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Integrated Process Design and Techno-Economic Analysis of A Grape Pomace BiorefineryJin, Qing 09 September 2020 (has links)
Grape pomace (GP) is one of the most abundant and underutilized fruit-derived wastes. GP is generated during winemaking, occupying over 60% of the total solid winery wastes. GP may cause serious environmental problems if it is not properly handled. On the other hand, it is rich in valuable compounds that are worthy of recovery. Although research has been working on GP upgrading, the utilizations are limited to producing a single product (e.g., grape seeds oil or polyphenol powders), which leads to large volumes of secondary wastes left. Therefore, the goal of this study is to develop an integrated process for the comprehensive utilization of GP by the production of multiple value-added products and evaluate its economic feasibility at a commercial scale. First, the chemical composition of different industrial GPs was analyzed to lay the foundation for the process design. Based on the analyzed chemical composition, an integrated process was developed to produce grape oil, polyphenols, and biofuels from GP. In this process, GP was extracted by hexane to produce oil, followed by aqueous ethanol solution extraction to obtain polyphenols. The solid residue rich in structural carbohydrates was then pretreated by alkali to partially remove lignin and enzymatically hydrolyzed to produce monomer sugars. The produced sugars were used as feedstock to produce acetone, butanol and ethanol (ABE) through anaerobic fermentation. Under the optimized conditions, the process was able to produce 71.9 g crude oil, 322.8 g crude polyphenols (equivalent to 72.6 g gallic acid), and 20.7 g ABE from 1 kg dry GP. Besides the valuable products, the process co-generated a large amount (50% of input GP biomass) of secondary waste, which is rich in lignin. Therefore, we further converted the secondary waste to biochars and evaluated their potential application in water purification by removing lead (Pb) from contaminated water. Based on the results, the produced biochar showed a high Pb adsorption ability (134 mg/g), with 66.5% of lead removal achieved within the first 30 min. Experimental and modeling results indicated that both physisorption and chemisorption mechanisms were involved in the Pb adsorption of the biochar. Finally, techno-economic analysis was conducted to evaluate the economic feasibility of the integrated processing of GP into oil, polyphenols, and biochar at an industrial scale. The results showed that compared with generating of single product or dual products, the integrated process aiming to produce multiple products had the best economic performance with the net present value (NPV), internal rate of return (IRR), and payback period of $135.0 million, 47.5%, and 1.8 years, respectively. Sensitivity analysis showed that plant capacity and polyphenol selling price had major impacts on process economics. Therefore, a suggestion for implementing this integrated process is to invest more in the polyphenol production and purification process to generate high-quality polyphenols with a high selling price and running the plant with a large capacity. Overall, we explored a novel integrated process that aims to produce multiple value-added products to increase the economic gain for the wine industry, and at the same time, potentially reduce the environmental burdens caused by GP disposal. / Doctor of Philosophy / During wine making, a large amount of solid waste is generated, and the major one is called grape pomace (GP). GP is mainly consisted of grape skins, seeds, and some stems. Normally, GP is discarded as waste; however, if it is not handled properly, GP may cause serious damages to the environment such as contaminating soil and stream water. On the other hand, GP has valuable compounds that could be recovered for other applications. Previous researchers used GP to produce a single product, which still leads to a large amount of components not used. Therefore, the aim of the current study is to design a process to comprehensively utilize GP to produce multiple value-added products. The developed process can produce grape seed oil, polyphenols, and biofuels from GP. The solid residue generated from the designed process was further converted into biochar, which can be used as an excellent adsorbent to remove lead (Pb) from contaminated water. Based on the economic model results, the developed process to convert GP into grape seed oil, polyphenols, and biochar could be a promising investment at an industrial scale. Generally speaking, various valuable products were obtained from low value GP waste, which could not only reduce the potential environmental problems caused by waste disposal, but also provide different value-added products for food, pharmacy, chemical, and energy industries.
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Integrated processing of brewer's spent grain into value-added protein feedstuff and cellulose adsorbentHe, Yanhong 16 September 2021 (has links)
Brewer's spent grain (BSG) is the major byproduct generated by the brewing industry, which contains 14–30% protein and 50–70% of fiber. Currently, BSG is predominantly used as low-value cattle feed or buried in landfills, which is a considerable loss of valuable resources, leading to economic loss and environmental problems. Although research has been done on BSG valorization, the studies are limited to producing a single product (e.g., polyphenols, ethanol, or active carbon) and without further utilization of the produced products. Besides, the economic information available about the production of value-added products from BSG is insufficient. The overall goal of this research is to develop an integrated process to convert BSG into value-added protein-rich feedstuff and cellulose absorbent. The objectives of the research detailed here were to 1) develop a process to simultaneously produce protein-rich (PP) and fiber-rich products (FP) from BSG, 2) assess the replacement of fishmeal with PP in shrimp feed, 3) evaluate the economics of the overall process of PP production at a commercial scale, and 4) explore the potential use of cellulose adsorbent obtained from the FP in removing heavy metals from contaminated water.
