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Optimalizace logistického toku v podniku / OPTIMALIZATION OF LOGISTIC FLOWS IN THE ENTERPRISEDvořáček, Radim January 2009 (has links)
The dissertation is concerned about, according to author still “live” problem of optimization of logistic flow, with scope to company environment. The aim is to find correct methodology for defined problem and to apply it to particular case study. Theoretical part begins with description and analysis of actual state of problematic of logistic flow optimization and listing the methods which are able to be applied to these problems. The three main groups – exact methods, heuristic methods and combined methods take part in. The analysis continues further with searching the methods, useful for application in production company environment. Vast focus is on layout design task, because once layout is created, except some minor changes, it lasts usually for some years and therefore it is necessary to consider it properly. Moreover, there is also difference between other characteristics of production, as production planning and machines / technologies upgrade and layout; the former are in a certain manner changeable and not stable, but the layout cannot be changed on for ex. weekly basis. Contribution to research is located at the end of theoretical part, which is newly modified methodology to be more suitable for practical application. Practical part begins with the description of particular case study, e.g. actual status of logistic system in enterprise. The processes described include purchasing management, production management and mainly layout design of production space. The application of suitable methods consists of group technology methods – already known method, plus newly modified method and their mutual comparison. In addition is included already known value stream mapping method. The result is recommendation for change in layout design, developed by integration of results, brought by group technology methods and value stream mapping method.
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Materiálové toky a environmentální dopady malého elektroodpadu / Material Flows and Environmental Impacts of s-WEEE in the Czech RepublicPolák, Miloš January 2015 (has links)
This thesis is a comprehensive study describing and quantifying material flows of waste electric and electronic equipment (WEEE) in the Czech Republic; specifically the material flow of small waste electric and electronic equipment (s-WEEE) as well as representative substances. The studied material flows were estimated regarding aspects of the environmental impact. The End-of-Life mobile phone is seen as a typical representative of s-WEEE ; therefore material flows of mobile phones are described in this thesis as well. To put it in concrete figures, approximately 124 thousand tons of WEEE from households originated in the Czech Republic in 2010, where each inhabitant got rid off 4 pieces of WEEE in average. Further, total production calculating also consumer-like WEEE from companies and institutions was around 141 thousand tons in 2010. S-WEEE present around 15% from the total amount of WEEE originating in 2010; however it is more than 80% as regards the number of pieces. Despite of that fact the recycling potential of Au for instance is slightly higher by s-WEEE than by large WEEE (63kg/year compared to the 59kg/year respectively). As regards estimation of the total production of EoL mobile phones, around 45 thousand pieces originated in the Czech Republic between the years 1990-2000 and 6,5...
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Investigation of Jamming Phenomenon in a DRI Furnace Pellet Feed System using the Discrete Element Method and Computational Fluid DynamicsJohn Gregory Rosser (15448535) 11 May 2023 (has links)
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<p>Direct reduction ironmaking has gained popularity as a low carbon alternative to the typical blast furnace ironmaking route. A popular method of producing direct reduced iron is through the reduction of iron ore pellets in a reduction shaft furnace. Critical to this process is the use of a reliable continuous pellet feed system to provide a steady flow of pellets to the furnace. Therefore, any disruption in pellet flow can have a significant negative impact on the production rate of iron. </p>
