Дисертації: "Indicators of the material flow"

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Eisenmenger, Nina, Dominik Wiedenhofer, Anke Schaffartzik, Stefan Giljum, Martin Bruckner, Heinz Schandl, Thomas Wiedmann, Manfred Lenzen, Arnold Tukker, and de Koning Arjan. "Consumption-based material flow indicators - Comparing six ways of calculating the Austrian raw material consumption providing six results." Elsevier, 2016. http://epub.wu.ac.at/6684/1/ECOLEC.pdf.

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Understanding the environmental implications of consumption and production depends on appropriate monitoring tools. Material flow accounting (MFA) is a method to monitor natural resource use by countries and has been widely used in research and policy. However, the increasing globalization requires the consideration of "embodied" material use of traded products. The indicator raw material consumption (RMC) represents the material use - no matter where in the world it occurs - associated with domestic final demand. It provides a consumption-based perspective complementary to the MFA indicators that have a territorial focus. Several studies on RMC have been presented recently but with diverging results; hence, a better understanding of the underlying differences is needed. This article presents a comparison of Austrian RMC for the year 2007 calculated by six different approaches (3 multi-regional input-output (MRIO) and 3 hybrid life-cycle analysis-IO approaches). Five approaches result in an RMC higher than the domestic material consumption (DMC). One hybrid LCA-IO approach calculates RMC to be lower than DMC. For specific material categories, results diverge by 50% or more. Due to the policy relevance of the RMC and DMC indicators it is paramount that their robustness is enhanced, which needs both data and method harmonization.

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González, Martínez Ana Citlalic. "Social metabolism and patterns of material use Mexico, South-America and Spain." Doctoral thesis, Universitat Autònoma de Barcelona, 2008. http://hdl.handle.net/10803/5812.

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La presente tesis se compone de tres artículos publicados y uno enviado para publicación. Son cuatro casos de estudio que comparten el mismo eje teórico: el metabolismo social. Usando la metodología Contabilidad de Flujos de Materiales se han medido las entradas de materiales de varias economías. Los indicadores que se obtienen aplicando esta metodología permiten caracterizar los perfiles metabólicos de las economías estudiadas, identificando los factores más importantes que los determinan. Asimismo, estos indicadores pueden considerarse como una medida indirecta de la presión que una economía ejerce en el medio ambiente. Por otra parte, esta tesis tiene como objetivo dar evidencia empírica sobre la ausencia de desmaterialización de las economías. La principal conclusión es que en este mundo globalizado, los países son cada vez más dependientes del comercio internacional y el papel que un país juega en el concierto internacional determina en gran medida la manera como utiliza sus recursos materiales. Sin embargo, esta dependencia sigue diversas trayectorias. Por una parte, identificamos un conjunto de países como España que se ha beneficiado de este proceso. En las últimas dos décadas, este país ha logrado aumentar su bienestar económico usando intensivamente recursos provenientes de otros sistemas socioeconómicos, como el petróleo. Sin embargo, el principal factor determinante de su perfil biofísico ha sido el sector de la construcción. Por otra parte, identificamos aquellos países que históricamente han basado sus economías en la extracción de recursos naturales como Chile, Ecuador, México y Perú y que actualmente no presentan un patrón uniforme de uso de recursos naturales. En Ecuador, Chile y Perú, el comercio internacional ha sido el principal determinante del patrón e intensidad del uso de los recursos naturales. Sin embargo, Ecuador sigue siendo el ejemplo típico de economía extractiva mientras que Chile ha logrado una diversificación de sus exportaciones con mayor valor agregado. Este proceso se observa pero de manera muy incipiente en Perú. Chile puede considerarse como el ejemplo más exitoso en la región del modelo basado en exportaciones de materias primas al lograr un fuerte crecimiento económico. México es un caso especial y contradictorio, porque a pesar de ser un importante exportador de petróleo, ha logrado una diversificación de su producción hacía sectores con un mayor componente tecnológico debido a la creciente presencia de la industria maquiladora. Sin embargo, no son sus flujos de exportaciones ni el crecimiento económico los principales determinantes del uso que hace de sus recursos materiales sino el crecimiento de la población. Por otra parte, se observa un incremento considerable en el uso de materiales de construcción y energéticos fósiles en toda la economía mientras que al mismo tiempo, la población rural sigue dependiendo de fuentes tradicionales de energía como la leña para satisfacer sus necesidades energéticas. Otra conclusión general es que no se observa un proceso de desmaterialización ni absoluta ni relativa en ninguno de los países analizados.
This thesis is composed of three published articles and a submitted one. All share the same theoretical approach: social metabolism. By tracing all material flows into several economic systems by means of the Material Flows Accounting methodology (MFA), this thesis aims on the one hand at characterizing current metabolic profiles of different economies, identifying their main driving forces; on the other hand, it aims at providing empirical evidence on dematerialisation of the economies. The main conclusion is that in our globalised world, countries are becoming more dependent on international trade and that the role a country plays in the international markets strongly determines its pattern of material use. This dependency followed different trajectories. On the one hand, we identify countries such as Spain that benefited from this process as it increased welfare based in an intensive use of strategic natural resources coming from other economic systems such as fossil fuels. Nevertheless, the main driving force shaping the biophysical profile of this economy was the construction sector, an internal factor. On the other hand, we identify those countries that historically have relied on the extraction of natural resources such as Chile, Ecuador, Mexico and Peru although we can no longer talk about a uniform pattern of natural resource use in the region. In Ecuador, Chile and Peru, international trade was the main driving force for material use. Ecuador remains the typical example of an extractive economy whereas a diversification of exports away from bulk commodities towards products with more added value could be observed to a greater extent in Chile and incipiently in Peru. Chile can be regarded as a successful example of the staple theory of growth as its GDP increased considerably. Mexico is a special and contradictory case. Firstly, despite being an important oil exporter, it has achieved a diversification of production, moving towards technology-intensive products due to the assembly industries. Secondly, despite it has a great potential of biomass extraction, it is undergoing a substitution process of imported biomass for national biomass, in particular, basic crops for human consumption. Instead of international trade, population growth was the main driving force for biophysical growth in this economy. Thirdly, it was observed an increasing emphasis on the use of construction materials and fossil fuels in the whole economy whereas in the countryside, rural households still rely heavily on traditional biomass flows such as fuelwood to satisfy their energetic needs. A general conclusion is that neither absolute dematerialisation nor relative dematerialisation occurred in any of the analysed countries.

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Piñero, P. (Pablo). "The metabolism of socio-economic systems:combination of input-output analysis and material flow accounting for footprint-type indicators." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526224848.

