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Dissertations / Theses on the topic 'Warehouse efficiency'
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Salomonsson, Emilie. "Challenges for warehouse efficiency : A case study at a stock point warehouse." Thesis, Högskolan i Gävle, Avdelningen för industriell ekonomi, industridesign och maskinteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-36953.
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Introduction: Improving efficiency through the supply chain has long been strived for by management. Traditional approaches focus on improving efficiency in the supply chain through optimization of a company’s internal activities, where warehouses play an important role. Companies are therefore dealing with the dilemma of how to increase efficiency in their warehouse, yet at the same time reduce operational costs. Current research focuses on strategies to increase efficiency in conventional warehouses by studying design, operations, and planning. Digitalization and lean warehousing are also emerging as important tools for warehouse efficiency. However, alternative warehouse types exist that are less researched. The research aimed therefore to investigate the challenges warehouses with stock point design face. Methods: A qualitative and deductive case study approach was chosen. A literature review was first conducted to find the variables defining warehouse efficiency. Interviews and observations were then performed at the case company to investigate how the variables affect efficiency at the case company. Lastly, the theoretical framework was compared to the findings to find strategies to overcome the challenges. Findings: Efficiency problems can be found in many aspects of the case company´s warehouse. Over time the warehouse has lost its structure, where a lot of reliability for warehouse procedures are placed on the employees and their knowledge about the company and all parts. Because of missing routines for reviewing parts data, changes in generations and parts being revised, are hard to keep track of which causes an effect on efficiency. It also increases the risk of deadstock. Conclusions: In previous research, few studies could be found where researchers tackle the problems that multiple storage building causes on efficiency. By concluding that seven key variables define warehouse efficiency from previous research and applying them to a warehouse with stock point design, the challenges that an alternative warehouse face through the important variables in warehouse efficiency research could be explained. All the variables affect efficiency, yet warehouse design has the biggest impact. Because of limited abilities with hand scanners and missing routines for reviewing parts data, operations, movement, and planning can also be concluded to have a high influence on efficiency. To overcome the challenges, strategies for class-based storage assignment should be applied from the perspective of the storage building limitations. Right conditions for batching and good routines for warehouse procedures and reviewing parts data are also suggested as strategies.
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Fong, Hui Ni Grace. "Improving and maintaining the operational efficiency of a semiconductor equipment manufacturing warehouse." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101336.
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Thesis: M. Eng. in Manufacturing, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 85-86).
The present work addresses an operational inefficiency problem at a semiconductor equipment manufacturing warehouse, Varian Semiconductors Associates and Equipment (VSEA). This problem is important because if unresolved, the warehouse is unable to meet the part delivery time target of 24 hours during the busy period. The downstream effects of the late part delivery are delayed production schedules and in the worst case scenario, a missed shipment to the customer, which is very costly. In order to improve the efficiency of the warehouse so as to consistently deliver parts on time, the picking efficiency needs to be enhanced. Parts are primarily picked from two types of storage locations - GL shelves and Vertical Lift Modules (VLMs). The picking efficiency can be improved by the simultaneous reduction in workload on GL and improvement in the VLM picking efficiency. The first part of this thesis focuses on improving the picking inefficiency at the VLMs by employing a more efficient picking method. From our time study, we find that the pick-and-consolidate (parallel picking) is more efficient than pick-and-pass (sequential picking). The average makespan time savings per order by pick-and-consolidate is 8% (20 minutes). The second part of this paper discusses what is required to maintain a high VLM picking efficiency. New metrics to measure the workload distribution of the VLMs and the average flow time per order are proposed. Three dynamic slotting methods that maintain a balanced workload distribution across the VLMs without the need for periodic review are also examined. The methods are evaluated based on how balanced is the workload distribution across the VLMs and the cost of implementation.
by Hui Ni Grace Fong.
M. Eng. in Manufacturing
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Blom, Amanda, and Sofia Stenman. "Warehouse management – streamlining picking rounds." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-25536.
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In this study we have conducted research on how to optimize inventory management within logistics. The focus in this study is to examine the picking rounds, the reason for this is because it is the most time consuming and expensive part within a warehouse. Is it possible to minimize the handling time to create efficient picking rounds? As a part of the research project AI has been investigated as well. If it is possible with help of AI, create a streamlining of current warehouse logistics. The purpose of this report is to investigate how to minimize the distance in picking rounds for efficient warehouse management. To be able to fulfil the purpose of the report research questions where conducted. The methodology that was chosen at first was traditional data collection. With the help of other studies conducted in this area we started to collect information. To be able to compare this information to the chosen company Care of Carl a case study was performed. A case study on the current situation at Care of Carl, and what the current optimization is based on. With the help of these two methods a result emerged. The result that was conducted by this study is that placement and categorization of products as well as route planning has a significant role when streamlining the picking process and minimizing the picking process. To store items in a warehouse the most suitable option is to use a free item placement, or storage out of sale frequency. But important to acknowledge is that it requires support systems to make this storage possible. When categorizing articles, it is crucial to combine this with a suiting picking method. In the case study, combining ABC categorization with zone picking was a possible solution. In general, it might be a good idea to invest in AI to use the picking position principle. With AI it is possible to analyse more complex data such as customer patterns and if this implementation succeeds it can lead to great advantages within a warehouse and the picking processes. The traveling distance constitutes most of the total picking time, it is important to have a route method that works with how you have chosen to place the items. This study shows that the optimal routing method is the one to use. This study showed that there are a lot of different strategies and methods on the current market. According to the case study Care of Carl can make big savings by changing strategies and methods. The reason why is because they have been reactive when investing in IT support systems. But in general, if a company wants to meet the current increasing requirements according to the globalization and the continuous changes within logistics operations, AI is the next step. The methods that are currently used are not sufficient, with the help of AI there is room for improvements within product allocation and route planning.I denna studie har det undersökts hur man kan optimera lagerhanteringen inom logistik. Fokus har varit att undersöka plockrundorna, då det är den mest tidskrävande och kostsamma delen inom ett lager. Är det möjligt att minimera hanteringstiden och därmed effektivisera plockrundorna? Studien har även varit en del av ett forskningsprojekt där man har undersökt om det med hjälp av AI är möjligt att skapa en effektivisering av lagerhantering. Syftet med denna rapport är att undersöka hur man minimerar avståndet i plockrundorna för att effektivisera lagerhanteringen. För att kunna uppfylla syftet med rapporten utformades det forskningsfrågor kopplat till syftet. Traditionell datainsamling var den metod som användes för att komma i gång med studien. Den teoretiska referensramen som skapades i denna rapport var utifrån andra studier som genomförts inom detta område, men även utifrån att kunna besvara de forskningsfrågor som skapats. Det genomfördes även en fallstudie på företaget Care of Carl, med en nulägesbeskrivning samt en förklaring gällande hur deras nuvarande optimering tagits fram. För att kunna besvara syftet med rapporten och forskningsfrågorna jämfördes den teoretiska referensramen med den fallstudien som genomförts i samband med denna studie. Resultatet som framkom under studien var att placering och kategorisering av produkter såväl som ruttplanering har en avgörande roll gällande effektivisering av plockprocessen i ett lager. Gällande inlagringsmetod är det lämpligast att använda sig av flytande artikelplacering alternativt lagring utifrån försäljningsfrekvens. Vad som är viktigt att nämna är att båda metoder kräver ett stödsystem för att kunna implementeras. Gällande kategorisering av artiklar är det viktigt att kombinera detta med en passande plockmetod. I fallstudien var en möjlig lösning att kombinera ABC-kategorisering med zonplockning. Generellt sätt är AI en framtida värd investering då man kan använda sig av plockpositionsprincipen. AI möjliggör analysering av mer komplexa data som kundmönster och om denna implementering lyckas kan det leda till stora fördelar inom ett lager och för plockprocessen. Det är även viktigt att ha en ruttmetod som fungerar ihop med den placeringsmetod man använt sig av, då gångtiden och gångavståndet är det som utgör det mesta av den totala plocktiden. Denna studie visar att den optimala ruttmetoden är den som bör användas, och detta kräver en investering i ett stödsystem. Denna studie visade att det för tillfället finns många olika strategier och metoder på marknaden idag. Enligt fallstudien kan Care of Carl göra stora besparingar bara genom att ändra sina strategier och metoder. Orsaken är att de har varit reaktiva vid investeringav IT-stödsystem. Generellt sätt, om ett företag vill uppfylla de ökande kraven som finns till följd av globaliseringen och de kontinuerliga förändringarna inom logistikverksamheten, är AI nästa steg att ta. Metoderna som för närvarande används är inte tillräckliga och med hjälp av AI finns det möjlighet för förbättringar inom produktallokering och ruttplanering.
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van, Hooff Jonathan, and Oscar Tegni. "Development of Supply Chain : Information System Integration at Consignment Warehouse for Improved Efficiency." Thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-90520.
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Sandvik Rock Tools is operating in a highly competitive market. This requires them to constantly improve the efficiency of their organization, in order for them to maintain their position as market leaders, both in a short-term and a long-term perspective. Sandvik Rock Tools is currently working on developing and further improving their supply chain. The supply chain is a key organizational function and improvements of the supply chain aim to yield benefits like lowered total costs and better utilized inventory levels. The purpose of our work has been to develop the supply chain between Sandvik’s in-market warehouse and their customer site at Dannemora. The main focus of this thesis has been to enable automatic data collection and to lower the stock levels at the customer site in Dannemora. This would be accomplished by improving the information flow between the two entities in the observed supply chain and by enabling real-time inventory information, easily accessible to the warehouse manager. A barcode system was implemented in the warehouse at the Dannemora customer site and was integrated with warehouse management software that was developed by the authors. The implemented barcode system and the warehouse management software were used at the Dannemora customer site for a period of two months. The effects of the implemented barcode system working in combination with the warehouse management software were observed in several operational areas after implementation, and the results were positive and beneficial. Firstly, the barcode system and warehouse management software simplified the warehouse manager’s decision process, by providing easy access to necessary warehouse management information, like realtime inventory information. Secondly, it made the day-to-day work routine of the warehouse manager easier, this being the case because the barcode system that had been implemented had digitalized and automated many tasks that had previously been performed manually by warehouse manager. An excellent example would be the simplified process for order placement and stocktaking. Thirdly, it improved the information flow between the Dannemora customer site and Sandvik’s in-market warehouse in Sandviken, thereby improving the overall effectiveness of the entire supply chain, through shared information. The barcode implementation successfully lowered inventory levels by six percent on average.
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Toor, Paramveer Singh. "Improving operational efficiency of a semiconductor equipment manufacturing warehouse through strategic allocation of parts." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101477.
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Thesis: M. Eng. in Manufacturing, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (page 75).
The work addresses the operational inefficiency problem in a semiconductor equipment manufacturing warehouse of Applied Material's Varian Semiconductor Business Unit. At Varian, the target part delivery time from the warehouse to the production floor is 24 hours. However, during busy periods, parts are not delivered on time. Late part delivery from the warehouse to the production floor could delay the machine laydown date, which in turn could result in late or missed shipment of tools to the customers, which can be very costly. To improve the efficiency and the reliability of the warehouse, picking efficiency is to be improved. Parts from the warehouse are picked from three picking locations- Vertical Lift Modules (VLMs), GL, and RK. VLMs are automated machines, while GL and RK are manual picking zones. Picking an order from GL takes the most amount of time. The overall picking efficiency at the warehouse can be improved by partially shifting the workload from GL to the VLMs, and by further improving the picking efficiency at the VLMs. The workload from GL to the VLMs is shifted by transferring fast moving parts from GL to the VLMs. The picking efficiency of the VLMs is improved by balancing the workload of all five VLM pods, and by employing a more efficient 'pick-and-consolidate' picking strategy. The workload at GL is decreased by 25% and the workload at VLMs is increased by 13%. Despite the increase in workload at VLMs, 23% time savings could be achieved by balancing the utilization of all five VLM pods. Additional time savings of 20 minutes per order (8%) could be achieved by using 'pick-and-consolidate' picking strategy over 'pick-and-pass' picking strategy.
by Paramveer Singh Toor.
M. Eng. in Manufacturing
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Racca, Stephen Douglas. "Improving operational efficiency of a semiconductor equipment manufacturing warehouse through effective utilization of Vertical Lift Modules." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101335.
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Thesis: M. Eng. in Manufacturing, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 59-60).
