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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.
101

Potentiel de la mesure GPS sol pour l'étude des pluies intenses méditerranéennes.

Brenot, Hugues 18 January 2006 (has links) (PDF)
La zone Cévennes-Vivarais et son extension jusque la Méditerranée a été choisie par l'OHM-CV (Observatoire Hydrométéorologique-Méditerranéen des Cévennes-Vivarais) pour la fréquence et la représentativité des événements de pluies intenses qu'elle subit. Depuis 2002, des campagnes automnales de mesures GPS y sont menées dans le but d'améliorer notre connaissance du champ de vapeur d'eau troposphérique associé aux événements de pluie intense. Les observations GPS météorologiques sont les ZTD (délais troposphériques au zénith) et les gradients de délais. Exprimé par une composante Est-Ouest (Gew) et une composante Nord-Sud (Gns), le gradient de délai traduit l'anisotropie du champ de vapeur d'eau à proximité du site GPS.Pour le traitement des observations GPS des réseaux permanents et temporaires de la région de l'OHM-CV, une configuration optimale a été recherchée à partir de différents tests de sensibilité. Une précision de 5 mm sur les ZTD peut être obtenue avec cette stratégie d'analyse pour le réseau régional GPS de la région de l'OHM-CV ; Gew est précis à 6 mm près, alors que Gns apparaît moins précis (à 12 mm près) du fait de l'absence de satellite survolant le pôle Nord.Afin de préparer l'assimilation des observations GPS par les systèmes d'assimilation de données à méso-échelle de Météo-France (modèle de Météo-France AROME), des simulateurs d'observations GPS (ZTD, STD et gradients) ont été implémentés dans le modèle non-hydrostatique à haute résolution Méso-NH. Le laboratoire numérique que constitue le modèle Méso-NH a été un moyen efficace de quantifier la sensibilité des simulations de délais à différentes formulations de la réfractivité atmosphérique.
102

Architecture logicielle : une expérimentation industrielle avec Dassault Systèmes

Sanlaville, Rémy 03 May 2002 (has links) (PDF)
L'architecture logicielle est un domaine récent du génie logiciel qui a reçu une attention particulière ces dix dernières années. Les éditeurs de logiciels ont pris conscience qu'une architecture est un facteur critique dans la réussite du développement et facilite la maintenance et l'évolution du logiciel. Elle contribue à la maîtrise des grands logiciels. L'architecture logicielle permet d'améliorer ces aspects grâce à l'étude des structures de haut niveau du logiciel. De nombreuses avancées ont été proposées au niveau de la formalisation par des Langages de Description d'Architecture (ADLs: Architecture Description Languages), du raisonnement et de l'analyse au niveau architectural. Bien que la communauté scientifique ait réalisé des progrès significatifs, les résultats restent essentiellement académiques. Les retombées de ces recherches ont du mal à pénétrer le milieu industriel. Ce rapport de thèse relate notre expérience avec Dassault Systèmes : répondre aux besoins de Dassault Systèmes pour le développement de ses logiciels en utilisant une approche basée sur l'architecture logicielle. Dassault Systèmes est le leader mondial de la Conception Assistée par Ordinateur (CAO) avec son logiciel phare CATIA V5 (~5 MLoc). Pour atteindre cet objectif, nous avons parcouru les principales approches pour la description d'une architecture logicielle et tenté de les appliquer dans notre contexte industriel. Nous expliquerons les difficultés que nous avons rencontrées pour les utiliser et montrerons pourquoi ces approches ne sont pas adaptées pour la maintenance et l'évolution d'un logiciel tel que CATIA V5. Nous décrirons notre démarche basée sur l'analyse des besoins architecturaux des différents acteurs de Dassault Systèmes qui a permis de fournir des solutions concrètes et exploitables. Enfin, nous expliciterons ces besoins architecturaux et présenterons les divers prototypes que nous avons développés pour y répondre.
103

Spacecraft Interface Standards Analysis and Simple Breadboarding

Ljunggren, Birgitta January 2005 (has links)
<p>This report is a result of a thesis work done for Linköping University at Contraves Space AG in Zürich, Switzerland. The aim was to perform an analysis of 12 interface standards and construct a simple breadboard, which should function as a testsystem for the data communication interface MIL-STD-1553. </p><p>The conclusion of the extensive analysis is that SpaceWire, MIL-STD-1553 and CAN are the most interesting interfaces for future data communication in spacecrafts. In the breadboard part of the work, a test system was built and data gathered with help from a demonstration program that came with one of the components.</p>
104

Contributions to channel modelling and performance estimation of HAPS-based communication systems regarding IEEE Std 802.16TM

