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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.
121

Caracterização geoelétrica de alvos rasos no Sítio Controlado de Geofísica Rasa-II - IAG/USP através do uso de resistividade capacitiva / Capacitive resistivity applied to geoelectric characterization of shallow targets at Sítio Controlado de Geofísica Rasa - II - IAG/USP.

Vitor Lucas Sobottka Cavenaghi 01 November 2017 (has links)
O presente trabalho teve como objetivo determinar as vantagens e limitações do método geofísico de resistividade capacitiva na identificação de materiais enterrados de diferentes tamanhos e propriedades físicas e em diversas profundidades, localizados no Sítio Controlado de Geofísica Rasa II (SCGR-II), em frente ao IAG-USP. Para isso, a COMGAS, em parceria com o IAG-USP adquiriu o equipamento OhmMapper, possibilitando a aquisição de dados através do método capacitivo. Anteriormente à aquisição dos dados de campo, foram adquiridos os valores de resistividade aparente referentes ao background da área, para então realizar a instalação dos alvos. Após a instalação do sítio controlado, determinou-se a melhor técnica de aquisição em relação ao objetivo proposto, mostrando-se a técnica de aquisição contínua, com marcação de posição a cada 10m a mais adequada para o projeto em questão. Com a definição da melhor técnica de aquisição de dados, foi realizada a modelagem sintética dos alvos para que os resultados fossem confrontados com os obtidos em campo; a modelagem demonstrou que o método sintético utilizado (descrito no item 6.2) é capaz de definir contrastes de resistividade em profundidades inferiores a 0,8m e em alvos que apresentem dimensões de no mínimo 10cm. Para a avaliação do método capacitivo, realizou-se após a aquisição dos dados, uma análise 2D e 3D das anomalias. A análise dos dados reais demonstrou boa correlação com os ensaios sintéticos, exceto para alvos metálicos que apresentaram forte anomalia condutiva, enquanto que os mesmos alvos apresentaram anomalias resistivas no modelo criado. A análise das seções 2D do SCGR-II demonstrou boa resposta do método capacitivo utilizado para a caracterização geoelétrica de tambores de plástico cheios de água, tambores de aço vazios , cano metálico e tubos de cerâmica e PVC com água anomalias condutivas, tambores de plástico vazios, manilhas de concreto de grande diâmetro e vazias, caixa de areia acoplada a tubo vertical de PVC, vasos de cerâmica vazios, caixa com material cerâmico, caixa com brita de granito, tubos de PEAD vazios e tubos de polietileno e PVC de pequeno diâmetro e em até 0,5m de profundidade anomalias resistivas. Os dados 3D sumarizam as anomalias apresentadas nas diversas seções 2D, auxiliando na visualização dos contornos condutivos e resistivos do SCGR-II. Recomenda-se que a caracterização dos alvos pontuais seja, sempre que possível, realizada com o uso mútuo de no mínimo dois equipamentos distintos em suas técnicas e métodos, de forma a se evitar a interpretação precipitada das anomalias observadas e a reduzir os erros implícitos a interpretação, garantindo boa correlação com os dados diretos de campo. / The present work had as objective to determine the advantages and limitations of the capacitive resistivity method in the identification of buried materials with different dimensions, physical properties and located at different depths, at the Shallow Controlled Geophysical Site II (SCGR-II) IAG-USP. For this, the enterprise COMGAS, in partnership with the IAG-USP, acquired the capacitive equipment OhmMapper, enabling a data acquisition through the capacitive method. Previously to the acquisition of field data for the SCGR-II targets, the background apparent resistivity of the area were acquired, and then the targets were installed. After the installation of the targets, several acquisitions of test data were performed to define the best acquisition technique for the proposed objective, showing the technique of continuous acquisition, with mark spacing every 10m, the most appropriate for the project. After setting the best technique data acquisition, a synthetic modeling of the targets was done so that the results were compared with the field data; The modeling showed that the synthetic method used (described in item 6.2) is able to define resistivity contrasts in depths lower than 0.8m and in targets that have dimensions of at least 10cm. For the evaluation of the capacitive method, a 2D and 3D analysis of the anomalies was performed with the field data. The results showed a good correlation with the synthetic model, except to metallic targets that presented strong conductive anomaly, whereas the same targets at the modeling presented resistive anomalies. The analysis of the 2D sections at SCGR-II demonstrated that the capacitive method used for the geoelectric characterization got good responses for water filled plastic drums, empty steel drums, metal pipe and ceramic and PVC pipes with water - conductive anomalies, empty plastic drums, empty concrete sleeves with large diameter, sandbox coupled with a vertical PVC pipe, empty ceramic pots, box with ceramic material, box with crushed granite, empty PEAD pipes and tubes of polyester and small diameter PVC that is located up to 0.5m depth - resistive anomalies. The 3D data summarized the anomalies presented in the 2D sections, contributing to a better evaluation of the conductive and resistive contours observed on the sections of SCGR-II. It is recommended that the characterization of punctual targets, whenever possible, carried out with the mutual use of at least two different equipments which work with distinct techniques and methods, in order to avoid a hasty interpretation of the observed anomalies and to reduce the implicit errors in the interpretation, improving the geophysical correlation with direct field data.
122