To attain these objectives, BSG was first subjected to a wet fractionation process to produce PP and FP using different chemical/biological treatments, where the effects of sodium hydroxide, sodium bisulfite, and a protease (Alcalase) at different concentrations were investigated. Under the optimized conditions, the produced PP contained 46% protein and less than 1% fiber. The effectiveness of using PP to replace fishmeal at increasing levels (10–70%) was then evaluated by performing shrimp feeding trials. The results showed that up to 50% of fishmeal in shrimp feed can be replaced by PP without affecting shrimp growth and feed utilization. Moving forward, a techno-economic analysis was conducted to evaluate the economic feasibility of the production of PP. The experimental conditions and results were input into the process simulation model for determining the mass and energy flows. For a processing plant with a capacity of 590 t wet BSG per day, the minimum selling price of PP to achieve a 5% return was determined to be $1044/t, lower than the price of fishmeal, indicating that the use of PP to replace fishmeal in shrimp feed could potentially reduce shrimp farming cost. The utilization of FP will further improve the economic feasibility of the fractionation process. FP was sequentially treated by dilute acid, alkali, and bleach to produce purified cellulose fibers, which were then modified by 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) oxidation to produce a cellulose adsorbent. The feasibility of the adsorbent in removing heavy metals (especially lead and manganese) from contaminated water was then investigated. Based on the results, the produced cellulose adsorbent showed high adsorption capacities for lead (272.5 mg/g) and manganese (52.9 mg/g). Overall, this study demonstrated that BSG can be upcycled into multiple value-added products via an integrated process. The outcomes of this study not only provide a low-cost and sustainable protein source to the aquaculture industry, and provide a novel adsorbent for the water treatment industry, but also offer alternative ways for the brewing industry to manage BSG. / Doctor of Philosophy / Brewer's spent grain (BSG) is the major byproduct generated by the brewing industry. Currently, BSG is predominantly used as low-value cattle feed or buried in landfills due to its high fiber and low protein contents, which is a considerable loss of valuable resources. Besides, raw BSG contains other nutrients and high water content, the inappropriate management of BSG may introduce environmental concerns. Though technologies have been investigated to valorize BSG by extracting protein from it, the process scaled-up is limited by the high drying costs of wet BSG, heavy chemical consumptions, and a large amount of fiber residue. The overall goal of this research is to develop an integrated process to convert BSG into value-added protein-rich feedstuff and cellulose absorbent.
In this study, we developed and optimized a process to produce protein and fiber products from wet BSG. The protein content of the produced protein product was doubled and the fiber content was reduced significantly compared with the raw BSG, which lighted the use of the protein product as an alternative to fishmeal. Fishmeal is an expensive aquafeed ingredient, the aquaculture industry is looking for alternatives to replace it. Herein, we investigated the effectiveness of the protein product as an alternative to fishmeal by conducting shrimp trials. A further economic analysis was conducted to evaluate the economic feasibility of the proposed process for protein and fiber production from BSG. In addition, the fiber product was used for producing a cellulose adsorbent to remove heavy metals from contaminated water.
Overall, this study demonstrated that BSG can be upcycled into multiple value-added products via an integrated process. The outcomes of this study not only provide a low-cost and sustainable protein source to the aquaculture industry, and provide a novel adsorbent for the water treatment industry, but also provide alternative ways for the brewing industry to manage BSG.
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Toward a Unified Computer Learning Theory: Critical Techno ConstructivismSanders, Bryan Philip 01 January 2019 (has links) (PDF)
Why did we ever purchase computers and place them along the wall or in the corner of a classroom? Why did we ever ask students to work individually at a computer? Why did we ever dictate that students should play computer games or answer questions built from a narrow data set? And why are we still doing this with computers in classrooms today?
This approach has contributed to a systemic problem of low student engagement in course materials and little inclusion of student voice, particularly for traditionally underrepresented students. New transformational tools and pedagogies are needed to nurture students in developing their own ways of thinking, posing problems, collaborating, and solving problems. Of interest, then, is the predominance in today’s classrooms of programmed learning and teaching machines that we dub 21st century learning. We have not yet fully harnessed the transformational power and potential of the technology that schools already possess and that many students are bringing on their own.
This dissertation aims to address what is missing in best practices of technology in the classroom. Herein these pages will be performed a document analysis of cornerstone books written by John Dewey, Paulo Freire, and Seymour Papert. This analysis will be in the form of annotations comprised of the author’s experience as an experienced educator and researcher, and founded in the extant relevant theories of critical theory, technology, and constructivism. The three philosophers were selected for their contributions to constructivism and their urgings to liberate the student from an oppressive system. With a different approach to educational technology, students could be working towards something greater than themselves or the coursework, something with a passionate purpose derived from student inquiry. Instead of working at the computer and having a “one and done” experience, students could be actively transforming their studies and their world. And instead of reifying existing social and racial inequities outside of the classroom through the large computer purchases and the dominant culture attitudes and beliefs found in many software products and databases, we could be examining our practices and programs with a critical lens that allows us to question and seek more inclusive community strategies.
