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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

Decomposed network and heuristic approach for rail transport crew scheduling system

Chan, Cheuk-ho. January 1997 (has links)
Thesis (M.Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 91-95) Also available in print.
162

Shift rotation selected physiological and psychological effects : a research report submitted in partial fulfillment ... /

Pilon, Christine E. Zang, Laura M. January 1976 (has links)
Thesis (M.S.)--University of Michigan, 1976.
163

Analýza zaměstnanosti a důchodů obyvatel v ČR / Analysis of Employment and Income Population in the Czech Republic

ŠIKLOVÁ, Lucie January 2011 (has links)
The aim is to assessment the development of employment and income. Assess the dynamics and differentiation of net cash income of the population by region and sector of the economy. Employment is one of the key areas of concern not only the Czech Republic, but all Member States of the European Union. Employment policy is intended to promote employment and is one of the major areas of social policy. The incomes of the population significantly affects living standards, competitiveness and hence aggregate demand. For surveys of household income to apply various methods. Income inequality can be measured in different ways. The most popular methods include the Gini coefficient and Lorenz curve. The household is most popular statistical unit whose income is observed.
164

Problema restrito dos três corpos / Restrict three body problem

Fernando Pereira Micena 23 February 2007 (has links)
O problema de n?corpos é um dos problemas mais importantes em Sistemas Dinâmicos. Nós estudamos o modelo do problema dos três corpos restrito introduzido por Sitnikov. Nesse modelo os corpos primários tem a mesma massa e o terceiro corpo é de massa muito pequena com respeito aos corpos primários. Usando os métodos de Alekseev, nós mostramos a existência de uma ?ferradura de Smale?como um subsistema da dinâmica do terceiro corpo e concluímos ricas conseqüências probabilísticas. Nós também estudamos o problema pelo método de Melnikov / The n?body problem is one of the most important problems in dynamical systems. We study the model introduced by Sitnikov of restricted three body problem. In this model the primaries are of equal mass and the third body is very small with respect to the primaries. Using methods of Alekseev, we show the existence of ?Smale horseshoe?as a subsystem of the dynamic of the third body and conclude rich probabilistic consequences. We also study the same problem by Melnikov?s method
165

A competitividade das exportaÃÃes de castanha de caju e melÃo no Nordeste brasileiro: 1997-2013. / The competitiveness of exports of cashew nuts and melons in northeast Brazil: 1997-2013.

JanaÃna AraÃjo Barbosa 05 April 2016 (has links)
O desenvolvimento da fruticultura no Nordeste brasileiro enfrentou alguns desafios e limites nos Ãltimos anos. Contudo, devido ao avanÃo de novas tecnologias e pesquisas, conseguiu avanÃar em alguns aspectos, tornando favorÃvel o crescimento da produÃÃo de determinadas culturas, as quais sÃo beneficiadas pela crescente demanda internacional de commodities e pelo preÃo atrativo, proporcionando renda e emprego para os exportadores, produtores e trabalhadores envolvidos na atividade. Diante disso, este estudo tem como objetivo fundamental analisar o comportamento e as principais fontes de avanÃo ou retraÃÃo das exportaÃÃes da castanha de caju e do melÃo na regiÃo Nordeste, por meio de variÃveis comumente conhecidas como influenciadoras para as exportaÃÃes desses produtos, as quais sÃo: preÃo do produto em moeda internacional, taxa de cÃmbio, Ãrea colhida, rendimento mÃdio da produÃÃo e quantidade produzida pelos concorrentes internacionais. As informaÃÃes utilizadas na pesquisa foram retiradas do Sistema AliceWeb do MinistÃrio do Desenvolvimento, IndÃstria e ComÃrcio Exterior (MDIC), da ProduÃÃo AgrÃcola Municipal do Instituto Brasileiro de Geografia e EstatÃstica (IBGE) e do IpeaData. Para avaliar esses fatores influenciadores fez-se uso da metodologia Shift Share, com o uso de sÃries temporais cobrindo o perÃodo compreendido entre 1997 e 2013. A metodologia utilizada no trabalho à inovadora neste tipo de anÃlise e consiste na decomposiÃÃo do valor das exportaÃÃes destas duas commodities nos efeitos tidos como definidores dos avanÃos ou retrocessos do valor das exportaÃÃes nordestinas dos dois produtos. Os resultados encontrados na pesquisa mostraram que a regiÃo Nordeste està perdendo competitividade em relaÃÃo aos seus principais concorrentes (Vietnà e Ãndia) na produÃÃo e exportaÃÃo de castanha de caju, tanto no que concerne à expansÃo de Ãrea colhida como, principalmente, de rendimento relativo, numa evidÃncia de que a produÃÃo nordestina de castanha de caju avanÃa em descompasso tecnolÃgico em relaÃÃo aos seus dois principais concorrentes no mercado internacional. Considerando a produÃÃo e exportaÃÃo de melÃo pela regiÃo, as evidÃncias encontradas na pesquisa sugerem avanÃos da participaÃÃo nordestina no mercado internacional de melÃo, demonstrando uma maior competitividade frente à produÃÃo deste item nos principais concorrentes internacionais, que sÃo Espanha, Guatemala e Estados Unidos da AmÃrica. / The development of fruit production in Northeast Brazil faced some challenges and limits in recent years. However, due to the advancement of new technologies and research, managed to advance in some respects, making favorable growth in production of certain crops, which are benefited by the growing international demand for commodities and the attractive price, providing income and employment for exporters, farmers and workers involved in the activity. Thus, this study is essential to analyze the behavior and the main sources of progress or decline in exports of cashew nuts and melon in the Northeast, through commonly known variables as influencers for exports of these products, which are: price of the product in international currency exchange rates, harvested area, average yield in production and the quantity produced by international competitors. The information used in the research were taken from AliceWeb the Ministry of Development System, Industry and Foreign Trade (MDIC), the Municipal Agricultural Production of the Brazilian Institute of Geography and Statistics (IBGE) and IpeaData. To evaluate these influencing factors was made using the Shift Share methodology, using time series covering the period 1997-2013. The methodology that is used in paper proposes innovative in this type of analysis and is the decomposition of the value of exports of both commodities in the effects that hypnotize be definers of progress or setbacks in the value of Northeastern exports of both products. The results in the survey show that the Northeast is losing competitiveness relative to its main competitors (Vietnam and India) in the production and export of cashew nuts, both as regards the expansion area harvested as mainly relative yields, an evidence that the Northeastern production of cashew nuts advances in technological gap in relation to its two main competitors in the international market. Considering the production and export of melon by region, the evidence found in the survey suggest advances Northeastern participation in international melon market, demonstrating greater competitiveness compared to the production of this item in the main international competitors are Spain, Guatemala and the United States of America.
166

