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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

Quantitative Ecological and Taphonomic Patterns in Late Cenozoic Mollusk-Dominated Marine Fossil Assemblages

Barbour Wood, Susan L. 27 June 2006 (has links)
Applications in paleontological research are far from being limited to taxonomic collection and identification. Nor is such research limited to working solely on fossil data. Actualistic paleontology is the study of modern or recent organisms and processes to better understand those of the past. The bulk of this body of research falls under the category of actualistic paleontology, and examines geochronological methods and error biases in dating biological specimens ranging in age from modern to thousands of years old. Although such methods are arguably not perfect, error rates of ± a few hundred to few thousand years can be extremely important when considering ecological relationships among both Holocene taxa and time-averaged paleocommunities, but quite diminished when considering implications on more traditional dating techniques for ancient strata. Regardless, understanding implications of time resolution is important in analyses of and comparisons between any biological dataset. The following chapters are united by quantitative and statistical management of data with varying levels of temporal resolution, and represent four manuscripts that either are in press or soon to be submitted for publication. / Ph. D.
342

Undersökning om implementering av återvunna ullfibrer i mattgarn : En jämförande studie om kvalitetens påverkan av återvunnen ull i mattor / Investigation of implementation of recycled wool fibers in carpet yarn

Ogbekene, Edith, Bergelin, Sandra January 2024 (has links)
Ull är en populär fiber och förekommer ofta i mattproduktion. Med hjälp av livscykelanalyser visar ullen vara en av de fibrerna som ligger i toppen av de material som har högst koldioxidutsläpp. Dock finns det en problematik vid beräkning av miljöpåverkan inom ullproduktionen som kan bidra till ett orättvist resultat. Trots det kvarstår faktumet att det finns förbättringar inom ullproduktionen samt att det är viktigt att ta vara på den ullen som annars skulle gått till förbränning. I samarbete med mattföretaget Rugvista undersöker denna studie hur implementering av 60% återvunna fibrer i mattgarn påverkar kvalitén med en målsätting att få in ull i ett cirkulärt flöde. Genom att undersöka detta spanns ett garn med 60% återvunnen ull och 40% konventionell ull på en E-spinner. Syftet var att garnet skulle nå upp de krav som Rugvista ställer på deras garn. Båda garnerna handvävdes därefter i en tvåskaftsbindning med ett inslagsripsutseende och i samma struktur för de skulle kunna bli jämförda med varandra under samma förutsättningar. Garnerna gick därefter igenom ett dragprovstest och de vävda proverna utsattes för ett modifierad martindaletest. Utifrån dragprovstestet påvisade de tillverkade garnet att de krävdes högre kraft för att nå brottspunkten, då majoriteten av protoypgarnerna klarade en kraft på 3500 cN, vilket var max kraften för Rugvistas garn. Dock gick det att se en större variation på brottpunkten till skillnad från Rugvistas garn som var mer enhetligt i deras resultat. I det modifierade martindaletestet gjordes en visuell bedömning på det vävda proverna efter dem hade blivit utsatta för 15 000 varv. Där påvisades referensmaterialet ett bättre resultat då den bevarade sitt utgångs utseende medan prototypen fick noppbildning redan efter 3000 varv samt släppte ifrån sig betydligt mer fibrer. Slutsatsen av studien blev att utifrån testningen visade prototypen att den inte möter den kvalitén som Rugvista ställer på sina mattor. Utmaningen är den korta fiberlängden hos de återvunna ullfibrerna som lätt lossnar från garnet. Studien visar även att de möjligt att tillverka ett tillräckligt starkt garn för att väva mattor i men att det krävs ytterligare forskning för att produktanpassa det till garnets förutsättningar. / Wool is an admired fiber and is frequently utilized in carpet production. According to life cycle analyses (LCA), wool shows to be one of the fibers that ranks highest in carbon dioxide emissions. However, there are challenges when calculating the environmental impact of wool production that contributes to an unfair result. This does not negate the reality that there are some areas within the wool life cycle that needs enhancement, especially when it comes to the utilization of wool that would otherwise have gone to incineration. This study, conducted in collaboration with the carpet company Rugvista, examines how 60% recycled wool fibers in carpet yarn affects the quality with the aim of getting wool into a circular economy. By investigating this, a yarn with 60% recycled wool and 40% conventional wool was spun on an E-spinner. The objective was to produce a yarn that meets Rugvista's quality standards. Both yarns were later handwoven in a weft-faced plainweave structure to allow for a fair comparison. The yarns underwent a tensile strength test, and the woven samples were subjected to a modified Martindale abrasion test. The results from the tensile test, showed that the manufactured yarns required a higher force to reach the breaking point, as the majority of the prototype yarns could withstand a force of 3500 cN, which was the maximum force for Rugvista's yarns. However, the breaking points of the manufactured yarns had a greater variation, unlike Rugvista's yarn, which demonstrated a more consistent result. In the modified Martindale test, visual assessments of the woven samples were conducted after 15 000 cycles. The reference material, Rugvista’s material, retained its original appearance, while the prototype developed a pilling surface after only 3000 cycles and released a remarkable amount of more fibers. The study concluded that the prototype did not meet Rugvista's quality standards for carpets. The primary challenge is the short fiber length of the recycled wool, which tends to detach from the yarn. While the study demonstrates the possibility of producing sufficiently strong yarn for carpet weaving, further research is necessary to optimize the product according to the yarn's characteristics.
343