Palma Lázgare, Israel Romualdo 24 October 2011 (has links)
New and future telecommunication networks are and will be broadband type. The existing terrestrial and space radio communication infrastructures might be supplemented by new wireless networks that make and will make use of aeronautics-technology. Our study/contribution is referring to radio communications based on radio stations aboard a stratospheric platform named, by ITU-R, HAPS (High Altitude Platform Station). These new networks have been proposed as an alternative technology within the ITU framework to provide various narrow/broadband communication services. With the possibility of having a payload for Telecommunications in an aircraft or a balloon (HAPS), it can be carried out radio communications to provide backbone connections on ground and to access to broadband points for ground terminals. The latest implies a complex radio network planning. Therefore, the radio coverage analysis at outdoors and indoors becomes an important issue on the design of new radio systems. In this doctoral thesis, the contribution is related to the HAPS application for terrestrial fixed broadband communications. HAPS was hypothesised as a quasi-static platform with height above ground at the so-called stratospheric layer. Latter contribution was fulfilled by approaching via simulations the outdoor-indoor coverage with a simple efficient computational model at downlink mode. This work was assessing the ITU-R recommendations at bands recognised for the HAPS-based networks. It was contemplated the possibility of operating around 2 GHz (1820 MHz, specifically) because this band is recognised as an alternative for HAPS networks that can provide IMT-2000 and IMT-Advanced services. The global broadband radio communication model was composed of three parts: transmitter, channel, and receiver. The transmitter and receiver parts were based on the specifications of the IEEE Std 802.16TM-2009 (with its respective digital transmission techniques for a robust-reliable link), and the channel was subjected to the analysis of radio modelling at the level of HAPS and terrestrial (outdoors plus indoors) parts. For the channel modelling was used the two-state characterisation (physical situations associated with the transmitted/received signals), the state-oriented channel modelling. One of the channel-state contemplated the environmental transmission situation defined by a direct path between transmitter and receiver, and the remaining one regarded the conditions of shadowing. These states were dependent on the elevation angle related to the ray-tracing analysis: within the propagation environment, it was considered that a representative portion of the total energy of the signal was received by a direct or diffracted wave, and the remaining power signal was coming by a specular wave, to last-mentioned waves (rays) were added the scattered and random rays that constituted the diffuse wave. At indoors case, the variations of the transmitted signal were also considering the following matters additionally: the building penetration, construction material, angle of incidence, floor height, position of terminal in the room, and indoor fading; also, these indoors radiocommunications presented different type of paths to reach the receiver: obscured LOS, no LOS (NLOS), and hard NLOS. The evaluation of the feasible performance for the HAPS-to-ground terminal was accomplished by means of thorough simulations. The outcomes of the experiment were presented in terms of BER vs. Eb/N0 plotting, getting significant positive conclusions for these kind of system as access network technology based on HAPS.
105

Spacecraft Interface Standards Analysis and Simple Breadboarding

Ljunggren, Birgitta January 2005 (has links)
This report is a result of a thesis work done for Linköping University at Contraves Space AG in Zürich, Switzerland. The aim was to perform an analysis of 12 interface standards and construct a simple breadboard, which should function as a testsystem for the data communication interface MIL-STD-1553. The conclusion of the extensive analysis is that SpaceWire, MIL-STD-1553 and CAN are the most interesting interfaces for future data communication in spacecrafts. In the breadboard part of the work, a test system was built and data gathered with help from a demonstration program that came with one of the components.
106

Dynamic Systems: Evaluation, Screening and Synthetic Application

Sakulsombat, Morakot January 2011 (has links)
The research work reported in the thesis deals with the development of dynamic covalent systems and their applications in evaluation and screening of protein-ligands and enzyme inhibitors, as well as in synthetic methodologies. The thesis is divided into four parts as described below. In part one, synthetic methodologies to access 3-functionalized phthalides and 3-thioisoindolinones using the concept of cascade reactions are demonstrated. Efficient syntheses of the target products are designed and performed in one-pot process under mild reaction conditions.  In part two, phosphine-catalyzed disulfide metathesis for the generation of dynamic carbohydrate system in aqueous solution is demonstrated. In the presence of biological target (Concanavalin A), the optimal dynamic ligand is successfully identified in situ by the 1H STD-NMR spectroscopy. In part three, lipase-catalyzed resolutions of dynamic reversible systems using reversible cyanohydrin and hemithioacetal reactions in one-pot processes are demonstrated. The dynamic systems are generated under thermodynamic control in organic solution and subsequently resolved by lipase-mediated resolution under kinetic control. The resolution processes resulted in the lipase-selected substrates with high structural and stereochemical specificities. In the last part, dynamic fragment-based strategy is presented using β-galactosidase as a model target enzyme. Based on our previous study, the best dynamic inhibitor of β-galactosidase was identified using 1H STD-NMR technique from dynamic hemithioacetal systems. The structure of the dynamic inhibitor is tailored by fragment linking and optimization processes. The designed inhibitor structures are then synthesized and tested for inhibition activities against β-galactosidase. / QC 20110526
107