Strong radiation-matter interaction in a driven superconducting quantum system

Pietikäinen, I. (Iivari) 18 April 2019 (has links)
Abstract In this thesis we study the interaction between radiation and matter using superconducting circuits that behave analogously with the conventional photon-atom interaction in quantum optics. The research is done with a system consisting of a waveguide resonator (radiation) strongly coupled to a transmon device (matter). We focus on the phenomena caused by strong coupling between the radiation and matter, and by driving the resonator to higher excited states with a strong monochromatic radiation. These have been studied little in the traditional radiation-matter systems. Increasing the strength of the monochromatic radiation drive, the dynamics of the system experiences a transition from the quantum to the classical regime. Also, the free-particle states of the transmon start being populated. In the weak driving limit, the transmon can be regarded as a two-state system. As a consequence, the resonator-transmon system is conventionally discussed in terms of the linear Jaynes–Cummings model. However, for strong coupling the Bloch–Siegert shift, caused by the terms neglected in the Jaynes–Cummings model, is strong and the Jaynes–Cummings model is insufficient for describing the dynamics of the system. We study the effects caused by strong coupling and the excitation of the higher transmon states instigated by the driving of the resonator. With reflection spectroscopy, we measure the absorption spectrum of the system and compare this with the spectrum calculated numerically using the Floquet–Born–Markov approach. We find that, in the region of the quantum-to-classical transition, the two-state approximation for the transmon is insufficient and the higher transmon states are necessary for accurate simulations. By calculating the average resonator occupation, we compare different numerical models: the Lindblad master equation, the Floquet–Born–Markov, and the semiclassical model. Coupling a transmon to a resonator shifts the energy levels of the resonator. This shift in the energy levels prevents the higher resonator states from being populated if the system is weakly driven with a frequency that is near the resonance frequency of the resonator. We simulate this photon blockade numerically and show that the blockade is substantially different for the two-state and multistate transmon approximations. / Original papers Original papers are not included in the electronic version of the dissertation. Pietikäinen, I., Danilin, S., Kumar, K. S., Vepsäläinen, A., Golubev, D. S., Tuorila, J., & Paraoanu, G. S. (2017). Observation of the Bloch-Siegert shift in a driven quantum-to-classical transition. Physical Review B, 96(2). https://doi.org/10.1103/PhysRevB.96.020501 http://jultika.oulu.fi/Record/nbnfi-fe201803073899 Pietikäinen, I., Danilin, S., Kumar, K. S., Tuorila, J., & Paraoanu, G. S. (2018). Multilevel Effects in a Driven Generalized Rabi Model. Journal of Low Temperature Physics, 191(5–6), 354–364. https://doi.org/10.1007/s10909-018-1857-8 http://jultika.oulu.fi/Record/nbnfi-fe2018061325770 Pietikäinen, I., Tuorila, J., Golubev, D. S., & Paraoanu, G. S. (2019) Quantum-to-classical transition in the driven-dissipative Josephson pendulum coupled to a resonator, Manuscript. https://arxiv.org/abs/1901.05655
167