Signal design for multi-way relay channels

Sharifian, Shaham 20 December 2016 (has links)
Today’s communication systems are in need of spectrally efficient and high throughput techniques more than ever because of high data rate applications and the scarcity and expense of bandwidth. To cope with increased data rate demands, more base stations are needed which is not cost and energy efficient in cellular networks. It has been shown that wireless relay networks can provide higher network throughput and increase power efficiency with low complexity and cost. Furthermore, network resources can be utilized more efficiently by using network coding in relay networks. A wireless relay network in which multiple nodes exchange information with the help of relay node(s) is called a multi-way relay channel (MWRC). MWRCs are expected to be an integral part of next generation wireless standards. The main focus of this dissertation is the investigation of transmission schemes in an MWRC to improve the throughput and error performance. An MWRC with full data exchange is assumed in which a half-duplex relay station (RS) is the enabler of communication. One of the challenges with signal demodulation in MWRCs is the existence of ambiguous points in the received constellation. The first part of this dissertation investigates a transmission scheme for full data exchange in MWRC that benefits from these points and improves its throughput by 33% compared to traditional relaying. Then an MWRC is considered where a RS assists multiple nodes to exchange messages. A different approach is taken to avoid ambiguous points in the superposition of user symbols at the relay. This can be achieved by employing complex field network coding (CFNC) which results in full data exchange in two communication phases. CFNC may lead to small Euclidean distances between constellation points, resulting in poor error performance. To improve this performance, the optimal user precoding values are derived such that the power efficiency of the relay constellation is highest when channel state information is available at the users. The error performance of each user is then analyzed and compared with other relaying schemes. Finally, focusing on the uplink of multi-way relay systems, the performance of an MWRC is studied in which users can employ arbitrary modulation schemes and the links between the users and the relay have different gains, e.g. Rayleigh fading. Analytical expressions for the exact average pairwise error probability of these MWRCs are derived. The probability density function (PDF) and the mean of the minimum Euclidean distance of the relay constellation are closely approximated, and a tight upper bound on the symbol error probability is developed. / Graduate
344

Images and identities in the funerary art of Western Anatolia, 600-450 BC : Phrygia, Hellespontine Phrygia, Lydia