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Abstract This thesis explored innovative ways to improve estimation of material footprint-type indicators in application of Input-Output (IO) analysis to Material Flow Accounting. The following six research questions were addressed: 1) What is the potential impact of sector aggregation in IO modelling of raw material flows? Modelling errors due to aggregation of industries with dissimilar material requirements and trade structures into a single sector in IO models when calculating the material footprint were empirically analysed relative to greenhouse gas emissions. Significant biases emerged for raw material flows, which suggests that care should be taken when aggregating extractive sectors in IO models. 2) Can bottom-up approaches, such as LCA (Life Cycle Assessment), improve estimation of the raw materials embodied in trade products? and 3) What are the implications of integration of country-specific information from high geographical coverage IO models into LCA approaches for calculation of raw material embodied in trade products? An approach for combining country-specific production blueprints with LCA based on regional averages was developed. This approach proved useful in refining estimates of upstream raw materials embodied in trade products, although care is needed during its application since new biases may arise. 4) Can further perspectives be gained with a new allocation method, the ‘value added-based material footprint’, which assigns supply chain-wide raw material extractions to each participating economic actor according to its added value generation, contributing to discussions on the distribution of mitigation costs? Certain countries and sectors were found to be more material-intensive with this new accounting approach than in other widely known allocation methods, e.g. consumer footprint. 5) Are there unequal exchanges between high-income economies and middle- and lower-income countries when measured in terms of raw material and value added flows? and 6) Could integration of local and global IO data provide useful insights to study presence/absence of unequal material exchange at sub-national level? A study of material flows at inter- and intra-national level demonstrated that a regional economy can play a twofold role, both as sink or source of raw materials and in value added, depending on its position in the global economic hierarchy
Tiivistelmä Tässä työssä tutkittiin innovatiivisia tapoja, joilla voitaisiin parantaa materiaalijalanjälki -tyyppisten indikaattoreiden käytettävyyttä panos-tuotos (Input-Output, IO) -analyysissa, kun niitä sovelletaan Materiaalivirta-analyysi (Material Flow Accounting, MFA) -metodiin. Seuraaviin tutkimuskysymyksiin haettiin vastauksia: 1) Mikä on sektorien yhdistämisen potentiaalinen vaikutus raaka-ainevirtojen IO-mallintamisessa ja miten poikkeamia voidaan estää? Tämän puitteissa tarkasteltiin mallinnusvirheitä, jotka johtuvat erilaisten toimialojen yhdistämisistä yhdeksi sektoriksi. 2) Voivatko alhaalta ylöspäin suuntautuvat lähestymistavat, kuten elinkaariarviointi parantaa tuotteisiin sisältyvien raaka-ainevirtojen arviointia? ja 3) Mitä vaikutuksia on laajan maantieteellisen kattavuuden IO-malleihin sisältyvien maakohtaisten tietojen yhdistämisestä LCA-pohjaisiin lähestymistapoihin, kun tavoitteena on laskea tuotteisiin sisältyviä raaka-ainemääriä? Tämän tutkimista varten kehitettiin lähestymistapa, joka yhdisti maakohtaiset tuotantosuunnitelmat ja elinkaariarvioinnin. Tämä lähestymistapa osoittautui hyödylliseksi tarkentamalla arvioita tuotteissa olevista raaka-aineista, vaikkakin sen soveltaminen edellyttää varovaisuutta, koska uusia vääristymiä voi syntyä. 4) Voidaanko uusia näkökulmia löytää uudella arvonlisäykseen perustuvalla allokointimenetelmällä, joka jakaa raaka-aineen louhinnan kullekin toimintaketjun osallistuvalle taloudelliselle toimijalle lisäarvon tuotannon mukaan? Tämän uuden kirjanpitomenetelmän mukaan jotkut maat ja alat ovat materiaali-intensiivisempiä kuin niitä on pidetty kulutuksen jalanjälkiallokointimenetelmien perusteella. 5) Onko korkean tulotason talouksien ja keskitasoiselle ja alhaiselle tulotasolle asettuvien maiden välillä epätasaisia vaihtoja, kun raaka-ainekulutusta ja arvonlisäystä mitataan? ja 6) Voisiko paikallisten ja globaalien IO-tietojen integrointi antaa hyödyllisiä näkökulmia tutkimukseen, joka tarkastelee epätasaisen aineenvaihdon esiintymistä tai puuttumista alueellisella tasolla? Materiaalivirtojen tutkiminen kansainvälisellä ja kansallisella tasolla, jossa yhdistettiin IO-tietokannat erilaisella maantieteellisellä resoluutiolla osoitti, että alueellisella taloudella voi olla kaksoisrooli sekä raaka-aineiden että arvonlisäyksen lähteenä tai nieluna riippuen sen asemasta globaalissa taloushierarkiassa

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Lutter, Franz Stephan, Stefan Giljum, and Martin Bruckner. "A review and comparative assessment of existing approaches to calculate material footprints." Elsevier, 2016. http://dx.doi.org/10.1016/j.ecolecon.2016.03.012.

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Effective implementation of resource policies requires consistent and robust indicators. An increasing number of national and international strategies focussing on resource efficiency as a means for reaching a green economy call for such indicators. As supply chains of goods and services are increasingly organised on the global level, comprehensive indica-tors taking into account upstream material flows associated with internationally traded products need to be compiled. Particularly in the last few years, the development of con-sumption-based indicators of material use also termed material footprints has made considerable progress. This paper presents a comprehensive review of existing methodol-ogies to calculate material footprint-type indicators. The three prevailing approaches, i.e. environmentally extended input-output analysis (EE-IOA), coefficient approaches based on process analysis data, and hybrid approaches combing elements of EE-IOA and process analysis are presented, existing models using the different approaches discussed, and advantages and disadvantages of each approach identified. We argue that there is still a strong need for improvement of the specific approaches as well as comparability of re-sults, in order to reduce uncertainties. The paper concludes with recommendations for further development covering methodological, data and institutional aspects.

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Чайка, Тетяна Юріївна. "Матеріальні потоки в готельно-ресторанному бізнесі: логістичний підхід". Thesis, Національний технічний університет "Харківський політехнічний інститут", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/39241.

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Матеріальні потоки є одним з об'єктів логістики готельно-ресторанного бізнесу. Матеріальний потік виникає в результаті переміщення матеріальних об'єктів у просторі. Таким чином, невід'ємними характеристиками матеріального потоку є: 1) рух; 2) матеріальна форма об'єкта. Поняття матеріального потоку доцільно поширити не тільки на продукцію (на всіх стадіях формування товару), а взагалі на все оборотні і необоротні активи, які є придатними до транспортування. Матеріальний потік в готельно-ресторанному бізнесі – це матеріальні ресурси, які знаходяться в русі (сировина, матеріали, незавершене виробництво, напівфабрикати, готова продукція, малоцінні і швидкозношувані предмети, основні засоби та ін.), та безпосередньо пов'язані з виробничим процесом підприємства готельно-ресторанної сфери. В якості основних відносних показників (характеристик) матеріального потоку вважаємо за доцільне виділити: 1) швидкість; 2) щільність; 3) інтенсивність; 4) потужність. Список додаткових характеристик матеріальних потоків надзвичайно різноманітний і при необхідності може бути підданий ієрархічної деталізації. Так, наприклад, можна виділити: номенклатуру та асортимент; фізико-хімічні властивості; характеристики тари (упаковки); умови договорів, відповідно до яких відбувається переміщення матеріальних ресурсів та інші характеристики.

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André, Axel. "Raw Material Consumption - Ett mått på Sveriges materialanvändning i ett mer resurseffektivt samhälle." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-367195.

