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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.
581

The integration of CAD/CAM with virtual machining simulation and cost estimation

Johnson, Chad A. January 1997 (has links)
No description available.
582

Hydrogen exchange reactions in flow systems

Hsieh, Hsiou-Ching. January 1978 (has links)
Call number: LD2668 .T4 1978 H75 / Master of Science
583

AN IMPLEMENTATION OF A COMPLETE XML SYSTEM FOR TELEMETRY SYSTEM CONFIGURATION

Portnoy, Michael 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Creating a generic, multi-vendor data exchange system for transmitting telemetry configurations between various systems is a daunting task. To date many different systems have been proposed including relational databases (RDBMS), TMATS, and several different XML schemas. Although many of these systems have been implemented, a complete, flexible solution has not been developed. This paper describes an implementation that is currently in use for exporting and importing a complete telemetry system via XML. Using this system, an engineer can import an entire telemetry configuration, a partial telemetry configuration, or even just a single measurement (parameter). As a result, the gap between user database systems and the airborne instrumentation vendor’s configuration software (IVCS) is seamlessly bridged. This provides many benefits including: the ability to rapidly change configurations, data entry error avoidance, version control, the protection of sensitive information, and configuration reusability. This system allows for the configuration of all aspects of the telemetry setup including data acquisition hardware, transmitters, ground stations, and recorders. In addition, the recorder settings and the definition of the data that are to be recorded are coupled and linked to the rest of the telemetry configuration, which facilitates future data recovery.
584

Zeolite Formation and Base Exchange Reactions in Soils

Burgess, P. S., McGeorge, W. T. 01 May 1927 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
585

The Action of Aluminum Ferrous and ferric Iron, and Manganese in Base Exchange Reactions

Magistad, O. C. 01 February 1928 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
586

Base Exchange in Orthoclase

Breazeale, J. F., Magistad, O. C. 01 August 1928 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
587

Design and evaluate a fair exchange protocol based on online trusted third party (TTP)

Alotaibi, Abdullah S. January 2012 (has links)
One of the most crucial factors that e-commerce protocols should address is a fair exchange. In this research, an advanced method of cryptography coupled with the pay per use technique is used. A new electronic commerce protocol for the exchange of commodities is introduced. The proposed new protocol guarantees both features while addressing the main drawbacks associated with other related protocols. The new suggested e-commerce protocol is composed of two stages: pre-exchange and exchange stages. When the suggested new protocol is analysed with scrupulous protocol analysis, it attains fair exchange and a secure method of payment. The suggested new e-commerce protocol is more efficient than other related existing protocols. In this research “protocol prototype” and “model checking” is used for the purpose of authentication. The protocol prototype verifies that the suggested new protocol is executable when it's used in a real context. By experimental designs, this research shows the length of asymmetric keys as the biggest element that affects the efficiency of the protocol. When model-checking is applied in this protocol, the outcome indicates that the suggested protocol achieves the required features of fairness. Protocol extensions give those involved in the protocol the capacity to be resilient to failure. By using three methods of authentication, this research confirms that the new proposed protocol is well formulated. The work reported in this thesis first study the existing fair exchange protocols that solve the fairness problem. Then, propose more efficient protocol to solve the fairness problem. The original idea in this thesis is to reduce the communication overheads, risks and solve the bottleneck problems in the protocols that involve an online TTP.
588