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<p>An iron ore pellet feed system for a direct reduction ironmaking furnace is jamming during winter operation. The pellets are jamming in a hopper at the top of the feed system above the furnace, and a hot gas, that seals off the furnace flue gas, flows counter to the pellets. A computational model of the feed system is built utilizing the discrete element method and computational fluid dynamics, using Siemen’s commercial multiphysics software Star-CCM+, to study the conditions that cause the jam to occur. The study is divided into six parts: pellet bulk flow calibration, computational cost reduction, modeling of the baseline operation, modeling the effect of moisture, development of a thermal model, and investigation of the minimal amount of icy and wet material to jam the system. The findings show that the location of jamming during operation matches the area in the simulation where it is most likely to occur, and that moisture alone is unlikely to result in jamming. Results indicate that the system will jam when charged with a minimum of 15% icy pellets, and when charged with 10% icy together with 5% wet pellets. Experimental work is recommended to validate the findings and to calibrate the simulations accordingly.</p>
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Effektivisering av reservdelsflödet mellan OEM och centrallager : En fallstudie om materialflödet av reservdelar mellan tillverkande företags originaltillverkare (OEM) och centrallager / Streamlining the flow of spare parts between OEM andcentral warehouseEricsson, Mathilda, Eriksson, Viktor January 2023 (has links)
Syfte - Sjunkande marginaler hos primärprodukter har riktat ökad uppmärksamhet mot den lönsamma reservdelsverksamheten. Det finns dock utmaningar kring flödet av reservdelar, bland annat i) teoretiskt gap kring flödet av reservdelar, ii) behovet att effektivisera flöden av reservdelar, och iii) avsaknad av praktisk arbetsprocess. Med bas i dessa utmaningar har studiens syfte formulerats till ”Att utforma en arbetsprocess för effektivare materialflöde av reservdelar mellan OEM och centrallager för tillverkande företag”. Genom att identifiera och analysera effektivitetsvariabler som påverkar flödet av reservdelar, har en praktiskt tillämpbar arbetsprocess skapats för att effektivisera försörjningskedjan och fylla kunskapsgapet inom området. Metod - Denna studie är av typen enfallsstudie, som undersöker materialflödet av reservdelar och arbetsprocesser inom logistik. Data samlades in genom intervjuer och dokumentstudier för att identifiera effektivitetsvariabler. Studien kombinerar teori och empiri för att erhålla djupare förståelse av fallet och strävar efter att dra slutsatser och ge insikter som kan tillämpas inom logistikområdet i allmänhet. Resultat - Resultatet av studien redovisas en arbetsprocess som har utformats för att effektivisera materialflödet av reservdelar mellan OEM och centrallager. Genom att ha identifierat effektivitetsvariabler har studien prioriterat de variablerna med störst förbättringspotential. En arbetsprocess har utvecklats med konkreta förslag på förbättringar för att minska avstånd, kostnader och ledtider till centrallagret. Resultaten ger insikter om hur materialflödet kan effektiviseras mellan OEM och centrallager hos tillverkande företag. Implikationer - Resultatet av studien fyller kunskapsgapet genom att undersöka reservdelsflödet och dess koppling till effektivisering av försörjningskedjor. Genom att ha identifierat effektivitetsvariabler bidrar studien till ökad förståelse för hur företag kan effektivisera hanteringen av reservdelar. Studien adresserar viktiga utmaningar inom reservdelsförsörjningen genom att erbjuda praktiska lösningar och insikter till beslutsfattare för att skapa effektiva materialflöden. I studien har en arbetsprocess skapats, vilket kan hjälpa företag att effektivisera dess reservdelsflöden och undvika onödig resursförbrukning. Resultatet av studien kan fungera som en vägledning för företag som strävar efter att förbättra sitt materialflöde av reservdelar och öka sin övergripande effektivitet. Begräsningar - Studiens begränsningar är att enbart en enfallsstudie har utförts. Dessutom behandlas endast det materialflöde uppströms mellan OEM och centrallager som utgörs av det utvidgade försörjningskedjan. Därav undersöks inte materialflödet nedströms mot slutkund. / Purpose - Falling margins in primary products have directed increased attention to the profitable spare parts business. However, there are challenges around the flow of spare parts, including i) theoretical gap around the flow of spare parts, ii) the need to streamline the flow of spare parts, and iii) lack of practical work process. Based on these challenges, the purpose of the study has been formulated as "To design a work process for more efficient material flow of spare parts between OEM and central warehouse for manufacturing companies". By identifying and analyzing efficiency variables that affect the flow of spare parts, a practically applicable work process has been created to streamline the supply chain and fill the knowledge gap in the