The final chapter is about asking for, pushing for, and dreaming for new kinds of schools, classrooms, software, hardware, and new ways to think about and create new opportunities for students. Mixed reality, sometimes called augmented reality, is likely the anticipated future of computers in the classroom.
We need to, very deeply and purposefully, mix up electronics with people. We are in a new era with new understandings of old issues showing up in old problems. A unified learning theory for computers, computing, and digital learning environments could help to redefine classroom spaces and class time, as well as graduation outcomes. The revolution will indeed be live on the Internet, but it will also be remixed and recreated by students organically and authentically pursuing their own truth.
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Methodologies and tools for BiPV implementation in the early stages of architectural design.Lovati, Marco 22 May 2020 (has links)
Photovoltaic technology is among the best tools our civilization has to reduce the emissions of greenhouse gas that are currently altering the atmosphere composition of our planet. The idea of using photovoltaic surfaces on the envelope of buildings is called with the acronym of BIPV (building integrated photovoltaics), it offers the advantage of producing energy in the same location of the demand for electricity. Furthermore, BIPV allows to save monetary and environmental costs by substituting building materials with photovoltaic collectors. As every technology,BIPV follows an adoption pattern that is bringing it from a very limited niche product to a pervasive one. Nevertheless, the adoption rate of BIPV appears to be slow, and the industry has offered little opportunities of business for its stakeholders over the last 20 years. There are multiple reasons for this sluggish growth, and a considerable body of scientific literature has offered potential solutions to the problem. The building industry is notoriously slow in picking up innovation, furthermore the BIPV material needs to compete with much more mature, versatile and often cheaper cladding technologies and materials. Numerous research endeavors are focusing on the development of new BIPV claddings to have diversified colors, dimensions, shapes and other properties. The argument is that the technology is not mature and thus cannot be adopted by the bulk of architects and designers. Unfortunately, the premium characteristics of these new materials often come with a higher price and a reduced efficiency, thus reducing their market potential. Other research
endeavors, among which this thesis, are focusing on the design of buildings: trying to include the use of photovoltaics into the architectural practice through education and software development. Numerous
software has been developed over the last 20 years with the aim of calculating the productivity or the economic outlook of a BIPV system.
The main difference between the existing software and the method presented here lies in the following fact: previously, the capacity and positions of a BIPV system are required as input for the calculation of
performance, in this method the capacity and positions of the BIPV system are given as the output of an optimization process. A designer whois skeptical or disengaged about the use of BIPV could be induced to avoid its use entirely by the discouraging simulation results given by the lack of a techno-economic optimal configuration. Conversely, a designer
who opt for a premium architectural PV material would, thank to the methodology shown, be able to assess the impact its unitary cost has on the optimal BIPV capacity of the building. Ultimately, the method presented provides new knowledge to the designer regarding the use of BIPV on his building, hopefully this can facilitate the spread of BIPV technology. The method described was translated into a software tool to find the best positions and number of PV surfaces over the envelope of the building and the best associated battery capacity. The tool is based on the combined use of ray-tracing (for irradiation calculation) and optimization algorithms, its use led to the following conclusions:
• BIPV is profitable under a wide range of assumptions if installedin the correct capacities
• 20% of the residential electric demand can easily be covered by PV without the need for electric storage and in a profitable way
• Despite an interesting rate of return of the investment, the payback time was generally found to be long (over 10 years)
• More research is needed to assess the risk on the investment on BIPV: if found to be low, future financial mechanisms could increase its spread despite the long payback time
• The optimal capacity in energy terms (i.e. the energy consumed on-site minus the energy used to produce a BIPV system) tends to be far higher than any techno-economic optimum
• The specific equivalent CO2 emissions for an NPV optimal system have been found to be between 70 and 123 [kg CO2 eq/MWh] under the range of assumptions applied
• The installation of optimal BIPV capacity could change the overall residential CO2 emission of -12%, +13%, -29% in England, France and Greece respectively
• despite the non optimal placement of a BIPV system compared to a ground mounted, south oriented one, and despite the noncontemporaneity of production and consumption, the BIPV still easily outperforms the energy mix of most countries when optimized for maximum NPV.
• The part of the building envelope that have the most annual irradiation (i.e. the roof) should not necessarily host the entirety of the system as other facades might have an advantage in terms of matching production and consumption times.