This thesis deals with improving the operational efficiency of automated part storage devices, in this case Vertical Lift Modules (VLM). This was accomplished by using dynamic slotting to maximize and maintain high material throughput, eliminating the need for periodic reslotting. Multiple VLMs can be used in parallel picking operations to improve material throughput. Common industry practice is to periodically reslot items once an unbalanced workload is obvious. This thesis investigates a method to avoid periodic reslotting by using incoming parts as a means to maintain a balanced workload amongst VLMs. Three different part allocation strategies are compared, namely Randomization, Snake and Order Grouping to determine their effectiveness and respective feasibility. The three strategies are then crafted into logical systems that could be used to strategically place received parts and eliminate the need for periodic reslotting. The Snake method was found to be the most well suited for this particular situation due to the small order sizes. This method provides a 35% savings in pick time, which is equivalent to approximately 733 hours annually.
by Stephen Douglas Racca.
M. Eng. in Manufacturing
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Markén, Camilla, and Emma Hultqvist. "Improving the internal efficiency at IKEA After Sales focusing on the development of a warehouse management system." Thesis, Uppsala universitet, Industriell teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-329083.
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A warehouse management system shall handle warehousing operations with the aim of gaining control over the company's storage capacity and inventory management. It should support functions such as goods receiving, warehousing, order receiving and orderpicking. In order for a warehouse management system to function optimally, it must be designed for the company's operations. The purpose of this thesis work is to analyze the current warehouse management system and associated processes at IKEA After Sales. By analyzing the current situation, the improvement work will result in a development of current system or system replacement. In addition, an implementation plan will be presented for the chosen solution. The systems that have been analyzed are M3 and Astro. The research work began with a visit to IKEA After Sales where observations and interviews were conducted. The focus was on mapping how operations work today and where there is potential for a warehouse management system. A list of requirements was then presented to describe what functions a system should contain. The requirement list was discussed with responsible IT-workers for both systems. The survey showed that a lot of work is done manually and is dependent on competent employees. The research work resulted in an implementation of untapped functions in the already used system M3. The implementation plan focuses on Warehouse Mobility, inventory function and Wave Picking features with associated routines. The routines for how the business should work was designed to facilitate the workload after implementing the above functions.Ett lagersystem ska hantera lagerverksamheten med syftet att skapa kontroll över företagets lagringskapacitet och lagerhantering. Systemet bör stödja funktioner som godsmottagning, lagerläggning, ordermottagning och plockorder. För att ett lagersystem ska fungera optimalt bör det vara utformat efter företagets verksamhet. Syftet med examensarbetet är att analysera det nuvarande lagersystemet med tillhörande processer på IKEA After Sales. Genom analys av nuläget ska förbättringsarbetet resultera i en förbättring av nuvarande lagersystem eller förslag på byte av system. Vidare ska en implementeringsplan presenteras för det valda lösningsförslaget. De system som har analyserats är M3 och Astro. Examensarbetet inleddes med ett besök på IKEA After Sales där observationer och intervjuer genomfördes. Fokus låg på att kartlägga hur verksamheten arbetar idag och var outnyttjad potential för ett lagersystem finns. En kravlista framställdes för att beskriva vilka funktioner som bör finnas i ett lagersystem. Kravlistan diskuterades med respektive IT-ansvarig för systemen. Kartläggningen visade att mycket arbete sker manuellt och är beroende av kompetent personal. Resultat av examensarbetet är förslag på en implementering av outnyttjade funktioner i det redan använda systemet M3. Implementeringsplanen fokuserar på funktionerna Warehouse Mobility, stöd för inventering och Wave Picking med tillhörande rutiner. Rutinerna för hur verksamheten bör arbeta har utformats för att underlätta arbetsmomenten efter att ovanstående funktioner har implementerats.
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Khodr, Nino. "Strengthening Efficiency and Safety in Forklift Operations through Autobiographical Design." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-296186.
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Forklift vehicles used for moving pallets and boxes in warehouses, have recently been integrated with Internet of Things (IoT) technology, in effect making forklifts networked and in parts controllable from afar. Human operators now carry out tasks according to instructions displayed on the screen of the IoT-forklift instead of just maneuvering around and executing tasks as they see fit. Through an autobiographical design process, hazardous situations arising because of limitations at the interface of the IoT-forklifts were revealed. To address these hazardous situations, we propose changing the interface of the forklift to better monitor the pick-up and dropping of packages. Changes to the digitally-enabled interface was done through the implementation of modalities. In short three modalities was considered, tactile, visual and auditive ones. While the tactile modality was not deemed to be feasible, the visual and auditive modalities was prototyped and evaluated through an Wizard of Oz method. Colored LED light strips showed to improve the handling, locating, selecting and moving the correct goods within the warehouse while keeping both operators and items safe. Further improvements to the digitally-enabled infrastructure in the warehouse that can optimize the routes to and from the pickup were devised. Cameras, sensors and lasers installed on advantageous places within the warehouse and on the forklift will help keeping track on both the forklift operators and the items during pick - and drop operations. As a result the system will have an awareness of its environment were both efficiency and safety will be further improved.Gaffeltruckar som används for att flytta pallar och lådor i lager har nyligen integrerats med IoT-teknologin (Internet of Things), vilket gör gaffeltruckar i nätverk och i delar kontrollerbara långt ifrån. Mänskliga operatörer utför nu uppgifter enligt instruktionerna som visas på IoT-gaffeltruckens skärm istället för att bara manövrera runt och utföra uppgifter som de anser lämpligt. Genom en självbiografisk designprocess avslöjades farliga situationer som uppstod på grund av begränsningar vid gränssnittet mellan IoT-gaffeltruckarna. För att hantera dessa farliga situationer föreslår vi att man ändrar gaffeltruckens gränssnitt för att bättre övervaka hämtning och släppande av paket. Ändringar av det digitalt aktiverade gränssnittet gjordes genom implementering av modaliteter. Kort sagt övervägdes tre metoder, taktila, visuella och auditiva. Även om den taktila modaliteten inte ansågs vara genomförbar prototyperades och utvärderades de visuella och auditiva metoderna genom en Wizard of Oz-metod. Färgade LED-ljusremsor visade sig förbättra hanteringen, lokaliseringen, valet och flyttandet av de rätta varorna inom lagret och samtidigt hålla både operatörer och föremål säkra. Ytterligare förbättringar av den digitalt aktiverade infrastrukturen i lagret som kan optimera rutterna till och från upphämtningen planerades. Kameror, sensorer och lasrar installerade på fördelaktiga platser i lagret och på gaffeltrucken hjälper till att hålla koll på både gaffeltruckoperatörema och föremålen under plock - och släppoperationer. Som ett resultat kommer systemet att känna till sin miljö där både effektivitet och säkerhet kommer att förbättras ytterligare.
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SÖDERBÄRG, KARL. "Industry 4.0 to enhance lean resource efficiency." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299625.
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This paper is a practical and empirical investigation into the relationship and overlap between the two industrial paradigms of Lean Management and Industry 4.0. This is accomplished with an in-depth case study of a goods receipt to identify Lean wastes and accompanied by a discussion on how these wastes can be eliminated by enhancing the processes and material flows with Industry 4.0 technologies. It was found that efforts to enhance a process with Industry 4.0 Technologies should be preceded by ensuring that the process can be performed in a standardized manner. After that the study recommends improved methods of data collection which enables the effective implementation of other supporting Industry 4.0 Technologies.Denna uppsats är en praktisk och empirisk utredning av relationen och samspelet mellan de två industriella paradigmen Lean Management och Industri 4.0. Till grund för det för det ligger en utförlig fallstudie av en godsmottagning för att identifiera Lean slöserier och en tillhörande diskussion om hur dessa slöserier kan elimineras genom att förbättra arbetsprocesser och materialflöden med Industri 4.0 och tillhörande teknologier. Ur det uppdagades att åtgärder för göra processer mer effektiva med dessa Industri 4.0 teknologier bör föregås av att processen kan utföras på ett standardiserat vis. När det är säkerställt så är det denna studies rekommendation att fokusera på metoder och verktyg för insamling av data vilket blir den grund som möjliggör implementering av behjälpliga och automatiserande Industri 4.0 teknologier.
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Söderbärg, Karl. "Industry 4.0 to enhance lean resource efficiency." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-301241.
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This paper is a practical and empirical investigation into the relationship and overlap between the two industrial paradigms of Lean Management and Industry 4.0. This is accomplished with an in-depth case study of a goods receipt to identify Lean wastes and accompanied by a discussion on how these wastes can be eliminated by enhancing the processes and material flows with Industry 4.0 technologies. It was found that efforts to enhance a process with Industry 4.0 Technologies should be preceded by ensuring that the process can be performed in a standardized manner. After that the study recommends improved methods of data collection which enables the effective implementation of other supporting Industry 4.0 Technologies.Denna uppsats är en praktisk och empirisk utredning av relationen och samspelet mellan de två industriella paradigmen Lean Management och Industri 4.0. Till grund för det för det ligger en utförlig fallstudie av en godsmottagning för att identifiera Lean slöserier och en tillhörande diskussion om hur dessa slöserier kan elimineras genom att förbättra arbetsprocesser och materialflöden med Industri 4.0 och tillhörande teknologier. Ur det uppdagades att åtgärder för göra processer mer effektiva med dessa Industri 4.0 teknologier bör föregås av att processen kan utföras på ett standardiserat vis. När det är säkerställt så är det denna studies rekommendation att fokusera på metoder och verktyg för insamling av data vilket blir den grund som möjliggör implementering av behjälpliga och automatiserande Industri 4.0 teknologier.
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Hellström, Elin, and Fredrika Borgmalm. "Lagerställesrationalisering hos Midelfart Sonesson AB." Thesis, Södertörn University College, School of Business Studies, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-1554.
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Företag: Midelfart Sonesson AB
Syfte: Studien skulle ge en bild av vilka kriterier som är betydelsefulla för företag vid rationalisering av lagerställen. Den skulle dessutom ge en bild av vilka tänkbara ekonomiska konsekvenser som kan följa efter en rationalisering. Genom en fallstudie av ett typföretag och genom kompletterande intervjuer med kunniga inom logistik och företagsekonomi skulle författarna undersöka vilka kriterier som företagen lägger mest vikt på när de ska starta ett så stort projekt som lagerställesrationalisering, samt förstå vad kostnadsbesparingen kan bli.
Metod: En studie av företaget Midelfart Sonesson AB har utförts. Primär- och sekundärdata har samlats in genom personliga intervjuer, litteratur, rapporter, och elektroniska källor.
Teori: Teorin består av nio olika avsnitt som kan tillämpas på ämnet i uppsatsen. Teorin används för att förstå företagets uppbyggnad, organisation och dess handlande. Det ger en förståelse av lagerhållning och lagerställesrationalisering.
Empiri: I empirin beskrivs företagets situation idag. Förslag från konsulten tas upp, angående den förändring och det val som de står inför. Material som inkommit genom intervjuer belyses även i empirin.
Slutsats: Kostnadseffektivitet med bibehållen kundservice är de viktigaste kriterierna. Stora kostnadsbesparingar kan göras vid lagerställesrationalisering.
Company: Midelfart Sonesson AB
Purpose: The essay should give a picture of which criteria are important to companies when rationalizing their warehouse places. It would also illustrate what the possible economic consequences could be after a rationalization. A case study of a typical company and in addition, interviews with experts in the areas of logistics and business administration should help the authors investigate which criteria the companies emphasize, when they start such a large project as warehouse place rationalizing, and also understand the cost effect.
Methodology: A study of the company Midelfart Sonesson AB has been done. Primary- and secondary data has been gathered through personal interviews, literature, reports and electronic sources.
Theoretical perspective: The theory consists of nine different sections that can be applied to the subject of this essay. The theory is used to understand a company’s build-up, organization and its action. It gives a comprehension of stock holding and warehouse place rationalization.
Empirical foundation: This is where the company’s situation of today is described. The consultant’s recommendations, concerning the transformation and the choice that has to be made, are described. Information received through interviews is also illustrated in the empirical foundation.
Conclusion: Cost efficiency with maintained customer service is the most important criteria. Large cost savings can be made through warehouse place rationalizing.
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Iglesias, Estellés Javier. "Study of the ventilation system in a warehouse and a cooking school : Impact of the use of a heat exchanger system and a more optimised operating schedule." Thesis, Högskolan i Gävle, Energisystem, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-26907.
