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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.
271

Some Aspects on Robust Stability of Uncertain Linear Singularly Perturbed Systems with Multiple Time Delays

Chen, Ching-Fa 21 June 2002 (has links)
In this dissertation, the robust stability of uncertain continuous and discrete singularly perturbed systems with multiple time delays is investigated. Firstly, the asymptotic stability for a class of linear continuous singularly perturbed systems with multiple time delays is investigated. A simple estimate of an upper bound of singular perturbation parameter is proposed such that the original system is asymptotically stable for any . Moreover, a delay-dependent criterion, but -independent, is proposed to guarantee the asymptotic stability of the original system. Secondly, we consider the robust stability problem of uncertain continuous singularly perturbed systems with multiple time delays. Two delay-dependent criteria are proposed to guarantee the robust stability of a class of uncertain continuous multiple time-delay singularly perturbed systems subject to unstructured perturbations. Thirdly, the robust D-stability of nominally stable discrete uncertain systems with multiple time delays is considered. Finally, the robust stability of nominally stable uncertain discrete singularly perturbed systems with multiple time delays subject to unstructured and structured perturbations is investigated. Some criteria, delay-dependent or delay-independent, will be proposed to guarantee the robust stability of the uncertain discrete multiple time-delay singularly perturbed systems. The improvements of our results over those in recent literature are also illustrated if the comparisons are possible. Some numerical examples will also be provided to illustrate our main results.
272

Rebuilding Afghanistan : counterinsurgency and reconstruction in Operation Enduring Freedom /

Armstrong, Bradley J. January 2003 (has links) (PDF)
Thesis (M.S. in Defense Analysis)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Hy S. Rothstein, Kalev K. Sepp. Includes bibliographical references (p. 162-175). Also available online.
273

State policy and urban politics in Hong Kong: a mode of production analysis

Ho, Bo-shan., 何寶山. January 1990 (has links)
published_or_final_version / Urban Studies / Master / Master of Social Sciences
274

The stabilities of RNA and DNA structural elements

Zhu, Jian 05 1900 (has links)
No description available.
275

State policy and urban politics in Hong Kong : a mode of production analysis /

Ho, Bo-shan. January 1990 (has links)
Thesis (M. Soc. Sc.)--University of Hong Kong, 1990.
276

The degradation of drugs in formaldehyde

James, Devona Gwen, January 1999 (has links)
Thesis (M.S.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains xvi, 100 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 98-99).
277

State policy and urban politics in Hong Kong a mode of production analysis /

Ho, Bo-shan. January 1990 (has links)
Thesis (M.Soc.Sc.)--University of Hong Kong, 1990. / Also available in print.
278

Self-esteem, motivation, and self-enhancement presentation on WeChat

Qiu, Xiao 23 March 2018 (has links)
The purpose of the present study was to analyze whether self-esteem stability moderated the association between self-esteem level and the forms of self-enhancement strategies. Previous research has found that self-esteem level can predict the forms of self-enhancement, whereas the advances in the conceptualization of self-esteem recommend that the self-esteem stability is another essential variable in terms of analyzing the relationship between self-esteem and self-enhancement. Depending on the relevant researches on use and gratification theory, which indicate that people use social media for self-enhancement and fulfilling their inner needs. This research focused on examining the forms of individual’s self-enhance on WeChat Circle of Friends (COF) and how it influenced by the interaction between self-esteem level and self-esteem stability by analyzing 305 participants in China. The results of the study show that both self-esteem level and stability was positively correlated with direct self-enhancement, but negatively correlated with indirect self-enhancement. Furthermore, the findings also show that self-esteem stability moderated the association between self-esteem level and direct self-enhancement such that individuals with stable high self-esteem reported higher levels of frequency in direct self-enhancement. However, the findings also revealed the self-esteem stability failed to moderate the association between self-esteem level and indirect self-enhancement presentation. These results suggest that self-esteem level and self-esteem stability will interact to impact the forms of self-enhancement. The importance of considering both stability and level of self-esteem in analyses of self-enhancement presentation on social media is discussed.
279

An experimental study of instability in square plates twisted by corner forces

Williams, Gordon Colin January 1988 (has links)
An experimental study is presented on the non-linear twisting of plates with free edges, through the application of self-equilibrating corner loads. A simple apparatus was designed and various sizes of plates were twisted while measuring the surface strains on both sides at the centre. Initial difficulty was encountered due to unwanted deflection of the plate under its own weight. The Rayleigh-Ritz method is used to determine an analytical relationship between midsurface strains and curvatures in the pre- and post-bifurcation regions of twisting. In both the experimental and analytical results, the midsurface strains are found to vary linearly with the Gaussian curvature. Non-dimensional groups are identified which collapse the experimental load-strain, load-curvature and midsurface strain-Gaussian curvature relationships. These non-dimensional groups collapse the results in both the linear and non-linear regions. The curvature at the point of bifurcation is identified as a function of plate dimensional parameters. Also shown are the expressions for critical surface strain and corner load at which bifurcation occurs. The experimental load-curvature relationship and point of bifurcation are compared with analytical results found in the literature. A large discrepancy in the literature is resolved for the theoretical point of bifurcation. The present results form a basis for verification of future analytical results, and are important in the measurement of constitutive relationships using the twisted plate test. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate
280

Stanovení komplexačních konstant metodou částečného plnění a analýzou průtokem způsobené disperze a jejich srovnání s hodnotami stanovenými metodou afinitní kapilární elektroforézy / Determination of complexation constants by partial Filling method and Flow Induced Dispersion Analysis and their comparison with values determined by Affinity Capillary Electrophoresis

Ansorge, Martin January 2016 (has links)
Partial Filling method (PF) and Flow Induced Dispersion Analysis (FIDA) were used for the determination of stability constants of model system of four profens (R-Flurbiprofen, S-Ibuprofen, S-Ketoprofen and S-Naproxen) complexing with β-cyclodextrin. When using PF method, only a part of capillary is filled with the selector and thus the analyte must migrate through the zone of selector first and then through the neat BGE (it has different mobilities in both zones). Dependency of the differences in migation time on the length of the selector zone is then studied. When FIDA is used, the analyte in pushed through the capillary by external pressure and dependency of the rate of peak dispersion of the analyte on the concentration of selector in capillary is observed. Moreover, PF experiments were theoretically studied by Simul 5 Complex computing programme. Values of stability constants obtained by both methods were compared with values obtained by frequently used Affinity Capillary electrophoresis (ACE) method. The comparison of stability constants values determined by PF method and FIDA shows that both investigated methods grants results comparable with those obtained by the ACE.

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