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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.
101

Imagining the “Day of Reckoning”: American Jewish Performance Activism during the Holocaust

Gonzalez, Maya C 14 November 2023 (has links) (PDF)
Scholars of American Jewish history have long debated the complicity of the American Jewish community in the loss of six million Jewish lives in Europe during the Holocaust. After Hitler took power in 1933, American Jewish leaders took to the streets to protest the Nazi Party’s abuse of German Jews. Two central figures in this history are Reform Rabbi Stephen Wise and Revisionist Zionist Ben Hecht because of their wide-reaching protest movements that operated in competition with each other. Although the historiography presents Wise and Hecht's inability to unite as the product of difference, my examination of their protest performances presents a novel picture of similarity. Despite their ideological antagonism, Wise and Hecht's shared cultural identities, as both Americans and Jews, produced pageants with decidedly similar elements. The three productions studied here – The Case of Civilization Against Hitler (1934), Stop Hitler Now (1943), and We Will Never Die (1943) – were reflective of these identities. Appealing to their Americanness, they performed rituals of democratic justice. Appealing to their Jewishness, they presented Jewish prayer, iconography, and ritual related to divine justice. In highlighting the parallels in the performances, I read their actions as successful insofar as they appealed to a diverse American Jewish audience.
102

Experimental Investigations on Non-Wetting Surfaces

Stoddard, Ryan Manse 24 May 2021 (has links)
Superhydrophobic (SHS) and lubricant-infused surfaces (LIS) exhibit exceptional non-wetting characteristics that make them attractive for energy production applications including steam condensation and fouling mitigation. The dissertation work focuses on application of non-wetting surfaces to energy production using a systematic approach examining each component of surface fabrication in three functional areas. First, SHS and LIS are fabricated using robust, scalable methods and tested for durability in heated, wet conditions and under high-energy water jet impingement. Clear performance differences are shown based on surface texturing, functionalizing agent, and infused lubricant. Second, SHS and LIS are applied to tube exteriors and evaluated for their ability to produce sustained dropwise condensation in a typical power plant condenser environment. The surfaces are shown to produce heat transfer coefficients up to 7-10 times that of film-wise condensation, with condenser effectiveness of 0.92 or better compared to effectiveness of about 0.6 in conventional condensers. Third, LIS on the interior of tubes are assessed in accelerated mineral fouling conditions. LIS are shown to mitigate calcium sulfate and calcium carbonate fouling under laminar conditions. The results of the study bear profound benefits to reducing the levelized cost of condensers and water uptake in thermoelectric power plants, that currently consume about 50% of the total water use in the U.S. / Doctor of Philosophy / Creating durable, hybrid surfaces for improved steam condensation and fouling mitigation would provide substantial impact to power generation worldwide. Bioinspired, non-wetting surfaces, such as superhydrophobic (SHS) and lubricant-infused surfaces (LIS) exhibit exceptional non-wetting characteristics that make them attractive for energy applications. Each of these non-wetting technologies, however, faces durability and scalability challenges that make them unfeasible for widespread, practical adoption. As a result, decades of materials science research have stagnated in the research laboratories with limited demonstrations of dropwise condensation and fouling mitigation in static situations. The dissertation work focuses on application of SHS and LIS to energy production using a systematic approach examining each component of surface fabrication in three functional areas. First, SHS and LIS are fabricated using robust, scalable methods and tested for durability using ASTM standard static and dynamic evaluation methods. Clear performance differences are shown based on surface texturing, functionalizing agent, and infused lubricant. Second, dropwise steam condensation on the surfaces are shown to exhibit heat transfer performance an order of magnitude greater than film-wise condensation in a typical power plant condenser environment. The surfaces are shown to produce heat transfer coefficients up to 7-10 times that of film-wise condensation, with condenser effectiveness of 0.92 or better compared to effectiveness of about 0.6 in conventional condensers. This work presents for the first time, a non-dimensional correlation for a priori prediction of LIS heat transfer performance given known qualities of the LIS. Third, challenges of fouling mitigation in power plants have been studied for over a decade. This work demonstrates for the first time that LIS applied to the interior of tubes mitigate calcium sulfate and calcium carbonate fouling in both static and laminar flow conditions.
103