Da invisibilidade à vulnerabilidade: percursos do corpo lésbico na cena contemporânea brasileira face à possibilidade de infecção por DST e AIDS / Female sexuality; lesbians; lesbianism; STD / AIDS

Guilherme Silva de Almeida 30 June 2005 (has links)
A produção acadêmica motivada pela epidemia de HIV e Aids impulsionou as pesquisas relativas à sexualidade configurando novos campos de investigação, em especial sobre os gays. No entanto, não é significativa no Brasil a produção acadêmica que aborde a vulnerabilidade às DSTs a partir da identidade lésbica. A saúde sexual das mulheres presumidamente heterossexuais tendeu a permanecer subsumida à exclusiva preocupação com a reprodução ao longo da trajetória das políticas de atenção à saúde das mulheres, mesmo frente à Aids. De forma ainda mais acentuada que a sexualidade feminina heterossexual, a homossexualidade feminina tendeu à invisibilidade na sociedade brasileira e frente ao discurso médico-ginecológico. O advento da epidemia contribuiu para a manutenção desta invisibilidade por força da crença de que o corpo lésbico seria o único infenso à infecção pela via sexual. Nesta tese busca-se compreender a transformação discursiva do corpo lésbico dos primeiros tempos da epidemia até hoje. Mais especificamente, como um corpo imune à epidemia está calcada na idéia de que a vulnerabilidade das lésbicas é o passaporte para a afirmação/inclusão de um dado marco identitário na agenda de políticas públicas. Nesse sentido, o campo em que se desenha a disputa do corpo lésbico face às DST/Aids é marcado pela tensão entre prática sexual e identidade sexual. / The academical production motivated by HIV and Aids epidemic has impelled researches related to the sexuality configurating new investigations fields, mainly about gays. However, in Brazil, its not significant the academical production which addresses to the STD vulnerability taking into an account the lesbian identity. The sexual health of women, expected to be heterosexual, was be connected to the unique preoccupation about the reproduction. Along the course of policies in terms of the attention to the womens health, even facing AIDS. In a more increasing way, considering the heterosexual female sexuality, the female homo sexual has tended, on the Brazilian society, to the invisibility toward the medical / gynaecologic speech. The epidemic contributed to this invisibility maintenance by strong beliefs in which the lesbian body would be the unique immune to the infection through the sexual via. This thesis objectives is based on the study about the change regarding the speech construction of the lesbian body since the first stages of the epidemic. More specifically, how a body that is immune to the epidemic is transformed into a vulnerable body. The hypothesis that guides this paper is centered on the idea in which the lesbian vulnerability is the passport to the affirmation / inclusion of a certain marl of identity in public policies. This way, the field in which the lesbian body dispute is drawn regarding STDs/AIDS is marked by tension between sexual practice and sexual identity.
108

Analýza kvality spolupráce mezi vybranými zdravotnickými zařízeními a orgánem ochrany veřejného zdraví v oblasti detekce a hlášení pohlavně přenosných nemocí. / Analysis of the Quality of Cooperation between the Selected Health Facilities and Public Health Protection Authority in the Detection and Reporting of Sexually Transmitted Diseases.

ŠVECOVÁ, Pavla January 2012 (has links)
My theses deal with evaluation of the level of cooperation among chosen medical facilities and organs protecting public health (OOVZ) in the area of detection and reporting some of sexually transmitted diseases (STD) in Strakonice region. The main objective was to characterize the quality of this cooperation on the basis of an analysis of laboratory-proven, clinically confirmed, reported and then demonstrated cases of STDs. It concerned chlamydial infections, urogenital diseases caused by mycoplasma, syphilis and gonococcal infections in 2005 - 2011. Research data were obtained from the microbiology laboratory information system of the Central Laboratories of Hospital Strakonice, Inc. Then all the medical facilities of the surrounding area, which took biological material and sent it for examination to the microbiological laboratory of Hospital Strakonice, were contacted. In qualitative research two research questions were formulated: whether the laboratory-positive cases of selected sexually transmitted diseases are also confirmed clinically and whether the laboratory and clinically confirmed diseases are reported in all cases to OOVZ and assigned in health information systems services. All positive laboratory findings were also verified and confirmed clinically. The research proved that in all cases were reported classical sexually transmitted infections (syphilis and gonorrhea). The established system of cooperation between microbiological laboratories, national reference laboratories, dermatovenerological consultant, venereological screening nurse and the Public Health Service is very functional. In contrast, other selected sexually transmitted diseases, which are diagnosed by specialists other than dermatovenerologists, are reported in fewer cases.
109