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Att kunna mäta vår materialanvändning är centralt i omställningen till ett resurseffektivare samhälle och en cirkulär ekonomi. Inom EU används Domestic Material Consumption (DMC) som indikator för materialanvändning. Den beräknas genom att addera de material som ett land utvinner, plus de material som importeras, minus de material som exporteras. Det finns kritik mot DMC då den endast tar hänsyn till vikten på import- och exportprodukter då de korsar landsgränsen. DMC inkluderar inte de uppströms material som gått åt för att producera en produkt, men som inte syns i slutprodukten (den så kallade materialryggsäcken). Den ökade globaliseringen har för många länder lett till en förflyttning av produktion utomlands, och för att beräkna dessa länders totala materialanvändning krävs det att hänsyn tas till importerade och exporterade produkters materialryggsäck. Raw Material Consumption (RMC) är en indikator som tar hänsyn till materialryggsäcken, men den har idag ingen standardiserad beräkningsmetod. Både RMC och DMC används inom Agenda 2030 för att följa upp FN:s hållbarhetsmål 12 ”Hållbar konsumtion och produktion”, samt hållbarhetsmål 8 ”Anständiga arbetsvillkor och ekonomisk tillväxt”. Endast DMC används idag inom EU. Syftet med projektet var att beräkna Sveriges materialanvändning med hjälp av indikatorn Raw Material Consumption (RMC), samt att identifiera styrkor och svagheter hos RMC. Eurostats RME-verktyg användes för att beräkna RMC. Enligt RMC ökade Sveriges totala materialanvändning från 198 miljoner ton råmaterialekvivalenter (RME) år 2008, till 221 miljoner ton RME år 2015, motsvarande 21,4 ton RME per capita 2008 till 22,6 ton RME per capita 2015. Resultaten jämfördes med resultat för Sveriges DMC som Statistiska Centralbyrån tagit fram. RMC och DMC gav liknande resultat för Sveriges totala materialanvändning. Detta tros bero på att materialryggsäcken för den svenska importen är ungefär lika stor som för exporten och att den största materialkategorin, icke-metalliska mineraler, utgör en liten del av vår handelsbalans och därför inte påverkas i någon större utsträckning när importerade och exporterade produkters materialryggsäck inkluderas. På materialkategorinivå är dock skillnaderna mellan RMC och DMC större. Resultat från Eurostats RME-verktyg som tagits fram i denna studie, har jämförts med resultat som OECD och UNEP tagit fram för Sveriges RMC. De har använt en annan beräkningsmetod än den RME-verktyget tillämpar. Skillnaden i total RMC för de olika beräkningsmetoderna är mellan 11 % och 22 %. På materialkategorinivå är skillnaderna större, över 50 % för fossila bränslen exempelvis. Liknande resultat har påvisats i en studie som jämförde Österrikes RMC för år 2007 med olika beräkningsmetoder. Både DMC och RMC kan användas som indikatorer för resurseffektivitet och cirkulär ekonomi, men vid jämförelse mellan länder är RMC teoretiskt en mer lämplig indikator. Detta eftersom många länder idag har flyttat stora delar av sin produktion utomlands, och DMC därför riskerar att ge en skev bild över resurseffektivitet och frikoppling, när materialryggsäcken inte inkluderas.
Being able to measure the amount of materials used in society, is central in the transition to a resource-efficient and circular economy. Within the EU, Domestic Material Consumption (DMC) is currently used as indicator for material use. It is calculated by adding the materials that a country extracts, plus the materials imported, minus the materials being exported. There is criticism of DMC, as a measure, since it only considers the weight of imported and exported goods when they cross the country border. It does not consider the upstream materials needed to produce a product, which are not represented in the final product (the so-called material backpack). Globalisation has led to a geographical disconnection in production and consumption, and to consider net-importing countries’ total material consumption, it is necessary to include traded product’s material backpack. Raw Material Consumption (RMC) considers the material backpack, but is currently without a standardised calculation method. Both RMC and DMC are used in Agenda 2030 to follow up the UN Sustainability Development Goal 12 "Sustainable Consumption and Production", as well as Goal 8 "Decent Work Conditions and Economic Growth". Only DMC is used today in the EU. The aim of this project was to calculate Sweden’s material consumption, using the indicator Raw Material Consumption (RMC), as well as identifying strengths and weaknesses of RMC. For calculating RMC, Eurostat’s RME-tool has been used. According to RMC, Sweden's total material usage increased from 2008 when it amounted to 198 million tonnes of raw material equivalents (RME), to 221 million tonnes RME in 2015. There has also been an increase per capita: 21,4 RME per capita in 2008 to 22,6 RME per capita in 2015. These results have been compared with the results for Sweden's DMC, calculated by SCB. RMC and DMC gave similar results for Sweden's total material consumption. This is believed to be due to the similar size of the material backpack of imports and exports. Another reason is believed to be due to Sweden’s largest material category, non-metallic minerals, is a small part of our trade balance, and therefore is not affected when the material backpack is included. At the material category level, however, the differences between RMC and DMC are greater. Results from Eurostat's RME tool, calculated in this study, have been compared with results presented by the OECD and UNEP. They have used a different calculation method for Sweden’s RMC than the RME tool applies. The difference in total RMC for different calculation methods is between 11 % and 22 %. At material category level, the differences are greater, more than 50 % for fossil fuels, for example. Similar results have been presented in a study over Austria's RMC for the year 2007, using different calculation methods. Both DMC and RMC can be used as policy-support for resource efficiency, but RMC is theoretically a more suitable indicator for comparison of countries. This is since many countries today have moved a significant share of their production abroad, and DMC therefore risks displaying a false perception of resource efficiency and decoupling, when the material backpack is not included.

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Stridh, Madeleine. "Material flow : An analysis of a production area for improved material flow." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-80193.

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Focus in the world today is quality and customer orientation. An organization needs to understand the concept of value from the perspective of a customer in order to keep up with expectations on quality, and the turbulent and global environment of today characterized by rapidly changing conditions. This master thesis project was conducted at ABB in Sweden during spring 2020. It is essential for ABB to have an ongoing focus on improvement to maintain a successful organization and enable a competitive future of quality and innovation. The aim of this project was to identify ways to improve material flow and reduce the amount of non-value-added activities that exist in a particular assembly process today. The objective of the project was to conduct proposals on realistic actions for improvement for implementation. Initially in the project a current state was performed and compiled into a specification of requirements and visualized through overall mapping of the material and communication flow. Two of the requirements were reducing the total lead time and ensure the same, or improved, physical and psychosocial work environment. The result of the current state showed that material is not available when needed, material shelves are not structured, and material flow is not optimal. Analysis methods used for analyzing the current state were material flow charts, value stream mapping and spaghetti diagrams. The outcome of the performed analyzes were then used as the foundation for a compiled list of problem areas. All previous performed work was then summarized, discussed and developed into a list of actions for improvement. This phase was performed by initially generating a great amount of ideas, which were then reviewed and evaluated in consideration of the specification of requirements. In addition to the final list of actions, a mapping of the future state was conducted to support the actions and visualize what a future state could look like if the actions are implemented. Lastly, the final list of actions was complemented with another list – a living document of the actions. This document gives the opportunity on a regular basis to monitor progress and should be regularly reviewed and updated. To ensure a successful implementation of improvement work based on the conducted action list, it is recommended to define and clarify responsibility for each action as well as target date and end date. Furthermore, the list should be continuously modified to ensure implementation. It is as well recommended to acknowledge implemented improvements in parallel with performing actions to maintain motivation. Additionally, participation in implementation and promoting dialogue, transparency and respect are valuable factors reducing the negative effects of the implementation of improvement concepts and contributes to a sustainable development of the improvement work.

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Helber, Stefan. "Performance analysis of flow lines with non-linear flow of material /." Berlin : Springer, 1999. http://opac.nebis.ch/cgi-bin/showAbstract.pl?u20=3540659544.