Tackling the current limitations of bacterial taxonomy with genome-based classification and identification on a crowdsourcing Web service

Tian, Long 25 October 2019 (has links)
Bacterial taxonomy is the science of classifying, naming, and identifying bacteria. The scope and practice of taxonomy has evolved through history with our understanding of life and our growing and changing needs in research, medicine, and industry. As in animal and plant taxonomy, the species is the fundamental unit of taxonomy, but the genetic and phenotypic diversity that exists within a single bacterial species is substantially higher compared to animal or plant species. Therefore, the current "type"-centered classification scheme that describes a species based on a single type strain is not sufficient to classify bacterial diversity, in particular in regard to human, animal, and plant pathogens, for which it is necessary to trace disease outbreaks back to their source. Here we discuss the current needs and limitations of classic bacterial taxonomy and introduce LINbase, a Web service that not only implements current species-based bacterial taxonomy but complements its limitations by providing a new framework for genome sequence-based classification and identification independently of the type-centric species. LINbase uses a sequence similarity-based framework to cluster bacteria into hierarchical taxa, which we call LINgroups, at multiple levels of relatedness and crowdsources users' expertise by encouraging them to circumscribe these groups as taxa from the genus-level to the intraspecies-level. Circumscribing a group of bacteria as a LINgroup, adding a phenotypic description, and giving the LINgroup a name using the LINbase Web interface allows users to instantly share new taxa and complements the lengthy and laborious process of publishing a named species. Furthermore, unknown isolates can be identified immediately as members of a newly described LINgroup with fast and precise algorithms based on their genome sequences, allowing species- and intraspecies-level identification. The employed algorithms are based on a combination of the alignment-based algorithm BLASTN and the alignment-free method Sourmash, which is based on k-mers, and the MinHash algorithm. The potential of LINbase is shown by using examples of plant pathogenic bacteria. / Doctor of Philosophy / Life is always easier when people talk to each other in the same language. Taxonomy is the language that biologists use to communicate about life by 1. classifying organisms into groups, 2. giving names to these groups, and 3. identifying individuals as members of these named groups. When most scientists and the general public think of taxonomy, they think of the hierarchical structure of “Life”, “Domain”, “Kingdom”, “Phylum”, “Class”, “Order”, “Family”, “Genus” and “Species”. However, the basic goal of taxonomy is to allow the identification of an organism as a member of a group that is predictive of its characteristics and to provide a name to communicate about that group with other scientists and the public. In the world of micro-organism, taxonomy is extremely important since there are an estimated 10,000,000 to 1,000,000,000 different bacteria species. Moreover, microbiologists and pathologists need to consider differences among bacterial isolates even within the same species, a level, that the current taxonomic system does not even cover. Therefore, we developed a Web service, LINbase, which uses genome sequences to classify individual microbial isolates. The database at the backend of LINbase assigns Life Identification Numbers (LINs) that express how individual microbial isolates are related to each other above, at, and below the species level. The LINbase Web service is designed to be an interactive web-based encyclopedia of microorganisms where users can share everything they know about micro-organisms, be it individual isolates or groups of isolates, for professional and scientific purposes. To develop LINbase, efficient computer programs were developed and implemented. To show how LINbase can be used, several groups of bacteria that cause plant diseases were classified and described.
104

Multistage Stochastic Decomposition and its Applications

Zhou, Zhihong January 2012 (has links)
In this dissertation, we focus on developing sampling-based algorithms for solving stochastic linear programs. The work covers both two stage and multistage versions of stochastic linear programs. In particular, we first study the two stage stochastic decomposition (SD) algorithm and present some extensions associated with SD. Specifically, we study two issues: a) are there conditions under which the regularized version of SD generates a unique solution? and b) in cases where a user is willing to sacrifice optimality, is there a way to modify the SD algorithm so that a user can trade-off solution times with solution quality? Moreover, we present our preliminary approach to address these questions. Secondly, we investigate the multistage stochastic linear programs and propose a new approach to solving multistage stochastic decision models in the presence of constraints. The motivation for proposing the multistage stochastic decomposition algorithm is to handle large scale multistage stochastic linear programs. In our setting, the deterministic equivalent problems of the multistage stochastic linear program are too large to be solved exactly. Therefore, we seek an asymptotically optimum solution by simulating the SD algorithmic process, which was originally designed for two-stage stochastic linear programs (SLPs). More importantly, when SD is implemented in a time-staged manner, the algorithm begins to take the flavor of a simulation leading to what we refer to as optimization simulation. As for multistage stochastic decomposition, there are a couple of advantages that deserve mention. One of the benefits is that it can work directly with sample paths, and this feature makes the new algorithm much easier to be integrated within a simulation. Moreover, compared with other sampling-based algorithms for multistage stochastic programming, we also overcome certain limitations, such as a stage-wise independence assumption.
105