Draycott, Catherine M. January 2010 (has links)
The dissertation analyses the reliefs and paintings on thirty-one different tombs in Western Anatolia erected between 600 and 450 BC, in order to illuminate the ways in which non-Greek elites were identified on their memorials. The tombs from three areas are treated: Phrygia, Hellespontine Phrygia and Lydia, where the primary language groups were Phrygian, Mysian and Lydian. There is little literary evidence for these regions, and what there is tends to focus on political developments. Descriptions of people and society are few, and tend to represent them from an outside perspective, grouping them according to cultural characteristics which differentiate them from Greeks. It is clear, however, that the regions were important, prosperous places, controlled by illustrious grandees and land marked with a relatively high proportion of monumental tombs. Of these monumental tombs, there is a relatively high number decorated with striking and articulate images. There is much to be gained from examining the images on these tombs, as ‘indigenous’ sources for how elite Western Anatolians described themselves. Previous approaches to the tombs and their images have tended to look at them individually or in smaller groups, and to concentrate on the transmission and reception of Persian and Greek culture in the Achaemenid provinces. This dissertation contributes a broader comparative study of the decorated tombs, focussing on the kinds of statuses the images represent and the cultural forms these took. By comparing the various methods of self-representation, it clarifies patterns of identities in Western Anatolia and their relationship to historical circumstances. The dissertation is divided into five chapters. An introduction outlines the scope and sample, the historical background, previous studies of the monuments, the definition of ‘identity’ and the methods of analysis adopted here. Three case study chapters present the regions and the decorated monuments within them. A concluding chapter synthesises three aspects: social identities (roles and spheres of life represented); geographic and chronological patterns; and cultural affiliations and orientations. The dissertation concludes that a tension between Persian identities and local traditions is evident in some of the tomb images, which relates to the political upheavals in Western Anatolia and the Aegean at the time of the Persian Wars.
345

Organisation spatiale et vie rurale sur le Piémont du Haut Atlas Occidental : cas des vallées d'Imintanoute, Province de Chichaoua (Maroc) / Spatial Organization and Rural Life on the Piedmont of Western High Atlas : the Case of the Imintanoute Valleys, Province of Chichaoua (Morocco)

Anjar, Lahsen 17 December 2012 (has links)
Les vallées d'Imintanoute offrent un exemple des vallées montagnardes du Haut Atlas occidental en crise. Ayant longtemps été considéré par ses habitants comme un « espace refuge », le pays d'Imintanoute apparaît, aujourd?hui, comme une « zone d'émigration » par excellence. Malgré une certaine diversification des cultures, occupant l'espace irrigué (bled targa) du fond des vallées et la culture céréalière pluviale d'orge du bled bour* (espace de culture pluviale), associée à un élevage et à une arboriculture diversifiée (amandiers et oliviers) comme source de revenu complémentaire de la paysannerie, actuellement, des signes de crise apparaissent de façon évidente. L'agriculture de subsistance souffre de la sécheresse persistante, du manque d'irrigation, d'un rendement à l'hectare très faible, d'une arboriculture en cours de dégradation et d'un élevage toujours en déclin. La collectivité traditionnelle et l'espace imintanoutiens n'ont pas non plus échappé aux mutations profondes. La majorité des vieux systèmes d'irrigation (la naoura et la sania) a été laissé à l'abandon ou remplacé par la motopompe. Cette technique moderne a transformé le paysage du bled targa voire du bled bour*. Tous les villages sont touchés aujourd'hui par l'émigration sans exception. Beaucoup de jeunes quittent leurs douars pour cause de pauvreté. Aujourd'hui, de nouvelles structures socio-économiques, culturelles et politiques ont changé les comportements et les modes de vie des populations. Face aux transformations, l'espoir repose sur la nouvelle autoroute Marrakech-Agadir et sur d'autres projets encore afin de redynamiser l'économie de façon à améliorer la qualité de vie des Aït Imintanoute. / Imintanoute valleys constitute an example of mountain valleys in Western Atlas undergoing severe crisis. Long considered a "place of refuge" by its inhabitants, the Imintanoute area - with its three aspects: mountain, piedmont and plain - now appears as a major "expulsion zone".Even though agriculture has diversified to some extent - based in the irrigated zones (bled targa) at the bottom of valleys and on the rainfed barley crops of the bled bour* (rainfed agricultural area), together with breeding and diversified fruit tree crops (almond and olive trees) as a source of complementary income for farmers - obvious signs of crisis appear today. Subsistence agriculture suffers from persistent draughts, lack of irrigation, a very low average yield rate per hectare, the gradual degradation of fruit tree crops and the decline of breeding. The traditional community and the area of Imintanoute have undergone profound changes. Most of the old irrigation systems (naoura and sania) have been abandoned or replaced by power pumps. That modern technology has transformed the landscape of the bled targa and possibly even of the bled bour*. All villages without exception are affected by emigration. Many young people are driven out from their douars by poverty. Today, new social, economic, cultural and political structures have changed the behaviours and the ways of life of the populations. In view of those changes, hope rests on the new motorway from Marrakech to Agadir and on still other projects to redynamize the economy and thus improve the quality of life of the Aït Imintanoute.
346