A Precise Few-nucleon Size Difference by Isotope Shift Measurements of Helium

Hassan Rezaeian, Nima 08 1900 (has links)
We perform high precision measurements of an isotope shift between the two stable isotopes of helium. We use laser excitation of the 2^3 S_1-2^3 P_0 transition at 1083 nm in a metastable beam of 3He and 4He atoms. A newly developed tunable laser frequency selector along with our previous electro-optic frequency modulation technique provides extremely reliable, adaptable, and precise frequency and intensity control. The intensity control contributes negligibly to overall experimental uncertainty by stabilizing the intensity of the required sideband and eliminating the unwanted frequencies generated during the modulation of 1083 nm laser carrier frequency. The selection technique uses a MEMS based fiber switch and several temperature stabilized narrow band (~3 GHz) fiber gratings. A fiber based optical circulator and an inline fiber amplifier provide the desired isolation and the net gain for the selected frequency. Also rapid (~2 sec.) alternating measurements of the 2^3 S_1-2^3 P_0 interval for both species of helium is achieved with a custom fiber laser for simultaneous optical pumping. A servo-controlled retro-reflected laser beam eliminates residual Doppler effects during the isotope shift measurement. An improved detection design and software control makes negligible subtle potential biases in the data collection. With these advances, combined with new internal and external consistency checks, we are able to obtain results consistent with the best previous measurements, but with substantially improved precision. Our measurement of the 2^3 S_1-2^3 P_0 isotope shift between 3He and 4He is 31 097 535.2 (5) kHz. The most recent theoretic calculation combined with this measurement yields a new determination for nuclear size differences between 3He and 4He: ∆r_c=0.292 6 (1)_exp (8)_th (52)_exp fm, with a precision of less than a part in 〖10〗^4 coming from the experimental uncertainty (first parenthesis), and a part in 〖10〗^3 coming from theory. This value is consistent with electron scattering measurement, but a factor of 10 more precise. It is inconsistent (4 sigma) with a recent isotope shift measurement on another helium transition (2^1 S_0-2^3 S_1). Comparisons with ongoing muonic helium measurements may provide clues to the origin of what is currently called the proton puzzle: electronic and muonic measurements of the proton size do not agree. In the future, the experimental improvements described here can be used for higher precision tests of atomic theory and quantum electrodynamics, as well as an important atomic physics source of the fine structure constant.
168

Développements méthodologiques pour l'analyse d'équilibres conformationnels par résonance magnétique nucléaire / Methodological developments for the analysis of conformational equilibrium by nuclear magnetic resonance spectroscopy.

Aloui, Ghada 18 July 2019 (has links)
La résonance magnétique nucléaire est une technique de choix pour étudier la dynamique de l'échange dans des composés à portée thérapeutique. Cependant, les spectres acquis avec les méthodes 1D et 2D classiques présentent souvent des recouvrements importants, ce qui rend l'attribution de chaque espèce en échange difficile. Le développement méthodologique d'une approche pure shift permettrait donc d'améliorer la résolution de ces données. Au cours de cette thèse, nous avons effectué une série de développements méthodologiques des expériences de type EXSY dans lesquelles nous avons mis en œuvre différentes méthodes de découplage homonucléaire. En particulier, deux approches ont été testées: la méthode PSYCHE appliqué aux dimensions F1 et F2 des cartes EXSY, et la méthode Zangger-Sterk en F2. Ces approches ont toutes mené à une amélioration significative de la résolution qui nous a permis de caractériser les deux conformères s-cis/s-trans du Trandolapril. Nous avons également étudié l’intérêt de la technique d'échantillonnage non-uniforme (NUS) du signal pour réduire le temps d'analyse. Cette approche nous a permis de gagner en temps d'analyse, mais la présence d'artefacts à certaines températures suggère que d'autres développements seront encore nécessaires. Ces résultats ouvrent la voie vers une analyse plus fine du processus d’échange dans des composés présentant un spectre RMN complexe. / Nuclear magnetic resonance is a technique of choice for studying chemical exchange in therapeutic compounds. However, spectra acquired with standard 1D and 2D methods often show spectra with overlapping signals, which makes the assignment of each species difficult. Methodological development of a pure shift approach would therefore make it possible to improve the resolution of these data. During this thesis, we carried out a series of developments of the EXSY type experiments in which we implemented different homonuclear decoupling methods. Two approaches were tested: the PSYCHE method applied to the F1 and F2 dimensions of EXSY maps, and the Zangger-Sterk method in F2. These approaches all led to a significant resolution improvements allowing us to characterize the s-cis/ s-trans conformers in Trandolapril. We have also studied the interest of the non-uniform sampling (NUS) technique to reduce the analysis time. This approach allowed us to accelerate the experiment, but the presence of artifacts at various temperatures suggests that further developments will still be needed. These results pave the way for more analysis of the exchange process in compounds with complex NMR spectrum.
169

Faktorer som påverkar hälsan hos personer som arbetar skift : En systematisk litteraturstudie

Nyman, Kristina, Åman, Ann-Chatrine January 2013 (has links)
<p>Validerat; 20130617 (global_studentproject_submitter)</p>
170

Morningness-Eveningness, Time-Oriented Body Functions, Shift Satisfaction and Anticipated Turnover in a Group of Rotating Shift Workers

Blanca, Angel A. 01 January 1985 (has links) (PDF)
No description available.

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