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Fan, Xiaolin. "Material flow in a wood-chip refiner." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63977.

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Mullen, T. D. "Material flow control in complex manufacturing systems." Thesis, University of Strathclyde, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360792.

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Liechty, Brian C. "Material Flow Behavior in Friction Stir Welding." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2403.pdf.

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Larsson, Simon. "Modelling and Characterisation of Granular Material Flow." Licentiate thesis, Luleå tekniska universitet, Material- och solidmekanik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-62670.

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Granular materials are very common both in nature and in industry, and their extensive use means that there are financial incentives for increased efficiency. There are huge costs related to their use and handling, which is a major motivation for increased knowledge of the behaviour of granular materials at different loading conditions. The development of tools for numerical simulation of granular materials at diverse flow conditions gives the opportunity to study and optimise various industrial processes. In order for such tools to be trustworthy, calibration and validation against experimental results is essential. Thus, experimental methods for accurate measurement and characterisation of granular material flow are required. The objective of this thesis is to contribute to the knowledge of experimental characterisation and numerical modelling of non-cohesive, dry granular materials, at dissimilar flow conditions. In order to fulfil this objective, an experimental method, able to capture the flow behaviour of granular materials is developed. The method is based on the digital image correlation technique, and it is used for field measurements of displacement and velocity. The devised method is used to obtain field measurements for the flow of sand, tungsten carbide powder and potassium chloride. For modelling and simulation, the smoothed particle hydrodynamics (SPH) method, and a pressure-dependent, elastic-plastic constitutive model are used. In this thesis, experimental characterisation and numerical modelling of granular material flow is performed in a number of applications. An experimental powder filling rig is used to study the flow during filling of sand into a die. A high-speed digital camera is used to record the flow, and the digital image correlation technique is used to obtain field measurements during the filling. This method is also applied in another experimental setup, where flow during filling of spherical tungsten carbide powder into a die is studied. The filling of tungsten carbide powder is simulated using the SPH method, and the results are compared to the field measurements with good agreement. Furthermore, the flow of potassium chloride is studied experimentally in the collapse of a granular column and in the discharge from a flat bottomed silo. The material flow process in both the column collapse and silo discharge are simulated using the SPH method. The results from simulations are found to be in agreement with observations reported in literature, and with experimental measurements obtained in this work. In conclusion, an experimental method for characterising granular material flow through field measurements is presented. The method is used to support the exploration of numerical tools for modelling and simulation of granular material flow. Furthermore, the high accuracy field measurements are used for improved calibration and validation of numerical methods. Reliable numerical simulations allows for study of the mechanisms that are present during granular material flow, mechanisms that might be hard or even impossible to investigate experimentally. The work within the present thesis contributes to the knowledge of both experimental characterisation and numerical modelling of granular material flow.

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Fu, Xinkai. "Assessing byproduct mining and metal recycling as indicators of material criticality." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/123618.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2019
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 170-184).
The development of advanced technologies relies on using a broader suite of elements from the periodic table, and many agree that the future availability of a set of 'critical materials' is an issue of global concern. However, assessments of material criticality are often overly general, leading to excessive concerns by policy makers and market participants. A quantitative and detailed investigation for supply risk indicators is necessary to further understand the risk associated with specific materials. This thesis investigates two aspects related to material criticality: 1) the status of a metal being produced as a byproduct; 2) The market impact of increased metal recycling. To identify the type of major risks associated with a byproduct metal, a techno-economic analysis is performed on 42 carrier-byproduct metal pairs, by employing cluster analysis and econometric modelling.
Contrary to conventional view, it is found in several case studies that the availability of a byproduct metal is not directly limited by carrier supply, but rather limited by the lack of incentive to improve recovery efficiencies. Therefore, developing alternative extraction processes with high recovery rate is proposed as a mitigation strategy for byproduct metals. The economic feasibility of such processes is examined, first in a screening assessment and then in a detailed case study for extracting indium as byproduct of zinc. It is demonstrated that an alternative process could significantly increase byproduct supply, by up to 10% in the case of indium. A bottom-up copper market simulation system is developed by modeling the behaviors of market participants, to estimate the market impact of increased metal recycling. Results from the simulation demonstrates the existence of various rebound effects for primary copper production.
Depending on the size and duration of secondary supply shocks, these rebound effects can offset 50% to 90% of the environmental benefits of recycling. In terms of carrier recycling impacting byproduct supply, it is shown that recycling as carrier metal supply risk mitigation strategy would not significantly hurt the availability of byproduct metal.
by Xinkai Fu.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Materials Science and Engineering

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14

Mundy, Michael. "Unbound pavement materials and analytical design." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396129.

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15

Kopec, Grant Michael. "Examining natural resource futures with material flow analysis." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709409.

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16

Hoffman, Kinsey H. "Ecohydrologic Indicators of Low-flow Habitat Availability in Eleven Virginia Rivers." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/56978.

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Increasing demand and competition for freshwater is threatening instream uses including ecosystem services and aquatic habitat. A standard method of evaluating impacts of alternative water management scenarios on instream habitat is Instream Flow Incremental Methodology (IFIM). The primary outputs of IFIM studies are: 1) habitat rating curves that relate habitat availability to streamflow for every species, lifestage, or recreational use modelled; and 2) habitat time series under alternative water management scenarios. We compiled 428 habitat rating curves from previous IFIM studies across 11 rivers in Virginia and tested the ability to reduce this number based on similarities in flow preferences and responses to flow alteration. Individual site-species combinations were reduced from 428 objects to four groups with similar seasonal habitat availability patterns using a hierarchical, agglomerative cluster analysis. A seasonal habitat availability (SHA) ratio was proposed as a future indicator of seasonal flow preferences. Four parameters calculated from the magnitude and shape of habitat rating curves were proposed as response metrics that indicate how a lifestage responds to flow alteration. Univariate and multivariate analyses of variance and post-hoc tests identified significantly different means for the SHA ratio, QP (F=63.2, p<2e-16) and SK (F=65.6, p<2e-16). A reduced number of instream flow users can simplify the incorporation of aquatic habitat assessment in statewide water resources management.
Master of Science

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17

Campbell, Bruce A., Gareth A. Morgan, Jennifer L. Whitten, Lynn M. Carter, Lori S. Glaze, and Donald B. Campbell. "Pyroclastic flow deposits on Venus as indicators of renewed magmatic activity." AMER GEOPHYSICAL UNION, 2017. http://hdl.handle.net/10150/625517.

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Radar bright deposits on Venus that have diffuse margins suggest eruptions that distribute debris over large areas due to ground-hugging flows from plume collapse. We examine deposits in eastern Eistla, western Eistla, Phoebe, and Dione Regiones using Magellan data and Earth-based radar maps. The radar bright units have no marginal lobes or other features consistent with viscous flow. Their morphology, radar echo strength, polarization properties, and microwave emissivity are consistent with mantling deposits composed of few centimeters or larger clasts. This debris traveled downhill up to similar to 100km on modest slopes and blanketed lava flows and tectonic features to depths of tens of centimeters to a few meters over areas up to 40x10(3)km(2). There is evidence for ongoing removal and exhumation of previously buried terrain. A newly identified occurrence is associated with a ridge belt south of Ushas Mons. We also note radar bright streaks of coarse material west of Rona Chasma that reflect the last traces of a deposit mobilized by winds from the formation of Mirabeau crater. If the radar bright units originate by the collapse of eruption columns, with coarse fragmental material entrained and fluidized by hot gases, then their extent suggests large erupted volatile (CO2 or H2O) amounts. We propose that these deposits reflect the early stage of renewed magmatic activity, with volatile-rich, disrupted magma escaping through vents in fractured regions of the upper crust. Rapidly eroding under Venus surface conditions or buried by subsequent eruptions, these markers of recently renewed activity have disappeared from older regions.