field. Method - This study is of the single-case study type, which examines the material flow of spare parts and work processes in logistics. Data were collected through interviews and document studies to identify efficiency variables. The study combines theory and empiricism to obtain a deeper understanding of the case and aims to draw conclusions and provide insights that can be applied within the field of logistics in general. Findings - The result of the study is a work process that has been designed to streamline the material flow of spare parts between the OEM and the central warehouse. By having identified efficiency variables, the study has prioritized those variables with the greatest potential for improvement. A work process has been developed with concrete proposals for improvements to reduce distance, costs, and lead-times to the central warehouse. The results provide insights into how the material flow can be made more efficient between the OEM and the central warehouse of manufacturing companies. Implications - The result of the study fills the knowledge gap by examining the flow of spare parts and its connection to the efficiency of supply chains. By having identified efficiency variables, the study contributes to increased understanding of how companies can streamline the handling of spare parts. The study addresses important challenges in spare parts supply by offering practical solutions and insights to decision makers to create efficient material flows. In this study, a work process has been created, which can help companies to streamline their spare parts flows and avoid unnecessary resource consumption. The result of the study can serve as a guide for companies that strive to improve their material flow of spare parts and increase their overall efficiency. Limitations - The study's limitations are that a single case study has been carried out. In addition, only the upstream material flow between the OEM and the central warehouse that constitutes the extended supply chain is treated. As a result, the material flow downstream towards the end customer is not investigated.
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Avfall eller resurs? En prognos över framtida behandling av restavfall och organiskt avfallHenriksdotter Langer, Lina January 2015 (has links)
Studien gjordes som ett avslutande moment i den miljövetenskapliga utbildningen vid Malmö högskola. Ämnet valdes i samarbete med NSR i Helsingborg och syftade till att utreda restavfallets framtida innehåll av organiskt material i några nordvästskånska kommuner. Avfallet som inkommit till Filborna i Helsingborg kartlades med hjälp av en materialflödesanalys för att synliggöra materialflödena till och från samt inom anläggningen. Målet med studien var att undersöka om det även i fortsättningen kommer att vara bäst att behandla restavfallet biologiskt eller om det i större utsträckning kommer innehålla brännbart material och därmed kommer vara lämpligare att energiåtervinna restavfallet. På grund av det varierande antalet hushåll sin källsorterar organiskt material i de olika kommunerna var det en svårighet att göra en korrekt bedömning och resultaten grundades på antaganden om hur källsorteringsgraden kommer att förbättras framöver. Resultatet baseras på statistik från 2002-2006 och en prognos fram till och med år 2014 visar på att med dagens hastighet dröjer det ytterligare 19 år från 2014 innan restavfallet består enbart av brännbart material. Det sker hela tiden förbättringar på området i regionen vilket innebär att resultatet kan komma att variera mycket vilket också innebär att tidsprognosen kan komma att kortas ner med tiden. / The study was made as a final exam in Environmental Science at Malmö högskola. The subject was chosen in co operation with a few of the work force at NSR in Helsingborg and was aiming to investigate the future substance of organic waste in a northwest region in Skåne, Sweden. The waste which is taken care of at Filborna in Helsingborg was mapped out with a material flow analysis due to reveal the flows of materials to and from the construction. The aim with the study was to investigate whether the biological treatment still will be the most optimal solution in the future or if the solid waste will contain only flammable material and thereby the optimal solution will be energy recycling. Due to the varying amount of households which are sorting their organic wadte there were diffuculties to make correct estimates and thereby the results are founded on assumptions. The results are based on statistic material 2002-2006 and a forecast until 2014. They show that it will take another 19 years before the solid waste compound only flammable material. However recycling keeps improving and the forecast will shorten in time.