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The motivation of this project is found on the past trend of growing greenhouse gases emissions and, also growing, energy use over the world that still remains. This trend overlaps with a more recent increase in the awareness regarding the effects of human activities towards the Earth ecosystems. Thus, the upgrade of the already-in-use systems is necessary to move towards greener and more modern technologies that permit continue with the economic growth while building more sustainable societies. Thereby, the research focuses on the improvement of the ventilation system of a warehouse building and a cooking school located in the same plot, in an industrial area in Gävle, Sweden. The current system conditions, even consisting in some cases in recirculating air handling units, doesn’t permit the utilisation of the waste heat by bringing it back to the system. The strategy used during the project follows a case study scheme: looking the system, understanding it in a complete way and designing the proper solution that fulfils the requirements. The study was approached as an energy audit: with several meetings with the company, collecting airflows data with the thermo-anemometer device, sketching the required building drawings and designing the optimal solution for the company. Finally, the project resulted in the selection of the proper air handling unit, equipped with a heat recovery system, and the design of its ventilation duct system that permit a heat energy savings derived of the heat demand used to heat the makeup air of about 67 %. Furthermore, the occupancy study helped design the new scheduling for the ventilation periods that reduce the electricity demand of the ventilation system by 30 %. Thus, was obtained a significant energy use reduction that results in a sizeable energy cost saving.
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Grip, Katarina, and Jennifer Pålsson. "Hur lagerhanteringssystem och artikelidentifiering kan bidra till logistisk effektivitet : En fallstudie på Nefab i Runemo." Thesis, University of Gävle, Ämnesavdelningen för industriell ekonomi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-4625.
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Warehouses are a key aspect of modern supply chains and play a vital role in the success or failure of businesses today. Figures from the USA indicate that the capital- and operating costs of warehouses represent about 22 % of a company’s logistics costs while figures from Europe indicate 25 % (Baker & Canessa, 2009). Because warehousing is such an important function within a company, the authors chose to focus on this in their thesis. The purpose of this thesis has been to examine the significance of a Warehouse Management System (WMS) and item identification with attention to logistic efficiency. With this as a starting point, the thesis also intends to examine the needs and possibilities with a WMS and some sort of item identification at a specific company and also present suggestions of how to move forward with this type of work.
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Mohammad, Fedek Kawthar, and Anna Johansson. "Effektivisering av inleveransprocesser på lager : Med Human Lean aspekter." Thesis, Högskolan i Gävle, Avdelningen för industriell ekonomi, industridesign och maskinteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-30131.
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Logistics is an integral component in making the production process more efficient in companies. An important concept in logistics is lead time, the time it takes for a product to go through the process from inbound and outbound to the customer. A normal logistical process comprises the initial receival of goods, controls upon arrival and further quality controls carried out before the product ends up in the storage. The delivery process is a central process with many sub-processes including varying working methods and routines that can result in permeating inefficiencies in the company if they aren’t done properly. The purpose of the study is to identify causes of inefficiency that might cause extended lead times and reduced productivity in the delivery process. This is achieved by studying the internal workflow and routines of Volkswagen Parts Logistics delivery process. This study’s based on a case and the data is gathered by semi-structured interviews and observations at Volkswagen Parts Logistics. Thereafter the results are analysed through literature and scientific articles. The study first identifies one cause of inefficiency through factors such as simplification, synchronization, communication and integration. To identify the root-cause, a root-cause analysis has been used on these factors, which are then compiled into a cause and effect diagram and finally six factors have been explained. From the analysis and discussion of the six factors, four improvement suggestions have been submitted to Volkswagen Parts Logistics. The suggestions included education & training, standardized working methods, understanding the whole process and cooperation between groups. The study presents a scientific gap regarding the efficiency improvement of lead time with Human Lean aspect with a focus on the delivery process. The study contributes to the gap through the six factors and improvement suggestions based on analysis and discussion.Logistik har blivit allt viktigare för att effektivisera produktionen i företag. Ett viktigt begrepp inom logistik är ledtid, i den här studien innebär ledtid tiden det tar för en reservdel inleverans till utleverans vidare mot kund. En väsentlig del inom logistik är inleveransprocessen för inkommande gods som går igenom godsmottagning, ankomstkontroll och kvalitetskontroll för att sedan hamna på lagerhyllan. Inleveransprocessen är en central process med många delprocesser och varierande arbetssätt samt rutiner som vid brister kan medföra en genomsyrande ineffektivitet i företaget. När avvikelser uppstår kan det medföra en förlängning av ledtiden vilket påverkar resten av processen och framförallt utleveransen till kunden. Studiens syfte är att identifiera orsaker till ineffektivitet som kan leda till förlängda ledtider och minskad produktivitet i inleveransprocessen. Det görs genom att studera arbetssätt och rutiner i inleveransprocessen. För att utveckla kunskap rörande faktorer som påverkar inleveransprocessen är en fallstudie som grund med genomförda semistrukturerade intervjuer och observationer genomförts på Volkswagen Parts Logistics. Resultat har analyserats med hjälp av litteratur och vetenskapliga artiklar från forskningsområdet. I studien identifieras först orsaken till ineffektivitet genom faktorer som förenkling, synkronisering, kommunikation och integration. För att identifiera rotorsaken till ineffektivitet har en rotorsaksanalys genomförts på dessa faktorer som sedan sammanställts i en orsakverkan-diagram och slutligen har sex stycken faktorer presenterats. Utifrån analys och diskussion för de sex faktorerna framtogs fyra stycken förbättringsförslag till fallföretaget. Förbättringsförslagen innefattade utbildning & upplärning, standardiserade arbetssätt, förståelse för hela processen och samarbete mellan grupper. I studien framförs ett vetenskapligt gap gällande effektivisering av ledtid med Human Lean aspekt med avgränsning till inleveransprocessen. Studien bidrar till detta gap genom de sex framtagna faktorerna samt formulerade förbättringsförslag baserat på analys och diskussion.
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Hammerin, Karl, and Adrian Werther. "Beslutstödsmodell : För ökad effektivitet i lagermiljöer." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Maskinteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-36517.
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The globalized world has increased people’s awareness, which has resulted in a higher demand for better quality as well as shorter led times, without increasing the selling price. The fact that companies are actively working with streamlining processes of the existing business can therefore be seen as crucial for its future existence. In this study, a decision support model for the initial part of streamlining projects for warehouses has been developed. The model is based on key theories and methods of efficiency and warehouse layouts. This constitutes the theoretical foundation, for which the six areas of the model were designed. The model is based on a process- and rating structure, in which the six areas were broken down to 12 matrices and 1 summary. In each matrix, the solution methods are rated based on their individual properties against crucial parameters. As support for the model, complementary questions for each area have been developed, to give the user good opportunities to gather necessary information and data. By answering the questions and studying the matrices, the user has a good foundation to select the alternatives that fits the company’s needs. By doing this, the user will be able in a timely manner to identify the most relevant opportunities, and thus also discard those who do not possess the requested features or properties. This study has resulted in a model whose strength lies in its ability to allow companies, at an earlier stage, to allocate resources to the solutions that are relevant and therefore should be examined more closely. This based on the company's situation, goals and needs.
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Huldin, Jessica. "Effektivisering av interna processer : En tillämpning av offensiv kvalitetsutveckling på Astrid Lindgrens Värld." Thesis, Uppsala universitet, Institutionen för samhällsbyggnad och industriell teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413828.
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Studien har genomförts på Astrid Lindgrens Värld som är en nöjespark som vill göra sagor till verklighet och är ett turistmål för människor världen över. Organisationen består av cirka 60 helårsanställda och cirka 500 anställda under sommarsäsong. Fokus för arbetet har varit den interna lagerprocessen på organisationen som innebär det arbete som sker från att beställingsbehov upptäckts tills varor är mottagna. Den interna lagerprocessen har sin utgångspunkt i det centrallager som finns på organisationen och har sedan koppling till sex olika avdelningar inom organisationen. Inom den interna lagerprocessen prioriterades avdelningen butik för att studera hur den interna lagerprocessen kan förbättras i relation till butik. Den interna lagerprocessen kopplat till området butik skapar svårigheter i att veta hur mycket och vad som behöver beställas samt att varor missas i beställningarna. Processen upplevs också vara ineffektiv och tidskrävande. Syftet med studien är att identifiera ett förbättringsförslag som kan skapa en effektivisering och förenkling av arbetet utifrån butiksperspektiv kopplat till den interna lagerprocessen. Studien tar sin utgångspunkt i frågeställningarna (1) Hur ser den interna lagerprocessen ut idag? (2) Vad upplevs problematiskt inom processen? (3) Hur kan den interna lagerprocessen förbättras med hjälp av offensiv kvalitetsutveckling? Det teoretiska ramverket för arbetet tar sin grund i offensiv kvalitetsutveckling med tillhörande värderingar, verktyg och arbetssätt med fokus på Lean. Ramverket presenterar också teorier om organisationsförändring, ansvar samt kommunikation. För att besvara uppställda frågeställningar utgör studien en kvalitativ ansats där datainsamlingsmetoden baseras på intervjuer, fokusgrupper, möten och dokumentstudier. För att analysera, systematisera och skapa mening av insamlade data har verktyg inom offensiv kvalitetsutveckling använts. Resultatet visar på (1) det finns ett gemensamt arbetssätt för den interna lagerprocessen, däremot finns det tre olika sätt att arbeta med processen beroende på om det är en planerad beställning eller akutbeställning. Akutbeställningarna anses som onödiga arbetsmoment som helst önskas minimeras. (2) Problematiken som identifierats grundar sig på medarbetare och chefers upplevelser, där följande grupperad problematik identifierades; tidskrävande arbete, ostrukturerat arbete, högt lagersaldo, förbättringsförslag missas, bristande kommunikation samt att nya rutiner inte efterlevs. (3) Förbättringar som har identifierats är; implementering av 5S, processägare, dragande system, ”Lean-tavla” samt kommunikationsplan. Det förbättringsförslag som bäst svarar upp mot studiens syfte är att implementera 5S och valdes därför vidare för en implementeringsplan. Däremot är det viktigt vid en eventuell implementering av 5S att den integreras med förbättringsförslaget kommunikationsplan för att säkerställa att den nya rutinen kommuniceras ut korrekt och efterlevs.The present study was conducted at Astrid Lindgren’s Värld (ALV), an amusement park and popular tourist attraction in southern Sweden. This study focuses on the park’s internal warehousing processes. The present study focuses on the warehousing process in one of 6 branches, namely that which serves the shops in the park. The aim of this paper was to investigate how the internal warehousing processes can be made more efficient and design a plan of action to remedy the identified issues. The current practices create problems regarding orders, more specifically what needs to be ordered, how much, and items missing from deliveries. Employees also perceive the process to be inefficient and time consuming. The study is based on three questions: (1) what is the current internal warehousing process? (2) What issues can be identified with the current process? (3) How could the internal warehousing process be improved using the theory of total quality management? The study uses total quality management strategies, mainly Lean manufacturing as a theoretical framework together with data collected from interviews and focus groups. The results reveal that (1) there is a common work process in the warehouse at large, however, 3 different approaches are employed depending on whether the order is planned or urgent. Unplanned, urgent orders are seen as unnecessary and should be reduced. (2) Employees and managers identify the process’ main issues to be: time consuming work, unstructured work, an excessive amount of items in the warehouse, suggestions for improvements go unheard, communication issues, and new routine non-conformity. (3) In conclusion, the study recommends five different improvement strategies for the efficiency of the internal processes: implementation of 5S, process owner, pull system, Lean board and a communication-plan. 5S best corresponds to the identified issues at ALV and was therefore chosen for implementation. However, it is key to implement it in tandem with a communications plan in order to ensure proper distribution of information and conformity with new routines.
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Mardix, Ido. "Throughout efficiency analysis of the mobot-carousel storage system." Thesis, Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/24233.
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Pudleiner, David Burl. "Using uncertainty and sensitivity analysis to inform the design of net-zero energy vaccine warehouses." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/52232.