Essays in exchange rates and international finance

Menla Ali, Faek January 2014 (has links)
This thesis is based on four essays in exchange rates and international finance. The first essay, examined in the second chapter, considers the long-run performance of the flexible-price monetary model as well as the real interest differential monetary model to explain the dollar–yen exchange rate during a period of high international capital mobility. We apply the Johansen methodology to quarterly data over the period 1980:01–2009:04 and show that the inadequacy of the two monetary models is due to the breakdown of their underlying building-blocks, money demand stability and purchasing power parity. In particular, modifying the monetary models by adjusting them for real stock prices to capture the stability of money demands on one hand and also for real economic variables such as productivity differential, relative government spending, and real oil price to explain the persistence in the real exchange rate on the other provide long-run relationships that appear consistent with the monetary models. Our findings of long-run weak exogeneity tests also emphasise the importance of the extended models employed here. The second essay, examined in the third chapter, is on the nature of the linkages between stock market prices and exchange rates in six advanced economies, namely the US, the UK, Canada, Japan, the euro area, and Switzerland, using data on the banking crisis between 2007 and 2010. Bivariate GARCH-BEKK models are estimated to produce evidence of unidirectional Granger causality from stock returns to exchange rate changes in the US and the UK, in the opposite direction in Canada, and of bidirectional causality in the euro area and Switzerland. Furthermore, causality-in-variance from stock returns to exchange rate changes is found in Japan and in the opposite direction in the euro area and Switzerland, whilst there is evidence of bidirectional causality-in-variance in the US and Canada. These findings imply limited opportunities for investors to diversify their assets during this period. The third essay, examined in the fourth chapter, considers the impact of net bond and net equity portfolio flows on exchange rate changes. Two-state Markov-switching models are estimated for the exchange rate of the US vis-a-vis Canada, the euro area, Japan and the UK. Our results suggest that the relationship between net portfolio flows and exchange rate changes is nonlinear for all cases considered, except that of the US dollar against the Canadian dollar. The fourth essay, examined in the fifth chapter, considers the impact of exchange rate uncertainty on different components of net portfolio flows, namely net equity and net bond flows, as well as the dynamic linkages between exchange rate volatility and the variability of these two types of flows. Specifically, a bivariate GARCH-BEKK-in mean model is estimated using bilateral data for the US vis-à-vis Australia, the UK, Japan, Canada, the euro area, and Sweden over the period 1988:01-2011:12. The results indicate that the effect of exchange rate uncertainty on net equity flows is negative in the euro area, the UK and Sweden, and positive in Australia, whilst two countries (Canada and Japan) showed insignificant responses. With regard to the impact of uncertainty on net bond flows, it is shown to be negative in all countries, except Canada (where it is positive). Under the assumption of risk aversion, this suggests that exchange rate uncertainty induces investors, especially those of the counterpart countries to the US, to reduce their financing activities to maximise returns and minimise exposure to uncertainty. This evidence is strong for the UK, the euro area and Sweden as opposed to Canada, Australia and Japan. Furthermore, since exchange rate volatility and the variability of flows are interlinked, exchange rate or credit controls on these flows can be used to pursue economic and financial stability.
589

Two-phase local heat transfer correlations for non-ozone depleting refrigerant-oil mixtures

Boissieux, Xavier January 1998 (has links)
This thesis describes the work undertaken over a 3 year period under a Department of the Environment, Transport and the Regions (DETR) Partners in Technology programme in collaboration with four industrial partners. The aim of the work was to investigate the two-phase flow heat transfer and fluid dynamic performance of the non-ozone depleting refrigerants and lubricating oil mixtures in a horizontal tube. A single tube test facility was designed and built to determine local heat transfer coefficients and overall pressure drop for evaporation and condensation. A circulating pump system pressurised through an accumulator charged with nitrogen was selected to enable accurate setting of the evaporation and condensation conditions. The system was validated using R22. Tests were undertaken for R404A, R407C, Isceon 59 with a Polyol-ester lubricating oil. The experimental data consist of two-phase local heat transfer coefficients and overall pressure drops inside a smooth copper tube. Numerous data were obtained for evaporation and condensation, and constituted a large database of two-phase heat transfer coefficients. The experimental results were compared with several existing correlations traditionally used in heat exchanger design, to assess their suitability with the new refrigerants. As a result of these comparisons offering a poor agreement, a model characterising the variation of the local heat transfer coefficient was developed. The evaporation model consists in a modification of the Kattan et al. model (1998a, b & c). The new model predicts the experimental results well, with a standard deviation of 6.1% for refrigerant R407C and Isceon 59. The effects of lubricating oils on two-phase flow heat transfer are also discussed qualitatively. This work provides a design tool when dealing with the non-ozone depleting refrigerants, and recommendations are made on the use of several correlations.
590

Public policy and business development in tourism, with particular reference to small firms

Thomas, Rhodri January 2015 (has links)
The integrative chapter of this thesis explains how the nominated papers, when combined, meet the University of Exeter’s assessment criteria for the award of PhD by Publication. It argues that a coherent contribution to knowledge emerges from the three strands of research discussed, namely: (i) examinations of research and innovation policy, notably via the work of tourism academics and the knowledge exchange practices of practitioners; (ii) investigations into the practices of small businesses in tourism, particularly in relation to their articulation with public policy at a local level; (iii) an assessment of the professionalization of tourism, via the conceptual lens of corporate professionalization. Collectively, these publications explain important aspects of business, notably small business, dynamics in tourism; my contribution has been to provide new conceptualisations of tourism organisations and explanations for their behaviour that advance existing academic accounts. The theoretical contributions made offer public policy-makers greater scope for developing interventions to more effectively influence business behaviour than at present. The chapter also reviews, briefly, the range of methods of enquiry used in my research and my philosophical position in relation to knowledge construction. Finally, the limitations of my work and my current research agenda are discussed.

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