• when different scenarios are made in terms of techno-economic input parameters (e.g. degradation of the system, future costs of maintenance, future variation of electricity price etc..) larger capacities are optimal for optimistic outlooks and vice-versa
• the optimal capacity for the expected scenario (i.e. the 50 % ile) can be considered robust as it performs close to the optimum in optimistic and pessimistic scenarios alike.
• a reduction in price for the electric storage appears to have a positive effect on the optimal capacity of PV installed for the case study considered.
• when a group of households is optimized separately V.S. aggregated together, the aggregation have a huge positive effect on all KPIs of the resulting system: in the NPV optimal system of a case study examined the installed capacity ( +118%), the NPV ( +262.2%) and the self-sufficiency( +51%) improved thanks to aggregation.
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Direito homogêneo: harmonização, uniformização e ambivalência do direito nacional / Homogeneous law: harmonization, uniformization and ambivalence of national law.Andrade, Rogério Emilio de 14 June 2010 (has links)
No escopo de organização econômica do mundo, a globalização conduziu a uma limitação do papel das instituições públicas com relação ao mercado, haja vista a repercussão do poder econômico do capital na tomada de decisões de política econômica interna: a estruturação mundial dos mercados somente se torna plausível por meio da institucionalização de direitos no espaço dos Estados nacionais. Desse modo, os direitos nacionais tendem a uniformizar e harmonizar a regulação dada ao capital: trata-se da homogeneização dos direitos, porquanto, tendo em vista as necessidades decorrentes de uma indefectível interdependência econômica, os Estados nacionais acabam por adotar, com mais ou menos independência e criatividade, as instituições necessárias ao desenvolvimento do capital. É isso que torna a vontade planetária homogênea, por meio da artificialidade jurídica que permite ao direito se libertar dos vínculos terrestres e tradições históricas, instituindo, por assim dizer, uma espacialidade própria do direito, a espacialidade jurídica. Deixa-se, assim, o antigo nomos, que vinculava o direito aos lugares, a uma histórica e específica determinação de uma comunidade, para ir-se em direção ao novo nomos, que, estendendo-se às dimensões planetárias da tecno-economia, desliga-se dos vínculos tradicionais e assume plenamente o caráter da artificialidade. Apesar de os Estados continuarem desenvolvendo um papel importante, não se pode deixar de constatar que sua soberania econômica foi matizada: antes detinham poder absoluto em relação à economia, agora detêm poder relativo. As transformações e arranjos institucionais, que eram congruentes em nível nacional, agora estão dispersos em múltiplos níveis espaciais, pois o desempenho econômico requer que os atores sejam simultaneamente coordenados em todas as áreas espaciais, precisam ser alocados e aninhados em arranjos institucionais conectados a todos os níveis da realidade. Nesse contexto, Redes de Governo constituem um bom instrumento de política pública tanto para os países desenvolvidos quanto para os países em desenvolvimento que procuram participar do processo regulatório global e precisam reforçar sua capacidade de governança doméstica. Pode-se dizer que a partir da homogenia dos direitos pretende-se estudar três movimentos distintos e simultâneos que vêm influenciando a produção normativa dos Estados nacionais: a harmonização dos direitos, a uniformização dos direitos e a ambivalência dos direitos. Procurou-se empreender a revisão do tema escolhido na literatura existente no intuito de perquirir informações e conhecer as contribuições teóricas já produzidas pela ciência até o momento. A partir dessas contribuições teóricas, fez-se a identificação dos alicerces que permitiram dialogar com duas grandes tendências teóricas que prevalecem na análise do tema: a primeira, de cunho técnico, aposta na relevância do papel das Administrações Públicas no processo de regulação do mercado global; a segunda, de cunho político, visa a estabelecer mecanismos políticos de neutralização e compensação dos efeitos da globalização. Em linha com esses pontos, a pesquisa comprometeu-se com a realidade concreta e, simultaneamente, engajou-se com a transformação dessa mesma realidade. De conseguinte, o trabalho procurou evidenciar as formas como as forças econômicas influenciam os fenômenos legais, bem como, em sentido oposto, o direito, como instrumento político, pode e deve afetar a economia. / In the scope of the global economic organization, the international integration of markets led to a limitation of the role of public institutions regarding the markets because of the economic power repercussion of the capital in the decision-making of internal economic policy: the world structuring of markets only becomes plausible by the institutionalization of Law in the national States. Thus, the national Law tends to standardize and harmonize the regulation of the capital: it is the homogenization of the Law as the resulting needs of an economic interdependence, which leaves the national States to adopt the necessary institutions to the capital development. It is this that turns the planetary will homogeneous through legal artificiality that allows the Law gives out of the terrestrial bonds and historical traditions, instituting the legal spatiality. Free from the old nomos, which links the Law to places, to a historical and specific determination of a community, the Law gives place to the new nomos, which detaches itself from the traditional bonds and fully assumes the artificiality character by extending itself to the planetary dimensions of the techno-economy. Despite the States continue to play an important role, it should be noticed that their economic sovereignty was tinged: before, they had an absolute power over the economy, whereas they now have a relative power. The transformations and institutional arrangements that were congruent in national level are now scattered in multiple spatial levels as the economic performance requires actors to be simultaneously coordinated in all spatial areas and they need to be allocated and nested in institutional arrangements connected to all levels of reality. In that context, Government Nets constitute a good instrument of public policies both for the developed countries and for the developing countries that attempt to take part of the global regulatory process and need to reinforce their capacity of domestic governance. It can be said that from the homogeneity of the Law on, this work aims at studying three simultaneous and distinct movements that have been influencing the normative output of the national States: the harmonization, the uniformization and the ambivalence of the Law. A literature review was presented with the objective of looking for specific information as well as knowing the theoretical contributions of the field. Based on those theoretical contributions, it was possible to keep a dialogue with two important theoretical tendencies that prevail in the analysis of the subject: first, the technical theoretical tendency, supported by the relevance of the role of Public Administrations in the process of global market regulation; second, the political theoretical tendency aims at establishing political mechanisms of neutralization and compensation of the globalization effects. In line with those theoretical tendencies, this study was committed to the concrete reality and it was simultaneously engaged with the transformation of that same reality. Therefore, the study aimed at showing the ways the economic forces influence the legal phenomena and the Law, as a political instrument, can and does affect the economy.
