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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.
161

Analysis Treatment Efficiencies and Emergy Analysis of Constructed Wetlands¡ÐA Case Study of Kaoping River Old Railroad Bridge Constructed Wetland

Lu, Shih-min 02 February 2007 (has links)
Constructed wetlands have been widely accepted as a natural ecotechnology for wastewater treatment. Constructed wetland system is a treatment system, while it utilizes intertine relationship among water, plants, soils, microorganism and atmosphere in natural environment, and applies natural physics, chemistry and biochemical actions to remove pollutions natural. In addition, the constructed wetland can also to increase the areas to attract more wild animals as their habits. In this study, we analyzed quality of Koping River Old Railroad Bridge constructed wetlands to understand the remove efficiencies for different pollutions. The analytical results showed that A system of the constructed wetlands because some other sewage of A system flowed into the system. However, the treatment system were still better than those in B system. The average removal efficiencies of BOD5 ,COD ,NH3-N ,TP in A system equal to 81.93¢H,50.98¢H,74.89¢H,46,70¢H,respectively. However the average removal efficiencies of SS and Chlorophyll-a were increased for both A and B systems, which might because algae can grow vigorously in summer. Resulting in an increase for both Chlorophyll-a and SS. Besides, in autumn the litter effect of wetland plants might cause the concentrations of nutrients increased. In addition, in this study we also utilized emergy analysis to evaluate the economical values while comparing with a sewage treatment plant. The analytical results showed that the constructed wetlands could remove more pollutants than of the sewage treatment plant. However, the constructed wetland system could still increase the biodiversity. If they could reach steady treatment efficiencies under proper operation and maintenance. It is concluded that the constructed wetland system can provide advantages in both ecology and economics systems.
162

A New Combinatorial Strategy to Black-box Testing with Constraints

Tsai, Tsung-Han 23 July 2007 (has links)
In recent year, a lot of scholar try to generate test sets for combinatorial strategy automatically. But these algorithms based on combinatorial strategy don¡¦t consider conflicts of input parameter model. A conflict exists when the result of combining two or more values of different parameter dose not make sense. Thus, invalid sub-combinations may be included in test cases in the test suite, and these are useless to us. Besides, these algorithms all directly generate all test cases once, in other words, it is unable to utilize test cases generated at present to feedback and revise the algorithm, so it is easy to generate useless combinations. So, this paper proposes new test generation algorithm for combinatorial testing based on constraint satisfaction problem(CSP) to solve problem which invalid sub-combinations may be included in test cases, and we can add constraints flexibly during generating test cases to avoid generate useless or repeated combinations. The experimental result indicate that our algorithm perform well, with respect to the amount of time required for test generation, otherwise, we can generate conflict-free test cases directly.
163

Black Box Groups And Related Group Theoretic Constructions

Yalcinkaya, Sukru 01 July 2007 (has links) (PDF)
The present thesis aims to develop an analogy between the methods for recognizing a black box group and the classification of the finite simple groups. We propose a uniform approach for recognizing simple groups of Lie type which can be viewed as the computational version of the classification of the finite simple groups. Similar to the inductive argument on centralizers of involutions which plays a crucial role in the classification project, our approach is based on a recursive construction of the centralizers of involutions in black box groups. We present an algorithm which constructs a long root SL_2(q)-subgroup in a finite simple group of Lie type of odd characteristic $p$ extended possibly by a p-group. Following this construction, we take the Aschbacher&#039 / s ``Classical Involution Theorem&#039 / &#039 / as a model in the final recognition algorithm and we propose an algorithm which constructs all root SL_2(q)-subgroups corresponding to the nodes in the extended Dynkin diagram, that is, our approach is the construction of the the extended Curtis - Phan - Tits presentation of the finite simple groups of Lie type of odd characteristic which further yields the construction of all subsystem subgroups which can be read from the extended Dynkin diagram. In this thesis, we present this algorithm for the groups PSL_n(q) and PSU_n(q). We also present an algorithm which determines whether the p-core (or ``unipotent radical&#039 / &#039 / ) O_p(G) of a black box group G is trivial or not where G/O_p(G) is a finite simple classical group of Lie type of odd characteristic p answering a well-known question of Babai and Shalev. The algorithms presented in this thesis have been implemented extensively in the computer algebra system GAP.
164

Constant Speed Mechanism of Planetary Gear Train

Lin, Feng-Tien 12 September 2007 (has links)
In current years, searching for substitute energy such as the wind and ocean power of renewable energy is an important subject due to the petroleum shortage. The gear box is the key mechanism in the system of wind and ocean power. Moreover, the main function of the system is to generate electricity by speeding up the rotative velocity. However, the power of environment changes momentarily and makes the turbine a variable input. In order to improve the efficiency of generating electricity, it should get the constant input to keep the high quality of generating electricity. First of all, the study focuses on the gear box and synthesizes a constant speed mechanism of planetary gear train which degrees of freedom is two. In the mechanism, inputs are the variable speed turbine and a constant speed motor. When they input the mechanism, a constant speed output will be made to supply the generator. Secondly, it is necessary to set up the real object of the constant speed mechanism of planetary gear train. Finally, observing the real condition from the experiment to prove the theory is correct.
165