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The vaccine cold chain is an integral part of the process of storing and distributing vaccines prior to administration. A key component of this cold chain for developing countries is the primary vaccine storage warehouse. As the starting point for the distribution of vaccines throughout the country, these buildings have a significant amount of refrigerated space and therefore consume large amounts of energy. Therefore, this thesis focuses on analyzing the relative importance of parameters for the design of an energy efficient primary vaccine storage warehouse with the end goal of achieving Net-Zero Energy operation. A total of 31 architectural design parameters, such as roof insulation U-Value and external wall thermal mass, along with 14 building control parameters, including evaporator coil defrost termination and thermostat set points, are examined. The analysis is conducted across five locations in the developing world with significant variations in climate conditions: Buenos Aires, Argentina; Tunis, Tunisia; Asuncion, Paraguay; Mombasa, Kenya; and Bangkok, Thailand. Variations in the parameters are examined through the implementation of a Monte Carlo-based global uncertainty and sensitivity analysis to a case study building layout. A regression-based sensitivity analysis is used to analyze both the main effects of each parameter as well as the interactions between parameter pairs. The results of this research indicate that for all climates examined, the building control parameters have a larger relative importance than the architectural design parameters in determining the warehouse energy consumption. This is due to the dominance of the most influential building control parameter examined, the Chilled Storage evaporator fan control strategy. The importance of building control parameters across all climates examined emphasizes the need for an integrated design method to ensure the delivery of an energy efficient primary vaccine warehouse.
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Guenov, Marin Dimitrov. "An investigation into efficient multiple command order picking in high bay narrow aisle warehouses." Thesis, Edinburgh Napier University, 1990. http://researchrepository.napier.ac.uk/Output/9235.
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With the increasing tempo of business, order picking efficiency becomes of increasing importance. The aim of this research is to find ways of increasing order picking efficiency by decreasing travel time of the picking cycle. Finding the optimal (shortest) order picking tour can be equated to the task of finding a solution to the Travelling Salesman Problem (TSP). This is notoriously difficult to solve in reasonable time when conventional computers are used. A number of heuristic algorithms have been developed for solving the TSP, some of these have been specially adapted for multiple command order picking. In this previous work the stacker crane's shuttle was assumed to travel with constant velocities in the horizontal and vertical directions. In this research it is shown that this assumption leads to creating suboptimal tours. The contribution of the error is analytically derived and its magnitude estimated by a simulation experiment. In previous work it has been shown that the shape of the zones in class based storage affects the travel time for single and dual command order picking. In this research, for the first time, the interaction between class based storage and multiple command order picking is investigated. Three types of zone configurations are modelled and then investigated using simulation in a factorial experiment. The results from the experiment indicate that the zone shape does affect the optimal solution. The new zone configurations are tested in a case study against existing configurations in a distribution warehouse of Volkswagen - Audi (VAG-UK). This showed that overall improvement in travel time of the new configurations was significant. Computer simulation was used to estimate the individual contribution from zoning and tour construction.
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Johnson, Andrew. "Methods in productivity and efficiency analysis with applications to warehousing." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/29400.
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Thesis (Ph.D)--Industrial and Systems Engineering, Georgia Institute of Technology, 2006.McGinnis, Leon - Committee Chair, Griffin, Paul - Committee Member, Hackman, Steve - Committee Member, Parsons, Len - Committee Member, Sharp, Gunter - Committee Member. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Ferreira, Cornél. "A data warehouse structure design methodology to support the efficient and effective analysis of online resource usage data." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1016072.
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The use of electronic services results in the generation of vast amounts of Online Resource Usage (ORU) data. ORU data typically consists of user login, printing and executed process information. The structure of this type of data restricts the ability of decision makers to effectively and efficiently analyse ORU data. A data warehouse (DW) structure is required which satisfies an organisation’s information requirements. In order to design a DW structure a methodology is needed to provide a design template according to acknowledged practices. The aim of this research was to primarily propose a methodology specifically for the design of a DW structure to support the efficient and effective analysis of ORU data. A variety of relevant DW structure design methodologies were investigated and a number of limitations were identified. These methodologies do not provide methodological support for metadata documentation, physical design and implementation. The most comprehensive methodology identified in the investigation was modified and the Adapted Triple-Driven DW Structure Design Methodology (ATDM) was proposed. The ATDM was successfully applied to the information and communication technology services (ICTS) department of the Nelson Mandela Metropolitan University as the case study for this research. The proposed ATDM consists of different phases which include a requirements analysis phase that was adapted from the identified comprehensive methodology. A physical design and an implementation phase were included in the ATDM. The ATDM was successfully applied to the ICTS case study as a proof of concept. The application of the ATDM to ICTS resulted in the generation and documentation of semantic and technical metadata which describes the DW structure derived from the application of the ATDM at a logical and physical level respectively. The implementation phase was applied using the Microsoft SQL Server integrated tool to obtain an implemented DW structure for ICTS that is described by technical metadata at an implementation level. This research has shown that the ATDM can be successfully applied to obtain an effective and efficient DW structure for analysing ORU data. The ATDM provides guidelines to develop a DW structure for ORU data and future research includes the generalisation of the ATDM to accommodate various domains and different data types.
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Calin, Beatrice Andreea. "Manufacturing Analytics Dashboard: analisi efficienza ed efficacia dei processi produttivi tramite indicatore OEE basata su un MES Data Warehouse." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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La tesi descrive il progetto volto a definire una dashboard che analizza e visualizza visivamente le prestazioni, in particolare l'efficienza e l'efficacia dei processi produttivi, di una piccola impresa emiliano-romagnola, Mollificio Padano srl. Nella prima parte si presentano i concetti teorici utili per la definizione di un cruscotto aziendale, in particolare il concetto di Industria4.0, dei sistemi MES, di KPI (Key Performance Indicator) ed infine di OEE (Overall Equipment Effectiveness) . Inoltre si descrivono gli obiettivi e l'architettura utilizzata. La seconda parte invece tratta della realizzazione della dashboard e la discussione dei risultati ottenuti tramite l'analisi dei dati concludendo con una riflessione riguardo agli sviluppi futuri del progetto.
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Chen, Songting. "Efficient incremental view maintenance for data warehousing." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-122005-193617/.
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Dissertation (Ph.D.)--Worcester Polytechnic Institute.Keywords: View Matching; View Maintenance; Materialized View; Data Warehouse; Information Integration. Includes bibliographical references. (p.206-215)
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BILICH, PAUL. "A more efficient supply chain through categorization." Thesis, KTH, Industriell Management, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-159015.
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I dagens samhälle är det oerhört viktigt att hitta nya sätt att kunna förbättra sitt företag på och genom förbättringar öka lönsamheten. Ett förbättringsområde är företagets försörjningskedja som kan göras bättre genom effektivisering och att se över försörjningskedjans design vilket kan leda till ökad konkurrenskraft. Effektivisering av försörjningskedjan kan bland annat åstadkommas genom att införa kategoriseringsmodeller för att strukturera, prioritera och använda försörjningskedjans resurser optimalt. Målet med examensarbetet är att visa vad användandet av olika kategoriseringsmodeller kan bidra med, hur dessa modeller fungerar i verkligheten och hur de kan användas för att nå optimalt resultat. Fokusen för examensarbetet ligger på kategorisering när det kommer till företagets försörjningskedja och hur kategoriseringen av produkter och leverantörer kan påverka olika delar inom försörjningskedjan som lager, inköp, produkt/leverantör styrning, relationer och strategier. Uppdragsgivaren för detta examensarbete är Cykloteket som ska förändra och effektivisera deras försörjningskedja. Genom att bland annat införa ett centrallager istället för butikslager undersöks möjligheten att strukturera verksamheten för att förtydliga dagliga uppgifter som rör försörjningskedjan. Resultatet från examensarbetet tar upp lämpliga modeller för kategorisering, vad kategorisering bidrar med, rekommendationer hur produkter/ leverantörer bör klassificeras för en tydlig kategorisering och diskuterar vad som kan generaliseras från studien.In today's society, it is extremely important to find new ways for companies to improve their businesses and in that way increase profitability. One area for improvement is the company's supply chain that can be improved by streamlining and reviewing the supply chain design which can lead to increased competiveness. Streamlining the supply chain can be achieved by introducing categorization models to structure, prioritize and to use supply chain resources optimally. The aim of the thesis is to show what the usage of categorization models can contribute with, how these models work in reality and how they can be used to achieve optimal results. The focus of the thesis is the categorization when it comes to the company's supply chain and how the categorization of products/ suppliers can affect different parts in the supply chain such as inventory, purchasing, product / supplier management, relationships and strategies. The commissioner for this thesis is Cykloteket they are in the process of modifying and streamlining their supply chain. For instance they will introduce a central warehouse instead of local warehouses and examine the possibility of structuring the business to clarify the daily tasks related to the supply chain. The result of the thesis addresses the appropriate models for categorization, what categorization contributes with, recommendations how products / suppliers should be classified for a distinct categorization and discusses what can be generalized from the study.
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Roatis, Alexandra. "Efficient Querying and Analytics of Semantic Web Data." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112218/document.
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L'utilité et la pertinence des données se trouvent dans l'information qui peut en être extraite.Le taux élevé de publication des données et leur complexité accrue, par exemple dans le cas des données du Web sémantique autodescriptives et hétérogènes, motivent l'intérêt de techniques efficaces pour la manipulation de données.Dans cette thèse, nous utilisons la technologie mature de gestion de données relationnelles pour l'interrogation des données du Web sémantique.La première partie se concentre sur l'apport de réponse aux requêtes sur les données soumises à des contraintes RDFS, stockées dans un système de gestion de données relationnelles. L'information implicite, résultant du raisonnement RDF est nécessaire pour répondre correctement à ces requêtes.Nous introduisons le fragment des bases de données RDF, allant au-delà de l'expressivité des fragments étudiés précédemment.Nous élaborons de nouvelles techniques pour répondre aux requêtes dans ce fragment, en étendant deux approches connues de manipulation de données sémantiques RDF, notamment par saturation de graphes et reformulation de requêtes.En particulier, nous considérons les mises à jour de graphe au sein de chaque approche et proposerons un procédé incrémental de maintenance de saturation. Nous étudions expérimentalement les performances de nos techniques, pouvant être déployées au-dessus de tout moteur de gestion de données relationnelles.La deuxième partie de cette thèse considère les nouvelles exigences pour les outils et méthodes d'analyse de données, issues de l'évolution du Web sémantique.Nous revisitons intégralement les concepts et les outils pour l'analyse de données, dans le contexte de RDF.Nous proposons le premier cadre formel pour l'analyse d'entrepôts RDF. Notamment, nous définissons des schémas analytiques adaptés aux graphes RDF hétérogènes à sémantique riche, des requêtes analytiques qui (au-delà de cubes relationnels) permettent l'interrogation flexible des données et schémas, ainsi que des opérations d'agrégation puissantes de type OLAP. Des expériences sur une plateforme entièrement implémentée démontrent l'intérêt pratique de notre approcheThe utility and relevance of data lie in the information that can be extracted from it.The high rate of data publication and its increased complexity, for instance the heterogeneous, self-describing Semantic Web data, motivate the interest in efficient techniques for data manipulation.In this thesis we leverage mature relational data management technology for querying Semantic Web data.The first part focuses on query answering over data subject to RDFS constraints, stored in relational data management systems. The implicit information resulting from RDF reasoning is required to correctly answer such queries. We introduce the database fragment of RDF, going beyond the expressive power of previously studied fragments. We devise novel techniques for answering Basic Graph Pattern queries within this fragment, exploring the two established approaches for handling RDF semantics, namely graph saturation and query reformulation. In particular, we consider graph updates within each approach and propose a method for incrementally maintaining the saturation. We experimentally study the performance trade-offs of our techniques, which can be deployed on top of any relational data management engine.The second part of this thesis considers the new requirements for data analytics tools and methods emerging from the development of the Semantic Web. We fully redesign, from the bottom up, core data analytics concepts and tools in the context of RDF data. We propose the first complete formal framework for warehouse-style RDF analytics. Notably, we define analytical schemas tailored to heterogeneous, semantic-rich RDF graphs, analytical queries which (beyond relational cubes) allow flexible querying of the data and the schema as well as powerful aggregation and OLAP-style operations. Experiments on a fully-implemented platform demonstrate the practical interest of our approach
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Svensson, Gustav, and Jesper Nilsson. "Sänka bundet kapital i ett mellanlager : -En studie utförd i syfte att finna orsaken till varför lager bildas för att därefter presentera en eller flera åtgärder som bidrar till minskat bundet kapital i lager." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-41535.