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L'écoute en ligne. Figures du sujet écoutant et mutations des espaces musicaux sur Internet / Online listening. The Figures of the Listening Subject and The Transformations of Musical Spaces on the InternetGras, Stéphan-Eloïse 11 December 2014 (has links)
Cette recherche interroge les figures du sujet écoutant en jeu dans les mutations des espaces musicaux sur Internet de 2007 à 2014, afin de penser l’écoute en ligne dans ses spécificités philosophiques et communicationnelles. On étudie un dispositif industriel et logiciel de recherche et de recommandation musical complexe, l’interface de programmation d’ Echonest, pour en saisir les effets esthétiques, c’est-à-dire pour comprendre dans quelle mesure la culture numérique contemporaine façonne l’expérience musicale. Trois angles sont successivement abordés : une archéologie de l’écoute montre les héritages de son expérience en ligne, une étude des politiques de l’archive et de l’algorithme incite à penser les axiologies industrielles de machines du goût, enfin une analyse sémio-pragmatique met en exergue le régime fictionnel de l’écoute à l’écran. Face à l’émergence d’une forme médiatique, le streaming, ces trois temps décrivent un régime numérique contemporain de la perception (sensorium digital) comme une discipline de l’écoutable qui s’appuie sur des modes fictionnels de production de sens en ligne. / This research questions the figures of the listening subject in the context of the transformations of musical spaces on the Internet from 2007-2014, in order to consider the question of online listening from the perspective of the fields of philosophy and communications. I study the industrial and logical disposition (dispositif) of the API of The Echo Nest, a complex musical search and recommandation engine. I seek to grasp the aesthetic effects of this technoogy as a means of understanding the extent to which contemporary digital culture shapes musical experience. This is approached from three perspectives: an archeology of listening, which shows what is inherited in the online listening experience; a critical reading of the politics of digital archiving and algorithms,which incites us to think about the industrial axiologies of « machines of taste » ; and lastly, a semiotic-pragmatic analysis, which draws attention to the fictional modalities involved in mediated listening. With the emergence of music streaming as a new form of radio, this dissertation traces a contemporary regime of digitized perception (digital sensorium) that becomes a « discipline oflistenable » supported by the fictional mode of online production of meaning.
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Analyse techno-économique des chaînes opératoires lithiques du Témiscouata (Québec), durant le Sylvicole et la période de ContactEid, Patrick 01 1900 (has links)
Cette thèse porte sur l’analyse technologique d’assemblages lithiques provenant du Témiscouata dans le Bas-Saint-Laurent (Québec, Canada) et datés entre le Sylvicole moyen tardif (500 à 1000 apr. J.-C.) et la période de Contact (XVIe et XVIIe siècles apr. J.-C.). Cette région, située dans l’extrémité septentrionale de la haute vallée de la rivière Saint-Jean, possède une importante source de matière première lithique, le chert Touladi, qui a été fortement exploitée à la préhistoire et même durant la période historique par les Premières Nations. Les chaînes opératoires lithiques de cinq sites archéologiques du Témiscouata ont été analysées via l’approche technologique afin d’en reconstituer les schèmes techno-économiques et leur implication dans les modes de vie des chasseurs-cueilleurs nomades de la région.
