumenterade fördelar som mindre bundet kapital, ökad kundservice och bättre arbetsmiljö. Permobil AB, Timrå är inne i en tillväxtfas och siktar på att öka sin produktion med mer än 30 % inom två år. För att möjliggöra detta behöver företaget förbättra sin lagerstyrning och utveckla sitt sätt att distribuera material, dels till eftermarknad och dels till sin egen montering. Syftet med studien är att bistå företaget i dess önskan att skapa en effektivare lagerstyrning med avseende på kvalitet och kostnad. Alternativa metoder att klassificera artiklar föreslogs, för att skapa en mer nyanserad bild av en artikels karaktär och hur den ska styras. Analytic Hierarchy Process (AHP) användes för att ge utvalda nyckelpersoner en chans att bestämma kriterier för hur en artikel ska bedömas. Dessa kriterier var årligt volymvärde, ledtid, uttagsfrekvens och inköpspris. Den andra metoden som föreslogs var en tvådimensionell klassificering där årligt volymvärde och uttagsfrekvens delar in befintliga artiklar i nio klasser med olika prioritering. Båda metoder gav upphov till betydande förändringar i jämförelse med den nuvarande metoden. För reservdelslagret testades alternativa prognosmetoder, för att jämföra med den nuvarande. Det visade sig att de båda metoderna glidande medelvärde och exponentiell utjämning med trend presterade bättre än den befintliga metoden. Stickprovet på 10 slumpmässigt utvalda artiklar är för litet för att förkasta nuvarande sätt att prognosticera, men det finns skäl att upprätta rutiner för kvalitetskontroll för att säkra en hög nivå på framtida prognoser.
24

INTERNAL LOGISTICS OF TENHULTSPRESSGJUTERI AB / LOGISTIK MELLAN GRANNFASTIGHETER PÅ TENHULTS PRESSGJUTERI AB

Holmgren, Anton, Karlsson, Julia January 2015 (has links)
Tenhults Pressgjuteri AB is facing growth in expansion, which results in need of bigger premises. The company has bought an adjoining property to overcome this problem. This thesis givessuggestions on how the logistics of these properties should be managed, which transport system is most suitable to use, where deliveries will take place and how the stock will be set upin the new premises. To obtain relevant data and information have a description of the facts, measurements and calculations been made. Selections and ratings have been used to develop suitable alternative solutions. The payback-method has been used to calculate the investments. A specially designed evaluation chart forms the basis of which transport system to be used. Lastly, a sensivity analysishas been conducted to determine how reliable the results are. Deliveries and inventory have been determined based on the choice of transport system.The thesis shows that the choice of transport system depends on the volumes that are carried, distance and environmental conditions. The market offers both automated transport systems and systems that require a driver. The automated transport system willnot be profitable whenthe cargo volume is too small since the investment costs are significantly higher. However, the operating costs are low which makes it profitable with an increased cargo volume. Closer analysis of existing production flow could provide a more credibleresult. What also must be taken into account is thatthe costs is not preciseand may differ in reality. The costs are assumed to be so lifelike that they do not affect the result more than marginally. / Tenhults Pressgjuteri AB befinner sig i en expansionsfasoch är i behov av större lokaler. För att lösa dettahar företaget köpt upp en grannfastighet. Denna rapport ger förslag på hur logistiken mellan dessa fastigheter skall skötas,vilket transportsystem som är lämpligt att använda, var utleveranserskall ske,samt ett förslag på hurlager kan ställas uppi den nya fabriken. För att erhålla relevant data och information har nulägesbeskrivningar, mätningar och beräkningar gjorts. Urval och värderingar har använts för att ta fram lämpliga alternativ på lösningar. För att beräkna investeringskostnader har payback-metoden använts och ett specialframtaget värderingsschema ligger som grund för valet av transportsystem. Slutligen har en känslighetsanalys gjorts för att bestämma hur pålitligt resultatet är. Utleverans och lager har bestämts utifrån valet av transportsystem för att synkronisera på bästa sätt. Arbetet visar att val av transportsystem beror påvilka volymer som fraktas, avstånd och miljöförhållanden. Marknaden erbjuder både automatiserade transportsystem och system som kräver chaufför. I detta fall är fraktvolymen för litenför att ett automatiserat system skall vara lönsamt eftersominvesteringskostnaderna för ett sådant system är betydligt högre. Däremot är driftkostnaderna lågaför ett automatiserat systemoch vid en större fraktvolym sparas dessa driftkostnaderin då ingen bemanningskostnad tillkommer.Närmare undersökning av befintligt produktionsflöde kunde ge ett mer trovärdigt resultat då arbetet baseras på beräkningar från olika portar. Det som också skall tas i beaktande är att kostnaderna inte är exakta och kan komma att avvika i verkligheten. Kostnaderna antas dock vara så verklighetstrogna att de inte påverkar resultatet mer än marginellt.
25