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Purpose – Globalization affects all producing companies with increased complexity in production, stock management and never ending customer demands. The customers of today have a greater range of suppliers than before with even more products to choose from which puts the customer in a strong position. One of many important subjects that companies need to work with to keep their competitiveness strong against each other is to work with continuous improvements in production- and inventory management. This study therefore reviews tied up capital in stock and suggest adequate procedures, which could be applied to decrease the tied up capital. Method –In order to fulfil the purpose a case study is conducted. Two central research questions are chosen for the study to investigate in a case company. The data collected contains of secondary data, observations and interviews. To accomplish the purpose a theoretical framework has been put together. Findings – Reducing variations in production and re-designing of the daily production plan is presented as the two procedures with the purpose to achieve a decrease in tied up capital for stock kept units. The study describes these two procedures in general in order to make the solution applicable into various manufacturing company. Further the study claims that gaining flow efficiency should be prioritized instead of resource efficiency, which could be accomplished by the two procedures. Implications – The study contributes to verifying production theories, foremost about variations in production, Lean manufacturing and the technique of Lead-time mapping. Limitations – In order to apply the procedures with precision and efficiency some further data and extended studies needs to be performed. This study is performed in a generalizing point of view, which may influence the results. The study does not capture every aspect of affecting circumstances that might be needed for a successful implementation of suggested procedures. Keywords – Tied up capital, Lead-time, Lean, Lead-time mapping, Variations, Flow efficiency, Postponement, Just-in-Time, Make-to-stock and Make-to-order.Syfte – Globaliseringen har gjort att kunden har ett högre utbud att välja mellan och kan därmed ställa högre krav på tillverkande verksamheter. För att fortsatt vara konkurrenskraftig måste verksamheter ständigt utveckla den interna produktion- och materialstyrningen. Studiens ämnar därmed undersöka orsaken till uppkomsten av bundet kapital i lager samt finna potentiella åtgärder som kan vidtas inom verksamheten för att på ett hållbart sätt minska bundet kapital i lager. Metod – För att uppfylla studiens syfte tillämpas fallstudie. Studien utgår från två frågeställningar som besvaras med hjälp av data från ett fallföretag. Data som samlas är hämtad från sekundärdata, observationer och intervjuer. Därtill har ett teoretiskt ramverk upprättats vilken studien utgår ifrån. Resultat – Minska variationer samt utförande av en mer detaljerad planering presenteras som studiens två åtgärdsförslag för att minska bundet kapital i lager. Studien beskriver övergripande potentiella tillvägagångssätt för att åstadkomma förslagen. Studien konstaterar att flödeseffektivitet med fördel bör prioriteras framför resurseffektiviteten i verksamheten, vilket uppfylls med hjälp av åtgärdsförslagen. Implikationer – Studien bidrar inte till nya teorier men verifierar befintliga teorier främst kring variationer i tillverkning, Lean och ledtidskartläggning. Begränsningar – För att åtgärdsförslagen i studiens resultat ska kunna tillämpas krävs ytterligare data och fördjupade studier för att garantera att samtliga aspekter ska fångas in samt att orsak och påverkan av åtgärderna ska kunna kartläggas. Studien bygger på generaliserande antaganden vilket ger ett generaliserat resultat. Nyckelord – Lean, Ledtid, Ledtidskartläggning, Variationer, Flödeseffektivitet, Senareläggning, Just-in-Time, Make-to-order och Bundet kapital.
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Lluch-Ariet, Magí. "Contributions to efficient and secure exchange of networked clinical data : the MOSAIC system." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/388037.
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The understanding of certain data often requires the collection of similar data from different places to be analysed and interpreted. Multi-agent systems (MAS), interoperability standards (DICOM, HL7 or EN13606) and clinical Ontologies, are facilitating data interchange among different clinical centres around the world. However, as more and more data becomes available, and more heterogeneous this data gets, the task of accessing and exploiting the large number of distributed repositories to extract useful knowledge becomes increasingly complex. Beyond the existing networks and advances for data transfer, data sharing protocols to support multilateral agreements are useful to exploit the knowledge of distributed Data Warehouses. The access to a certain data set in a federated Data Warehouse may be constrained by the requirement to deliver another specific data set. When bilateral agreements between two nodes of a network are not enough to solve the constraints for accessing to a certain data set, multilateral agreements for data exchange can be a solution.
The research carried out in this PhD Thesis comprises the design and implementation of a Multi-Agent System for multilateral exchange agreements of clinical data, and evaluate how those multilateral agreements increase the percentage of data collected by a single node from the total amount of data available in the network. Different strategies to reduce the number of messages needed to achieve an agreement are also considered.
The results show that with this collaborative sharing scenario the percentage of data collected dramatically improve from bilateral agreements to multilateral ones, up to reach almost all data available in the network.
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Bieringer, Alexandra, and Linda Müller. "Integration of Internet of Things technologies in warehouses : A multiple case study on how the Internet of Things technologies can efficiently be used in the warehousing processes." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Centre of Logistics and Supply Chain Management (CeLS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-40087.
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Eriksson, Jonathan. "Towards a more efficient Supply Chain : A study at Bombardier Rail Control Solutions with a focus on centralizing their Supply Chain." Thesis, KTH, Industriell produktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-226163.
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To remain competitive in today’s business environment, companies must continuously become more efficient and improve their business. This can be achieved through developing and streamlining a company's Supply Chain. Bombardier Rail Control Solutions (RCS) has grown mainly through acquisitions, however, the acquisitions have not been integrated in a good way into their existing Supply Chain. This has result in a decentralized Supply Chain where RCS’s different sites are using different ERP systems. The consequence of this has led to an increased manual workload, a lack of visibility between sites and an inefficient Supply Chain. The goal of this project has been to identify how Bombardier RCS can develop and streamline its Supply Chain by centralizing different parts of it, e.g. ERP systems and different processes. To achieve this, there has been a close collaboration with Bombardier through the project through interviews, meetings, discussions together with studying literature. In addition, presentations have been presented continuously to ensure that the results have followed Bombardier RCS’s goal. RCS’s historical data has also been analyzed. Based on the above-mentioned methods, several problems have been solved and improvement areas have been identified. Issues that have been solved include centralizing master data and how to centralize processes at Bombardier RCS. Improvement areas include the benefits of centralizing Bombardier RCS Supply Chain and the advantages with a central warehouse. Bombardier RCS should also centralize their entire ERP system to enable global MRP calculations and so on. Furthermore, it has been identified that there is an improvement potential regarding Bombardier RCS's delivery performance, which can be solved by either integrating RCS’s Supply Chain or/and through keeping products on stock. The conclusion is that Bombardier RCS should centralize their Supply Chain step by step since it is impossible to centralize everything at once. By centralizing the Supply Chain, this can reduce manual workload, create visibility between different sites, contribute to a better delivery performance and streamline the Supply Chain. By doing this, Bombardier RCS can get more competitive, which can contribute to a continued strong market position in the industry.För att vara konkurrenskraftig i dagens företagsklimat måste företag ständigt förbättras och bli effektivare. Detta kan uppnås bland annat genom att utveckla och effektivisera ett företags värdekedja. Bombardier Rail Control Soutions (RCS) har växt framförallt genom företagsförvärv, dock har förvärven inte integrerats på ett bra sätt in i den existerande värdekedjan. Detta har resulterat i en decentraliserad värdekedja där RCS:s olika arbetsplatser använder olika ERP system. Konsekvensen av detta har lett till en ökande manuell arbetsbelastning, brist på synlighet mellan siter och en ineffektiv värdekedja. Målsättningen med det här projektet har varit att identifiera hur Bombardier RCS kan utveckla och effektivisera sin värdekedja genom att centralisera olika delar av den, exempelvis ERP system och olika processer. För att uppnå detta har ett nära samarbete med Bombardier genom projektet varit centralt med intervjuer, möten och diskussioner, tillsammans med en litteraturstudie. Dessutom har presentationer framförts kontinuerligt för att säkerställa att resultaten följt Bombardier RCS:s mål. RCS:s historiska data har också analyserats. Utifrån ovannämnda metoder har flera problem löst och förbättringsområden har identifierats. Problem som har lösts är bland annat att centralisera RCS:s masterdata och hur man kan centralisera processer hos Bombardier RCS. Förbättringsområden är bland annat fördelarna med att centralisera Bombardier RCS:s värdekedja och vinsterna med ett centrallager. Bombardier RCS bör även centralisera deras ERP-system för att möjliggöra globala MRP-beräkningar och så vidare. Vidare har det identifierats att det finns en förbättringspotential för Bombardier RCS:s leveransprecision som kan lösas dels med att integrera värdekedjan (med leverantörer) eller/och lagerlägga artiklar. Slutsatsen är att Bombardier RCS bör centralisera sin värdekedja stegvis eftersom det är omöjligt att centralisera allt på en gång. Genom en centraliserad värdekedja kan det minimera den manuella arbetsbelastningen, skapa visibilitet mellan olika arbetsplatser, bidra till en bättre leveransprecision och effektivisera värdekedjan. Genom att göra detta kommer Bombardier RCS bli mer konkurrenskraftig, vilket kommer bidra till en fortsatt stark marknadsposition i branschen.
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Idris, Muhammad. "Real-time Business Intelligence through Compact and Efficient Query Processing Under Updates." Doctoral thesis, Universite Libre de Bruxelles, 2019. https://dipot.ulb.ac.be/dspace/bitstream/2013/284705/5/contratMI.pdf.
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Responsive analytics are rapidly taking over the traditional data analytics dominated by the post-fact approaches in traditional data warehousing. Recent advancements in analytics demand placing analytical engines at the forefront of the system to react to updates occurring at high speed and detect patterns, trends, and anomalies. These kinds of solutions find applications in Financial Systems, Industrial Control Systems, Business Intelligence and on-line Machine Learning among others. These applications are usually associated with Big Data and require the ability to react to constantly changing data in order to obtain timely insights and take proactive measures. Generally, these systems specify the analytical results or their basic elements in a query language, where the main task then is to maintain query results under frequent updates efficiently. The task of reacting to updates and analyzing changing data has been addressed in two ways in the literature: traditional business intelligence (BI) solutions focus on historical data analysis where the data is refreshed periodically and in batches, and stream processing solutions process streams of data from transient sources as flows of data items. Both kinds of systems share the niche of reacting to updates (known as dynamic evaluation), however, they differ in architecture, query languages, and processing mechanisms. In this thesis, we investigate the possibility of a reactive and unified framework to model queries that appear in both kinds of systems.In traditional BI solutions, evaluating queries under updates has been studied under the umbrella of incremental evaluation of queries that are based on the relational incremental view maintenance model and mostly focus on queries that feature equi-joins. Streaming systems, in contrast, generally follow automaton based models to evaluate queries under updates, and they generally process queries that mostly feature comparisons of temporal attributes (e.g. timestamp attributes) along with comparisons of non-temporal attributes over streams of bounded sizes. Temporal comparisons constitute inequality constraints while non-temporal comparisons can either be equality or inequality constraints. Hence these systems mostly process inequality joins. As a starting point for our research, we postulate the thesis that queries in streaming systems can also be evaluated efficiently based on the paradigm of incremental evaluation just like in BI systems in a main-memory model. The efficiency of such a model is measured in terms of runtime memory footprint and the update processing cost. To this end, the existing approaches of dynamic evaluation in both kinds of systems present a trade-off between memory footprint and the update processing cost. More specifically, systems that avoid materialization of query (sub)results incur high update latency and systems that materialize (sub)results incur high memory footprint. We are interested in investigating the possibility to build a model that can address this trade-off. In particular, we overcome this trade-off by investigating the possibility of practical dynamic evaluation algorithm for queries that appear in both kinds of systems and present a main-memory data representation that allows to enumerate query (sub)results without materialization and can be maintained efficiently under updates. We call this representation the Dynamic Constant Delay Linear Representation (DCLRs).We devise DCLRs with the following properties: 1) they allow, without materialization, enumeration of query results with bounded-delay (and with constant delay for a sub-class of queries), 2) they allow tuple lookup in query results with logarithmic delay (and with constant delay for conjunctive queries with equi-joins only), 3) they take space linear in the size of the database, 4) they can be maintained efficiently under updates. We first study the DCLRs with the above-described properties for the class of acyclic conjunctive queries featuring equi-joins with projections and present the dynamic evaluation algorithm called the Dynamic Yannakakis (DYN) algorithm. Then, we present the generalization of the DYN algorithm to the class of acyclic queries featuring multi-way Theta-joins with projections and call it Generalized DYN (GDYN). We devise DCLRs with the above properties for acyclic conjunctive queries, and the working of DYN and GDYN over DCLRs are based on a particular variant of join trees, called the Generalized Join Trees (GJTs) that guarantee the above-described properties of DCLRs. We define GJTs and present algorithms to test a conjunctive query featuring Theta-joins for acyclicity and to generate GJTs for such queries. We extend the classical GYO algorithm from testing a conjunctive query with equalities for acyclicity to testing a conjunctive query featuring multi-way Theta-joins with projections for acyclicity. We further extend the GYO algorithm to generate GJTs for queries that are acyclic.GDYN is hence a unified framework based on DCLRs that enables processing of queries that appear in streaming systems as well as in BI systems in a unified main-memory model and addresses the space-time trade-off. We instantiate GDYN to the particular case where all Theta-joins involve only equalities and inequalities and call this instantiation IEDYN. We implement DYN and IEDYN as query compilers that generate executable programs in the Scala programming language and provide all the necessary data structures and their maintenance and enumeration methods in a continuous stream processing model. We evaluate DYN and IEDYN against state-of-the-art BI and streaming systems on both industrial and synthetically generated benchmarks. We show that DYN and IEDYN outperform the existing systems by over an order of magnitude efficiency in both memory footprint and update processing time.Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
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Ranarifidy, Harison. "La gestion de la diversité culturelle des équipes dans les entrepôts logistiques : lien entre diversité culturelle et performance." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0062.