Prevalência de Neisseria gonorrhoeae e Chlamydia trachomatis em homens atendidos em clínicas de DST de seis capitais brasileiras

Barbosa, Marcelo Joaquim 12 July 2010 (has links)
Made available in DSpace on 2016-12-23T13:56:05Z (GMT). No. of bitstreams: 1 Marcelo Joaquim Barbosa.pdf: 493310 bytes, checksum: 1cc616c331737b5497291791ef93fb83 (MD5) Previous issue date: 2010-07-12 / Objetivos: Determinar a prevalência de Neisseria gonorrhoeae (NG) e Chlamydia trachomatis (CT) e identificar fatores demográficos, comportamentais e clínicos correlacionados a essas infecções em homens atendidos em seis clínicas de DST no Brasil. Métodos: Estudo multicêntrico, em corte transversal realizado em homens que procuraram atendimento em clínicas de DST. O estudo incluiu clínicas de DST em seis cidades distribuídas nas cinco macrorregiões do Brasil, 2004/2005. Metodologia: Coletou-se 20 ml do primeiro jato de urina para testar NG e CT por DNA-PCR. Resultados: Um total de 767 (92,9%) homens foi incluído no estudo. A mediana de idade foi de 24 (DIQ21 30) anos. A prevalência de infecção por CT foi 13,1% (IC95% 10,7%-15,5%) e por NG 18,4% (IC95% 15,7%-21,1%). A prevalência de coinfecção foi 4,4% (IC95% 2,95%-5,85%). Os fatores identificados como sendo independentemente associados com a infecção por clamídia no modelo final de regressão logística foram: ser jovem (15-24 anos) [OR=1,4 (IC95% 1,01-1,91)], apresentar corrimento uretral ao exame [OR=4.8 (IC95% 1,52-15,05)], verrugas genitais [OR=3,0 (IC95% 1,49-5,92)] e história prévia de corrimento uretral [OR=2,4 (IC95% 1,11-5,18)]. As variáveis associadas com gonorréia foram: ser jovem (15-24 anos) [OR=1,5 (IC95% 1,09-2,05)], apresentar corrimento uretral ao exame [OR=9,9 (IC95% 5,53-17,79)], verrugas genitais [OR=18,3 (IC95% 8,03-41,60)] e úlcera ao exame clínico [OR=4,9 (IC95% 1,06-22,73)]. Conclusões: Estes resultados mostram implicações importantes na realização de diagnóstico e tratamento precoces para evitar a transmissão, complicações e implementação de medidas de educação em saúde direcionadas aos homens e deve ser estimulado o oferecimento de testes para DST na rotina dos nos serviços. / Objectives: To determine the prevalence of Neisseria gonorrhoeae(NG) and Chlamydia trachomatis (CT) infections and identified demographic, behavioral, and clinical correlates of these infections in men attending six STI clinics in Brazil. Methods: Multicentric, cross-sectional study performed among men attending STI clinics in Brazil. The study included STD clinics in six diverse cities in the five geographic regions of Brazil in 2005. Patients provided 20 ml of first catch urine for testing for NG and CT by DNA-PCR. Results: A total of 767 (92.9%) men were included in the study. The median age was 24 (IQR 21 30) years old. Prevalence of Chlamydia infection was 13.1% (95%CI 10.7%-15.5%) and gonorrhea was 18.4% (95%CI 15.7%-21.1%). Coinfection prevalence was 4.4% (95%CI 2.95%-5.85%) in men who sought assistance in STI clinics. Factors identified as being independently associated with Chlamydia trachomatis in the final multiple logistic model were being younger (15-24) [OR=1.4 (95%CI 1.01-1.91)], present urethral discharge [OR=4.8 (95%CI 1.52-15.05)], genital warts [OR=3.0 (95%CI 1.49-5.92)] and previous history of urethral discharge [OR=2.4 (95%CI 1.11-5.18)]. Variables associated with gonorrhea were being younger (15 to 24) [OR=1.5 (95%CI 1.09-2.05)], presence of urethral discharge [OR=9.9 (95%CI 5.53-17.79)], genital warts [OR=18.3 (95%CI 8.03-41.60)] and ulcer in clinical examination [OR=4.9 (95%CI 1.06-22.73)]. Conclusions: These findings have important implications for implementing education and prevention efforts directed toward men at risk of HIV/STD. A venue-based approach to offer routinely testing to men in STD clinic should be stimulated.
110