Prilog istraživanju uticaja raznosmernog tečenja metala na parametre procesa hladnog istiskivanja delova složenih geometrijskih oblika / A contribution to the investigation of divided material flow influence to the process parameters of complex shapes cold extrusion

Skakun Plavka 18 February 2015 (has links)
<p>U disertaciji je elaborirana mogućnost primene relaksirajućih otvora kod istiskivanja delova sa ozubljenjem u cilju smanjenja parametara procesa. Primenjena su dva modela deformisanja, kada je otvor u pripremku i kada je otvor u žigu. Metodom gornje granice izvr&scaron;ena je teorijska analiza procesa i kreirano re&scaron;enje na osnovu koga su određeni deformaciona sila, pritisak na žig i promena geometrije dela. Pomoću eksperimenta istiskivanja i numeričke simulacije procesa izvr&scaron;ena je verifikacija teorijskog re&scaron;enja. Teorijski, eksperimentalni i rezultati simulacije procesa su pokazali da primena relaksirajućih otvora na analizirane tipove ozubljenja dovodi do smanjenja deformacione sile i pritiska u procesu.</p> / <p>Possibility of flow relief openings applying in cold extrusion of gear-like elements in order to reduce the process parameters is elaborated in this thesis. Two different deformation models are analysed: when the opening is in the billet and when the opening is in the punch. Upper bound method was applied for the process analysis and determination of deformation force, punch pressure and change of part geometry. Extrusion experiment and numerical simulation of process are used for verification of theoretical solution. Theoretical, experimental and numerical results confirmed that application of flow relief openings enables reduction of deformation force and punch pressure in the process of gear-like elements extrusion.</p>
26

Global patterns of material flows and their socio-economic and environmental implications: a MFA study on all countries world-wide from 1980 to 2009.

Giljum, Stefan, Dittrich, Monika, Lutter, Franz Stephan, Lieber, Mirko 18 March 2014 (has links) (PDF)
This paper assesses world-wide patterns of material extraction, trade, consumption and productivity based on a new data set for economy-wide material flows, covering used materials for all countries world-wide between 1980 and 2009. We show that global material extraction has grown by more than 90% over the past 30 years and is reaching almost 70 billion tonnes today. Also, trade volumes in physical terms have increased by a factor of 2.5 over the past 30 years, and in 2009, 9.3 billion tonnes of raw materials and products were traded around the globe. China has turned into the biggest consumer of materials world-wide and together with the US, India, Brazil and Russia, consumes more than 50% of all globally extracted materials. We also show that the per-capita consumption levels are very uneven, with a factor of more than 60 between the country with the lowest and highest consumption in 2009. On average, each human being consumed 10 tonnes of materials in 2009, 2 tonnes more than in 1980. We discuss whether decoupling of economies' growth from resource use has occurred and analyse interrelations of material use with human development. Finally, we elaborate on key environmental problems related to various material groups.
27

Effektivare materialflöden med människan i centrum : En fallstudie inom BillerudKorsnäs godsmottagning

Jonuzi, Taulant, Sager, Josefin January 2019 (has links)
With the development of society, organizations are increasingly working to streamline their businesses to maintain and strengthen their position on the market. This can be carried out in several different ways, since businesses are individual and require special needs to develop longterm sustainability. The purpose of this case study is to emphasize how material flows within industrial goods reception can be streamlined based on human aspects. To answer the purpose, data was collected through interviews, observations and literature studies. Six interviews have been conducted at BillerudKorsnäs, with observations taking place continuously during the study. This is to create a reality perception with different approaches to increase the credibility of the study. The results were analyzed and discussed with the help of literature reviews. The literature studies consist of collected scientific articles, course literature, web pages and other credible sources. The results are based on a study of internal material flow in the central repository at BillerudKorsnäs in Gävle. As discovered, the material flow consists of mainly manual labor that lead to unnecessary time-consuming disturbances. A contributing factor to improve and streamline the material flow has been built on identifying health-promoting measures. Therefore, industrial goods reception can be made more efficient with the help of digital aids concerning to human aspects.
28

Effektivisering av informations- och materialflödet på byggarbetsplatsen / ​Efficiency of information and material flow at the construction site