Les industries lithiques du Témiscouata montrent l’existence de trois chaînes opératoires : la taille de pièces bifaciales, le débitage de nucléus et l’utilisation de pièces esquillées. Quant à l’outillage, il est constitué par des pièces bifaciales et des outils simples sur éclats (outils ad hoc, grattoirs et pièces esquillées). La production des outils sur éclats a été faite sur des supports issus de ces trois chaînes opératoires, mais c’est le processus bifacial qui est cependant à l’origine de la majorité d’entre eux et c’est pourquoi il occupait une place centrale dans ces industries. Les pièces bifaciales combinaient ainsi les rôles d’outils et de « nucléus » fournissant l’essentiel des supports. Les artefacts en chert local ont permis de mieux comprendre comment les technologies étaient organisées pour les besoins à une échelle locale, mais également territoriale alors que les groupes profitaient des carrières de chert Touladi pour se préparer à leurs besoins futurs, anticipés ou non. Quant aux pièces en matériaux exogènes, même si elles comptent pour une part minime des assemblages lithiques, elles ont permis d’entrevoir les stratégies économiques adoptées préalablement à l’occupation du Témiscouata, dans des contextes de rareté en matières premières lithiques de bonne qualité.
Les schèmes techno-économiques mis en œuvre par les communautés de chasseurs-cueilleurs du Témiscouata ont constitué des éléments importants de leur stratégie d’adaptation en leur fournissant l’outillage nécessaire selon les multiples contextes rencontrés au cours de leur cycle annuel de nomadisme. Ils traduisent ainsi des choix révélateurs de leurs modes de vie, de leurs modalités d’occupation des sites et de leur réalité socio-économique. / This thesis presents data and analyses on chipped stone tool techno-economic patterns of nomadic hunters-gatherers at a quarry source area in the Témiscouata region (Québec, Canada) during the latter part of the Middle Woodland (500-1000 AD), the Late Woodland (1000-1550 AD) and also the early historic period (XVIe-XVIIe centuries AD). Located in the hinterland of the Bas-Saint-Laurent region, in the upper St. John river drainage, the Témiscouata region is rich in natural resources, perhaps among the most important is an important chert outcrop. The Touladi chert is present in two main quarries and is also found in pebble form scattered in the vicinity of the surrounding lakes and rivers. We applied a technological analysis, from the technological approach in the French tradition, to five lithic collections with the objective of reconstructing the chaînes opératoires and their economic management patterns (techno-economy).
The most prominent artifacts found are of course the countless flakes which have been derived from three different chaînes opératoires: the bifacial process, the multidirectional (ad hoc) core reduction, and the use of pièces esquillées. The production of bifacial tools is the most important process in the Témiscouata lithic industries and is the one which produced most of the flakes found on the prehistoric settlements. The tool assemblage is first characterized by the bifacial tools which are primarily manufactured from tabular blocks of chert. As for the flake tools, they are mostly represented by informal (ad hoc) tools (retouched and used flakes), endscrapers and pièces esquillées. Techno-economic patterns of Touladi chert use have demonstrated that most of the flake tools were made on flake blanks derived from the bifacial process, mostly from the early and middle stages of this chaîne opératoire. The bifacial process was also segmented in time and space so that blanks and preforms could be carried throughout the territory to be used as “cores”. The two other production sequences are quite secondary based on the small amount of tools manufactured and they are far less mobile than the bifacial process. Stone tools that are made of exotic materials, even if they represent a small part of the archaeological record, reveal the patterns that prevailed while hunters-gatherers were outside the quarries zone.
The technological analysis provides empirical evidence that hunter-gatherers of the Témiscouata region adopted flexible and simple, yet efficient, techno-economical strategies. These management schemes, which use the bifacial chaîne opératoire as the central element of tool manufacturing, are well adapted to their way of life based on a generalist, seasonal and flexible subsistence economy.