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Notre idée est d’élaborer le modèle conceptuel de recherche du lien diversité / performance issu de la littérature, donc concernant le top management. Ce modèle sera ensuite transposé via l’analyse, selon la méthode GIOIA, des verbatims de nos entretiens auprès des managers d’entrepôts pour aboutir à un modèle conceptuel concernant l’emploi peu qualifié de l’entrepôt. Pour que la diversité culturelle des équipes des entrepôts soit source de performance, nous préconisons une approche globale par la mise en œuvre, à l’intérieur de l’entreprise de rattachement de l’entrepôt, de dispositifs managériaux composés de politique de diversité culturelle soucieuse d’inscrire le changement dans la durée, de management cohésif attentif aux dimensions culturelles et de leadership attentif à la diversité culturelle. Au sein de l’entrepôt seront mises en place les pratiques GRH spécifiques à l’entrepôt logistique qui renforcent l’implication organisationnelle et qui tiennent compte des leviers de gestion de la diversité précitésOur idea is to elaborate the conceptual model of research of the link diversity / performance resulting from the literature, thus concerning the top management. This model will then be transposed via the analysis, according to the GIOIA method, of the verbatim of our interviews with the warehouse managers to arrive at a conceptual model concerning the low-skilled use of the warehouse.To ensure that the cultural diversity of the warehouse teams is a source of performance, we recommend a global approach by implementing, within the warehouse's parent company, managerial systems composed of anxious cultural diversity policy. to inscribe change over time, cohesive management attentive to cultural dimensions and leadership attentive to cultural diversity.Within the warehouse will be implemented HRM practices specific to the logistics warehouse that strengthen organizational involvement and that take into account the aforementioned diversity management levers
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Lepori, Elvia. "Conception d'un système de mesure de la performance pour la réorganisation des activités d'entrepôt : quelle cohérence avec le système de contrôle de gestion ?" Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAB003.
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En quête de performance, les Third-party Logistics (3PL) sont amenés à réorganiser régulièrement leurs activités d’entrepôt. Peu d’études portent sur les systèmes de mesure de la performance (SMP) dédiés au 3PL. Les auteurs étudient les activités indépendamment les unes des autres alors qu’il existe des relations de cause à effet entre ces dernières. La conception d’un SMP pour la réorganisation des activités conduit à nous interroger sur ses conséquences pour le système de contrôle de gestion, au travers du cadre théorique de Simons.Une Recherche-Intervention est réalisée au sein du 3PL : FM Logistic. Notre contribution porte sur la conception d’un SMP sous forme de graphe de problèmes mettant en relation les connaissances sur la réorganisation des activités des experts et de la littérature scientifique. Ce SMP est construit à partir d’un langage inspiré de la théorie TRIZ. La conception du SMP permet l’analyse de l’évolution d’un contrôle de gestion diagnostique vers l’interactivitéThird-party logistics (3PL) seek performance by reorganizing regularly their warehouse operations. Few researchers study performance measurement systems (PMS) dedicated to 3PL. Researchers in warehousing design are used to study all the different operations one by one while these operations are linked together. As far as we know the literature does not propose any SMP for warehouse operations reorganization. SMP design leads to analyze the consequences for management control system, studied through Simons’ levers of control.An Intervention-research is conducted in a french 3PL : FM Logistic. Our contribution is the design of a performance measurement system in the form of problem graph which linking both knowledge advocated by a French 3PL and quoted in the literature. This SMP has been designed using a semantic and a syntax inspired by TRIZ problem graph. SMP design enables to analyze interactivity development. Results show the development of diagnostics systems towards interactivity
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Ayadi, Abdessalem. "Vers une organisation globale durable de l’approvisionnement des ménages : bilans économiques et environnementaux de différentes chaînes de distribution classiques et émergentes depuis l’entrepôt du fournisseur jusqu’au domicile du ménage." Thesis, Lyon 2, 2014. http://www.theses.fr/2014LYO22010/document.
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La logistique urbaine, et celle du dernier kilomètre notamment, est un sujet de préoccupation majeure pour les villes d’aujourd’hui. Pour répondre à cette préoccupation, nous avons établi dans le chapitre introductif un historique de la problématique de la logistique urbaine pour mieux comprendre son développement au fil des années, permettant ainsi de déduire qu’il est fondamental d’étudier la globalité de la chaîne de distribution dans ce travail de thèse pour mieux résoudre la problématique de la logistique urbaine. En revanche, nous étions confrontés à un sujet redoutable par sa complexité et l’absence de données complètes et fiables. De plus, nous assistons dans les dernières années, à une multiplication des schémas logistiques que ce soit pour la livraison des magasins à partir des entrepôts des fournisseurs ou pour l’approvisionnement des clients à partir des surfaces de vente.De ce fait, nous avons fixé comme objectif d’identifier toutes les organisations logistiques existantes et émergentes en France et ailleurs (deux séjours d’un an en Angleterre et en Suisse). Pour ce faire, nous avons déterminé dans le deuxième chapitre les paramètres de différenciation des modes d’organisation en amont (de l’entrepôt du fournisseur à la surface de vente) et en aval de la chaîne (de la surface de vente au domicile du client). Or il n’existe pas aujourd’hui de bilan économique et environnemental complet permettant d’arbitrer entre différentes formes de distribution classiques et à distance en tenant compte des particularités des familles des produits (non alimentaires, secs, frais, surgelés) et de la diversité de leurs modes de livraison.Face à ces contraintes de taille, nous avons eu recours aux enquêtes de terrain dans ce travail de recherche, qui ont été l’occasion de nouer de très nombreux contacts avec les acteurs de la grande distribution, permettant ainsi de recueillir des données techniques et économiques de première main et inédites jusqu’ici. En plus de la résolution du verrou empirique dans le troisième chapitre, ce travail de thèse a permis également de lever des verrous méthodologiques relatifs à la reconstitution et à l’évaluation des coûts et des émissions logistiques (pour les entrepôts de stockage et les plateformes de transit en amont ; et pour les surfaces de vente et les plateforme de mutualisation en aval) et des coûts et des émissions des véhicules de transport (des articulés et des porteurs en amont ; et des VUL, voitures particulières, transports publics, deux roues, et marche à pied en aval). Enfin, ce travail de thèse a permis d’aboutir à la construction d’une base de données et la mise au point d’un outil d’aide à la décision permettant ainsi de déduire, dans le quatrième chapitre, les bilans économique et environnemental de la globalité de la chaîne depuis l’entrepôt du fournisseur jusqu’au domicile du ménage. Cet outil devrait se révéler très utile pour les politiques publiques, les stratégies futures des grands distributeurs et leurs prestataires logistiques afin de privilégier les modes d’organisation économes et durables, et même pour le client final afin d’estimer les coûts et les émissions de ses actes d’achat dans les différentes alternatives de vente classique et à distanceUrban logistics and the last mile in particular, is a major concern for cities today. To address this concern, we have established in the introductory chapter a history of the problem of urban logistics. This allows a better understanding of its development over the years, and deducing that it’s essential to study the supply chain in its entirety to better solve the problem of urban logistics. However, we were faced with a daunting task: the lack of comprehensive and reliable data. In addition, there has been a multiplication of distribution channels in recent years. This includes the delivery from warehouses to stores and further to households from the retail space.Therefore, we intended to identify all existing and emerging logistics organizations in France and beyond (one year exchange stay in England and Switzerland for research purposes). To do this, we established in the second chapter certain parameters that differentiate the logistics modes of various organizations upstream (from manufacturers to retail stores) and downstream (from retail stores to households). Unfortunately, there does not exist any economic and environmental assessment to settle between different forms of traditional and modern electronic distribution, by taking into account the various characteristics of different products families (non-food, dry, fresh, frozen) and the diversity of their delivery modes.Faced with constraints of such size, we conducted surveys with different actors of distribution channels, which provided the opportunity to make contacts, thus collect firsthand and so far unpublished technical and economic data. In addition to the resolution of empirical inadequacy in the third chapter, this research also helped to develop a methodological approach related to the reconstruction and evaluation of logistics costs and emissions (in warehouses, transit platforms, retail stores and shared platforms) and also the costs and emissions of vehicles (trucks, delivery van, cars, public transport, bikes, motorbikes and walking).Finally, this research has lead to the construction of a database and the development of a decision support tool to infer, in the fourth chapter, the economic and environmental appraisal of the entire supply chain from the supplier's warehouse to the final customer. This tool can be useful for public policy, future strategies of retailers and Third-Party Logistics providers to focus on efficient and sustainable modes of organization, and even it will benefit the customer to estimate the costs and emissions of its acts of purchase in classic and e-grocery shopping
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Li, Yung-chih, and 李永志. "A Study on The Operation Efficiency of Warehouse Using iDEAs-An Example of an Air Force Warehouse Center." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/82473883670566962309.
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碩士義守大學
工業工程與管理學系碩士班
93
The enterprise competition in pursuing globalization in these recent years urges the gradual prosperous development of domestic logistics industry. Among which, besides the newly established logistics warehousing business, the original enterprise with simple transportation form is also gradually experiencing transformation and developing into comprehensive logistics operation. Logistics operation includes “Customer Reply”, “Functions of Inventory Planning and Management”, “Supply”, ”Transportation”, “Warehouse Operation” and etc, while warehouse operation plays the important role of connecting manufacturer with terminal users, and therefore, it is imperative to discuss its operation achievements. For the rear service system of National Armed Forces, logistics operation even bears the contact establishment of the whole combat ability. However, National Armed Forces is confronted with the gradual reduction of national defense budget in these recent years and they should develop the largest benefit with a few resources, so evaluating the warehouse logistics achievements of military affairs unit will be contributive to improve the internal operation achievements of National Armed Forces.This study mainly uses the Performance Appraisal Systems iDEAs developed by Georgia Institute of Technology, United States as the analysis tool to be introduced into certain warehouse center of Air Force as the discussion of related military affairs warehouse achievements, where the analysis technology applied by iDEAs system is the Data Envelopment Analysis method that is extensively applied on performance appraisal as analysis theory. The 159 optimization related warehouse logistics companies that are searched and collected through iDEAs system are used as the benchmark of comparison analysis to carry out efficiency analysis, and thereafter, uses difference variable analysis to improve invested resources; lastly, uses sensitivity analysis investment value combination to improve the influence of efficiency value, to find out the investment value with the largest influence level to help case unit to control the superiority of improving efficiency. The study result shows that after comparing it with iDEAs optimization benchmark unit, the case has excessively investment in fund and labor resources, and the yield in bulk, packaging, and warehouse stock is not enough, which results in less good value of the whole efficiency. Wholly speaking, the labor hour, equipment Investment dollar, broken case , full case, and pallet case and output item with the most influence on efficiency value, therefore, appropriate control of this investment, output item will be contributive to the improvement of case efficiency value.
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Hsiao, Chun Fu, and 蕭俊富. "The Study For Enhancing Picking Efficiency In Automotive serrvice-Parts Warehouse." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/a6k4y7.