Hajnal, Balazs, Lami, Taulant January 2017 (has links)
Byggbranschens största utmaning idag är strävan efter lägre kostnader, högre kapacitet, lägre slöserier och ökad effektivitet för att uppnå ett mer lönsamhet. För detta krävs det framförallt att slöseri och icke värdeskapande aktiviteter elimineras bort. Därmed är det viktigt att byggföretag börjar ta initiativ i att kartlägga det nuvarande informations- och materialflöden för att skapa sig en uppfattning om vilka möjligheter det finns för att hitta alternativa lösningar till effektivisering. Syftet med rapporten är att kartlägga informations-och materialflödet för att analysera och identifiera brister för att sedan effektivisera och minimera slöserierna som förekommer på byggarbetsplatsen. Utifrån kartläggning och analys skall resultatet av undersökningen vara till hjälp för att ta fram lämpliga förslag till framtida projekt. Vid början av examensarbetet gjordes en litteraturstudie av vetenskapliga rapporter, artiklar och facklitteratur för att kunna få en överblick och kunskap över ämnet. Resultatet av rapporten genomfördes av framförallt som mest fokus på fallstudier på byggarbetsplatsen, flertal besök på arbetsplatsen och strukturerade intervjuer. Datainsamlingen gjordes främst genom besök på byggarbetsplatsen för att kunna erhålla information genom observationer och intervjuerna som var till en stor hjälp. Författarna intervjuade projektchefen, arbetsledaren samt respondenter som arbetade kring projektet Hotell Victor. Dessutom gjordes fler intervjuer hos andra projekt och företag för att få förståelse över hur stort problem det är i allmänt egentligen. Ett flertal risker identifierades utifrån empirin, vilket lyfts upp och beskrivs likt troliga uppkomma risker, då det inte är sannolikt att dessa risker gäller inte enbart för AF Gruppen i Göteborg. ​ Resultatet från fallstudien tyder framförallt att kommunikationen mellan entreprenör och leverantör kräver en förbättring, det skulle bidra till kostnads- och tidsbesparingar. Aviseringen av material som anländer till byggarbetsplatsen är också ett problem , bristande avisering och kommunikation leder till att aktiviteter som omplanering, väntan och onödiga rörelser växer fram . / The construction industry's biggest challenge today is the quest for lower costs, higher capacity, lower waste levels and increased efficiency. For this, it is primarily necessary to eliminate waste and non-value-creating activities. Thus, it is important that construction companies begin to take the initiative in mapping current information and material flows to get an idea of ​​the possibilities for finding alternative solutions for efficiency.  The purpose of this thesis is to gain insight into what shortfalls as occurs in construction industry and to propose improvements. By analyzing the problems in the information and material flow that arises at the construction site with a focus on efficiency and minimizing waste.  At the beginning of the thesis, a literature study of scientific reports, articles and fiction in order to have an overview and knowledge of the subject. Results of the report were carried out by mainly most focus on case studies on the construction site, numerous workplace visits and structured interviews. The data was collected mainly through visits to the construction site in order to obtain information through observations and interviews which were a great help. The interviews were conducted at the project manager and supervisor of the project, Hotell Victor. Furthermore more interviews took place with other projects and companies to get understanding how big a problem it is in general.  Several risks were identified on the basis of empirical data, which is raised and described like probable risks occur, and then it is likely that these risks are not exclusive just for AF Gruppen in Gothenburg. The results from the case study indicate, above all that communication between the contractor and supplier could be improved, this would save construction companies time and money. Announcement of the material as arriving until the construction site are integrated for all good and require improvement. Reprogramming, wait and unnecessary movements are few activities that occur.
29

Improvements in Internal Logistics : A Case Study at SSAB Oxelösund - Logistics Development Department

Ghaffari, Faezeh, Mozafari, Arash January 2018 (has links)
Internal logistics is a combined performance of human resources, machines, transportation, and storage system. Thus, different elements and factors are involved in the internal transportation such as human factors and system functions. Moreover, Internal transportation is an important part of production activities because of its close cooperation with production processes. Since the largest portion of the logistics costs is related to transportation, improvements in transportation will lead to a significant increase in profits. The purpose of this thesis is to make improvements in the internal transportation of SSAB. Improvements here means identifying involved wastes in internal transportation, then give recommendations and suggestions to eliminate those wastes. This is a single case study at SSAB Oxelösund. SSAB stands for Svenskt Stål AB formed in 1978 and is well-known because of its special steel products. This company produces steel products for both standard and special orders and uses. All the underproduction plates have to go through a chain of operations to become the finished products. Different operation can be mentioned as cutting, painting, sorting, etc. Material movements in this chain of operations are done with the help of special cassettes and carriers. Cassettes are the main resources intheinternal transportation of SSAB and availability of empty cassettes plays a key role in the whole production process of the company. There are three departments that are involved with internal transportation at SSAB Oxelösund. Four research objectives are designed to cover the purpose of this study. In the following, several interviews and observations are done to collect the qualitative part of data gathering. The quantitative part of data collection is done with exporting data series from company’s database. Theoretical frame work ismainly based on Lean and logistics theories. Analysing the collected data and comparing the results with theoretical frame work lead to identifying the wastes in different areas related to defined research objectives. Different wastes are identified in carriers and drivers’ performances, treatment stations, etc. Therefore, specific recommendations are given based on the identified wastes in order to eliminate those wastes. The recommendations are presented to have faster and optimized material flow. Additionally, areas for further research and an Impact/Effort matrix are provided for future implementations and analysis.
30