The Mississippi River Delta Basin and Why We are Failing to Save its Wetlands

Boudreaux, Lon, Jr. 08 August 2007 (has links)
Every thousand years or so, when the Mississippi River's sediment load lengthened and blocked the River’s route to the Gulf of Mexico, the mother stream changed course completely, finding a shorter route to the sea. Then, it built a new delta, thus spreading the gift of land creation along a wide coastline and creating the bayou region of Louisiana. However, this ancient, natural process was gradually halted by the arrival of man who settled across the River's natural floodplain (delta) and constructed levees and other structures to control the great Mississippi River. Since the 1930s, the Mississippi River Delta Basin and the coast of Louisiana have been literally losing ground. The decline of this environment is now affecting, and will continue to affect, our nation's economy, infrastructure, culture, and safety. Moreover, efforts to fix this problem are not working. My research and this thesis will address the issue of how plans without action have appeased Louisianans while the nation looses vital wetlands daily.
347

La déchetterie, espace de concurrence entre recyclage et récupération. Approche ethnopragmatique du rapport des hommes aux déchets / The dump area of competition between recycling and recovery. Ethnopragmatique approach the ratio of men to waste

Pacreau-Hervouette, Fanny 13 December 2013 (has links)
À l’heure du recyclage et du tri, les déchetteries, outils de leur mise en œuvre, sont investies par nombre d’acteurs en quête d’objets à récupérer. Cette recherche, sollicitée par une collectivité territoriale considérant qu’une gestion optimisée des déchets implique la prise en compte de facteurs humains, s’inscrit dans le champ de la demande sociale. L’exploration anthropologique de l’univers des déchets permet de compléter les analyses techniques et scientifiques plus anciennes. Ce travail rend compte de la nécessité d’appréhender par une démarche ethnopragmatique les discours sur les pratiques instituées à la déchetterie et celles qui s’y sont spontanément greffées, les pratiques informelles. Abordant les enjeux de légitimité et ontologiques qui ont prévalu à la mise en concurrence de pratiques vouées à un même objectif, celui de donner une seconde vie aux déchets, cette recherche repose sur un examen attentif de l’ordinaire d’une déchetterie et sur une étude du langage écrit ou oral des acteurs concernés. Elle se focalise aussi sur le sens donné, dans l’ordinaire des acteurs mais dans un contexte plus large de crise environnementale et de critique de la société de consommation, à l’acte de jeter et à celui de réhabiliter. Elle expérimente tant dans l’investigation que dans la manière d’en rendre compte, la mise en présence d’expériences de terrains d’enquête différenciés. Elle propose ainsi une mise en abyme des cadres de définition et de pensée circonscrits par le terrain d’enquête initial. Elle approfondit les connaissances sur les comportements individuels, les jeux d’acteurs en lien avec les déchets. Elle affine la compréhension des organisations publiques et privées, de leurs stratégies, de processus de décision, de la capacité de changement en matière de politique déchet. / At the time of recycling and sorting , waste sorting , tools implementation , are invested by many actors in search of items to collect . This research, requested by a local authority whereas optimized waste management involves consideration of human factors, is in the field of social demand. The anthropological exploration of the universe of waste can complete the technical and scientific older analyzes . This work reflects the need to understand the process by ethnopragmatique discourse practices established for disposal and those that are spontaneously grafted informal practices . Addressing issues of legitimacy and ontological that prevailed in the competition practice dedicated to the same goal , that of giving a second life to waste , this research is based on a careful examination of the ordinary and dumped on a study of written or spoken language stakeholders. It also focuses on the meaning given in the ordinary players, but in a broader context of environmental crisis and critique of consumer society, the act of throwing and than rehabilitate . She experimented both in the investigation in the way of realizing it, the bringing together experiences of differentiated land survey . It proposes a formal definition abyss frames and thought circumscribed by the initial field survey. It extends the knowledge on individual behavior , games players in connection with the waste. It refines the understanding of public and private organizations, their strategies, decision-making, the ability to change in waste policy.
348

