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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.
11

Analysis of the results and it influence factors of dynamic probing test and interrelation with cone penetration test data in Lithuanian soils / Dinaminio zondavimo rezultatų ir juos įtakojančių veiksnių analizė bei sąsajos su statinio zondavimo duomenimis Lietuvos gruntuose

Žaržojus, Gintaras 30 December 2010 (has links)
The object of the thesis is soils that occur within the territory of Lithuania and may be used as basis for building foundations. The thesis studies the interpretation of the results of Dynamic Penetration Test (DPT) and Cone Penetration Test (CPT) of soils, reliability of direct (number of blows (Nx)) and de-rivative (dynamic point resistance (qd)) DPT parameters, analyses the result influencing factors and interrelation between DPT and CPT parameters. The data analysis has been performed by means of mathematical methods of statistics, also using analytical and empirical solutions. Having examined calculation data it was determined that the indirect parameter of Dy-namic Penetration Test – dynamic point resistance (qd) should not be used due to calculation de-faults and replaced with the direct parameter – number of blows (Nx). The analysis of DPT re-sults influencing factors shows that the lateral overburden pressure together with friction of rods are those with the greatest impact on penetration data. Within the scope of the work, it has re-vealed that the number of blows (Nx) and static cone resistance (qc) are closely correlated and it depends on the grain size distribution of soil, geotechnical properties and depth of occurrence. / Disertacijos objektas yra Lietuvos teritorijoje slūgsantys gruntai, kurie gali būti statinių pamatų pagrindu. Disertacijoje nagrinėjama grunto tyrimo dinaminiu (DPT) ir statiniu (CPT) zondavimu rezultatų interpretacija, tiesioginio (smūgių skaičiaus (Nx)) ir išvestinio (dinaminės kūgio smigos (qd)) DPT rodiklių patikimumas, analizuojami rezultatus įtakojantys veiksniai ir sąsajos tarp DPT bei CPT zondavimo rodiklių. Duomenų analizė atlikta matematiniais statistiniais metodais, taip pat panaudojant analitinius ir empirinius sprendinius. Išnagrinėjus skaičiavimo duomenis buvo nustatyta, kad netiesioginis dinaminio zonda-vimo rodiklis – dinaminė kūgio smiga (qd) dėl skaičiavimo trukumų yra nenaudotinas ir keisti-nas į tiesioginį rodiklį – smūgių skaičių (Nx). DPT rezultatus įtakojančių veiksnių analizė paro-dė, kad zondavimo duomenims didžiausią įtaką turi gruntų šoninis geostatinis slėgis ir kartu zondavimo štangų trintis į gruntą. Darbo metu buvo gauta, kad egzistuoja tamprus koreliacinis ryšys tarp smūgių skaičiaus (Nx) ir statinės kūgio spraudos (qc), kuris priklauso nuo grunto gra-nuliometrinės sudėties, mechaninių savybių ir slūgsojimo gylio.
12

Dinaminio zondavimo rezultatų ir juos įtakojančių veiksnių analizė bei sąsajos su statinio zondavimo duomenimis Lietuvos gruntuose / Analysis of the results and it influence factors of dynamic probing test and interrelation with cone penetration test data in Lithuanian soils

