• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 325
  • 212
  • 69
  • 43
  • 28
  • 25
  • 19
  • 13
  • 10
  • 9
  • 7
  • 7
  • 5
  • 5
  • 5
  • Tagged with
  • 864
  • 345
  • 343
  • 138
  • 134
  • 130
  • 113
  • 104
  • 100
  • 89
  • 72
  • 61
  • 56
  • 52
  • 51
  • 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.
81

Factory safety in Wisconsin 1878-1911

Madden, Daniel Richard. January 1968 (has links)
Thesis (M.A.)--University of Wisconsin, Madison, 1968. / Includes bibliographical references (p. 135-138).
82

Enhancement of the biodegradability of grain distillery wastewater to improve upflow anaerobic sludge blanket reactor efficiency /

Gie, Lowna-Marié. January 2007 (has links)
Thesis (MSc)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.
83

Development of a complete process integration framework for wastewater minimisation in batch processes

Gouws, Jacques Francois. January 2009 (has links)
Thesis (Ph.D.(Chemical Engineering))--University of Pretoria, 2008. / Summary in English. Includes bibliographical references.
84

Manufacturing execution systems Grundlagen und Auswahl /

Louis, Philipp. January 2009 (has links)
Thesis (Ph. D.)--Universität Marburg, 2008. / "Gabler edition wissenschaft."
85

The education of children engaged in industry in England, 1833-1876

Robson, Adam Henry. January 1931 (has links)
"Thesis approved for the degree of doctor of philosophy in the University of London." / Bibliography: p. 217-227.
86

A study of the factors which influence the shifting of blue-collar workers into first line supervision

Schneidmiller, Kurt W., January 1966 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1966. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
87

Comparison between thermophilic and mesophilic aerobic biological treatment of a synthetic organic waste /

Streebin, Leale E. January 1968 (has links)
Thesis (Ph. D.)--Oregon State University, 1968. / Typescript (photocopy). Includes bibliographical references (leaves 84-88). Also available on the World Wide Web.
88

Modelling, parameter estimation, optimisation and control of transport and reaction processes in bioreactors.

ŠTUMBAUER, Václav January 2016 (has links)
With the significant potential of microalgae as a major biofuel source of the future, a considerable scientific attention is attracted towards the field of biotechnology and bioprocess engineering. Nevertheless the current photobioreactor (PBR) design methods are still too empirical. With this work I would like to promote the idea of designing a production system, such as a PBR, completely \emph{in silico}, thus allowing for the in silico optimization and optimal control determination. The thesis deals with the PBR modeling and simulation. It addresses two crucial issues in the current state-of-the-art PBR modeling. The first issue relevant to the deficiency of the currently available models - the incorrect or insufficient treatment of either the transport process modeling, the reaction modeling or the coupling between these two models. A correct treatment of both the transport and the reaction phenomena is proposed in the thesis - in the form of a unified modeling framework consisting of three interconnected parts - (i) the state system, (ii) the fluid-dynamic model and (iii) optimal control determination. The proposed model structure allows prediction of the PBR performance with respect to the modelled PBR size, geometry, operating conditions or a particular microalgae strain. The proposed unified modeling approach is applied to the case of the Couette-Taylor photobioreactor (CTBR) where it is used for the optimal control solution. The PBR represents a complex multiscale problem and especially in the case of the production scale systems, the associated computational costs are paramount. This is the second crucial issue addressed in the thesis. With respect to the computational complexity, the fluid dynamics simulation is the most costly part of the PBR simulation. To model the fluid flow with the classical CFD (Computational Fluid Dynamics) methods inside a production scale PBR leads to an enormous grid size. This usually requires a parallel implementation of the solver but in the parallelization of the classical methods lies another relevant issue - that of the amount of data the individual nodes must interchange with each other. The thesis addresses the performance relevant issues by proposing and evaluation alternative approaches to the fluid flow simulation. These approaches are more suitable to the parallel implementation than the classical methods because of their rather local character in comparison to the classical methods - namely the Lattice Boltzmann Method (LBM) for fluid flow, which is the primary focus of the thesis in this regard and alternatively also the discrete random walk based method (DRW). As the outcome of the thesis I have developed and validated a new Lagrangian general modeling approach to the transport and reaction processes in PBR - a framework based on the Lattice Boltzmann method (LBM) and the model of the Photosynthetic Factory (PSF) that models correctly the transport and reaction processes and their coupling. Further I have implemented a software prototype based on the proposed modeling approach and validated this prototype on the case of the Coutte-Taylor PBR. I have also demonstrated that the modeling approach has a significant potential from the computational costs point of view by implementing and validating the software prototype on the parallel architecture of CUDA (Compute Unified Device Architecture). The current parallel implementation is approximately 20 times faster than the unparallized one and decreases thus significantly the iteration cycle of the PBR design process.
89

Saving Animals and the Land: Uniting the American Animal Rights and Environmental Movements of the Late Twentieth Century

Schmidt, Kelsey 01 August 2017 (has links)
The following research explores the growing stability of the relationship between the modern American animal rights and environmental movements in the aftermath of the 1960s counterculture. The movements have traditionally been considered by scholars in their separate contexts, because the movements had a tenuous and inconsistent relationship throughout their early histories. While the separate consideration of the movements may have been more appropriate for research prior to the 1960s, the movements became increasingly intertwined through various influences of the counterculture. The counterculture introduced new philosophies, utilitarianism and deep ecology, to the movements that united them through their mutual distaste for anthropocentrism and industrialization. The counterculture also provided animal rights and environmental advocates with alternative lifestyles with which to promote their goals and affect real change. The movements began to most clearly unite in their mutual campaigns against the intensive animal farming industry, more controversially and widely known as “factory farming.” Both movements utilized the philosophies introduced to their movements to argue against the moral ills of the industry. Hence, they identified a need to actively combat the effects of the meat industry and have since advocated a widespread adoption of the vegetarian lifestyle among the American public.
90

