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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

Análise socioambiental dos pescadores de lulas (Mollusca: Cephalopoda) na região de São Sebastião, Estado de São Paulo / Environmental analysis of squid fishing (Mollusca: Cephalopoda) in the region of Sao Sebastiao, State of São Paulo

Vanessa Tais Cruz Mercado 06 December 2016 (has links)
O objetivo deste estudo foi obter um diagnóstico socioambiental incluindo aspectos do etnoconhecimento dos pescadores de São Sebastião e Ilhabela (litoral norte de SP) associado à pesca de lula. Para o estudo, foram selecionados sete pontos no município de São Sebastião e dois pontos em Ilhabela. Para obtenção de dados, foi aplicado um questionário semiestruturado, contendo perguntas sobre condições socioeconômicas, infraestrutura comunitária e individual, etnoconhecimento, custos da pesca e primeira comercialização, assim como a origem da arte de pesca. As respostas foram divididas em dados qualitativos e quantitativos. Posteriormente, os dados qualitativos foram pontuados como dados quantitativos para a análise de correlação não paramétrica e de agrupamento. Aspectos históricos sobre o surgimento do zangarilho foram também explorados. Os resultados apontaram que: 1) a pesca da lula tem importância econômica, pois representa um aumento na renda do pescador; 2) não houve nenhuma correlação entre o rendimento com a pesca de lula e condições sociais ou infraestruturais; 3) a maioria dos pescadores tem idade entre 41-50 anos e, quanto ao nível escolar, a maioria possui o 10 grau incompleto e a maior parte tem emprego para complementar a renda; 4) a maior parte dos pescadores obtém em média entre R$800,00 e R$4000,00, com um ganho significativo nos meses de verão; 5) em relação à infraestrutura comunitária, foi verificada carência de acesso a escolas e hospitais; 6) a maioria dos entrevistados possui residência em São Sebastião, sendo a maior parte delas de alvenaria e com fornecimento de energia elétrica deficiente em praias mais afastadas; 7) a maioria dos pescadores considera a pesca da lula lucrativa; 8) quanto à comercialização, os melhores rendimentos são obtidos quando a venda é feita diretamente para o consumidor; 9) em termos históricos, a pesca da lula não é somente passada de pai para filho, mas também passada entre eles e amigos, tornando possível dizer que constitui um processo cultural; 10) o etnoconhecimento em relação à lula demonstrou ser significativo no que diz respeito à época de ocorrência, locais onde há fêmeas com ovas, conhecimento sobre a reprodução, sobre seus hábitos alimentares e teia alimentar. Os resultados obtidos a partir dessa pesquisa podem servir para um futuro plano de manejo. / The aim of this study was to carry out a socio environmental diagnosis which included the ethnoknowledge aspects of the fishermen from San Sebastian and Ilhabela regarding the squid fishery. We selected seven points in San Sebastian and two in Ilhabela. To obtain the data, we applied a semi-structured questionnaire covering the socioeconomic, regional infrastructure, squid sales and values, origin of the fishing skills and ethnoknowledge. The responses were initially split in qualitative and quantitative data. Afterwards, the qualitative data were scored as in quantitative parameters for cluster and non parametric correlation analysis. Historical aspects regarding the emergence of the squid jig (zangarilho) were also explored. The results showed that: 1) the squid fishery is economically important because it represents an increase to the fisherman\'s income; 2) there was no correlation between the squid fishery income and social and local infrastructure conditions 3) the majority of the fishermen community is composed of: men who are 41-50 years old; have incomplete high school degree; and work to supplement income; 4) most of the fishermen earning is about R$ 800 and R$ 4,000 with a major income in the summer; 5) the community infrastructure shows a significant lack of schools and hospitals facilities; 6) most of the fishermen live in San Sebastian, in masonry houses, and have problems regarding the electricity supply in remote beaches; 7) most of the fishermen consider squid fishing a lucrative activity; 8) the best yields are obtained when the squid is sold directly to the consumer; 9) historically, the squid fishing is handed down from father to son and among friends, which characterizes a cultural process; 10) the squid fishery ethnoknowledge shown to be significant concerning the occurrence period, places where females can be found, knowledge about feeding habits, reproduction and food web. The results obtained from this research may be useful for a future management plan.
12

Broadband DC SQUID NMR spectrometry on metals

Digby, Megan Elizabeth January 1999 (has links)
This Thesis describes the development of a broadband pulsed NMR spectrometer, based on a sensitive DC SQUID amplifier with wideband electronics, to observe directly the free precession of nuclear spins in bulk metallic samples (with broad NMR linewidths) at Larmor frequencies cß/2 ,r below 1 MHz. The sample is located inside a pickup coil, which forms a superconducting flux transformer with the input coil of the SQUID. The SQUID amplifier operates in a flux-locked-loop (FLL), hence it is sensitive to signals from DC up to the bandwidth of the FLL electronics. A modified commercial DC SQUID amplifier, with modulated feedback electronics, observed NMR signals from bulk platinum samples (T2 - 1.1 ms), at 1.5 K. The SQUID amplifier had a 50 kHz bandwidth, a dead-time - 50 μs, and a coupled energy sensitivity cc - 500h. The measurements showed that it is important to minimise the time-constant of eddy current decay in the sample, which scales with r2, as expected, where r is the sample dimension. A DC SQUID amplifier with additional positive feedback and wideband electronics configured using the direct offset integration technique, observed NMR signals from a bulk aluminium sample (T2 - 30 μs) at 20 mK. This SQUID amplifier had a 7.5 MHz bandwidth, the dead-time was 55 μs for small transmitter pulses and e,; - 600h. The use of a strongly coupled input coil with the SQUID necessitated damping across the coil to smooth out the SQUID flux-voltage characteristicThe NMR measurements showed that eddy current decay is less important if the NMR signal size is enhanced by cooling the sample. Measurements also confirmed that the NMR signal from bulk metal is proportional to 4c0, and that a reasonable estimate of the signal size is made by assuming the signal is due to spins within half the skin-depth of the surface
13