A novel classical synthetic approach to carbon nanotubes and their functionalized derivatives

Wiredu, Bernard January 1900 (has links)
Doctor of Philosophy / Department of Chemistry / Duy H. Hua / Carbon nanotubes are allotropes of carbon comprising of one or more grapheme sheets seamlessly joined together to form a cylinder. They are classified as single-walled carbon nanotubes (SWNTs) or multi-walled carbon nanotubes (MWNTs). They have potential applications ranging from conductive and high reinforcement material components, nano interconnection in electronic devices to drug delivery in biological systems. Current methods of production are high temperature arc-discharge, laser ablation of graphitic materials and chemical vapor deposition. These methods give tubes that are impure and highly heterogeneous in length, diameter and chirality thus leading to mixture metallic and semiconducting tubes. Effective application of such carbon nanotubes requires cumbersome, harsh and expensive purification and sorting into like forms. Such treatments usually compromised the structural integrity of the tubes and hence their mechanical and electrical properties. Also pristine carbon nanotubes are insoluble in most solvents. Solubility in basic organic solvents is crucial prior to their application, which requires some level of chemical manipulation or functionalization on the tubes. Currently methods of functionalization are unpredictable and limited to few oxidation reactions. A novel rational synthetic chemical approach to [12, 12] arm-chair carbon nano tube with pre-defined diameter and length has been explored utilizing cheap and simple organic building blocks and results achieved so far have been presented in this dissertation. Two approaches were employed to form the carbon-rich beltene (32) before its final conversion to the target single-walled carbon nanotube (SWNT) 1. A survey on carbon nanotubes and their related structures including their potential applications and properties are presented in chapter 1. In the second chapter an iron template-assisted olefin metathesis via a ferrocene intermediate served as an anchor for an effective cyclization. In chapter 3, an un-assisted olefin metathesis pathway was explored. Both approaches use a series of benzyl halide carbonylation coupling and Diels-Alder reactions to synthesize some of the key intermediates. The protocol presented in this dissertation may be used to produce functionalized carbon nanotubes with predefined length and diameter tailored for specific applications to be produced in kilogram scale for the first time since its discovery in 1991. Such an approach is expected to address most if not all of the problems associated with the traditional methods of producing carbon nanotubes.
106

Pre-primary education policy between formulation and implementation : the case of Bangladesh