Localization of both type 2 angiotensin II receptors and a non-angiotensin II binding site by [125 I] CGP42112 in rat brain stem

Roulston, Carli L. (Carli Lorraine), 1973- January 2001 (has links)
Abstract not available
123

Estudio de la Reactividad de Ligandos Pirazólicos 1,3,5-sutituidos con Pd(II) y Pt(II)

Pérez Martínez, José Antonio 11 March 2004 (has links)
En esta tesis se han sintetizado pirazoles 1,3,5-sustituidos con grupos fenilo, piridilo y metilo en las posiciones 3,5 y grupos alquilalcohol y alquilpoliéter en la posición N1 (CH2CH2OH, (CH2CH2O)nCH3; n=3,4).Se ha estudiado la complejación de algunos de los ligandos 1,3,5-sustituidos, previamente sintetizados, con MCl2(CH3CN)2, (M= Pd(II), Pt(II)) y Pd(CH3COO)23. Se ha estudiado la reactividad de algunos de los complejos de Pd(II) y Pt(II) sintetizados, con distintas sales de Ag(I), a fin de obtener diferentes entornos para estos metales. El conjunto de ligandos y complejos sintetizados se han caracterizado por análisis elemental, conductividad, espectroscopia de IR y RMN de 1H, 13C1H, MC, COSY, NOESY, espectrometría de masas, espectroscopia UV-Vis y difracción de Rayos X en monocristal siempre que sea posible.Aplicaciones:Se han realizado estudios con algunos de los ligandos pirazólicos 1,3,5-sustituidos con el fin de evaluarlos como ionóforos, formando parte de Electrodos Selectivos a Iones (Pb2+, Cd2+, Cu2+).Además, se han estudiado algunos complejos de Pd(II) y Pt(II) como nuevos anticancerígenos, a fin de evaluar la influencia del metal así como de los diferentes entornos del metal. / In this thesis, several ligands have been synthesized, including pyrazole derived ligands with phenyl, pyridyl, and methyl moieties in 3 and 5 positions of the pyrazole ring and alkyl-alcohol and alkyl-polyether moieties in position N1 (CH2CH2OH, (CH2CH2O)nCH3; n = 3, 4).Complexation of some of these ligands has been studied towards Pd(II) and Pt(II). Initial complexes used were MCl2(CH3CN)2, (M = Pd(II), Pt(II)) and Pd(CH3COO)23.Reactivity on some of these Pd(II) and Pt(II) complexes has been performed, forcing the precipitation of the chloride ligands with several Ag(I) complexes.All the ligands and complexes obtained in this thesis were characterized by elemental analyses, conductivity measurements, spectroscopy of UV-vis, IR and NMR (1H, 13C, HMQC, COSY, NOESY...), mass spectrometry, and X-ray crystal diffraction (when possible).Some of the ligands have been used as ionopheres in Ion Selective Electrodes (Pb2+, Cd2+, and Cu2+).Furthermore, some of the Pd(II) and Pt(II) complexes were studied as potential anti-carcinogenic, with special attention to the influence of the metal complex.
124

