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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.
211

Carnap and Quine on Analyticity

Moosavi Karimi, Seyed Masoud January 2012 (has links)
This dissertation examines the Carnap-Quine debate on analyticity with the objective of identifying exactly what is at stake. Close scrutiny of Quine’s criticism of the definitions of analyticity reveals that most of his objections are convincing only if they are considered in relation to the definitions of analyticity in natural language. Carnap, however, defines analyticity in artificial languages. The dissertation also shows that Carnap can meet the objections to his definitions by using a perspective based within his own philosophy. After examining the presumptions of each party to the debate, the dissertation concludes that the disagreement between Carnap and Quine on the notion of analyticity is rooted in their different approaches to empiricism and that there is nothing said by either philosopher which proves that one approach has ultimate advantages over the other. It is thus impossible to identify a winner in the Carnap-Quine debate on analyticity. The process of arriving at this conclusion starts with a discussion in the first three chapters of Carnap’s philosophy followed by a critical and detailed discussion of his syntactical and semantical definitions of analyticity and the advantages and disadvantages of each. Chapter Four examines Quine’s objections to Carnap’s definitions of essential predication and shows that his objections do not undermine Carnap’s definitions of this notion in artificial languages. It also shows how vital providing a proper definition of essential predication in natural language is for Carnap’s philosophy and examines whether or not he is able to do so. Chapter Five analyzes Quine’s objections to Carnap’s definitions of logical truth and demonstrates that Carnap is able to respond to all of them when the discussion is situated within his philosophical system. Again, Quine’s objections to definitions of logical truth are meaningful only if they are considered in relation to natural language, which is not Carnap’s concern. The dissertation concludes by showing that both Carnap and Quine arrived at their conclusions with respect to the nature of logical sentences, based not on the arguments in their debate on analyticity, but on their philosophical considerations regarding the principle of empiricism: for Carnap, logical sentences are out of the realm of knowledge and independent of matters of fact whereas, for Quine, these are as empirical as other sentences. Nothing either says in their debate can convince the other to accept a different viewpoint.
212

Synthetic Studies Toward B-Alkylthiolanthionines

Kim, Hwa-Ok 01 May 1987 (has links)
Synthetic routes toward a B-alkylthiolanthionine derivative, as found in the quinomycin depsipeptide antibiotics, have been studied through a sequence involving as the key intermediates and steps (a) (S) - Z-[(benzyloxycarbonyl)amino]-3,3-dimethoxy-l-propanol (2), prepared from N-benzyloxycarbonyl-L-serine in 3 or 4 steps, (b) N-benzyloxycarbonyl- 0 - tetrahydropyranyl-B,B-(ethylsulfinylethylthio)-alaninol (4a), converted from 2, and (c) attempted Lewis acid catalyzed replacement of alkylsulfinyl function by thiol moiety of cysteine, which gave undesired products. Stability of protecting groups used in this study, which are N,0-isopropylidenyl and tetrahydropyranyl functions in N-protected-L-serinol 20 or 26, under acidic conditions was found to play an important role in determining the optical purity obtained in 2. Jone's oxidation and methylation of 2 led to the formation of N-benzyloxycarbonyl-B,B-(dimethoxy)alanine methyl ester (3) in low yield. Swern oxidation or Moffat oxidation of Z-L-Ser-Val-OMe dipeptide (5), which was expected to be converted to aldehyde 34, were carried out with unsuccessful results. Swern oxidation was applied to various N-protected amino alcohols derived from a-amino acids to give the corresponding aldehydes with excellent yields and optical purities.
213

Synthetic Studies Toward Key Portions of the Didemnins

Kim, Ok-Soon 01 May 1988 (has links)
Three different synthetic approaches toward N-[(2SR, 4S)-4-hydroxy-2,5-dimethyl-3-oxohexanoyl]-Lleucine methyl esters were carried out by use of i) aldol condensation and amination ii) Claisen condensation and soft acid coupling reaction iii) methylation of Hia-Leu derivative in relatively high yields. (4S)-3-[(2SR,4S)-2,5-Dimethyl-1,3-dioxo-4-(methoxyethoxymethyloxy) hexyl]-4-(1-methylethyl)-2-oxazolidinone was prepared by the reaction of aldol condensation of lithium enolate of Evans' chiral auxilary in 80 : 20 diastereomeric ratio. A new method for the synthesis of (4S)-4-(t-butoxycarbonyl)amino-5-methyl-3- oxoheptanoic acid ethyl ester (Statone) was developed by the reaction of Boc-leucine with Meldrum's acid, followed by transesterification and decarboxylation in modest yield. Other a-amino acids also were applied to this methodology in successful yields. Attempts to prepare the linear molecule, containing Statone-(4S)-5-methyl- 3-oxohexanoyl- Leu-OCpa, an analogue of Epista-Hip-Leu, was not successful.
214

Thermal and kinetic characterization of thermosetting resins diving cure

Sourour, Sami January 1978 (has links)
No description available.
215

Novel synthetic routes to organosilicon species

Yeh, Li-Tain January 1991 (has links)
No description available.
216

Assessing the Economic Feasibility of Synthetic Natural Gas Under Conditions of Uncertainty