Study on MOBILE01 Website 3C Products ¡§Open Box Experience¡¨ Sharing Phenomenon

Ko, Kuang-Lin 20 August 2009 (has links)
This study uses Business Next magazine 2008 number one rating 3C product discussion group website Mobile01¡¦s ¡§open box experience¡¨ professional writers as study objects. The purpose of this study is to explore ¡§open box experience¡¨ sharing phenomenon and to understand writers¡¦ motivation and feedback in order to analyze the website management implication on this phenomenon. This study is based on soial cognitive theory, explores each dimension based on social cognitive theory and related items. The structure of this study includes people (capacity, attainment, enjoyment, positive feedback outcome expectation), environment (source of the product, exchange, feedback), behavior (the process of open box experience publication, reactions to feedback). This study adapts case study method. Researcher explored related journals, observed study object website. Based on the basic question categorization structure to construct interview questions, invited ¡§open box experience¡¨ experts and conducted open-ended expert in-depth interview. After each interview, the interview contents were typed into transcription. The transcription and the website data were used to describe ¡§open box experience¡¨ sharing phenomenon. Then the theme words which are related to the study were extracted from the transcription and became this study¡¦s basic elements. There are 264 themes extracted, coded and categorized in order to focus on the question. Finally, there are 252 effective themes selected and analyzed. Based on the major study findings, there are two conclusions: 1. The motivation of ¡§open box experience¡¨ writing is based on people¡¦s capacity, attainment and enjoyment. It also resulted by positive feedback outcome expectation by ¡§self purchase¡¨ or product source provided by online environment as well as exchange and feedback. 2. Negative feedback can result in keeping ¡§open box experience¡¨ writers from sharing and cause the lost of information for websites. Based on the above conclusions, this study provides suggestions to website owners, administrators, product vendors, ¡§open box experience¡¨ writers and readers. The suggestions can be used as references for website owners, administrators, product vendors when they are forming management strategies.
166

A Flexible Combinatorial Strategy based on Constraint Statisfaction Problem

Li, Cheng-Hsuan 23 August 2009 (has links)
In recent year the research field of the combinatorial testing, which can roughlybe divided into two kinds including pair-wise coverage and multi-wise coverage. a lot of scholar try to use various strategies to generate test data automatically. In order to weight the generated test set, the generated test data must satisfy certain criterion. But these combinatorial strategy neglected the flexibility of using on the practice. Considering software testing from the practice, which often be restricted by the cost. For this reason, how to obtaint the greatest testing benefits under the limited cost must be considered on the parctice. But in the extant combinatorial strategy, there is no flexible use. In other words, we must testing test set totally. Therefore, there is very great restriction to exist on using the test data generated by the extant combinatorial strategy on the practice. So, this paper proposes a flexible combinatorial strategy based on CSP, which allow users to do the most valid testing under the limited cost, which also allow users join the constraints that needs at any time during the testing process, revise the test data that we produced dynamically. The experimental result indicate that our method perform well, it can avoid including the test data whether some users think the interests less or unnecessarier, in order to achive the greatest testing beneifts.Further, we can achive the goal of reducing the quantity of testing data.
167

Behavior of stiffened compression flanges of trapezoidal box girder bridges

Herman, Reagan Sentelle. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.
168

Local and global investigations into DEAD-box protein function

Potratz, Jeffrey Philip 13 November 2013 (has links)
Numerous essential cellular processes, such as gene regulation and tRNA processing, are carried out by structured RNAs. While in vitro most RNAs become kinetically trapped in non-functional misfolded states that render them inactive on a biologically-relevant time scale, RNAs folding in vivo do not share this same outcome. RNAs do indeed misfold in the cell; however, chaperone proteins promote escape from these non-native states and foster folding to functional conformations. DEAD-box proteins are ATP-dependent RNA chaperone proteins that function by disrupting structure, which can facilitate structural conversions. Here, studies with both local and global focuses are used to uncover mechanistic features of DEAD-box proteins CYT-19 and Mss116p. Both of these proteins are general RNA chaperones as they each have the ability to facilitate proper folding of multiple structured RNAs. The first study probes how DEAD-box proteins interact with a simple duplex substrate. Separating the strands of a duplex is an ATP-dependent process and is central to structural disruption by DEAD-box proteins. Here, how ATP is utilized during duplex separation is monitored by comparing ATP hydrolysis rates with strand separation rates. Results indicate that one ATP molecule is sufficient for complete separation of a 6-11 base pair RNA duplex. Under some conditions, ATP binding in the absence of hydrolysis is sufficient for duplex separation. Next, focus is shifted to a more global perspective as the function of Mss116p is probed in the folding of a cognate group II intron substrate, aI5[gamma], under near-physiological conditions. Three catalytically-active constructs of aI5[gamma] are used and catalysis serves as a proxy for folding. Folding of all constructs is promoted by the presence of Mss116p and ATP. In vitro and in vivo results indicate that a local unfolding event is promoted by Mss116p, stimulating formation of the native state. Lastly, orthogonal methods that probe physical features of RNA are used to provide insight into the structural intermediates with which Mss116p acts. / text
169