Handheld Navigation System Implementation on FPGA Board

Salman Ali, Thamer January 2011 (has links)
The widespread use of navigation devices is increasing rapidly. This all becomes possible mainly due to increased development of hardware, for instance increased computing power (e.g. microcontroller, GPS, Compass) and software. The Handheld Navigation (HNS) is one of the navigation techniques. It is used in different fields. Just like any-other means of navigation, it is used to determine the position and direction of the user accurately and find the shortest track with precision. Global Positioning System (GPS) is a technology that can be used to determine position coordinates, time, speed and course over ground. The electronic compass is a traditional device that is used to determine the current directional angle of the user. The goal of the thesis is to compare the results of directions angle and distance from two designs (direction’s angle and distance are calculated based upon information from GPS receiver and the other direction’s angle and distance are calculated based upon information from GPS receiver and Compass). In the thesis, we have developed dual designs to achieve the goal of the thesis. The first design uses the GPS receiver coordinates to calculate the direction angle and distance, the second design integrates the GPS positioning and the digital compass, to calculate the direction and distance of Handheld Navigation user. Each device communicates with the microcontroller through the interfaces. As there are two designs. Directional results are obtained from each design. Then these results are compared with each other. After comparison, the more accurate result is chosen for the user. A Handheld Navigation PCB board design has been made. In addition SD card and LCD display are used. Both designs have been carried out on Altera Cyclone II FPGAs. The result of the prototyping shows, that the best design for Handheld Navigation System is the design that consists of GPS and Compass because the compass sensing is stable depending on the magnetic north while the previous design depends on calculated direction on movement and then also on the speed of movement. / Handhållna navigationssystem för satellitnavigering, GPS, har blivit allt vanligare. Vid navigation måste man känna till riktningen till målet men också i vilken riktning navigationsutrustningen pekar eftersom detta utgör referens för att beräkna korrigeringar. Om navigationsutrustningen rör sig med en viss hastighet så kan rörelseriktningen beräknas från ett antal på varandra följande positions- koordinater. Denna metod fungerar bra i t.ex. ett fordon som rör sig med en rimlig hastighet. Om systemet skall användas av en person som går så uppstår problem. Personen kan stanna upp och vrida runt i olika riktningar. Då finns då inga bra tidigare koordinater för att beräkna rörelseriktningen dvs. hur navigationssystemet pekar. När personen sedan rör sig i en viss riktning så måste systemet förflyttas en viss sträcka innan riktningen kan beräknas. Längden på den sträcka som krävs påverkas också av noggrannheten hos koordinatbestämningen. GPS- systemet har en icke försumbar osäkerhet på ett antal meter. Om en elektronisk kompass används för att bestämma hur navigationssystemet pekar så försvinner kravet på att systemet måste förflyttas för att kunna bestämma sin riktning. I detta examensarbete har ett GPS baserat navigationssystem utvecklats för att kunna jämföra system baserade på enbart GPS med sådana som har också en elektronisk kompass. Ett utvecklingskort för programmerbar logik har använts som plattform. Kortets FPGA-krets innehåller både processor, Nios-II soft core, och interface mot givare och minnen. Resultaten från testerna visar, inte helt oväntat, att ett system med kompass ger en säkrare navigation och en kortare väg mellan start och mål. Detta gäller främst när det finns hinder i vägen.
125

Structure and Reactivity Study of Bipyridylamino Copper and Nickel Complexes

Yang, Hui-Chuan 13 July 2004 (has links)
Late transition metal complexes bearing nitrogen-containing ligands have many applications in biotechnology or industrial catalysis. In this thesis, we react two nitrogen-containing tridentate ligands with some late transition metal salts to yield complexes (1)-(18). Besides spectroscopic characterization, complexes (3), (5)-(7), (8), (10), (12)-(16) yielded crystal structures analyzed using X-ray single crystal diffraction. From crystal structure of complexes (3), (5)- (7), we concluded that the reaction of ligand and Cu(£L£L) salts always gave the CuLX2 products. In Ni series, structures of different coordination types were obtained by using different crystal-growing methods. Crystals obtained using diffusion method take on the form of MLX2 while different structures of complexes (8), (10) were obtained using double layer method. Judging from the result of ESI-Mass analyses, complexes (8) and (10) were both of the dimeric form[NiL1Cl(£g-Cl)]2. However complex (10) was shown by X-ray single crystal to be [NiL 2(H2O)2 Cl]Cl. This could be the hydration product from [NiL1Cl(£g-Cl)]2.
126

Early stages of combustion development in internal combustion engines using linked CFD and chemical kinetics computations : illustrated by studies of a natural gas burning engine

Yossefi, Danny January 1995 (has links)
No description available.
127

Granska och värdera kvaliteten av lokala behandlingsriktlinjer med hjälp av AGREE-instrumentet