Profeta, Michela January 2014 (has links)
Why does the implementation of policies for educational improvement often disappoint? The literature suggests that pitfalls in the formulation stage can hamper successful implementation. This research aims to develop insights into the process of policy formulation in order to establish how this may affect subsequent policy implementation using a case study of Pre-Primary Education in Bangladesh. Uniquely, I have been able to study the development of PPE policy when it was taking place since I was directly involved in the process as a professional advisor working for a donor. The first research question investigated how the pre-primary policy was formed. This had two parts in terms of i) developing understanding of the phases of policy formulation and the stakeholders involved, and ii) analysing the discourses that informed the policy. The second research question enquired into the development of the implementation strategy and its feasibility, and compared expectations with the data available on the characteristics and impact of the initial implementation. This enabled the identification of aspects of policy formulation that shape current and future implementation. Special attention was given to the development of policy that prioritised underprivileged children throughout the process, because of the extent of unequal provision and because this was a high profile goal for educational development. The analysis of policy development derived from relevant policy documents and keyinformant interviews highlighted charismatic and politicised approaches to educational reform, which lacked the involvement of beneficiaries and those tasked with implementation. This has consequences for subsequent impact and the sustainability of the new policy. The initial implementation was generally considered inadequate and uneven by the respondents. It reflected aspirational planning linked to the EFA goals, with ambitious aims to provide a "quantitative breakthrough" in access and attainment without a realistic assessment of the resources available and the capacity to mobilise them. When the implementation strategy was updated and included in the third national programme of primary education (PEDP III), a more phased and comprehensive approach to planning was introduced. However, reports on programme implementation have identified delays and difficulties in starting PEDP III, albeit improvements between year 1 and 2 have been noted. In particular, the implementation strategies identified were insufficiently detailed and different stakeholders' needs were not properly assessed. More equitable delivery to underprivileged children remains poorly articulated. Part of the reason appears to be diminished political will and inconsistent leadership. Finally, opportunities to collaborate with the NGO service providers have not been fully exploited and the implementation planning for PEDP III appeared to have relied excessively on external expertise, with implications for the ownership and continuity of the policy on pre-school. Based on these findings, suggestions are offered to the development partners, the Government and the NGOs to improve the integration of policy and implementation strategies to increase the probability of sustained improvements in Pre Primary provision.
107

La collaboration en traduction (Crowdsourcing in Translation) : l’exemple d’un concours de traduction en ligne

Shaydullina, Gulnara 09 1900 (has links)
No description available.
108

[en] MODEL FOR THE HIGH FREQUENCY RESPONSE OF LAMINATED CYLINDRICAL SHELLS / [pt] MODELAGEM DO COMPORTAMENTO EM ALTAS FREQUÊNCIAS DE CASCAS CILÍNDRICAS LAMINADAS

CARLOS ENRIQUE RIVAS ARONI 17 March 2003 (has links)
[pt] Esta dissertação trata da modelagem do comportamento dinâmico de cascas cilíndricas laminadas numa faixa considerada de altas frequências onde o comprimento de onda é menor que a espessura da casca. Nestes casos,as teorias tradicionais de cascas tem problemas para representar com acuracidade a resposta dinâmica destas estruturas. Para superar este inconveniente,empregou-se a teoria discreta de Reddy para compósitos laminados.Esta teoria tem como característica o emprego de funções de interpolação para descrever a variação dos campos de deslocamento ao longo da espessura do laminado. Assim, discretizou-se a espessura da casca em lâminas delgadas na direção radial, impondo condições cinemáticas para cada uma delas. Por isto um estado tridimensional de tensões foi assumido para cada lâmina. Esta técnica permitiu a representação de campos de deslocamentos complexos na espessura do laminado representativos daqueles associados às ondas guiadas em altas frequências. A equação de estado que governa a dinâmica da casca foi então obtida no domínio da frequência a partir da aplicação do principio variacional, sendo empregado o método de Riccati para solucionar a mesma. A validação da metodologia proposta nesta dissertação foi feita comparando o espectro de frequência exato com aquele previsto pela teoria aproximada. Desta forma demonstrou-se que a teoria de Reddy é capaz de representar com precisão o comportamento dinâmico da casca cilíndrica na faixa de alta frequência. Além disso, os resultados obtidos na faixa de baixa frequência foram comparados pelo método dos elementos / [en] This dissertation addresses the problem of modeling the dynamic response of laminated cylindrical shells in the high frequency range -short wavelength-. In this range of frequency, traditional theories fail to provide an accurate result of the vibratory structural response; So, in order to overcome this shortcoming, we employed a model based on Reddys discrete layer-wise theory. In this method the cylindrical shell is discretized in an arbitrary number of layers in the radial direction, and a three dimensional stress state is assumed in each one. Hence, the application of this method let the representation of complexes displacement elds through the thickness of the shell. This characteristic is representative of displacement elds associated to guided waves in the high frequency range. In the frequency domain,the governing equations were written in a state space form by applying a variational principle. The solution of this state equation was obtained by employing an algorithm based on a discrete version of the Ricatti transformation.To validate the method proposed in this dissertation, comparisons of the present work to the exact wave-dispersion spectra were assessed with excellent results. It indicates that the present method can predict an accurate description of the dynamic response in the high-frequency range. In the low frequency range, the results of the theory of Reddy were compared with the nite element method and, again, a good accuracy was obtained.
109