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碩士國立臺北科技大學
車輛工程系所
95
ABSTRACT Title: Enhancing Picking Efficiency For Service Parts Of Automotive Warehouse Page:149 School: National Taipei University of Technology Department: Vehicle Engineering Time: July 2007 Degree: Master Researcher: Chun Fu Hsiao Advisor: Shiuh Jer Huang Keywords: The mainly studying method of this thesis is briefly learning and introducing top Global automakers, global automotive component manufacturers, and domestic car-making industry and prediction of its future. Data and information Collection from automakers and automotive components manufactures, reference to the academic literatures, interview of domestic car-maker’s executive officers, these data, information and academic literatures, and executive officers’ interview will put together and be experimented in the physically routine warehouse operation. Through study, research, and physical operation to prove the theory can be feasible to be adopted. The subject of Supply Chain in the automotive industry, specially mentioned After-sales function, it can function as sales forecasting, placing orders, goods receiving, put-away to shelf, inventory management, sales order processing, picking & packing, delivery and logistic, and, finally, invoicing and financing. Different industries for the above key words have their definitions, and there are somehow a little bit difference. The key words will be defined by the viewpoint of automotive industry and expect studiers and researchers to fully realize them without deviation of mainly studying Pertaining to the mainly subject of studying, Enhancing Picking Efficiency For Service Parts Of Automotive Warehouse, it is quite concentrated and focused studying subject. For studying it, the warehouse operating functions and processing ought to be fully understanding and realizing before commencing studying. The functions such as preparing initial inventory to meet the market demand, placing orders to the foreign sources, selecting forwarder and custom broker for declaring and custom clearance, applying the goods declaration before taxing, invoice and packing list automatically download and eat-in to warehousing management system, goods receiving and put-away, receiving customers’ order, picking and packing, goods delivered route, and finally night shipped arrangement. Each respective function is closely linked warehouse routine operations. The first step of studying is concentrating on realizing respective function of warehouse, and then narrows down to the mainly subject, Enhance Picking Efficiency For Automotive Warehouse. Through the systematic analysis for parts sales history, the hit rate will be identified and then parts stock locations will be re-designed and re-located. This purpose is expecting that the picker can pick more parts in the same time frame. It means that picking the same items and quantities will use less time compared to the before parts re-location. The time and manpower saving can use to support other functions which need more manpower. As most warehouse operation, the parts no on the picking order is sorted by aisle-bin number, therefore, the picker will be walking around the whole warehouse to implement this picking order. It is definitely waste the time and picker energy. Imagine, if the warehouse can be setup a golden zone, and put the highest hit-rate parts into this golden zone, the picker just surrounds the golden zone to pick all he or she need to pick. It should save picker’s time and energy, certainly improve the picking efficiency. As a automotive service parts warehouse, its parts stock shelves can be categorized into three types, small size, middle size, big or over-weight shelf. Different size parts ought to put into his designated shelf. The meaning of parts re-location is expressing that highest hit-rate parts which parts size and shape are quite similar are putting into the same area. The area is named golden zone. As a result, the picker just walks through the golden zone to pick what he wants to pick. Eliminate the waste, save picking time and picker energy, this is the mainly purpose of this study.
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Xin, Jun Huang, and 黃信鈞. "Efficiency improvement of the warehouse managementof supply chain-“A” campany case study." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/fxhbs3.
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碩士國立屏東科技大學
環境工程與科學系所
104
In order to incease itself competitveness production capacity and raise of environmental awareness, modern enterprises use advanced auto-warehouse management system has fast、reliable 、renew the dataimmediately and reduce goods breakdown by human factor to persue the stability of supply and shipment、avoid the bullwhip effect of the supply chain management and excellent environmental protection equipment in response to competitiveness increasing in opposition to increase the pollution to monitor the situation and prevent the excessive of pollution emission to achieve the target of energy saving and waste reduction. The study selects a tradional warehouse management system company to improve and choose three example company include Retail Support International、CTW Logitics Corporation and Formosa Plastics Group. They all use the advantage of auto-warehouse management system and equipment and improve the environment protection equipment to integrate. The study draws up a warehouse management system and equipment with environment protection equipment fit A company to probe to analyze the degree of improve efficiency. Among the example companies in the warehouse management side, they all use the warehouse management equipment. On the other side,Retail Support International uses EOS、POS and RFID,CTW Logistics Corperation uses ERP integration and Formosa Plastics Group uses work station computer setting up. In the environment protection side, Retail Support International uses the system of transport routes by computer planning、CTW Logistics Corporation uses biodiesel for transporter use and Formose Plastics Group uses taking excellent pretreatment and dust collection process in the fired power plant operation. After drawing up the new auto-warehouse management system equipment and environment protection, it can save the company total cost amount about NT 11,750,913 dollars , then it can increase 120 company orders、save times about 4,925 hours and control the rate of unusal exhaust under 1%. Then in the pollution emissions side, dust drops to 2 mg/Nm、odor dilution time drops to 3750 times. Therefore, the new economic price and enormous benefit system can let A company enhance efficiency, then it has both energy saving and waste reduction.
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Oliveira, Maria João Miranda do Couto. "Framework to evaluate and improve E-commerce Efficiency in a Logistics Warehouse." Dissertação, 2002. https://repositorio-aberto.up.pt/handle/10216/113716.
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Oliveira, Maria João Miranda do Couto. "Framework to evaluate and improve E-commerce Efficiency in a Logistics Warehouse." Dissertação, 2018. https://hdl.handle.net/10216/113716.
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Oliveira, Maria João Miranda do Couto. "Framework to evaluate and improve E-commerce Efficiency in a Logistics Warehouse." Master's thesis, 2018. https://hdl.handle.net/10216/113716.
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Wu, Chih-Hsien, and 吳志賢. "Research on pick up efficiency of a multi-level rack warehouse– Taking a down-grade LCD panel storage warehouse as an example." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/51345364696994069823.
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碩士國立成功大學
工業與資訊管理學系專班
94
In the research of traditional warehouse picking efficiency, most studies consider single-level rack warehouses, or focus on AS/RS (Automated storage/ retrieval system) systems. Few consider traditional multi-level rack warehouses. However, most companies use traditional multi-level rack warehouses rather than AS/RS systems due to economic reasons. Further, traditional multi-level rack warehouses create more space for storing goods than single-level rack warehouses with a reasonable investment. Taking a downgrade panel storage warehouse as an example, this thesis has considered the difference of moving distance between vertical and horizontal storage. That is, minimum moving distance does not means minimum picking time. This thesis explores the picking efficiency under different combinations of storage assignment and picking route strategies, and compare their performances by using a simulation software.
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Lin, Chuang-Hung, and 林壯鴻. "The Efficiency of Department Store Systems, Warehouse Store Systems, and Convenience Store Systems in Taiwan." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/49172085042003859165.
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碩士國立交通大學
經營管理研究所
91
Increasing living and educational levels have drastically changed consumers’ shopping behavior. The rise of distribution centers has caused the traditional multiple and complex shipping channels to alter: All suppliers and venders nowadays ship goods first to a distribution center, and then a distribution center deliver the goods directly to retail stores. Distribution centers have promoted the numbers of chain stores, department stores, and wholesale stores. This study evaluates efficiencies of department stores, warehouses, and convenience stores in Taiwan and investigates the factors affecting efficiencies. In our data set, there are 12 department store systems, 5 warehouse systems, and 5 convenience store systems in Taiwan during 1997 to 2000. First, the panel-data, stochastic frontiers model developed by Battese and Coelli (1995) is used to compute the technical efficiencies of these retail store systems. Second, the data envelopment analysis (DEA) developed by Charnes, Cooper and Rhodes (1978) is applied to evaluate their technical efficiencies. Empirical finding from these two methods are consistent. Four major findings are made: 1.A decrease in the sales floor and an increase in the number of stores significantly improve a convenience store system''s efficiency. 2.A larger sales floor significantly decreases a warehouse system''s efficiency. 3.An increase in the sales floor and a decrease in the number of stores significantly improve a department store system''s efficiency. 4.The rankings in efficiency are, from the highest to the lowest, convenience store systems, department store systems, and wholesale warehouse systems.
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Huang, Tsao-Cheng, and 黃兆誠. "Implementing Lean technology to enhance operational efficiency in Warehouse – A Case Study of SME Fabless IC design house." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/encdyy.
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碩士中原大學
工業與系統工程研究所
103
The purpose of this study is to implement the lean production model and the improvement of lean structure in a warehouse of a SME Fabless IC design hours. Consequently, a case study of implementing lean production to improve the operational waste and enhance the productivity was discussed. The management thinking and techniques is the core of this study. Besides, this study discusses how to apply the analysis technique of VSM in warehouse to enhance operational efficiency. Utilizing the analysis of VSM is the key component as a primary research tool and improved method to discover the waste which a case company makes in its operational processes. Ultimately the warehouse of the case company with this study model of lean production, which includes improvement in basic stage of lean implementation, integration in RFID technology and combination of every equipment on-site, makes the total operation time decrease more than double and reduce the average error rate of less than one percent for the operator. Eventually, the overall work efficiency and operation quality get improved.
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Fu, Tzu-Hao, and 傅子豪. "Applying QC STORY to Improve the Efficiency of Warehouse Operations - A Case Study of a Solar Energy Company." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/p43s35.
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GUO, YOU-JIA, and 郭祐嘉. "Improving Pick Efficiency of The Warehouse by Using Association Rules on Storage Arrangement—A Case Study of Company Ｈ." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/ce22tn.
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碩士國立高雄應用科技大學
工業工程與管理系碩士班
104
The company H is a groceries wholesalers, which need better picking efficiency to provide faster service for customer demand, the warehouse of H company still rely on a manual picking form. Therefore, there is a goal to improve picking efficiency of the warehouse by this study, the first storage arrangement step is statistical frequency of each items from the order form, and then assign the highest frequency items near to I/O sequentially and lowest frequency ones farther from I/O. Then mining frequent itemsets from the transaction database of company H and make a second storage adjustment. Make compare with the original warehouse arrangement and selected preferred configuration. Then achieve the goal of reduce picking routing and time has be achieved.
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YUAN, CHEN JUI, and 陳瑞元. "Research Analysis and Suggestions on Increasing the Revenue of In-flight Duty-Free Merchandise and Improving the Operation Efficiency of Bonded Warehouse." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/32wn33.
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碩士逢甲大學
纖維與複合材料學系
106
The aviation industry is a very competitive industry. Operating reve-nues comes from the passenger earnings, air cargo transportation and air-craft maintenance. In terms of gaining profit from air tickets, it depends on its route, safety, quality and service, etc. Theoretically, increased income will lead to increased business revenues. Because there are many authori-zation related issues in aircraft maintenance, the profit of adequate mainte-nance stays relatively stable. Airline fuel continues to be the largest sin-gle cost item, which collectively accounts for 40% of total airline cost for the global airline industry. Therefore, airline operation is undoubtedly a highly competitive market, the total items of the incomes and expenditures are extremely important. The sales of duty-free goods on board is a unique travel retailing channel, which is becoming one of the major income sources for airline operation. The domestic aviation market has expand-ed and grown rapidly over the past years. The annual net income of do-mestic airlines is about one billion to two billion- contributing about hun-dreds of millions of profits to achieve the stable profitability. According to the current regulations, the duty-free goods must be stored in the bonded warehouse first, then put into the duty-free carts, selling boxes and selling bags before being sent on board for sale, to be served to the passengers (e.g. food and beverage), or as supplies for returning flight from overseas. The current management of in-flight duty-free goods is running stably. The purpose of this paper is to discuss how to increase the revenue. The data and information used in this paper are legally collected by interview-ing senior management with decision-making power of airline companies and related corporations. After a series of analyses, we have some suggestions to increase the reve-nue of the in-flight duty-free goods. For example, there are always a few top selling items running out of stock. The airline companies and bond-ed warehouses can adjust the quantities and the categories of duty-free items for sale on board according to the sales data- the slow-moving items can be replaced by top selling items, which can increase the sales. We hope our recommendations can help in gaining more revenue for air-line companies and related corporations.
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CHEN, JIAN-LONG, and 陳建龍. "Effects of Application of Barcodes in Wafer Warehouse Process on Work Efficiency and Job Satisfaction-A Case Study of a Semiconductor Packaging and Testing Company A." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/7mwb2w.