Prevalência de Neisseria gonorrhoeae e Chlamydia trachomatis em homens atendidos em clínicas de DST de seis capitais brasileiras

Barbosa, Marcelo Joaquim 12 July 2010 (has links)
Made available in DSpace on 2016-12-23T13:56:06Z (GMT). No. of bitstreams: 1 Dissertacao de Marcelo Joaquim Barbosa.pdf: 493316 bytes, checksum: 05c09f00c2dba0603712d1b6f468b750 (MD5) Previous issue date: 2010-07-12 / Objetivos: Determinar a prevalência de Neisseria gonorrhoeae (NG) e Chlamydia trachomatis (CT) e identificar fatores demográficos, comportamentais e clínicos correlacionados a essas infecções em homens atendidos em seis clínicas de DST no Brasil. Métodos: Estudo multicêntrico, em corte transversal realizado em homens que procuraram atendimento em clínicas de DST. O estudo incluiu clínicas de DST em seis cidades distribuídas nas cinco macrorregiões do Brasil, 2004/2005. Metodologia: Coletou-se 20 ml do primeiro jato de urina para testar NG e CT por DNA-PCR. Resultados: Um total de 767 (92,9%) homens foi incluído no estudo. A mediana de idade foi de 24 (DIQ21 30) anos. A prevalência de infecção por CT foi 13,1% (IC95% 10,7%-15,5%) e por G 18,4% (IC95% 15,7%-21,1%). A prevalência de coinfecção foi 4,4% (IC95% 2,95%-5,85%). Os fatores identificados como sendo independentemente associados com a infecção por clamídia no modelo final de regressão logística foram: ser jovem (15-24 anos) [OR=1,4 (IC95% 1,01-1,91)], apresentar corrimento uretral ao exame [OR=4.8 (IC95% 1,52-15,05)], verrugas genitais [OR=3,0 (IC95% 1,49-5,92)] e história prévia de corrimento uretral [OR=2,4 (IC95% 1,11-5,18)]. As variáveis associadas com gonorréia foram: ser jovem (15-24 anos) [OR=1,5 (IC95% 1,09-2,05)], apresentar corrimento uretral ao exame [OR=9,9 (IC95% 5,53-17,79)], verrugas genitais [OR=18,3 (IC95% 8,03-41,60)] e úlcera ao exame clínico [OR=4,9 (IC95% 1,06-22,73)]. Conclusões: Estes resultados mostram implicações importantes na realização de diagnóstico e tratamento precoces para evitar a transmissão, complicações e implementação de medidas de educação em saúde direcionadas aos homens e deve ser estimulado o oferecimento de testes para DST na rotina dos nos serviços / Objectives: To determine the prevalence of Neisseria gonorrhoeae(NG) and Chlamydia trachomatis (CT) infections and identified demographic, behavioral, and clinical correlates of these infections in men attending six STI clinics in Brazil. Methods: Multicentric, cross-sectional study performed among men attending STI clinics in Brazil. The study included STD clinics in six diverse cities in the five geographic regions of Brazil in 2005. Patients provided 20 ml of first catch urine for testing for NG and CT by DNA-PCR. Results: A total of 767 (92.9%) men were included in the study. The median age was 24 (IQR 21 30) years old. Prevalence of Chlamydia infection was 13.1% (95%CI 10.7%-15.5%) and gonorrhea was 18.4% (95%CI 15.7%-21.1%). Coinfection prevalence was 4.4% (95%CI 2.95%-5.85%) in men who sought assistance in STI clinics. Factors identified as being independently associated with Chlamydia trachomatis in the final multiple logistic model were being younger (15-24) [OR=1.4 (95%CI 1.01-1.91)], present urethral discharge [OR=4.8 (95%CI 1.52-15.05)], genital warts [OR=3.0 (95%CI 1.49-5.92)] and previous history of urethral discharge [OR=2.4 (95%CI 1.11-5.18)]. Variables associated with gonorrhea were being younger (15 to 24) [OR=1.5 (95%CI 1.09-2.05)], presence of urethral discharge [OR=9.9 (95%CI 5.53-17.79)], genital warts [OR= 8.3 (95%CI 8.03-41.60)] and ulcer in clinical examination [OR=4.9 (95%CI 1.06-22.73)]. Conclusions: These findings have important implications for implementing education and prevention efforts directed toward men at risk of HIV/STD. A venue-based approach to offer routinely testing to men in STD clinic should be stimulated

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