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Environmental Assessment of Kayak using MFA & LCA : A case study at Melker of Sweden / Miljöbedömning av Kajak med hjälp av MFA & LCA : En fallstudie genomförd i samarbete med Melker of SwedenSrivastav, Abhishek, Xenos, Spyridon January 2020 (has links)
Kayaking is a watersport activity that involves paddling performed within leisure purposes. Although kayaking provides pleasure to the practitioners, there are some adverse environmental issues concerning the site used to perform kayaking due to the equipment. This paper identifies and analyzes the lifecycle stages in which negative environmental impacts are generated. Melker of Sweden is an outdoor company specialized in delivering high-quality kayaks. This study aims to present an overview of the current environmental performance of Melker of Sweden’s kayaks. For this purpose, two environmental assessment tools are applied: material flow analysis and life cycle assessment. The Material Flow Analysis (MFA) results show that the transport of material to the manufacturing unit generates a considerable amount of emissions. Additionally, hull manufacturing and assembling accessories were found to be the least resource-efficient operation among all. The Life Cycle Assessment (LCA) results identify the transport of material and the manufacturing phase as the primary sources responsible for environmental impacts. On the one hand, the use of epoxy resin and gel coat is the root cause of high contribution of the manufacturing phase. On the other hand, the use of flax fiber found to be the least contributing material to adverse environmental impacts. This report also presents a list of recommendations regarding the import of material, the efficacy of the manufacturing operations, the type of raw material, and waste treatment alternatives. / Fysisk aktivitet kan innefatta olika fritidsaktiviteter, däribland friluftsliv. Kajakpaddling är en sådan friluftslivaktivitet, alltefter utövares syfte. I denna rapport är kajakpaddling en fritidsaktivitet där där utövarens naturupplevelse främjas. Oaktat fördelarna vid utövandet av denna aktivitet kan ej förbises faktum att det också kan medföras vissa negativa konsekvenser. Denna masteruppsats har som mål att identifiera och analysera den miljöpåverkan och dennes efterspel som orsakats av en kajaks tillverkning. Melker of Sweden är ett utomhusföretag specialiserat på att leverera kajaker av hög kvalitet. I linje med företagets vision syftar denna studie till att undersöka den nuvarande miljöprestandan samt kvantifiera den potentiella miljöpåverkan från en kajaks livscykel. För detta ändamål tillämpas det två miljöbedömningsverktyg, nämligen en materialflödesanalys och livscykelanalys. Materialflödesanalysen visar att mängden av utsläpp som genereras från transporten av material till tillverkningsenheten är enorm. Utöver detta var den hulltillverkning samt den montering av tillbehörsverksamheter bland de minst resurseffektiva tillverkningssteg. Livscykelanalysen identifierar import av material och tillverkningsfas som de viktigaste källorna till miljöpåverkan. Å ena sidan är användningen av epoxiharts och gelbeläggning i tillverkningen grundorsaken till huvudbidraget. Å andra sidan är användningen av linfiber det minst bidragande material då det gäller negativa miljöeffekter. I denna studie ges rekommendationer rörande import av vissa material och materialval, sätt att öka tillverkningseffektiviteten, typ av råmaterial samt avfallsbehandlingsalternativ.
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Improving the Material Flow Through Just-In-TimeAlhaj, Jasmin, Darman, Raiman January 2024 (has links)