Žaržojus, Gintaras 30 December 2010 (has links)
Disertacijos objektas yra Lietuvos teritorijoje slūgsantys gruntai, kurie gali būti statinių pamatų pagrindu. Disertacijoje nagrinėjama grunto tyrimo dinaminiu (DPT) ir statiniu (CPT) zondavimu rezultatų interpretacija, tiesioginio (smūgių skaičiaus (Nx)) ir išvestinio (dinaminės kūgio smigos (qd)) DPT rodiklių patikimumas, analizuojami rezultatus įtakojantys veiksniai ir sąsajos tarp DPT bei CPT zondavimo rodiklių. Duomenų analizė atlikta matematiniais statistiniais metodais, taip pat panaudojant analitinius ir empirinius sprendinius. Išnagrinėjus skaičiavimo duomenis buvo nustatyta, kad netiesioginis dinaminio zonda-vimo rodiklis – dinaminė kūgio smiga (qd) dėl skaičiavimo trukumų yra nenaudotinas ir keisti-nas į tiesioginį rodiklį – smūgių skaičių (Nx). DPT rezultatus įtakojančių veiksnių analizė paro-dė, kad zondavimo duomenims didžiausią įtaką turi gruntų šoninis geostatinis slėgis ir kartu zondavimo štangų trintis į gruntą. Darbo metu buvo gauta, kad egzistuoja tamprus koreliacinis ryšys tarp smūgių skaičiaus (Nx) ir statinės kūgio spraudos (qc), kuris priklauso nuo grunto gra-nuliometrinės sudėties, mechaninių savybių ir slūgsojimo gylio. / The object of the thesis is soils that occur within the territory of Lithuania and may be used as basis for building foundations. The thesis studies the interpretation of the results of Dynamic Penetration Test (DPT) and Cone Penetration Test (CPT) of soils, reliability of direct (number of blows (Nx)) and de-rivative (dynamic point resistance (qd)) DPT parameters, analyses the result influencing factors and interrelation between DPT and CPT parameters. The data analysis has been performed by means of mathematical methods of statistics, also using analytical and empirical solutions. Having examined calculation data it was determined that the indirect parameter of Dy-namic Penetration Test – dynamic point resistance (qd) should not be used due to calculation de-faults and replaced with the direct parameter – number of blows (Nx). The analysis of DPT re-sults influencing factors shows that the lateral overburden pressure together with friction of rods are those with the greatest impact on penetration data. Within the scope of the work, it has re-vealed that the number of blows (Nx) and static cone resistance (qc) are closely correlated and it depends on the grain size distribution of soil, geotechnical properties and depth of occurrence.
13

Descentralização administrativa: o caso da coordenação regional de polícia técnica do planalto - BA

Mendes, Maurício dos Santos 17 August 2012 (has links)
Submitted by Maurício dos Santos Mendes (maurmendes2006@gmail.com) on 2013-06-05T02:18:58Z No. of bitstreams: 1 Dissertação Final _ Maurício dos Santos Mendes _ Aprovado.pdf: 4531289 bytes, checksum: 55dc62733894d640667bffa8c780b1b8 (MD5) / Rejected by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br), reason: Submissão rejeitada, pois está faltando anexar ao PDF a ficha catalográfica e a folha de aprovação com as assinaturas dos membros da banca. Favor refazer a submissão. Att. ÁUREA SRA on 2013-06-05T15:47:56Z (GMT) / Submitted by Maurício dos Santos Mendes (maurmendes2006@gmail.com) on 2013-06-06T10:25:49Z No. of bitstreams: 1 Dissertação Final _ Maurício dos Santos Mendes _ Aprovado (Final).pdf: 4572710 bytes, checksum: 20dbf03aa8ed88bb5dfd1875088b769d (MD5) / Approved for entry into archive by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br) on 2013-06-06T14:45:27Z (GMT) No. of bitstreams: 1 Dissertação Final _ Maurício dos Santos Mendes _ Aprovado (Final).pdf: 4572710 bytes, checksum: 20dbf03aa8ed88bb5dfd1875088b769d (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2013-06-10T18:21:39Z (GMT) No. of bitstreams: 1 Dissertação Final _ Maurício dos Santos Mendes _ Aprovado (Final).pdf: 4572710 bytes, checksum: 20dbf03aa8ed88bb5dfd1875088b769d (MD5) / Made available in DSpace on 2013-06-10T18:24:01Z (GMT). No. of bitstreams: 1 Dissertação Final _ Maurício dos Santos Mendes _ Aprovado (Final).pdf: 4572710 bytes, checksum: 20dbf03aa8ed88bb5dfd1875088b769d (MD5) Previous issue date: 2012-08-17 / Technical Police Department (DPT) is a Bahia State Public Safety Department agency (SSP/BA), which aims to manage the services in the field of technical scientific police, promoting studies and performing surveys and other procedures, aiming at the expert evidence. DPT has several Regi onal Coordination Centers that are supported by six Bigger Regional Coordination C enters throughout the State. These Bigger Regional Coordination Centers were cre ated to manage a growing demand for expert work through internalization proc ess of Technical Police by Bahia municipalities. The objective of this exploratory s tudy was demonstrating how the administrative decentralization process took place in the Technical Police Regional Coordination Center in Planalto-BA. Thus, we adopte d the procedures of a literature search to ascertain the various concepts of central ization, decentralization, concentration and deconcentration in order to enabl e the main aspects analysis and the administrative decentralization relevance in pu blic administration. By systematic observation, it was described the operation of the Bigger Regional Coordination Center of Planalto-BA and it has been applied semis tructured interview and closed structured questionnaire techniques to listen to th e managers of the Coordination Centers linked to the Bigger Regional Coordination Center of Planalto, among them its Coordinator and DPT directors. Experts who work in the involved Coordination Centers were also interviewed in order to collect d ata that made possible to identify, among administrative activities undertaken by the C oordination, those which have decentralization characteristics. In the end of the study it was possible to conclude that DPT has not still reached the decentralization it aims since 2004, a process that has begun with the Regional Coordination Centers ex pansion in countryside. Field survey revealed various orders shortages that resul t in incomplete and inefficient works without the celerity justice requires. All th is points to the urgency in preparing a comprehensive study that would result in a proposal for procedural and structural standards which could make effective DPT decentrali zation. / O Departamento de Polícia Técnica (DPT) é um órgão da Secretaria de Segurança Pública do Estado da Bahia (SSP/BA), que tem por finalidade gerir os serviços no campo da polícia-técnica-científica, promovendo estudos e realizando exames e outros procedimentos, visando à prova pericial. Possui diversas coordenadorias regionais que recebem suporte das seis coordenações regionais distribuídas pelo interior do Estado. Tais coordenações foram criadas para atender a uma demanda crescente pelos trabalhos periciais ao longo do processo de interiorização da Polícia Técnica pelos municípios baianos. O objetivo do estudo exploratório aqui relatado foi descrever a maneira como o processo de descentralização administrativa se efetivou na Coordenação Regional de Polícia Técnica do Planalto-BA. Para isso, foram adotados os procedimentos de uma pesquisa bibliográfica a fim de aprofundar as definições dos diversos conceitos de centralização, descentralização, concentração e desconcentração, de modo a possibilitar a análise dos principais aspectos e a relevância da descentralização administrativa para a administração pública. Por meio de observação sistemática, foi delineada uma descrição do funcionamento da Coordenação Regional do Planalto-BA e foram empregadas técnicas de entrevista semiestruturada e de aplicação de questionário estruturado fechado para ouvir os dirigentes das coordenadorias vinculadas à Coordenação Regional do Planalto, entre os quais o seu coordenador e as diretorias do DPT. Foram também ouvidos os peritos que laboram nas coordenadorias envolvidas, para colher dados que possibilitaram identificar, dentre as atividades administrativas realizadas pela coordenação, aquelas que apresentam as características da descentralização. Ao final do estudo foi possível concluir que o DPT ainda não alcançou a descentralização que vem almejando desde 2004, processo que iniciou com a interiorização das Coordenadorias Regionais. A pesquisa de campo revelou carências de ordens diversas que resultam em trabalhos incompletos, ineficientes e sem a celeridade que a justiça necessita. Tudo isso aponta para a urgência na elaboração de um estudo aprofundado que tenha como resultado uma proposta de padronização procedimentais e estruturais que tornem efetiva a descentralização do DPT.
14