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18

Gustafsson, Daniel, and Mikael Johansson. "A Material Flow Evaluation at Scania Production Slupsk S.P.S." Thesis, Linköping University, Department of Management and Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10133.

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This master’s thesis is performed at Department of Management and Engineering Linköping University, for Scania Omni at Scania Production Slupsk (S.P.S). Omni is responsible for development, manufacturing and marketing of city, suburban and intercity buses. After acquisition of the production unit in Slupsk in 2002 lower production cost per bus is possible. But without control over the organisation costs are rising due to late delivery fees and high stock levels. At the outset, the thesis included three clearly defined objectives:

- Map the present situation at Scania Production Slupsk regarding material flow from supplier to assembly line including a part and storage analysis.

- Benchmark the current routines at Scania Production Slupsk with other successful companies. Furthermore, conduct literature research in order to find theories and philosophies that support problem analysis and thesis solution.

- Develop standard routines for material control methods (MCM) and material supply methods (MSM).

A complimentary objective is to work as a catalyst during the time of the thesis.

The mapping of the present situation showed that MCM and MSM are very tight connected to each other. It was questioned whether this structure was the best way to manage the material flow. After a parts and storage analysis, material was divided into different segments depending of price, consumption and movement.

The benchmarking studies showed different ways to manage the material flow. Implementation of unit load, kanban and clear defined interface between departments showed potential to improve the material handling and increase effectiveness.

New routines and part segment definitions described in a logistics manual (Appendix I) were made align with a comparison between previous and recommended definitions.

The result showed that some parts needs to be controlled differently. Primary recommendations are that logistics manual shall be used when new parts are introduced into the Scala system. Responsible personnel are suppose to give suggestion concerning decision making of MCM and MSM and with help of the logistics manual the work can be more efficient, resulting in a material flow that is flexible and have potential for improvements.

Secondary, to avoid material handling to some extent implementation of two-bin system is recommended. Additional recommendations regarding two-bin system is to handle material according to unit load, which enable FIFO, traceability and higher turn over rate

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19

Asef-Vaziri, Ardavan. "A loop material flow system design for manufacturing plants." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27871.pdf.

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20

Shchekutin, Nikita [Verfasser]. "Layout Optimization for Cognitive Material Flow Systems / Nikita Shchekutin." Garbsen : TEWISS - Technik und Wissen GmbH, 2019. http://d-nb.info/1196044139/34.

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21

Haidemenopoulos, Gregory N. "Heat flow and material degradation during laser metal forming." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/14898.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering and Dept. of Materials Science and Engineering, 1985.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaves 144-146.
by Gregory N. Haidemenopoulos.
M.S.

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22

Low, Man-Shi. "Material flow analysis of concrete in the United States." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33030.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.
MIT Rotch Library copy is in leaves.
Also issued in leaves.
Includes bibliographical references (p. 155-164).
Concrete is the second most consumed material in the world after water. Due to the sheer mass of concrete consumed annually and its associated resource and environmental impacts, improving the materials management of concrete consumption is a critical problem in the United States. It is increasingly evident that the society lacks knowledge of the collective material composition of the urban environment-of how we produce, consume and dispose of concrete. This thesis argues that the lack of informational linkages is driving the individual approaches of the construction industry, policy makers, environmental agencies and waste management industry, which results in the current segregated and government-subsidized material management. In order to identify opportunities for more effective materials management, this thesis performs the first comprehensive Material Flow Analysis for concrete in the United States for the year of 1996 to identify opportunities for more effective materials management. The dominant concrete products and the end-use categories in the United States are identified. The associated water, energy and fuel consumption and emissions produced are also incorporated. Five lifecycle stages are covered: (i) extraction of raw materials, (ii) cement manufacturing, (iii) production, (iv) use and (v) waste management of concrete. Two untapped material management opportunities are identified: minimizing water consumption during the extraction stage and the off-site production stage.
(cont.) In addition, three key observations are made: (i) the energy efficiency of the cement industry in the United States is close to saturation, (ii) product choice and concrete design are dominant factors for a more responsible materials consumption approach, and (iii) demand-side management is recommended as a more optimal approach than recycling in dealing with the current construction trends in the United States.
by Man-Shi Low.
S.M.

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23

Mwansa, Sonny. "Segregation and material flow along low aspect SAG mills." Master's thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/5497.

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Includes bibliographical references.
The significance of this study is primarily intended to provide better understanding of axial segregation and flow of particles along SAG mills. Additionally, the current SAG mill models developed using "short" Australian and North American style mills exposes inaccuracies when applied to predict the performance of "long" mills. Thus the results of this study are expected to be useful for improving modelling of long SAG mills. Several studies of radial and axial segregation in tumbling horizontal devices at laboratory-scale and a few on pilot-scale have been conducted in the past by various researchers. Recently, industrial-scale studies of axial segregation in kilns and dry milling, particularly in the cement industry have also been conducted. However, there seems to be no work reported and cited in the literature on axial segregation studies along SAG mills. Thus the lack of previous segregation research along SAG mills has exposed a knowledge gap in the subject.

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24

Abdali, Saleh S. "Numerical simulation of viscoplastic material flow through extrusion dies." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7824.

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Various flows through extrusion dies have been studied for viscoplastic materials exhibiting a yield stress (Bingham fluids). These include entry flows from a reservoir into a die and exit flows from a die into the atmosphere under the influence of a pressure gradient. The materials are modelled by a constitutive equation of Bingham fluids with yield stress, as modified by Papanastasiou to include an exponential term for low strain rates and to avoid discontinuities. This equation applies everywhere in the flow field in both yielded and practically unyielded regions. The Finite Element method is used to discretize the domain and solve the set of conservation and constitutive equations along with the proper boundary conditions. The results are given as a function of a dimensionless Bingham number (Bi) or yield stress ($\tau\sbsp{y}{*}$). The emphasis is on determining the extent and shape of unyielded/yielded regions as well as the extrudate swell for planar and axisymmetric geometries. It is found that reduction in swelling occurs as the amount of yield increases, which becomes contraction and then it asymptotically increases to reach 1 as Bi $\to \infty$. The results for the pressure necessary to push the material through are used to determine the excess pressure losses over and above the Newtonian values, giving rise to entrance, exit and the total end correction. These are found to be substantially higher than the Newtonian values as Bi increases, reaching values close to 4 times their Newtonian counterparts. The results correctly capture the location and extent of solid and fluid regions in such flows, which is of considerable interest for industrial purposes. The combined effect of entry and exit flow under non-isothermal conditions has been also studied in an effort to simulate a visco-elastico-plastic material for which experimental data are available in the literature. (Abstract shortened by UMI.)

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Baudet, Alvaro. "Optimize cold sector material flow of a steel rolling mill." Thesis, KTH, Industriell produktion, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-50380.