ABSTRACT Date: 2nd June 2024 Level: Master thesis in Product and Process Development, advanced level, 30 credits Institution: School of Innovation, Design and Engineering, Mälardalen University Author: Raiman Darman, 25th April 2000, Jasmin Alhaj, 12th Mars 1998 Title: Improving the Material Flow through Just-in-time Tutor: Ola Wassenius & Oliver Söderlund, ABB Robotics, Mats Ahlskog, Mälardalen University Keywords: Material flow, Just-in-time, Lean production, Warehouse management system Purpose: The purpose of this master thesis is to explore how Just-in-time principles can be applied to improve the internal material flow and to identify necessary functionalities in the warehouse management system to support Just-in-time. Research questions: Q1: How can the material flow in production systems be improved by implementing Just-In-time? Q2: What type of functionality is needed in the warehouse management system to support Just-in-time? Method: This study employs qualitative research and an abductive approach to achieve its objectives. Data collection is categorized into secondary research, involving a review of existing literature, and primary research, which includes a case study conducted through interviews and observations. Both semi-structured and unstructured interviews were employed with the case company and the benchmarking organization. The use of benchmarking allows for the comparison of organizational practices, challenges, and outcomes, aiding in identifying areas for improvement and gaining insights into effective strategies. Conclusion: Addressing the first research question, the material flow can be improved by transitioning to a pull-based system and implementing concepts such as supermarkets and point-of-use storage. Furthermore, integrating automated systems for tracking cart availability and establishing clear protocols for standardized work procedures are crucial. Real-time communication and coordination between departments, facilitated by advanced solutions like real-time visibility screens, are also ways of improving the material flow. Addressing the second research question, it's critical to integrate the internal WMS with the SAP ERP software, address communication gaps, provide comprehensive user training and support, streamline task sequencing, and conduct regular system updates and maintenance. / SAMMANFATTNING Datum: 2 juni 2024 Nivå: Examensarbete i produkt- och processutveckling, avancerad nivå, 30 hp Institution: Akademin för Innovation, Design och Teknik, IDT, Mälardalens universitet Författare: Raiman Darman, 25 april 2000, Jasmin Alhaj, 12 mars 1998 Titel: Förbättra materialflödet genom Just-in-time Handledare: Ola Wassenius & Oliver Söderlund, ABB Robotics, Mats Ahlskog, Mälardalens Universitet Nyckelord: Materialflöde, Just-in-time, Lean production, lagerhanteringssystem Syfte: Undersöka hur Just-in-time-principer kan tillämpas för att förbättra det interna materialflödet och att identifiera nödvändiga funktioner i lagringshanteringssystemet för att stödja Just-in-time. Frågeställningar: F1: Hur kan materialflödet i produktionssystemen förbättras genom att implementera Just-in-time? F2: Vilken typ av funktionalitet behövs i lagerhanteringssystemet för att stödja Just-in-time? Metod: Denna studie använder kvalitativ forskning och en abduktiv metod för att uppnå sina mål. Datainsamlingen kategoriseras i sekundär forskning, med en genomgång av befintlig litteratur, och primär forskning, som inkluderar en fallstudie genomförd genom intervjuer och observationer. Både semistrukturerade och ostrukturerade intervjuer används med caseföretaget och benchmarkingorganisationen. Användningen av benchmarking gör det möjligt att jämföra organisatoriska metoder, utmaningar och resultat, vilket hjälper till att identifiera områden för förbättringar och få insikter i effektiva strategier. Slutsats: Genom att ta itu med den första forskningsfrågan kan materialflödet förbättras genom att gå över till ett pull-baserat system och implementera koncept som stormarknader och point-of-use. Dessutom är det avgörande att integrera automatiserade system för att spåra vagnens tillgänglighet och upprätta tydliga protokoll för standardiserade arbetsprocedurer. Kommunikation i realtid och koordinering mellan avdelningar, underlättat av avancerade lösningar som skärmar i realtid, är också sätt att förbättra materialflödet. För att ta itu med den andra forskningsfrågan är det viktigt att integrera det interna WMS med SAP ERP-programvaran, åtgärda kommunikationsluckor, tillhandahålla omfattande användarutbildning och support, effektivisera uppgiftssekvenseringen och genomföra regelbundna systemuppdateringar och underhåll.