Entre o sábio e o tolo: deslizamentos arquetípicos nas anedotas do Juḥā / The wise fool: archetype displacement in the anecdotes of Juḥā

Xavier, Luana Molena 05 December 2016 (has links)
Juḥā é personagem cômica e chamada por muitos nomes distintos, que ficou mais amplamente conhecida nos países do Oriente Médio. Esta dissertação visa à análise da composição dos deslizamentos arquetípicos nas anedotas dessa personagem e o papel desses deslizamentos na produção do cômico. Com esse fim, uma amostra das anedotas contidas na complicação \"Giha, Hoja e Nasredin\" - feita por Mussa Kuraiem - teve suas funções narrativas e mecanismos de continuidade narrativa evidenciados, de acordo com os modelos propostos na obra \"Análise Estrutural da Narrativa\". A fim de demonstrar a quebra lógica e a dissolução da narrativa como sua consequência, estudos a respeito do cômico permeiam este trabalho. Como base para o levantamento e demarcação dos arquétipos que emergem das anedotas, utilizou-se, dentre outras, a pesquisa de Hasan El-Shamy e Jane Garry acerca de arquétipos e motivos folclórico-literários. Por fim, este trabalho demonstra a sobreposição dos arquétipos do tolo e do sábio, e indica que a produção de efeito cômico é simultânea ao momento de sobreposição arquetípica e ao de quebra lógica. Concluiu-se que o cômico, nas anedotas analisadas, não está apenas vinculado ao deslizamento arquetípico, mas também ao tipo de quebra cômica (disjuntor) e à adequação da narrativa ao gênero anedótico. Constatou-se também a existência de ciclos temáticos nas anedotas do Juḥā além da ocorrência de nuances arquetípicas subjacentes ao par arquetípico tolo-sábio. / Juḥā is a comic character, called by many different names and most widely known in the Middle Eastern countries. This master\'s thesis has analyzed the structure of archetype displacements in the anecdotes of the abovementioned character, as well as the role of those displacements in the production of the comic effect. To this end, this study identified narrative functions and mechanisms of narrative continuity in a sample of the anecdotes featured in the compilation named \"Giha, Hoja e Nasredin\", organized by Mussa Kuraiem. This research relied upon works on humor in order to describe the resolution of the narrative as an eventual result of its logical rupture. Additionally, studies on archetypes and folk motifs, such as El-Shamy and Garry\'s, helped identify and outline the archetypes which emerge from the anecdotes. The results of this research show two archetypes overlapping in the anecdotes. They also indicate that humor, the logical rupture and the archetype overlap all tend to rise simultaneously from the text. This paper concludes that, particularly for the selected anecdotes, humor is not solely linked to the archetype displacement, once it also depends on the type of logical rupture (known as switch) and on how suitable the narrative is to the anecdotic literary genre. Apart from all that, this research points out to the existence of thematic cycles in the anecdotes of Juḥā, as well as complementary archetypes underlying the wise-fool archetypal pair.
110

Optimal Design of Feeding System in Steel Castings

Tavakoli, Ruhollah 20 September 2009 (has links) (PDF)
In the present study, the optimal design of feeding system in steel sand-mold castings is considered. The first part of this research includes fundamental studies on the physics of shrinkage defect formation during the casting process. The results of these studies lead to new findings on the mechanism of shrinkage defect formation, effect of melt quality on the distribution of defects within the castings and the connection between shrinkage and gases defects. The theoretical analysis of thermal criterion functions for the prediction of shrinkage defects in castings and introducing new criterion function with fewer shortcomings can be accounted as the other finding of this part. A new model was introduced in the second part of this research for the purpose of optimal design of feeding system in the shape casting processes. In this model the optimal design problem is formulated as a point-wise constrained topology optimization problem. Unlike alternative methods, the presented method does not require any predesigned feeding system as an initial guess. Using the functional analysis on the infinite-dimensional function spaces, a numerically efficient method was introduced to solve the optimal design problem in this study. By using extensive numerical experiments, capabilities and limitations of the presented method were studied in the last part of this research.

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