Gullin, Ann-Sofie, Magnevall, Tina January 2014 (has links)
Sammanfattning Bakgrunden beskriver hur barnmorskans arbete ska byggas på vetenskap och beprövad erfarenhet enligt gällande författningar, förordningar, föreskrifter och andra riktlinjer. Det åligger därför barnmorskan att kunna söka, analysera och kritiskt granska relevant kunskap för att kunna delta i utvecklingsarbete eller dess utvärdering. Det finns ett värde i att reflektera över befintliga rutiner och vid behov medverka till en förändring samt implementera ny kunskap. Kliniska riktlinjer har tagits fram för att underlätta det kliniska arbetet och det är därför viktigt att riktlinjerna innehåller evidensbaserad forskning. Syftet med studien var att granska och värdera kvaliteten av lokala behandlingsriktlinjer gällande mödrahälsovårdens basprogram. En kvantitativ metod valdes för att besvara studiens syfte där granskningsinstrumentet AGREE II användes, vilket är framtaget för att kunna bedöma kvalitén angående utvecklingsprocessen av kliniska riktlinjer inom hälso- och sjukvården.  Resultatet från aktuell studie visade att avsnittet mål och syfte innehöll stora variationer gällande hur tydligt formulerat syfte de olika kliniska riktlinjerna hade. Inom berörda intressenters delaktighet framkom bristfällig dokumentation angående vilka yrkeskategorier som varit delaktiga i processen även patienters åsikter saknades. Inom stringens i framställningen erhöll alla kliniska riktlinjer låga poäng, beskrivning av litteratursökningen samt val av metod saknades. Samtliga kliniska riktlinjer i avsnittet tydlighet och framställning saknade eller hade otydliga behandlingsalternativ. Däremot kunde huvudrekommendationerna urskiljas med lätthet i sju av 18 kliniska riktlinjer. I avsnittet tillämpbarhet saknade samtliga kliniska riktlinjer resonemang kring hälsoekonomiska frågor eller angående behovet av eventuella organisatoriska förändringar. Redaktionell självständighet lyftes inte fram i någon av de kliniska riktlinjerna. Ingen klinisk riktlinje fick genomgående bra poäng i helhetsbedömningen enligt AGREE II, vilket gör det svårt att rekommendera någon av de kliniska riktlinjerna utifrån dess nuvarande presentation. Med detta resultat i åtanke anser författarna att de kliniska riktlinjer som granskades i aktuell studie inte har någon påvisbar evidensbaserad grund enligt AGREE II-instrumentet och kan således inte rekommenderas att använda som stöd i det kliniska arbetet. / Abstract The work of the midwife should be based on science and knowledge according to statutes, ordinances, regulations and available guidelines. In order to participate in development work and evaluation of it, it is important for the midwife to search, analyze and critically examine the relevant knowledge. To help the nursing staff in their clinical work and to provide quality proof care to the patients, clinical guidelines have been developed. It is therefore important that the content of the clinical guidelines is based on evidence-based research and easy to understand. The aim of the study was to review and evaluate the quality of local clinical guidelines regarding the basic maternity health care program. A quantitative method was used and the clinical guidelines were reviewed using the instrument AGREE II. The findings revealed that the quality of the clinical guidelines evaluated in this study varied. The result from current study showed that the section scope and aim contained big variations regarding how clearly the purpose was formulated in the different clinical guidelines. Within the section stakeholders involvement inadequate documentations revealed, containing the occupational category the professionals who was involved in the process had, also the patients’ options were missing. Within the rigour of development all clinical guidelines gained low credits, the description of the literature search as well as the choice of method were missing. All the clinical guidelines in the section of clarity and presentation were missing or had unclear assessment alternatives. However the main recommendation could easily be distinguished in seven of the eighteen clinical guidelines. In the section of applicability all of the clinical guidelines were missing argument regarding health economics or the need of possible organizationally changes.  Editorial independence was not highlighted in any of the clinical guidelines. No clinical guideline had consistently good points according to AGREE II in the overall assessment. Therefore it is hard to recommend any of the clinical guidelines as they currently stands. With these results in mind authors of this study believes that the clinical guidelines that were viewed in this study did not, according to AGREE II, have any evidence-based ground demonstrable and can therefore not be recommended to nursing staff to be used as support in their clinical work.
128

Design and synthesis of novel AT2 receptor ligands : from peptides to drug-like molecules /

Georgsson, Jennie, January 2006 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2006. / Härtill 4 uppsatser.
129

Études sur l'inhibition pharmacologique du système rénine-angiotensine /

Fortin, Jean-Philippe. January 2003 (has links)
Thèse (M.Sc.)--Université Laval, 2003. / Bibliogr.: f. 75-93. Publié aussi en version électronique.
130

Contribution à l'étude de la réduction par l'hydrogène des solutions solides oxyde de nickel _ oxyde cuivrique.

Grange, Paul, January 1900 (has links)
Thèse--Sc. phys.--Lyon, 1970. N°: 702. / Bibliogr. p. 70-73.

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