Immunization coverage and factors associated with failure to complete childhood immunization in Kawempe Division, Uganda

Bataringaya, Cos Kamanda January 2010 (has links)
<p>The aim of the study was to describe immunization coverage for DPT, Polio and Measles among children of ages between 12 to 18 months in Kawempe Division and to investigate factors associated with immunization coverage. A cross-sectional survey was conducted in 239 households with children aged between 12-18 months in five villages that were selected through multi-stage cluster sampling. Information on demographic and socio-economic factors and immunization status was obtained from mothers and caretakers. Immunization coverage and analysis of associations between immunization coverage and demographic and socio-economic factors were done.</p>
15

Immunization coverage and factors associated with failure to complete childhood immunization in Kawempe Division, Uganda

Bataringaya, Cos Kamanda January 2010 (has links)
<p>The aim of the study was to describe immunization coverage for DPT, Polio and Measles among children of ages between 12 to 18 months in Kawempe Division and to investigate factors associated with immunization coverage. A cross-sectional survey was conducted in 239 households with children aged between 12-18 months in five villages that were selected through multi-stage cluster sampling. Information on demographic and socio-economic factors and immunization status was obtained from mothers and caretakers. Immunization coverage and analysis of associations between immunization coverage and demographic and socio-economic factors were done.</p>
16

Immunization coverage and factors associated with failure to complete childhood immunization in Kawempe Division, Uganda

Kamanda, Bataringaya Cos January 2010 (has links)
Magister Public Health - MPH / The aim of the study was to describe immunization coverage for DPT, Polio and Measles among children of ages between 12 to 18 months in Kawempe Division and to investigate factors associated with immunization coverage. A cross-sectional survey was conducted in 239 households with children aged between 12-18 months in five villages that were selected through multi-stage cluster sampling. Information on demographic and socio-economic factors and immunization status was obtained from mothers and caretakers. Immunization coverage and analysis of associations between immunization coverage and demographic and socio-economic factors were done. / South Africa
17