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L'économie circulaire appliquée à un système socio-écologique halio-alimentaire localisé : caractérisation, évaluation, opportunités et défis / Circular economy in a small-scale fishery-dependent socio-ecological system : characteristics, evaluation, opportunities and challengesLe Gouvello, Raphaëla 01 March 2019 (has links)
L'économie circulaire (EC) émerge depuis les années 2000 dans le débat public, en opposition à l'économie linéaire, modèle dominant aux limites économiques et écologiques reconnues. Cette thèse constitue une première confrontation opérationnelle de l'EC à un système socio-écologique dépendant de la pêche, le Pays de la Cornouaille en Bretagne. Le système est délimité dans sa façade maritime avec la pêche côtière, seule considérée comme production locale.L'approche est systémique, multidimensionnelle et dynamique. L'analyse comporte trois volets : le premier sur l'amont du circuit en mer, le deuxième sur l'aval du système à terre et le dernier sur le système complet. Premièrement, le coût caché des rejets est visualisé via une analyse comptable de flux de matière ("Material Flow Cost Accounting" MFCA) adaptée à la pêche, proposé comme outil pertinent pour améliorer la performance économique et environnementale des pêcheurs. Deuxièmement, l’analyse de flux révèle une forte dépendance des activités à terre vis-à-vis des importations et exportations de bioressources halieutiques malgré un apport significatif de la pêche côtière à l'économie locale. Troisièmement, des scenarii sur le sous-système Sardine, du "business as usual" a l'EC, servent à proposer une trajectoire alternative de développement basée sur un "panier" de biens et services territorialises et la construction d'une valeur territoire à partir de ressources halieutiques locales. Pour atteindre cette EC durable, il s'agira d'optimiser l'utilisation des ressources locales et diminuer les externalités négatives, en plus d'aller vers une gouvernance partagée, adaptée à l'échelle du système socio-écologique considéré. / The years 2000 have favored the emergence of "Circular Economy" (CE) in the public debate, as opposed to the "linear economy", the dominant model that led to acknowledged economie and ecological limits. Our work is a first attempt to address the CE to a fishery-dependent socio-ecological System, the Cornouaille region in Brittany. The approach is systemic, multidimensional and dynamic. It implies the identification of marine boundaries, in which only Coastal fisheries are considered as a local production. The analysis is conducted along three main axes: an analysis of the upstream part at sea (fishing), an analysis looking at the downstream value chain, on land, and a third looking at the whole System. First, a Material Flow Cost Accounting (MFCA) analysis adapted to fisheries is proposed as a relevant tool to improve economy and environmental performance of fishers, providing evidence of hidden costs of fish discards.Second, the fish bioresource flow analysis indicates a strong dependency on importation and exportation flows to maintain land-based activities depending on sea products, albeit evidence of a significant contribution of Coastal fisheries to the local economy. Third, the exploration of the sardine sub-system through scenarii, ranging between from "business as usual" to those lined with CE, shows an alternative development trajectory, based upon a potential "basket of goods and services", a "territorial value", specifically linked to local fisheries. To achieve such a sustainable CE, we would need to not only aim at a more efficient use of local marine resources and decrease negative externalities, but also advocate for a shared governance, suited to the scale of the considered localised socio-ecological System.
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Etude de la dynamique hydro-sédimentaire de fleuves tropicaux par mesures in situ et de télédétection : le cas du Maroni, de l'Oyapock et de l'Orénoque / Study of the hydro-sedimentary dynamics of tropical rivers by measures in situ and remote sensing : the case of the Maroni, Oyapock and OrinocoGallay, Marjorie 17 October 2017 (has links)
L'eau des fleuves, des rivières, des lacs et des réservoirs ne représente que 0,26 % des 2,5 % (35 millions de km3) d'eau douce disponibles à l’état liquide sur Terre, or sa qualité et quantité ont fortement diminué ces dernières années. Sa dégradation a des conséquences sur l'agriculture, la santé, l'environnement et l'économie des territoires et est aujourd'hui au centre des préoccupations sociétales. Les objectifs de la présente thèse sont pour trois fleuves localisés dans le Bouclier des Guyanes, au nord de l'Amérique du Sud (le Maroni, l'Oyapock, l'Orénoque): (i) d'utiliser et d'adapter des outils novateurs de télédétection pour suivre et quantifier, sur du long terme, leurs charges sédimentaires en suspension, (ii) d'évaluer l'existence de tendances spatio-temporelles, ainsi que de ruptures dans les chroniques de données, (iii) de quantifier la part organique et minérale de ces charges, (iv) d'apprécier le rôle des facteurs naturels (débits et précipitations) et