Iranmanesh, Mohammad M. 01 October 1981 (has links) (PDF)
The science of synthetic fuel production began in the seventeenth century. However, large-scale production of synthetic fuels started in the early 1900's and, for several decades, gas manufactured from coal significantly contributed to the U.S. economy. The production of synthetic fuels declined due to increases in the price of coal and discoveries of predominantly methane natural gas. Today, an extensive network of pipelines is used to transmit and distribute natural gas for industrial and residential applications. The decline of natural gas reserves in the United States, in conjunction with the availability of very large coal reserves, has provided the incentive for development of coal gasification plants. Synthetic fuels are expected to contribute significantly to the supply of energy before the end of this century, and coal will be the primary source for production of these fuels. By many accounts, difficulties in raising the high amount of initial capital and future uncertainties with regard to fuel and operating costs have made development of synthetic fuels economically infeasible. However, as the prices of oil and natural gas increase, synthetic fuels production becomes a more attractive alternative. The purpose of this study is to evaluate the economics of synthetic natural gas with the current state of technology and to determine its future role as prices of oil and gas increase. In this report, a general methodology of production of synthetic natural gas is explained. For the economic analysis, the Lurgi Model was selected because it has been the most common model used for commercial production of high BTU gases. An extensive analytical model is described in which inflated capital, fuel, and operating and maintenance costs were accounted for and the equivalent annual cost of cash flows over the project life was calculated. The risk analysis was accomplished by applying Monte Carlo techniques through a simulation model which handles risks associated with various input parameters. SLAM, a FORTRAN-based language, was selected as the simulation language. Based on the results, all the cost elements were evaluated and the sensitivity of the total cost to each element was examined. This study was extended to the calculation of costs associated with he generation of electricity by burning synthetic natural gas. The results were then compared to the respective costs related to oil-burning power plants. The results show that high cost of synthetic high BTU gas makes it difficult to compete with natural gas at current prices. Coal feed stocks represent a major portion of the total cost of synthetic gases. The cost of capital, which is a critical factor at the developing stage, constitutes a relatively small portion of the total cost over the plant life. A similar observation was made for operating and maintenance costs. However, the future regulations regarding pollution control could have a strong impact on this portion of the cost. For power generations, oil was found to be far more economical than using synthetic natural gas. The computer simulation also revealed that the total cost of each alternative is very sensitive to this fuel cost. The conclusion of this study points to the fuel costs as the dominant factor in the choice of fuel alternatives in the future.
217

A Framework for Data Quality for Synthetic Information

Gupta, Ragini 24 July 2014 (has links)
Data quality has been an area of increasing interest for researchers in recent years due to the rapid emergence of 'big data' processes and applications. In this work, the data quality problem is viewed from the standpoint of synthetic information. Based on the structure and complexity of synthetic data, a need to have a data quality framework specific to it was realized. This thesis presents this framework along with implementation details and results of a large synthetic dataset to which the developed testing framework is applied. A formal conceptual framework was designed for assessing data quality of synthetic information. This framework involves developing analytical methods and software for assessing data quality for synthetic information. It includes dimensions of data quality that check the inherent properties of the data as well as evaluate it in the context of its use. The framework developed here is a software framework which is designed considering software design techniques like scalability, generality, integrability and modularity. A data abstraction layer has been introduced between the synthetic data and the tests. This abstraction layer has multiple benefits over direct access of the data by the tests. It decouples the tests from the data so that the details of storage and implementation are kept hidden from the user. We have implemented data quality measures for several quality dimensions: accuracy and precision, reliability, completeness, consistency, and validity. The particular tests and quality measures implemented span a range from low-level syntactic checks to high-level semantic quality measures. In each case, in addition to the results of the quality measure itself, we also present results on the computational performance (scalability) of the measure. / Master of Science
218

Entrainment of Bacterial Synthetic Oscillators using Proteolytic Queueing and Aperiodic Signaling

Hochendoner, Philip Louis 12 December 2015 (has links)
The bulk of this thesis considers how biological rhythms (oscillators) can be made to synchronize their rhythms by virtue of coupling to an external signal. Such externally controlled synchronization, known as entrainment, is explored using a synthetic biology approach in E.~coli, where I have used rationally designed gene circuits as an experimental model. Two novel modes of entrainment are explored: entrainment by competition between components for degradation, and entrainment by a noisy (aperiodic) stimulus. Both of these modes of entrainment can be shown to strongly synchronize ensembles of synthetic gene oscillators, and thus, these modes of entrainment may be important to understand the appearance of synchrony in natural systems. In addition to the study of entrainment, this thesis contains a general background of relevant material, contributions to the biophysics of multisite proteases, and updated protocols for experimental procedures in microfluidics and microscopy. / Ph. D.
219

Implementing Lexical And Creative Intentionality In Synthetic Personality

Vick, Erik 01 January 2005 (has links)
Creating engaging, interactive, and immersive synthetic characters is a difficult task and evaluating the success of a synthetic character is often even more difficult. The later problem is solved by extending Turing's Imitation Game thusly: computational construct should be evaluated based on the criteria of how well the character can mimic a human. In order to accomplish a successful evaluation of the proposed metric, synthetic characters must be consistently believable and capable of role-appropriate emotional expression. The author believes traditional synthetic characters must be improved to meet this goal. For a synthetic character to be believable, human users must be able to perceive a link between the mental state of the character and its behaviors. That is to say, synthetic characters must possess intentionality. In addition to intentionality, the mental state of the character must be human-like in order to provide an adequate frame of reference for the human users' internal simulations, to wit, the character's mental state must be comprised of a synthetic model of personality, of personality dynamics, and of cognition, each of which must be psychologically valid and of sufficient fidelity for the type of character represented. The author proposes that synthetic characters possessing these three models are more accurately described as synthetic personalities. The author proposes and implements computational models of personality, personality dynamics, and cognition in order to evaluate the psychological veracity of these models and computational equivalence between the models and the implementation as a first step in the process of creating believable synthetic personalities.
220

Opinions of two groups of homemakers concerning the values possessed by clothing fabrics made from various fibers

Hoffman, Fern Maxine January 2011 (has links)
Digitized by Kansas State University Libraries

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