Etude de l'adsorption de l'ozone et du cyanoacétylène sur une surface de glace d'eau: un modèle de chimie du milieu interstellaire

BORGET, Fabien 22 December 2000 (has links) (PDF)
L'adsorption de l'ozone et du cyanoacétylène sur une surface de glace amorphe d'eau a été caractérisée par spectrométrie IRTF entre 10 et 180K. L'ozone s'adsorbe sur les OH libres de surface de la glace et une énergie d'activation de désorption de 20 kJ/mol a été mesurée par Désorption Programmée en Température (DPT) couplée à l'IRTF. Cette valeur a été confirmée par des calculs quantiques ab initio de type périodique et l'interaction a été caractérisée comme étant de type liaison hydrogène. En préliminaire au calcul périodique, les complexes O3•••H2O ont également été modélisés. Le cyanoacétylène montre deux états d'adsorption sur la surface de glace amorphe, le premier, entre 15 et 45 K, se caractérise par l'existence d'une liaison hydrogène entre les OH libres de surface de la glace et l'atome d'azote du cyanoacétylène, le second entre 45 et 110 K, met aussi en jeu une liaison hydrogène entre un doublet libre d'un atome d'oxygène de surface de la glace et l'atome d'hydrogène du cyanoacétylène. L'énergie d'activation de désorption pour le deuxième état, déterminée par DPT, est égale à 39 kJ/mol. Un caractère donneur et accepteur de proton du cyanoacétylène vis à vis de la glace est observé. Ces effets apparaîssent aussi lors de l'étude des complexes cyanoacétylène•••eau en matrice d'argon. Les stabilités relatives ont été déterminées par calcul ab initio. La nature cinétique et thermodynamique des processus d'adsorption est discutée. Une étude préliminaire de la photochimie de l'ozone co-adsorbé sur de la glace amorphe avec du cyanoacétylène a montré la formation de H2O2, de O2 et d'un troisième produit de réaction qui pourrait être un cétène.
18

Comportement viscoplastique avec rupture des argiles raides. Applications aux ouvrages souterrains

Tchiyep Piepi, Guy 17 October 1995 (has links) (PDF)
Les argiles raides sont généralement rencontrées à grande profondeur (plus de 300 mètres). Ces matériaux se caractérisent par leur teneur en eau relativement faible. De nombreux projets industriels justifient l'intérêt récent porté à ces matériaux. La thèse traite en particulier d'argiles raides susceptibles de répondre à des sollicitations par des déformations élastiques, plastiques et viscoplastiques. C'est la prise en compte simultanée d'une rupture engendrant des déformations plastiques et des déformations différées de types viscoplastiques qui font l'originalité de cette thèse. Cette nouvelle approche constitue une amélioration indispensable dans la description du comportement mécanique d'argiles raides. Ce travail est présenté en trois parties : la première partie est consacrée à l'étude expérimentale et à la modélisation du comportement mécanique des argiles raides. Dans cette partie, nous décrivons les matériaux considérés, et les essais réalisés. Nous discutons les résultats et élaborons un modèle viscoplastique avec rupture. La deuxième partie, « Application du modèle VPR au calcul d'un tunnel de section circulaire », est consacrée à l'élaboration d'une solution originale semi analytique et d'un algorithme implanté dans GEOMEC91. La troisième partie, « Application du modèle VPR au calcul 2d axisymétrique des tunnels soutenus et étude paramétrique », montre très clairement l'influence du modèle VPR sur la convergence du tunnel au moment de la pose du soutènement, et par conséquent sur les sollicitations de ce dernier. Les résultats des calculs montrent une forte influence de la cohésion à court terme sur la convergence du tunnel.
19

[en] THE HYBRID BOUNDARY ELEMENT METHOD FOR GRADIENT ELASTICITY PROBLEMS / [pt] O MÉTODO HÍBRIDO DE ELEMENTOS DE CONTORNO PARA PROBLEMAS DE ELASTICIDADE GRADIENTE