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Analyse techno-fonctionnelle des industries à pièces bifaciales aux pléistocènes inférieur et moyen en Chine / Techno-functional analysis of biface-bearing industries in lower and middle pleistocene ChinaBodin, Erika 18 January 2011 (has links)
Les industries à pièces bifaciales découvertes en Chine font actuellement l’objet d’interprétations opposées. L’une d’elle, de plus en plus souvent proposée, considère les pièces bifaciales chinoises comme les témoins d’une diffusion à partir de l’Occident. Le modèle traditionnel proposant un isolement technico-culturel de l’Asie de l’Est, matérialisé la « ligne de Movius », serait alors erroné. Ce regroupement des industries à pièces bifaciales chinoises au sein du complexe « acheuléen » ne fait pas l’unanimité et l’hypothèse d’une réinvention locale est également envisagée. Ces hypothèses contradictoires reflètent les lacunes des cadres méthodologiques et conceptuels employés pour l’étude de ces industries. L’approche retenue pour cette étude vise à restituer les intentions placées dans la réalisation de l’outillage par le biais d’une analyse techno-fonctionnelle. Les sites retenus appartiennent à une période comprise entre 1Ma et 500ka : Yangwu, Gaolingpo et Nanbanshan, dans le bassin de Bose (région autonome du Guangxi Zhuang) et les sites de Lantian et Liangshan Longgangsi (province du Shaanxi).Les résultats de l’étude mettent en évidence l’existence de deux traditions techniques distinctes entre le centre le sud de la Chine. Il existe une forte variabilité entre le matériel des deux régions, perceptible par la quasi-absence de schèmes de débitage dans le bassin de Bose et par des différences importantes de composition de l’outillage. Mais surtout, les pièces bifaciales du centre et du sud ne montrent aucune similitude structurelle, technologique ou fonctionnelle. Bien que regroupées sous une même appellation, ces pièces sont des outils différents. Sur un plan diachronique, l’existence en Chine d’industries reposant sur des schèmes de débitage et sur des schèmes de façonnage autour de 2Ma montre la possibilité d’une évolution des lignées techniques à partir d’un substrat technique local. Après 500ka, le phénomène bifacial persiste, mais n’évoluera pas vers des formes plus techniquement investies. Sur un plan spatial, une comparaison avec le matériel bifacial découvert ailleurs en Asie montre que les industries à pièces bifaciales coréennes présentent des similitudes avec les industries chinoises postérieures à 500ka. Par contre, aucun lien n’apparait avec les phénomènes bifaciaux indiens et mongols.Les industries à pièces bifaciales chinoises n’entretiennent pas de lien avec le complexe acheuléen et résultent d’un phénomène de convergence technique. Les phénomènes bifaciaux asiatiques montrent une variabilité temporelle et spatiale bien plus importante qu’habituellement envisagé. / Lately discovered Chinese biface-bearing industries are subject to opposite interpretations. Literature increasingly suggests that Chinese bifaces can be seen as a witness of diffusion from the West. The traditional model, stating a techno-cultural isolation of Asia, embodied in the “Movius Line” would thus be questioned. This assimilation of biface-bearing industries within the “Acheulian complexe” is far from achieving unanimous backing and the hypothesis of a local reinvention is also proposed. These conflicting hypotheses reveal the gaps in the methodological and conceptual frameworks used to study these industries.The chosen approach for this study aims at restoring the goals underlying the production of the tool kit through a techno-functional analysis. Chosen sites belong to a period ranging from 1Ma to 500ka : Yangwu, Gaolingpo and Nanbanshan, located in Bose basin (Guangxi Zhuang), and Lantian and Liangshan Longgangsi sites (Shaanxi province).The outcomes of this contribution bring to light the presence of a well-marked geographical discrimination between the technical traditions observed in the South on one hand and the center of mainland China on the other. A strong variability is underlined between the two areas by the virtual absence of débitage schemes in Bose basin and considerable divergence in the composition of the tool-kits. Significantly, bifacial pieces from the South and the Center show no structural, technological or functional similarities. Even though gathered under one denomination, it is clear that we are dealing with two different kinds of tools. From a diachronic perspective, the existence in China of industries relying on both débitage and shaping schemes around 2Ma indicates the possibility of bifacial technical lineage evolution from a local technical substrate. After 500ka, the bifacial phenomenon still exists but won’t evolve toward more technically invested tools. From a spatial perspective, a comparison with bifacial industries discovered elsewhere in Asia demonstrates that Korean biface-bearing industries bear similarities with Chinese industries after 500 ka. However, Chinese industries don't seem to be linked with Indian and Mongol bifacial phenomena.Chinese bifacial industries show no connexion with the Acheulian complex but rather represent a technical convergence. East-Asia bifacial phenomena involve much stronger variability through time and space than generally considered.