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The steel production is a highly capital and energy intensive industry that due to recent raw materials’ price increase and lowered demand, it has been squeezed and forced to look more deeply on how to add value to the customer at lower operative costs. The project was carried out on site at the ArcelorMittal’s millin Esch-Belval, Luxembourg which comprises an integrated melt shop, continuous casting plant and the rolling mill with the objectives of proposing optimization rules for the cold sector of the rolling mill and to analyze the impact of the future truckbay shipment area. The course of action followed was to draw a Value Stream Map (VSM) in order to understand the plants’ current status and serve as a roadmap to build a discrete event simulation model that after its validation, served as a support tool to analyze what-if scenarios. Similarly, a current status analysis of the shipment/stock area was conducted collecting statistics about potential truckshipments and finally proposing a series of recommendations for its operation. The main proposed solutions to optimize the rolling mill’s cold sector were:(a) Integer programming model to globally optimize the scrap level when cutting the mother beams to customer size beams. (b) Updating pacemaker parameters and (c) Local process time improvements. Concerning the future truck loading, the simulation model was used as a support tool to dimension the transition area between the cranes’ and forklift operations resulting in a 6-9 bundles buffer capacity. Additionally, the current length-based storage policy was found to have competitive objectives so a turnover class-based storage policy is proposed with A, B, C classes which should provide an improved organization of the stock and travel distance of the cranes. The evaluation of the cranes’ performance remains an issue since there are currently no objective measures like, for instance, travelled distance. Optical measuring devices are suggested as one option to have a performance indicator that would help further investigate root cause problems in the shipping/stock area.

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Liu, Fuh-hwa Franklin. "Analytical approaches for designing a class of material flow systems." Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/24254.

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27

Schleyer, Marc. "Discrete time analysis of batch processes in material flow systems." Karlsruhe : Univ.-Verl. Karlsruhe, 2007. http://www.uvka.de/univerlag/volltexte/2007/243/.

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28

Leese, Hannah. "Electroosmosis in nanoporous membranes : connecting material properties to flow behaviour." Thesis, University of Bath, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601631.

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The development of nanoporous materials has received considerable attention in nanofluidic studies in recent years. Furthering earlier research, the present thesis offers a systematic study of two nanoporous materials-nanoporous alumina membranes and carbon nanotube membranes-with a view to establishing their electroosmotic and fluid-flow behaviour at the nanoscale. The nanoporous alumina membranes were studied for their own electroosmotic and fluid-flow properties, and utilised as templates for the production of the carbon nanotube membranes also investigated in this study. The advanced control provided by the fabrication processes of both materials allowed for systematic investigations into the effects of pore diameter and surface chemistry on both electroosmotic and pressure-driven flows. Nanoporous alumina membranes were developed with pore diameters of< 10 nm. The effect of nanostructure and surface chemistry on macro wetting properties was analysed in detail. Flow enhancements were observed in hydrophilic alumina nanochannels with inner diameters of 40 to 25 nrm. Atomic force microscopy force measurements provided further insight into fluid-solid interactions at the nanoscale. A systematic investigation of nanoporous alumina DC electroosmotic pumps with pore diameters down to 8 run was also undertaken with sodium tetraborate buffer operated at Δ V = 10 V. Concentration polarization was identified as the principal challenge to sustained electroosmotic flow. By optimising the electroosmotic process, particularly the rig design and buffer concentration, an EO pump was developed with a lifetime of up to 4 hours. Carbon nanotube membranes with a range of pore diameters were also investigated for their electroosmotic and pressure-driven flow properties. The synthesis of carbon nanotubes was optimised to obtain unblocked and functioning membranes. Flow enhancements were observed in engineered carbon nanotube membranes with pore diameters down to 16 run. Electroosmotic flow rates in carbon nanotube membranes were similar to those of nanoporous alumina. Two electrolytes-sodium tetraborate and sodium chloride-were investigated in electroosmotic flow experiments with carbon nanotube membranes. This allowed for further investigation of electroosmosis and electric double layer overlap.

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29

Kim, Tongbeum. "Fluid-flow and heat-transfer in a lattice-frame material." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616470.

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30

Milne, Fraser Dalton. "Topographic and material controls on the Scottish debris flow geohazard." Thesis, University of Dundee, 2008. https://discovery.dundee.ac.uk/en/studentTheses/eb4a6b03-8024-4818-8e92-ce1fd3c77209.

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Debris flows can be considered the most significant geological hazard in areas of high relief in Scotland having impacted upon slope foot infrastructure several times in recent years. The potency of this geohazard is anticipated to increase over the coming decades due to a climatologically enforced upturn in debris flow frequency. In thisresearch material and topographic controls on debris flow activity are investigated using a combination of field and laboratory based analysis of debris flows at six study sites across upland Scotland. Centrifuge modelling is also used to simulate theinitiation of debris flows in soils with varying particle size distributions.Spatial densities of debris flow measured in the field indicate that hillslopes underlain by sandstone and granitic bedrocks, which tend to be mantled by coarser sand rich soils, have a greater frequency of flows than those underlain by schist andextrusive lava bedrocks. Higher debris flow densities on slopes underlain by sandstone and granite lithologies are facilitated by high permeability in overlying regolith matrixes allowing more rapid increase in pore water pressures duringrainstorms although this is likely to be further influenced by packing and organic content. Centrifuge modelling of hillslope debris flows also demonstrate that sandier soils are generally geotechnically more susceptible to slope failure.The susceptibility of a hillslope to debris flow is strongly influenced by slope geometry and morphology. Hillslopes with persistently steep slopes and a high incidence of concavities, gullies and couloirs are topographically more predisposed todebris flow activity due to greater shear stresses and morphologically controlled, gravity induced concentrations of hillslope hydrology. The majority of material in channelised debris flows is entrained during the gully propagation stage of the massmovement. Consequently, such events can be considered accumulative channelised debris flows. Longer and steeper gullies with greater sediment capacities are more likely to yield larger flow mass movements. Coupling between open hillslopes andbedrock gullies is shown to be an essential component for conceptualisation of the debris flow geohazard.Due to the role they play in amplifying debris flow magnitude, hazard management should be focussed around bedrock gullies and stream channels. Highesthazard rankings should be assigned to slope foot infrastructure in proximity to gullied stream channels with high sediment capacities and long, steep profiles conducive to large accumulative channelised debris flows. To avoid detrimental aesthetic impact, hazard management should be strongly geared towards utilisation of lower impactexposure reduction techniques and less visually intrusive engineering approaches such as increasing culvert capacity to accommodate debris flows. During realignment or the planning of future transport infrastructure, culverts with capacities significantly exceeding those required for purely hydrodynamic considerations should be placed straight on to stream channels avoiding proximal gully bends.

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Kim, Junil. "Computer modelling and analysis of anisotropic material flow in compression molding of short-fiber-reinforced composite material /." The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu148768114854067.

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32

Ozen, Aykut. "Material Flow Cost Versus Congestion In Dynamic Distributed Facility Layout Problem." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609602/index.pdf.

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In this thesis, we study both dynamic and distributed facility layout problems, where the demand for product mix changes over time. We propose a new simulated annealing algorithm, SALAB, for the dynamic facility layout problem. Four variants of SALAB find the best known solution for 20 of the 48 benchmark problems from the literature, improving upon the best known solutions of 18 problems. We modify SALAB to obtain DSALAB, solving the dynamic distributed facility layout problem with the objective of minimizing relocation cost and total (full and empty) travel cost of the material handling system. We simulate DSALAB solutions of randomly generated problems to study the tradeoff between total cost and congestion in the system. Our experimental results indicate that distributing the department duplicates throughout the facility reduces the total cost with diminishing returns and causes increasing congestion. Therefore, distribution beyond a certain level is not justified.