anthropiques (surfaces urbaines, agricoles et minières) sur les tendances observées et enfin, (v) de discuter de seuils de charges pour le suivi de la qualité de l'eau. Les résultats ont montré qu'il est possible de suivre les concentrations de matières en suspension, pour les fleuves Orénoque et Maroni avec une erreur relative de 32 et 25% respectivement. Sur la période 2000-2016, des tendances spatio-temporelles régulières ont été observées pour l'Orénoque, alors qu'elles sont en augmentation pour le Maroni avec une rupture en 2009 et en diminution pour l'Oyapock depuis 2008 (données in situ). Un lien fort avec l'augmentation de la déforestation pour les surfaces minières et les précipitations est observé pour le Maroni alors que pour l'Oyapock les tendances sont liées aux débits.Pour les deux années d'études (2014-2016), les charges minérales ont représenté la plus forte fraction des particules transportées dans les eaux du Maroni au Saut Hermina (en moyenne 93 %) et de l'Oyapock au Saut Maripa (en moyenne 82 %) avec une grande variabilité selon les mois de la teneur en carbone dans les matières transportées et pour les deux fleuves. Enfin, les rapports C/N et C/Chl-a ont dévoilé des matières organiques d'origine principalement endogène avec une forte biomasse chlorophyllienne surtout durant les basses eaux. / The water of rivers, lakes and reservoirs represents only 0.26 % of the 2.5 % (35 million of km3) of fresh water available on the liquid state on Earth, but its quality and quantity strongly decreased these last years. Her degradation has consequences on the farming, the health, the environment and the economy of territories and is now in the center of the societal concerns. The objectives of the present thesis are for three rivers located in the Guiana Shield, in the North of South America (the Maroni, the Oyapock, the Orinoco): i) to use and to adapt innovative tools of remote detection to follow and quantify, on the long term, their sedimentary loads, ii) to estimate the existence of spatiotemporal trends, as well as breaks in the chronicles of data, iii) to quantify the organic and mineral part of these loads, iv) to appreciate the role of the natural (discharge and precipitation) and the anthropological factors (urban, agricultural and mining surfaces) on the observed trends and finally, v) to discuss thresholds of concentrations for the quality monitoring of the river water.The results showed that it is possible to follow the concentrations of suspension materials, for rivers Maroni and Orinoco with a relative error of 25 and 32 % respectively. Over the period 2000-2016, regular spatiotemporal trends were observed for the Orinoco, while they are increasing for Maroni with a break in 2009 and in decrease for the Oyapock since 2008 (in situ data). A strong link with the increase of the deforestation for the mining surfaces and the precipitation is observed for the Maroni catchment while for the Oyapock the trend is explained by the specific water discharge.For two years of studies (2014-2016), the mineral loads represented the strongest fraction of particles transported in the Maroni River at Saut Hermina (on average 93 %) and in the Oyapock River at Saut Maripa (on average 82 %) with a high variability according to the months of the content in carbon in the transported materials and for both rivers. Finally, report C/N and C/Chl-a revealed organic matters of mainly endogenous origin with a strong chlorophyll biomass and especially during the low water period.
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Design of an Assembly System at AERCRETE INDUSTRIESHansson Tengberg, Henrik, Adlerborn, Andreas January 2009 (has links)
The forming of an assembly system is a complex task, which should be considered as never ending. In order to successfully plan and implement an assembly system it is of vital importance that the obstacles and preconditions that have an impact on the system are identified and evaluated. This together with the necessary support activities and the attributes of the product to be assembled constitutes the starting point for the forming of the assembly system. The aim of this thesis is to link the theoretical findings with the issues stated above, and through this explain a best practice approach when forming the assembly system. The theoretical work aims at describing the nature and activities within assembly and manufacturing systems and explains these in three different levels of strategies divided into Manufacturing strategies, Layout, material flow and design strategies and finally Logistic, material handling and quality strategies. Then the obstacles and preconditions found are discussed and evaluated which set the basis for the forming of the assembly system and by linking these with the relevant theory, conceptual design proposals for the assembly system and the Logistic support system are formed. These are then evaluated and finally a proposal for the detailed layout of the assembly system is given. This proposal is then to be used as a guideline for the company Aercrete when forming their assembly system.
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