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Systèmes techniques et variabilité fonctionnelle des industries anciennes en Afrique de l’Est et en Europe : nouvelle approche des premières industries du Pléistocène inférieur / Technical systems and techno-fonctional variability of early stone age assemblages in East Africa and Europe. : new approach of Lower Pleistocene technologyDe Weyer, Louis 19 May 2016 (has links)
Ce travail présente une analyse des industries du Pléistocène inférieur en Afrique de l’Est et Europe pour questionner les modèles de peuplement de l’Europe. L’étude de la variabilité interne à l’Oldowayen par l’analyse des assemblages de Koobi Fora FxJj-10, Fejej FJ-1 et Olduvai DK montre des choix techniques qui influencent la sélection des matières premières pour réaliser les objectifs de production selon des modalités particulières, qui correspondent à des identités, des traditions techniques qui peuvent avoir une valeur culturelle. La comparaison avec les premiers assemblages européens est réalisée par l’étude des idustries de Barraco León, Fuente Nueva 3, Piroo Nord et Monte Poggiolo. La variabilité interne aux industries européennes est constituée des mêmes ressorts qu’en Afrique de l’Est. Les schèmes opératoires reposent sur des critères techniques précis, et les objectifs de production sont obtenus selon des modalités particulières (un système à volumes utiles indépendant dans lequel les critères techniques sont pensés pour la production d'un unique éclat, dont l'opération peut être répétée sur le nucléus si les critères techniques sont présents ; un système de production par séries d'enlèvements récurrents, dont les volumes utiles sont sélectionnés pour produire une série d'éclats récurrents). Les différentes modalités impliquent pourtant les mêmes objectifs de production, et l'analyse techno-fonctionnelle montre que les groupes d'outils potentiels ne varient pas beaucoup entre les sites. Les diférentes modalités jouent par contre un rôle très important en ce qui concerne la sélection des matières premières, allant du type de matériau aux morphologies des matrices sélectionnées, à l'inverse de l'adaptation contrainte généralement avancée. Nous considérons cet aspect comme marqueur de tradition technique et donc comme un caractère culturel. L’analyse comparée des résultats de chaque ensemble régional montre une similarité troublante, d’autant que le décalage chronologique entre l’apparition des premières industries en Afrique de l’Est et en Europe est proche d’1 Ma. Lorsque ces industries apparaissent en Europe, elles ont été remplacées en Afrique depuis près de 500 ka par une nouvelle tradition technique constituée d’un façonnage de pièces bifaciales (Acheuléen). Ainsi, les hypothèses de migrations des homininés parallèles à des stades techniques évolutifs ne semblent pas pertinentes et l’histoire du peuplement de l’Europe doit être dissociée de l’histoire de son évolution technique. Une convergence technique semble se dégager des comparaisons régionales, et fournit une nouvelle image buissonnante de l’évolution des techniques, contrairement à l’image linéaire communément admise. / This work aims to reconsider the common models for the peopling of Europe during the Lower Pleistocene from a technological point of view. We studied the variability of Oldowan assemblages from Koobi Fora FxJj-10 (East Turkana, Kenya, Fejej FJ-1 (Lower Omo Valley, Ethiopia) and Olduvai DK (Tanzania). Then we compared the results with the first evidence of Human presence in Europe, mostly known because of lithic assemblages. In Europe , we studied the lithic matérials from Barranco Leon and Fuente Nueva 3 (Spain), Pirro Nord and Monte Poggiolo (Italy). Each region show the same technological features, based on simple technical criteria applied cautiously on the cores to produce a variety of flakes. Differences appear inside each area depending of the flaking modality : independant flake production (each flake is one operation, that can be repeated on the same core as long as acurate angles are present) or reccurent flake production (continuous series of recurrent flakes). The choice of one modality or the other is playing a very important rôle in raw material selection, that influences the type and shape of raw materials selected. The selection is made on purpose, and not as an adaptation of natural constraints, as shown in most sites environment where all materials are equally available, but clear choices are made.On the other hand, flaking modality does not change the objectives of production and the techno-functional groups are very similar in all sites. We propose that this choice is a cultural trait that changes a lot what was up to now considered as low evolved and simple technology. The European peopling cannot be related to technological features. According to the data studied, there is no argument that enhance the arrival of an African population, and more arguments that sustain the technical convergence and independant development of stone tool technology during the Lower Pleistocene.
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Voltage Stability and Reactive Power Provision in a Decentralizing Energy System / Spannungshaltung und Blindleistungsmanagement bei zunehmend dezentraler Stromerzeugung - eine techo-ökonomische AnalyseHinz, Fabian 19 December 2017 (has links) (PDF)
Electricity grids require the ancillary services frequency control, grid operation, re-establishment of supply and voltage stability for a proper operation. Historically, conventional power plants in the transmission grid were the main source providing these services. An increasing share of decentralized renewable energy in the electricity mix causes decreasing dispatch times for conventional power plants and may consequently lead to a partial replacement of these technologies. Decentralized energy sources are technically capable of providing ancillary services. This work focuses on the provision of reactive power for voltage stability from decentralized sources. The aim is to answer the question of how voltage stability and reactive power management can be achieved in a future electricity system with increasing shares of decentralized renewable energy sources in an economical and efficient way. A methodology that takes reactive power and voltage stability in an electricity system into account is developed. It allows for the evaluation of the economic benefits of different reactive power supply options. A non-linear and a linearized techno-economic grid model are formulated for this purpose. The analysis reveals an increasing importance of reactive power from the distribution grid in future development scenarios, in particular if delays in grid extension are taken into account. The bottom-up assessment indicates a savings potential of up to 40 mio. EUR per year if reactive power sources in the distribution grid provide reactive power in a controlled manner. Although these savings constitute only a small portion of the total cost of the electricity system, reactive power from decentralized energy sources contributes to the change towards a system based on renewable energy sources. A comparison of different reactive power remuneration mechanisms shows that a variety of approaches exist that could replace the inflexible mechanisms of obligatory provision and penalized consumption of reactive power that are mostly in place nowadays.
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