DANIEL HUAMAN MOSQUEIRA 28 January 2015 (has links)
[pt] Atualmente está bem difundido o uso de novas modelagens matemáticas para o estudo do comportamento de micro e nano sistemas mecânicos e eléctricos. O problema de escala é notável quando o tamanho das moléculas, partículas, grãos ou cristais de um sólido é relativamente considerável em relação ao comprimento do microdispositivo. Nesses casos a teoria clássica dos meios contínuos não descreve apropriadamente a solicitação estrutural e é necessária uma abordagem mais geral através de teorias generalizadas não-clássicas que contém a elasticidade clássica como um caso particular delas, onde os parâmetros constitutivos que representam às partículas são desprezíveis. Quando os efeitos microestruturais são importantes, o comportamento não responde como um material homogêneo se não como um material homogêneo. Cem anos atrás os irmãos Cosserat desenvolveram uma teoria de grãos rígidos imersos dentro de um macromeio elástico; posteriormente Toupin, Mindlin e outros pesquisadores na década de 60 formularam a chamada teoria gradiente de deformações, que recentemente é um objeto de muitas investigações analíticas e experimentais. Na década de oitenta, Aifantis e colaboradores conseguiram desenvolver uma teoria de gradiente de deformações simplificada, baseada em só uma constante elástica adicional não-clássica representativa da energia de deformação volumétrica para caracterizar satisfatoriamente os padrões dos fenômenos não-clássicos. Beskos e colaboradores estenderam o campo de aplicações da proposta inicial de Aifantis e fizeram as primeira implementações de elementos de contorno 2D e 3D para análises de elasticidade gradiente estática, no domínio da frequência e a mecânica da fratura. Desde o tempo de Toupin e Mindlin, procura-se estabelecer uma base variacional da teoria e uma formulação consistente das condições de contorno cinemáticas e de equilíbrio, o que parece ter tido êxito com os recentes trabalhos de Amanatidou e Aravas. Esta tese apresenta a formulação do método híbrido de elementos de contorno e finitos na elasticidade gradiente desenvolvida por Dumont e Huamán decompondo o potencial de Hellinger-Reissner em dois princípios de trabalhos virtuais: o primeiro em deslocamentos virtuais e o segundo em forças virtuais. Com esta finalidade é considerado além dos parâmetros clássicos, o trabalho realizado pelas tensões, deformações, forças e deslocamentos não-clássicos. É apresentado o desenvoltimento das soluções fundamentais singulares e polinomiais atráves das equações diferenciais de sexta ordem obtidas da equação de equilíbrio em termos de deslocamento na elasticidade gradiente. É apresentada também a aplicaçõ do método híbrido de contorno para problemas de tensão axial unidimensional e flexão bidimensional de vigas. Finalmente mostra-se a aplicação numérica do método em elementos finitos, é verificado o patch test de elementos finitos de diferentes ordem e mostra-se também análises de convergência. / [en] The use of new mathematical modeling in the study of micro and Nano electro mechanical systems is currently becoming widespread. The scaling problem is apparent when the length of molecules, particles or grains immersed in the material is relatively important compared with the whole micro device dimension. Under this approach the classical theories of mechanics cannot describe suitably the structural requirement and it is necessary a more general outlook through non classical generalized theories which enclose the classical elasticity as a particular case where the non-classical constitutive parameters are negligible. When the microstructural effects are important, the material does not respond as a homogeneous but as a non-homogeneous one. A hundred years ago Cosserat brothers formulated a new theory of rigid grains which were embedded in an elastic macro medium; later Toupin, Mindlin along others researchers in 1960s developed a gradient strain theory which has been recently the source of many analystics and experimental investigations. In 1980s Ainfantis et al could develop a simplified strain gradient theory with just one additional non classical elastic constant which represents the volumetric elastic strain energy and characterized successfully the whole non classical pattern phenomenon. Beskos et al extended the treatment proposed initially by Aifantis and developed the first numerical applications for 2D and 3D boundary element methods and solved static as dynamic and crack problems. Since the times of Toupin and Mindlin it is looking for to establish a variational theory with a consistent cinematic and equilibrium boundary conditions, which seemed to have had success in the recent works of Amanatiodou and Aravas. This work presents the formulation of the hybrid boundary and finite element methods under the strain gradient scope which were developed by Dumont and Huamán through the versatile decomposition of the Hellinger-Reissner potential in two work principles: the displacements virtual work and the forces virtual work; both principles contain the virtual work performed by the non-classical magnitudes. Following, it is presented the complete development of singular and polynominal fundamental solutions abtained through the sixth order strain gradient differential equilibrium equations in terms of displacements. Next it is shown an application of the method to unidimensional truss element and bidimensional beam. Finally, it is presented a numerical application to strain gradient finite element, it is checked the patch tests to different elements orders and it is also shown a series of convergence analysis.

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