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碩士中華大學
工業管理學系
104
As the market change, the semiconductor industry has fiercer competition than other industries. Additionally, the IC packing and testing plants confront the same status. Packing and testing are one portion of the integrity of semiconductor supply chain and as sub-area in the factory. However, it is impossible for small and medium size seals only to serve one customer and still possess the competitive advantage. Nevertheless, the WAFER of a seal stand is the wafer warehouse that deposits in and sends away all customers. However, as more and more clients deliver WAFER to the A Corporation, how to effective management is a major issue. Under the situation of limited production time, if there is any missing on wafer warehouse in WAFER inventory that will create the detention of the entire production line operation. This study is presenting a department unit after to receive goods in the system not really perfect situation to induct the benefit as well as to the enterprise interior other departments chain-like effect which the bar code system produces primarily. In the review country, inside and outside literature has the discovery research related semiconductor to seal measured are very many in the management literature, but receives goods in the work literature in the whole using the bar code improvement really to be actually few, therefore this research is seals by a semiconductor measured the factory the wafer warehouse is an example, discusses receives in the material flow using barcode and the material collector in the wafer warehouse the result analysis. The study by way of discovering the key aspect with the case company personnel interview to design the questionnaire to carry on the analysis, by is connected the worker to work satisfaction as well as the whole working efficiency carries on by way of the narrative statistics the data the factor analysis. Reliability analysis: above a baseline of 0.7, a greater value of Cronbach’s α.The internal consistence between the barcode system and the constructs of wafer warehouse operations is tested with Cronbach’s α.The factor analysis in this study involves the following steps:1.KMO value above 0.7 considered optimal.2.Principal component analysis of the factor analysis that followed the KMO analysis is used to extract common factors by the criteria of eigenvalue greater than 1 for the number of factors to be chosen.3.Select the factors with factor loading greater than 0.45 as constructs and rename them. The extract primary factor five suppositions which proposed by way of two big construction surface carries on the confirmation, analysis results for the bar code system in pick up time is reduced, location accuracy, data transparency and job satisfaction and work achievement are all five surface structure <α = 0.05 significant hoped this research will be able to want for the future to induct industry of the bar code system to provide one is divided the correlation practical material and the reference.
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Lin, Jing-Tang, and 林景堂. "Efficient Computation of ContinuousAggregation Queries on Data Warehouse." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/09733746068377733588.
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碩士國立中央大學
資訊工程研究所
95
Data Warehouse usually stores a large amount of historical data. User’s aggregate queries usually have to consume a large amount of time and system resources in order to analyze a large amount of data in data warehouse. The response time of these aggregate queries is typically several orders of magnitude higher than the response time of OLTP (Online Transaction Processing) queries. Because that, how to reduce their response time is becoming increasingly important. The concept of materialized view is well suited to the data warehouse environment. We offer a method to construct DAG (Directed Acyclic Graph) base on the derived situation between these aggregate queries. And then, we modify the depth-first search algorithm to travel this DAG. Finally, we will find out a queries execution order has well improve performance under the space constraint restricted by the data warehouse system.
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Duro, Bruno Artur Nunes. "Manutenção de instalações elétricas: Plano de manutenção para edifício DEEC." Master's thesis, 2016. http://hdl.handle.net/10316/81590.
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Dissertação de Mestrado Integrado em Engenharia Electrotécnica e de Computadores apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.This study was made in the context of my Integrated Master?s Thesis in Electrical and Computer Engineering, taught at the Electrical and Computer Engineering Department- Faculty of Sciences and Technology of the University of Coimbra, in the academic year 2015/2016.During the last years, we have seen a continuous increase on the demand and price of electrical energy. According to European Union data, a significant quantity of that amount is related with the demand of energy from buildings, from services and housing.Maintenance can be defined as the set of actions to ensure the proper functioning of the machines and installations, ensuring that they suffer intervention on the right moment and range, according to good technical practices and legal requirements in order to avoid loss of function or degradation of performance, and if it does, to be restored in good operating conditions as soon as possible, and all at an optimized overall cost. (Cabral, 2013)Preventive maintenance of technical installations is, among other things, one of the essential tools to increase the life of installations and components that constitute them, and thus improves the comfort of users.A maintenance plan of electrical installations (main objective of this masters dissertation) should be weighted and appropriated to the characteristics and requirements of the building, in this case the building of the Department of Electrotechnical and Computer Engineering, taking care of the way as it is structured, which measures to take and what periodicity of interventions to consider in order to increase the reliability of its services and the energetic efficiency of the building, maximizing the available resources in order to ensure greater protection and comfort to the user, among others.Initially it was performed a general characterization of the major electrical building installations, identifying all the circuits inserted in a database. Subsequently were analyzed and listed preventive maintenance measures according to their needs, taking into account the legislation in force. They were also set periodicity interventions for preventive maintenance and was also created some maintenance support forms in order to record the events detected in the building, to specify the operations performed when a failure occurs to conduct a control of the time spent in solving the event, as well as to justify the employment of components replaced when applicable.Some forms have been created to assist carefully the management of materials, including the warehouse of existing materials in stock.
O presente trabalho foi desenvolvido no âmbito da Dissertação de Mestrado Integrado em Engenharia Eletrotécnica e de Computadores, lecionada no Departamento de Engenharia Eletrotécnica e de Computadores da Faculdade de Ciências e Tecnologia da Universidade de Coimbra, no ano letivo 2015/2016.Nos últimos anos, tem-se assistido a um crescente aumento do consumo e do custo da energia elétrica. De acordo com dados da União Europeia, uma percentagem significativa deste aumento de consumo está relacionada com o consumo de energia em edifícios, de serviços e de habitações.A manutenção pode definir-se como o conjunto das ações destinadas a assegurar o bom funcionamento das máquinas e instalações, garantindo que são intervencionadas nas oportunidades e com o alcance certo, de acordo com as boas práticas técnicas e exigências legais, de forma a evitar a perda de função ou redução do rendimento e, no caso de tal acontecer, que sejam repostas em boas condições de operacionalidade com a maior brevidade, e tudo a um custo global otimizado. (Cabral, 2013)A manutenção preventiva das instalações técnicas é, entre outros aspetos, uma das ferramentas essenciais na redução desta fatura energética, além de aumentar a vida útil das instalações e componentes que as constituem e, consequentemente, melhora o conforto dos utentes.Um plano de manutenção das instalações elétricas (foco da presente dissertação) deve ser ponderado e adequado ás caraterísticas e exigências do edifico, neste caso, o edifico do Departamento de Engenharia Eletrotécnica e de Computadores da Universidade de Coimbra, tendo o cuidado da forma como é estruturado, quais a medidas a adotar e qual a periocidade das intervenções a considerar de modo a aumentar a eficiência energética do edifício, rentabilizando os recursos disponíveis por forma a garantir uma maior proteção e conforto ao utilizador, entre outras.Numa fase inicial foi feita uma caraterização geral das principais instalações elétricas do edifício, com a identificação dos circuitos elétricos constituintes dos quadros elétricos principais e registo de toda a informação em base de dados. Posteriormente foram analisadas e apresentadas medidas de manutenção preventiva de acordo com as suas necessidades, tendo em conta a legislação em vigor. Foram também definidas periodicidades das intervenções de manutenção preventiva e criados alguns formulários de apoio à manutenção por forma a registar as ocorrências detetadas no edifício, para especificar as intervenções realizadas quando ocorre uma avaria, para realizar um controlo do tempo despendido na resolução do acontecimento, bem como para justificar a empregabilidade dos componentes substituídos quando aplicável.Foram ainda criados alguns formulários para auxílio à gestão criteriosa do aprovisionamento de materiais, incluindo o controlo do inventário de stock de material existente.
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Khalil, Moayad. "IMPROVING EFFICIENCY OF ORDER PICKING IN PICKER-TO-PARTS WAREHOUSES." 2013. http://hdl.handle.net/10222/42643.
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Order picking is considered one of the most time-consuming operations in picker-to-parts warehouses. Accordingly, more emphasis has been given to the task of improving the efficiency of order picking systems in general, and the required traveled distance during the order picking operation, specifically.
In this thesis, we focus on two main factors that significantly affect the efficiency of order picking systems: the assignment storage policies, including the full-turnover, nearest-location and random storage policies; and the warehouse layout structure, in terms of the depth and the number of storage aisles. We investigate the combined effects of these two factors on the order picking travel distance.
While previous research compares the full-turnover to the random storage policy, we compare the performance of the full-turnover policy to the nearest-location and random storage policies over various warehouse layout alternatives.
For this purpose, we present a methodology for estimating order picking travel distance in a single-block, open-ended warehouse, under the assumptions of S-shape routing and discrete order policies.
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Hung, Ming-Chuan, and 洪明傳. "A Study of Efficient Data Warehouse and Data Mining Techniques." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/70389186760743577809.
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博士逢甲大學
資訊工程所
94
Data mining deals with the discovery of hidden knowledge, unexpected patterns, and new rules from large databases. It is currently regarded as the key element of a much more elaborate process called knowledge discovery in databases (KDD), which is closely linked to another important development, data warehousing. The combination of data warehousing, decision support, and data mining indicates an innovative and totally new approach to information management. In this dissertation, we concentrated on research for this newly emerging field. We investigate three majors portions of the mining process and warehousing, one presents data warehousing with optimal utilization of materialized views, another proposes a novel algorithm to mining association rules using merged transactions approach, and the other presents an efficient algorithm to implement a k-means clustering and proposes an efficient algorithm, namely spFCM for fast fuzzy clustering. View materialization is an effective method to increase query efficiency in a data warehouse and improve OLAP query performance, providing the basis for integration with a data mining process. However, one encounters the problem of space insufficiency if all possible views are materialized in advance. Reducing query time by means of selecting a proper set of materialized views with a lower cost is crucial for efficient data warehousing. In addition, the costs of data warehouse creation, query, and maintenance have to be taken into account while views are materialized. In this study, efficient algorithms are proposed to select a proper set of materialized views, constrained by storage and cost considerations, to improve performance of the entire data warehousing process. Also, a cost model for data warehouse query and maintenance is derived to effectively exploit the gain and loss metrics in the use of efficient view selection algorithms. The main contribution of the proposed approach is to dramatically improve the efficiency of the selection process of materialized views, thereby greatly reducing the overall cost of data warehouse query and maintenance. Mining association rules among sets of items in a large database has been widely investigated. In the Apriori-like algorithms, transactions are not stored in memory and multiple database scans are required; this approach is computationally more expensive. A different approach is proposed in this study, based on the use of three data preprocess methods, to group transactions in a database and devise an efficient algorithm to mine association rules from the merged transactions with much better performance. The first data preprocess method sorts transactions to classify the groups. The other two approaches use a simplified dynamic programming algorithm to merge transactions. Compared with other algorithms, our proposed method performs much better with less I/O overhead. The experimental results show that after preprocess only one scan of a database is required in the data mining stage to generate association rules. In addition, the proposed method is especially suitable for very large databases and can be applied in an incremental fashion. The k-means algorithm is one of the most widely used methods to partition a dataset into groups of patterns. However, most k-means methods require expensive distance calculations for centroids to achieve convergence. This study presents an efficient algorithm to implement a k-means clustering that produces clusters comparable to other methods with lower computational cost. In the proposed algorithm, the original dataset is partitioned into blocks; each block unit, called a Unit Block (UB), contains at least one pattern. The centroid of a unit block (CUB) can be located by using a simple calculation. All the computed CUBs form a reduced dataset that represents the original dataset. The reduced dataset of CUBs is then used to compute the final centroid of the original dataset. Only each UB on the boundary of candidate clusters needs to be examined to find the closest final centroid for every pattern in the UB. In this way, it is possible to dramatically reduce the time for calculating final converged centroids. Experimental results indicate that this algorithm produces compatible clustering results produced by other k-means algorithms, but with much less computational cost. The fuzzy c-means (FCM) algorithm, commonly used for clustering, can provide a data partition that is better and more meaningful than hard clustering approaches. The performance of the FCM algorithm depends on the selection of an initial cluster center and/or its initial membership value. If a good initial cluster center is found close to the actual final cluster center, the FCM algorithm will converge very quickly and the processing time can be drastically reduced. We propose a novel algorithm based on the FCM clustering, which significantly reduces the required computation time by using a simple partitioning approach. In the first phase of the proposed algorithm, called spFCM, a reduced dataset is derived from the original source dataset to estimate the initial cluster centers, which are used in the second phase to find the actual cluster centers. It is possible to empirically evaluate the performance of the spFCM algorithm using synthetic datasets that exhibit varying cluster sizes and distributions. Observations of the use of synthetic datasets indicate that the proposed spFCM algorithm is on an average five times faster than the original FCM algorithm. Additionally, the quality of the proposed spFCM algorithm is compatible with that of the FCM algorithm.