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33

J, Nagoor Kani. "Regularization of the Material Discontinuities in the Two Phase Flow Simulatin." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-132186.

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Proper understanding of flow involving more than one phase is essential in understanding many physical phenomena. One such is the crystal growth where the convection on the surface produces an increase in the uncontrollable number of dislocations leading to defects. Geometry and physical condition of the inter-facial layer separating the two phases is crucial in controlling such physical evolution. On the microscopic scale, the inter-facial layer is of microscopic width such that there is a continuous transition of fluid properties like density from one phase to the other. More over the molecules on the inter-facial layer are unevenly pulled by the surrounding molecules resulting in the inter-facial tension. On the macroscopic scale, the continuous approximation of fluids replaces the inter-facial layer of microscopic width by a sharp mathematical interface across which there is a jump discontinuous change from density 1 to density 2. Since the motion of multi phase flow is governed by the Navier-Stokes equations by which the fluid properties like density and viscosity and the dependent variables like velocity and pressure should be smooth, fluid properties are generally smeared out properly. In such formulation, inter-facial tension effects in the equations are introduced by framing force terms. One such method of properly capturing interfacial effects on the fluid motion is the conservative level set method. But the formulation made by the conservative level set method on the fluid properties and on the force term becomes bad on modeling the physical system involving motion due to the inter-facial tension gradient. Aim of this thesis is to emphasize the importance of formulation to smoothen the jump discontinuity of fluid properties across the interface and framing the force term correctly to capture the inter-facial tension effects in the fluid motion. Here the simple physical system involving marangoni convection is taken as a model. Then it is solved with jump conditions across the interface. The fluid properties and the force term when smoothened by the conservative level set function results in the solution deviating from the physical model. So the fluid properties and the force term are reformulated to get an approximate solution matching the exact solution.

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34

Besic, Dino. "Improving facility layout & logistics to increase the material flow efficiency." Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26531.

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When the internal logistics of a company is in a well working condition, the manufacturing process is more efficient and a more efficient material handling process can be developed. A company with the interest of decreasing internal material handling is Scapa Bedding AB, a middle size bed manufacturer situated in Rydaholm, Sweden. Today, Scapa Bedding AB is facing a problem since there is no documentation regarding the material handling, no maps have been developed that displays the internal transports. This thesis attends the question of how to decrease the material handling within the production areas. To construct a solution for the material handling problem tools such as PDCA and DMAIC were used as a foundation in the development of a model that would be applicable on a company of this size. The purpose of the work is to locate and identify the wasteful activities regarding the material handling, and to streamline the activities to reach a minimum of material handling. By extracting data from observations, discussions and interviews the thesis will provide the reader with a problem background and a constructed model the tackle the problem. The model will provide support to locate inefficiencies within the company and in a later stage to develop improvement alternatives relevant to the case. The chosen improvement alternative will in a cost effective way be a solution to the problem.
När den interna logistiken på ett företag är i ett välfungerande tillstånd kan en mer effektiv produktion och materialhanteringsprocess utvecklas. Ett företag som arbetar för att minska på den interna materialhanteringen är Scapa Bedding AB, en medelstor sängtillverkare belägen i Rydaholm, Sverige. Idag står Scapa Bedding inför ett problem då det saknas dokumentation och rutiner på dess befintliga materialhantering. Detta arbete kommer att hantera frågan om hur materialhanteringen inom produktionsarean kan reduceras. För att utveckla en lösning på materialhanteringsproblemen har verktyg som PDCA och DMAIC använts som en grund i utvecklandet av en modell som kan tillämpas på ett medelstort producerande företag. Syftet med detta arbete är att lokalisera och identifiera aktiviteter som bidrar med slöseri inom materialhanteringen samt att effektivisera dessa aktiviteter för att reducera den totala materialhanteringen. Genom att hämta data från observationer, diskussioner och intervjuer kommer detta arbete att erbjuda läsaren en bakgrund på ett problem och en lösning i form av en modell för att lösa det aktuella problemet. Modellen kommer att erbjuda stöd i sökandet efter ineffektiviteter inom företaget för att i ett senare skede utveckla ett kostnadseffektivt förbättringsalternativ.

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35

Bakkalbasi, Omer. "Flow path network design and layout configuration for material delivery systems." Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/25617.

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36

Ozalp, Nesrin. "Energy, material and emissions flow models of the U.S. chemical industry /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/7123.

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37

Danius, Lena. "Data uncertinties in material flow analysis.Local case study and literature survey." Licentiate thesis, KTH, Chemical Engineering and Technology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1502.

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The aim of this thesis is to discuss and analyse the influenceof data uncertainties with regard to the reliability of materialflow analysis (MFA) studies. MFA, as a part of environmentalsystems analysis, is a method belonging to the research field ofindustrial ecology and more specifically industrial metabolism.As such, the method strives at giving a holistic view of thecomplex world we live in, in order to reduce negativeenvironmental impact. Among other things, MFA studies have beenproposed to be useful for priority setting and following up inmunicipalities.

Serving as a starting point is a local case study of flows ofnitrogen in a Swedish municipality, Västerås. The casestudy has been performed using the ComBoxmodel. The years studiedare 1995 and 1998. The main sectors in society emitting nitrogento water were identified as the agricultural and householdsectors. The dominating sectors emitting nitrogen to air wereidentified as the agricultural, transport and infrastructuresectors.

As a basis for discussing data uncertainties qualitatively andquantitatively a literature survey was performed. 50 articles andbooks were identified as in some way or another dealing with datauncertainties in MFA. The literature survey showed that theuncertainties for results from a MFA study might vary between±30 % and a factor 10 depending on what kind of parameter isinvestigated. Only one method was found that dealt with datauncertainties in MFA in a complete way; a model developed byHedbrant and Sörme (HS model).

When applying the HS model to the case study of nitrogen flowsin Västerås, it was found that when uncertaintyintervals were calculated the possible conclusions changed. Ofthe two pair of flows compared in relation to priority setting,none of the earlier conclusions remained. Of the three flowsanalysed in relation to following up, only the flow from onepoint source supported the same conclusion when uncertainty wasconsidered.

In all, it is concluded that data uncertainties in MFAanalysis are an important aspect and that further research isneeded in order to improve input data quality estimations andframeworks for determining, calculating and presenting data, datauncertainties and results from MFA studies. However, theunderlying reality remains, e.g. that management of materialflows are important for understanding and reducing the negativeenvironmental impact. Thus, MFA is one useful tool in thiswork.

Keywords:data uncertainties, sensitivity analysis,Material flow analysis, MFA, method to determine datauncertainties, case study, ComBox model, nitrogenflows.

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38

Sanders, Johnny Ray. "Understanding the material flow path of the friction stir weld process." Master's thesis, Mississippi State : Mississippi State University, 2005. http://library.msstate.edu/etd/show.asp?etd=etd-11102005-142957.

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39

Choi, Soodong. "Material flow system integration in EOQ, ELSP, and Kanban production environments /." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9901227.

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40

Polizzi, Michael A. (Michael Allen). "Methodology for the synchronization of material flow in an assembly plant." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/37803.