Kázání na rovině v podání svatého Ambrože a svatého Cyrila z Alexandrie / Theologic reflection and comparision between commentaries of the Sermon on the Plain according to Ambrose and Cyril of Alexandria

KAŠKA, Pavel January 2019 (has links)
The thesis deals teologic comparison of two patristic commentaries of the Sermon on the Plain from Gospel of Luke - by saint Ambrose and by saint Cyril of Alexandria. Both autors are excerpts from their commentaries of Gospel of Luke. At first are outlined life and literary work of both authors and later an analysis of both texts from the point of view of selected principal theological topics is made. After that the two theological views are compared to the Sermon on the Plain, outlining the initial idea of both autors.
349

Sistemas de informa??es para a gest?o estrat?gica das IES-privadas / Information systems for the strategical management of the private higher education

Cella, Antonio Sergio 17 October 2006 (has links)
Made available in DSpace on 2016-04-04T18:36:24Z (GMT). No. of bitstreams: 1 Antonio Sergio Cella1.pdf: 2252773 bytes, checksum: b07b9322f50735c7330ef7a789c64317 (MD5) Previous issue date: 2006-10-17 / Research on the use of the information systems for the strategical management of the Private Higher Education. They are argued, first, the historical antecedents of higher education in Brazil, the question of the privatization of education, the regulation of the private higher education and the performance at period from 1994 to 2004. Shows the necessity of the private institutions to adopt a management directed toward the strategical performance, the elaboration of the Plan of Institutional Development and the development and implantation of a model of institutional strategical planning. After that, the categories of the information systems, the proposal of a model of strategical information system with its functional structure and applicabilities are demonstrated, the proposal of a management information system and the importance of the evaluation systems and strategical control. Finally, it is concluded presenting the results and suggestions of future studies. / Pesquisa sobre a utiliza??o dos sistemas de informa??es para a gest?o estrat?gica das Institui??es de Ensino Superior-Privadas. Discutem-se, primeiramente, os antecedentes hist?ricos do ensino superior no Brasil, a quest?o da privatiza??o do ensino, a regulamenta??o das IES privadas e o desempenho da educa??o superior no per?odo de 1994 a 2004. Demonstra-se a necessidade das institui??es privadas adotarem uma gest?o voltada para o desempenho estrat?gico, a elabora??o do Plano de Desenvolvimento Institucional e o desenvolvimento e implanta??o de um modelo de planejamento estrat?gico institucional. Em seguida, demonstra-se a categoria dos sistemas de informa??o, a proposta de um modelo de sistema de informa??es estrat?gicas com sua estrutura funcional e aplicabilidades, a proposta de um sistema de informa??es gerenciais e a import?ncia dos sistemas de avalia??o e controle estrat?gico. Finalmente, conclui-se apresentando os resultados e sugest?es de estudos futuros.
350

Application of Remote Sensing in Floodway Delineation

Clark, Robin B. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / Population pressures on the land resources of Arizona have led to the sale and development of areas subject to flooding and because of the inadequacy of land use controls, the area is open to various land speculation schemes and unplanned subdivision growth. A floodplain delineation project was conducted for the planning department of Cochise County, Arizona, in which imagery acquired by earth resources technology satellite (ERT-1) and by high-altitude aircraft was employed. Parameters of the analysis included soils and geomorphology, vegetation, hydrologic calculations, and historical data. Floodplain soils lack developed b horizons, as compared to older, more mature soils not subject to flooding. General soil maps can only be used as guidelines, but a detailed soil survey can add significantly to the accuracy of image interpretations. Erosion-affected soil tones in areas adjacent to active channels proved beneficial in that the heightened contrast served to enhance resolution of vegetation-type boundaries. Hydrologic calculations were done based on valley cross-sections surveyed at two-to-three mile intervals. The historic data input into the system of floodplain delineation is dependent on the location of high-water marks and on obtaining a record of the amount of rainfall which resulted in the high-water mark.

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