Viabilidade econômica e energética do preparo profundo de solo no cultivo da cana-de-açúcar / Economic and energy viability of deep tillage in sugarcane cultivation

Oliveira, Daniela Cristina de 10 October 2017 (has links)
A cana-de-açúcar é a cultura com finalidade energética mais importante do agronegócio brasileiro, por gerar muitos empregos no setor, representar uma parcela significativa do PIB agropecuário e por ser a fonte renovável de energia com maior participação na matriz energética brasileira. O sucesso de seu cultivo depende, dentre outros fatores, da realização do preparo de solo adequado para fornecer às plantas condições favoráveis de desenvolvimento, particularmente do sistema radicular. Em geral, ele é realizado a cada cinco anos e o custo de implantação do canavial, no qual ele se inclui, é alto, representando em torno de 25% desse custo. Os sistemas de preparo de solo comumente utilizados são o convencional e o reduzido, ambos mecanizados. O primeiro tem como característica práticas intensivas de mobilização do solo em camadas mais rasas, enquanto o segundo é composto por número reduzido de operações e máquinas na área e a mobilização do solo pode ser em camadas rasas ou profundas. A escolha pelo sistema de preparo de solo mais econômico e sustentável é complexa por envolver muitas variáveis. Avaliações econômica e energética têm sido uma alternativa eficiente para analisar sistemas de produção agrícola, pois fornecem indicadores financeiros e ambientais para auxiliar na tomada de decisão na adoção do sistema de preparo. Tendo em vista a importância econômica e energética da cana no cenário nacional, a influência do preparo de solo no desenvolvimento da planta e na composição dos custos operacionais, associados à carência de estudos energéticos que avaliem o sistema mecanizado do preparo profundo do solo, este trabalho teve o objetivo de analisar a viabilidade econômica e energética do sistema de preparo de solo profundo no cultivo da cana-de-açúcar em comparação ao sistema convencional. Para tal foi desenvolvido um modelo em planilha eletrônica que auxiliou na determinação dos indicadores econômicos e energéticos de cada sistema de preparo de solo. Os resultados apontaram que o sistema de preparo profundo do solo é viável do ponto de vista econômico e energético, pois apresentou custo operacional de 401,50 R$ ha-1 e demanda de energia de 2,63 GJ ha-1, respectivamente, 30% e 40% inferiores, ao sistema convencional. A análise de sensibilidade evidenciou que a capacidade de campo operacional, a potência do trator e o consumo de combustível foram os fatores de maior impacto na variação dos custos operacionais e na demanda de energia de entrada. / Sugarcane is the most of important energy crop for Brazilian agribusiness, since it propitiates many jobs, it represents a significant share of agricultural GDP and it is the renewable source of energy of higher contribution to the energy matrix. The success of its cropping depends, among other factors, of the appropriate tillage system to provide the plants favorable development conditions, particularly to the root system. Generally, it is carried out on every five years and it accounts around 25% of cropping cost. Soil tillage systems usually adopted are conventional and reduced, both mechanized. The conventional system consists of several operations in the superficial layers, while the reduced one uses less operations and soil mobilization can be in shallow or deep layers. In this latter category, the system of deep soil tillage is included if it is carried out in rows of planting. Economic and sustainable soil preparation system is complex because it involves many variables. Economic and energy assessments have been an efficient alternative to analyze agricultural production systems because it provides financial and environmental indicators for decision making on system adoption. Considering the economic and energy importance of sugarcane in the national scenario, the influence of soil preparation on the development of the plant and the composition of the operational costs, associated to the lack of energy studies that evaluate the mechanized system of deep soil preparation, this study aimed to analyze the economic and energy viability of the deep soil preparation system in sugarcane cultivation compared to the conventional system. For this purpose, a model was developed which assisted in the determination of the economic and energy indicators of each soil preparation system. The results showed that the deep soil preparation system is feasible from an economic and energy point of view, since it presented operational cost of 401.50 R$ ha-1 and energy demand of 2.63 GJ ha-1, respectively, 30% and 40% below the conventional system. Sensitivity analysis showed that the operational field capacity, the power of the tractor, the fuel consumption were the factors presented greater relevance in the variation of operating costs and the demand for input energy.

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