Fossils, phylogeny, and anatomical regions : insights exemplified through turtles

Burroughs, Robert Wayne 15 November 2013 (has links)
There are more than 300 species of extant turtles, the majority of which belong to the Testudinoidea. Here I describe a new box turtle from the Eocene-Oligocene boundary of west Texas. This specimen impacts the phylogeny of Testudinoid turtles by pulling the divergence of extant Testudinoid turtles back in time approximately 25 million years. This results in a need to refocus on paleontological research of Testudinoid turtles into the late Paleogene and early Neogene to identify fossil localities and specimens that can help further elucidate the evolution of the group. New work on the fossil record of turtles also requires a re-evaluation of methods used for identifying and evaluating the evolutionary history of turtles as a group. An implicit assumption over the last 150 years of turtle paleontology was that both turtle shells and turtle heads reveal congruent and complimentary evolutionary relationships. This assumption was never adequately tested. I utilized a series of methods to evaluate the congruency of phylogenetic hypotheses using disparate anatomical regions. Using a dataset of extant Emydid turtles, I evaluated whether turtle shells and turtle heads provided congruent and complimentary phylogenetic hypotheses. My methods employed parsimony-based reconstruction, maximum-likelihood-based reconstruction, and Bayesian-based reconstruction, including Bayesian-partition analyses. My conclusions are that heads and shells do not provide fully congruent topologies, and that in many cases there is a loss of phylogenetic resolution when only turtle sklls are used to generate phylogenies. The implication is that a focus on a robust and complete dataset of anatomical features will provide the best basis for further investigation of fossils. My work also provides a framework for dataset exploration by providing a method to identify the most robust phylogenetic signal found within a dataset. This framework will allow non-turtle paleontologists and systematists the ability to further investigate their own datasets and develop robust hypotheses of evolutionary relationships across the diversity of the tree of Life. / text
170

Insights into the regulation of the DEAH-box helicase Prp43p through its interactions with three G-patch proteins

Hennigan, Jennifer Ann 11 July 2014 (has links)
The RNA helicase Prp43p is one of the few members of the DEAH-box helicase family that is known to operate in more than one cellular process in Saccharomyces cerevisiae. With roles in ribosome biogenesis and pre-mRNA splicing, Prp43p may be important in maintaining a communication conduit between these two pathways. Our studies provide insights into how Prp43p function is regulated through the use of three cofactors, Ntr1p, Pfa1p, and Gno1p, all of which interact with Prp43p at different steps of pre-mRNA splicing or ribosome biogenesis. Each cofactor contains a unique G-patch domain and our data show that they associate with Prp43p in a mutually exclusive manner. A strong growth defect and RNA processing phenotypes are seen upon overexpression of Pfa1p due to the dominance of Pfa1p interaction with Prp43p. Moreover, excess Pfa1p precludes Prp43p from interacting with either 35S pre-rRNA or U6 snRNA, indicating this one cofactor can negatively regulate Prp43p recruitment into ribosome biogenesis and pre-mRNA splicing pathways, respectively. We have determined that Ntr1p and Gno1p are able to compete with one another for Prp43p occupancy. Similar to Ntr1p, we show that the G-patch domain of Gno1p contributes to its association with Prp43p. To further understand pathway specificity of Prp43p, we characterized conditional prp43 alleles with mutations C-terminal to the conserved RecA domains of Prp43p. These novel alleles affect pre-mRNA splicing and ribosome biogenesis, though none are mutually exclusive. Multiple prp43 alleles are deficient in tri-snRNP formation, a previously uncharacterized phenotype in prp43 mutants. The majority of our prp43 mutants display varying rRNA defects, with some alleles impacting ribosome biogenesis more severely or moderately than known prp43 ATPase mutants. To correlate the processing defects seen in each allele, we have determined the extent of association of the mutants with each G-patch protein. Altogether, our data support a working model for Prp43p in which its substrate specificity, activation, and cellular distribution is coordinated through the efforts of the three G-patch proteins in yeast and sheds light on potential mechanisms of general DExH/D helicase function and regulation. / text

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