Preparação e caracterização de biofilmes à base de manipueira para imobilização de caulinita intercalada com ureia

Schllemer, Magalí Aparecida 31 July 2013 (has links)
CAPES / A problemática da geração de resíduos industriais vem se agravando, principalmente pelo fato de que somente uma pequena parcela desses resíduos é corretamente tratada e devidamente destinada em locais próprios. Um exemplo de resíduo com grande potencial poluidor é a manipueira, efluente líquido gerado em grandes quantidades no processamento de mandioca para a produção de farinha e de fécula. A manipueira contém uma elevada carga orgânica na sua composição, com alto teor de fécula residual, resultante do baixo rendimento do processo de extração. Outro grande problema ambiental é a perda de nutrientes aplicados no solo por meio de fertilizantes, principalmente do nitrogênio, decorrente dos processos de lixiviação pela água das chuvas e volatilização pelo aquecimento do solo, que trazem prejuízos financeiros aos agricultores e danos ambientais pelo excesso de nutrientes levados aos corpos hídricos. Aliando-se essas duas questões, o objetivo desse trabalho foi preparar e caracterizar biofilmes à base de manipueira pura, e também de manipueira com a incorporação dos aditivos poli-(álcool vinílico) e alginato de sódio, avaliando-se assim, a influência desses aditivos nas características finais dos biofilmes. Após esta etapa, avaliou-se qual dos biofilmes produzidos obteve características compatíveis para a imobilização da caulinita intercalada com ureia, visando avaliar esse conjunto como fertilizante de liberação lenta de nitrogênio, que prioriza a liberação gradual do nutriente. A partir da caracterização da manipueira utilizada, determinou-se que a mesma possui um teor de 3% de fécula na sua composição, dessa forma, o resíduo foi utilizado como solução filmogênica para formação dos biofilmes. Esses biofilmes foram caracterizados e apresentaram baixas propriedades de barreira ao vapor de água, entretanto, os biofilmes de manipueira pura e de manipueira com poli-(álcool vinílico) possuem boas propriedades mecânicas e alta estabilidade térmica. Os biofilmes de manipueira com alginato de sódio apresentaram características mecânicas inferiores aos citados acima e com menor estabilidade térmica. A partir das características apresentadas, o biofilme de manipueira pura foi escolhido para ser o meio imobilizante da caulinita intercalada com ureia, onde, além da caracterização realizada como nos demais biofilmes, foi também avaliada a liberação do nitrogênio por meio de ensaios de lixiviação e de aquecimento. Observou-se que nos ensaios de lixiviação a imobilização não foi efetiva, perdendo 73,37% do nitrogênio incorporada já no menor tempo empregado no ensaio, entretanto, no ensaio de aquecimento, o biofilme de manipueira pura apresentou uma alta imobilização até 170 ºC, com uma perda de nitrogênio de somente 14,93%. A análise dos resultados mostra que os biofilmes à base de manipueira são uma alternativa viável de reaproveitamento desse resíduo, apresentando boas características, entretanto, quando o emprego é a imobilização da caulinita intercalada com ureia é necessário um maior estudo buscando meios para reduzir as perdas por lixiviação. / The problem of industrial waste generation has aggravating mainly by the fact that only a small portion of that waste is properly treated and properly designed in suitable places. An example of waste with high pollution potential is manipueira, liquid effluent generated in large quantities in manihot processing for the production of flour and starch. Manipueira contains a large organic load in its composition, with high levels of residual starch, resulting in low yield of the extraction process. Another major environmental problem is the loss of nutrients applied to the soil through fertilizers, especially nitrogen, resulting from leaching processes by rain water and volatilization soil heating, which brings financial damage to farmers and environmental damage by excess nutrients carried to water bodies. Allying these two issues, the objective of this work was to produce biofilms based on pure manipueira, and too manipueira with incorporation of additives poly (vinyl alcohol) and sodium alginate, thus assessing the influence of these additives in the final characteristics of biofilms. After this step, we evaluated which of biofilms produced consistent characteristics obtained for the immobilization of kaolinite intercalated with urea, to evaluate this set as a slow release fertilizer nitrogen, which prioritizes the gradual release of the nutrient. From the characterization of cassava used, it was determined that it has a content of 3% starch in composition, thus the residue was used as filmogenic solution for the formation of biofilms.These biofilms were described and presented barrier properties to water vapor low, however, the biofilm manipueira and pure manipueira and manipueira with poly (vinyl alcohol) have good mechanical properties and high thermal stability. Biofilms manipueira with sodium alginate showed inferior mechanical characteristics to those cited above and with lower thermal stability. From the characteristics presented, the biofilm pure manipueira was chosen to be the means of immobilizing kaolinite intercalated with urea, which, besides the characterization performed as in other biofilms was also investigated the release of nitrogen through leaching tests and heating. It was observed that the leaching tests was not effective immobilization, losing 73.37% of the nitrogen already incorporated in the shortest time employed in the assay, however, a test of heating, the biofilm pure manipueira showed high immobilization to 170 ° C, with a loss of nitrogen of only 14.93%. The analysis suggests that biofilms based manipueira are a viable reuse of this waste, with good features, however, when employment is immobilization of kaolinite intercalated with urea requires a larger study looking at ways to reduce leaching losses.

Page generated in 0.0407 seconds