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Thesis (M.S.)--Massachusetts Institute of Technology, Sloan School of Management, 1996, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1996.
Includes bibliographical references (leaf 60).
by Michael A. Polizzi.
M.S.

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41

Wang, Li-Chih. "Time dependent models of material flow in small-lot assembly systems /." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487671108303843.

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42

Stellwag, Brigitte. "Factory Planning – The Creation and Evaluation of Material Flow- oriented Layouts." Thesis, KTH, Industriell produktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-218030.

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43

MODOLO, A. V. F. "ESCOAMENTO de Materiais Viscoplásticos: Dam Break Flow." Universidade Federal do Espírito Santo, 2017. http://repositorio.ufes.br/handle/10/9757.

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Made available in DSpace on 2018-08-02T00:02:59Z (GMT). No. of bitstreams: 1 tese_11317_ALAN VICTOR FERREIRA MODOLO .pdf: 4918358 bytes, checksum: 4f9210c521179af173132f3ad0f9737f (MD5) Previous issue date: 2017-03-24
Ao longo do último século, o Dam Break Flow vem sendo estudado por muitos autores. A compreensão deste tipo de fenômeno é de grande relevância, uma vez que envolve aplicações em barragens que oferecem múltiplos benefícios para a humanidade. Porém, o rompimento de uma dessas barragens pode trazer consequências indesejáveis e imensuráveis para a sociedade e para o setor de mineração, por exemplo. Neste trabalho estamos interessados em entender como o número de Froude e as propriedades não-newtonianas, particularmente a viscoplasticidade, afetam o perfil de interface do escoamento e a distância alcançada pelo material após o Dam Break Flow. Tais resultados são comparados com o deslocamento de um fluido newtoniano. Através de uma simples abordagem experimental, uma solução de material viscoplástico ou newtoniana incialmente armazenada em um reservatório é instantaneamente liberada. As imagens do escoamento são capturadas durante o teste de duas maneiras diferentes. Uma é feita utilizando uma câmera CCD e a outra é através da Velocimetria por Imagem de Partícula. A partir das imagens obtidas pela câmera CCD, obtém-se um mapa do escoamento, com as suas respectivas velocidades, nível de líquido, formato das interfaces ar-líquido e distância percorrida pelo material são observadas. Já os resultados obtidos com o PIV, são para determinar o campo de velocidade dos momentos iniciais do Dam Break Flow para os diferentes tipos de materiais estudados. Neste trabalho, é mostrado que a plasticidade do material tem total influência sobre a distância alcançada pelo escoamento e também resultam em instabilidades ao longo do mesmo. Foi ainda identificado que o fluido viscoplástico alcança velocidades iniciais maiores que o caso newtoniano. Porém, no decorrer do escoamento, decrescem rapidamente. Quando analisado o caso viscoplástico para um leito com rugosidade, nota-se que para uma superfície lisa, há deslizamento do material de forma significativa para altos valores de plasticidade. Através da análise com PIV, foi constatado que a velocidade de frente de onda é um pouco menor do que a velocidade máxima obtida pelo escoamento. Palavras chave: Dam Break Flow, material viscoplástico, PIV, plasticidade, deslizamento.

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44

McConney, Michael Edward. "Learning and applying material-based sensing lessons from nature." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29749.

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Thesis (Ph.D)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Tsukruk, Vladimir; Committee Member: Shofner, Meisha; Committee Member: Srinivasarao, Mohan; Committee Member: Thio, Yonathan; Committee Member: Weissburg, Marc. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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45

Ley, J. D. "An environmental and material flow analysis of the UK steel construction sector." Thesis, Cardiff University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504959.

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46

Kuravi, Sarada. "Numerical Study of Encapsulated Phase Change Material (EPCM) Slurry Flow in Microchannels." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4093.

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Heat transfer and flow characteristics of phase change material slurry flow in microchannels with constant heat flux at the base were investigated. The phase change process was included in the energy equation using the effective specific heat method. A parametric study was conducted numerically by varying the base fluid type, particle concentration, particle size, channel dimensions, inlet temperature, base heat flux and melting range of PCM. The particle distribution inside the microchannels was simulated using the diffusive flux model and its effect on the overall thermal performance of microchannels was investigated. Experimental investigation was conducted in microchannels of 101 [micro]m width and 533 [micro]m height with water as base fluid and n-Octadecane as PCM to validate the key conclusions of the numerical model. Since the flow is not fully developed in case of microchannels (specifically manifold microchannels, which are the key focus of the present study), thermal performance is not as obtained in conventional channels where the length of the channel is large (compared to length of microchannels). It was found that the thermal conductivity of the base fluid plays an important role in determining the thermal performance of slurry. The effect of particle distribution can be neglected in the numerical model under some cases. The performance of slurry depends on the heat flux, purity of PCM, inlet temperature of the fluid, and base fluid thermal conductivity. Hence, there is an application dependent optimum condition of these parameters that is required to obtain the maximum thermal performance of PCM slurry flows in microchannels.
Ph.D.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Mechanical Engineering PhD

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47

McClure, Janis Elizabeth. "The design of material systems flow for sustainable development in Northern Ireland." Thesis, University of Ulster, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413861.

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48

Agarkar, Kedar G. "Flow path design and reliability of automated guided vehicles in material building." Cincinnati, Ohio : University of Cincinnati, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=ucin1089661534.

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49

Dunatunga, Sachith Anurudde. "A nonlocal dense granular flow model implemented in the material point method." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/88386.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 63-65).
A nonlocal model for dense granular flow is implemented in the material point method (MPM), an extension of the finite element method (FEM) for solid mechanics. The nonlocal model used has shown great predictive capability for dense flows when implemented in the finite element framework, but limitations of FEM prevent application of the model to truly large scale, inhomogeneous deformations. We show that these FEM results may be replicated in the MPM framework through the solution of a vertical chute flow, and allows for future work utilizing the strengths of MPM for larger and more complex flows.
by Sachith Anurudde Dunatunga.
S.M.

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50

Yeh, Yi-Liang, and 葉怡良. "Output-Oriented Indicators for Material Flow Analysis－The Case of Industrial Waste Generation." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/44479032286040941591.

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碩士
國立臺北大學
自然資源與環境管理研究所
98
In recent years, the environmental protection consciousness raised. The waste reduction is an important issue now. For make better planning and management of waste, understanding the output before reduce industrial waste is in need. This study is update the material flow analysis database, and focus on output-oriented indicators of industrial waste generation. When compare this study with literature review estimate of industrial waste generation, perceive it different. Direct material input (DMI, input-oriented) and domestic processed output (DPO, output-oriented) are the two indicators the most frequently found in the literature. This study attempt to amend material flow analysis output-oriented indicator, taking by-products and underground economy into account of material flow analysis was not considered in Taiwan. Four indicators for measuring the by-products recycling are proposed: use rate of recycle by-product (URRB), recovery rate of production by-product (RRPB), by-product use time (BUT), recovery rate of by-product (RRB). The results show industrial waste generation amount about 19 million metric tons in 2008. The underground economy of industrial waste generation about 3 million metric tons, it total about 16.1% of industrial waste generation amount. In add indicators for measuring the by-products recycling, recovery rate of production by-product (RRPB) were estimate about 60.6 %, that recovery rate of by-product has been over half. The highest of use rate of recycle by-product (URRB) about 9.8%, there still exists considerable room for the improvement in increase efficiency.

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