Beskrivning av vården som ges på hemodialysavdelningar utifrån registreringar med mätinstrumentet SQUID© : kan resultatet anses tillförlitligt?

Oscarsson, Ingela January 2008 (has links)
Det är väldigt få vårdtyngdsmätningsmetoder som är anpassade för hemodialysavdelningar i Sverige. Svenska Dialyssköterske Föreningen (SDF) genomförde 1996 en utvärdering av vilka metoder som används på hemodialys-avdelningarna i Sverige för att mäta vårdtyngd. Syftet var att bestämma vilken metod som var mest lämpad för mätning av vårdtyngd inom hemodialyssjukvård. Efter avslutad genomgång beslutade SDF att rekommendera SQUID©-instrumentet som metod. I arbetet med att ta fram en metod som ska används för att mäta vårdtyngd, är det viktigt att metoden anpassas till verksamheten så att de karaktäristiska patientkategorierna finns väl beskrivna i modellen. Syftet med studien var att utifrån registreringar med mätinstrumentet SQUID©, som är en vårdtyngdsmätningsmetod anpassad för hemodialyssjukvård, beskriva vilka vårdinsatser som patienterna får på 12 hemodialys-avdelningarna i Sverige och undersöka om resultatet kan anses vara tillförlitligt. Metoden har varit kvantitativ och de insamlade uppgifterna har grupperats i huvudgrupper och undergrupper och analyserats med statistiska beräkningar för att kunna skapa en bild av hur dialyssjuksköterskan noterat att hon arbetar. Resultatet från dialystillfällena har jämförts med den kompetensbeskrivning som finns för sjuksköterskor inom njursjukvård. Det visar sig i resultatet att det i stort sett råder enighet om hur instrumentet ska användas. Det finns vissa skillnader i tolkning av några rubriker och slutsatsen blir att SQUID©-instrumentet beskriver dialyssjuksköterskan arbete men det finns behov av en tydligare manual som ger mindre utrymme för egna tolkningar mellan olika avdelningar och till viss del mellan olika personal. / <p>Program: Fristående kurs</p><p>Uppsatsnivå: C</p>
14

SQUID (secure quality in dialysis) : Statisk prövning av ett instrument

Oscarsson, Ingela January 2008 (has links)
Sjukvården är idag utsatt för många organisationsförändringar och effektiviseringar. Tillgängliga resurser ska utnyttjas på bästa sätt samtidigt som kvaliteten ska upprätthållas. Vården behöver då metoder och instrument för att kunna följa upp verksamheten. Dessa instrument ska ge en beskrivning av vilka resurser de olika enheterna behöver för att kunna ge rätt sorts vård och samtidigt vara kostnadseffektiv. Det finns olika instrument och metoder för att samla in fakta och analysera data, som kan ge en fingervisning om hur mycket personal och vilken organisation som bäst gynnar vården. SQUID-instrumentet är ytterligare ett sådant instrument som kan användas för att redovisa fakta om hur mycket vård patienterna får. Metoden som SQUID är uppbyggd på utgår från att man mäter tiden för de vårdhandlingar som man utför för patienten. Instrumentet är i denna version anpassad för hemodialysavdelningar. Syftet med uppsatsen är att pröva validitet och reliabilitet för instrumentet. Prövningen har utförts genom att samla in ett referensmaterial med hjälp av Delhi-metoden från två hemodialysavdelningar. Personalen vid dessa enheter fick i uppgift att ge en beskrivning av sina arbetsuppgifter samt att uppskatta vilken tidsåtgång arbetsuppgifterna tar. Detta resultat har sedan jämförts med insamlat material från två andra hemodialysavdelningar som har använt SQUID-instrumentet. Båda metoderna redovisade på så sätt arbetsuppgifter som förekommer på hemodialysavdelningar samt vilken tidsåtgång som oftast är förknippad med dessa arbetsuppgifter. Material har sedan bearbetats med hjälp av enklare statiska beräkningar. Resultatet visar på att SQUID- instrumentet mäter det som det är avsett att mäta samt att det har en god reliabilitet. / <p>Program: Fristående kurs</p><p>Uppsatsnivå: D</p>
15

Magnetic properties of two-dimensional materials : graphene, its derivatives and molybdenum disulfide

Tsai, I-Ling January 2014 (has links)
Graphene, an atomically thin material consisting of a hexagonal, highly packed carbon lattice, is of great interests in its magnetic properties. These interests can be categorized in several fields: graphene-based magnetic materials and their applications, large diamagnetism of graphene, and the heterostructures of graphene and other two dimensional materials. In the first aspect, magnetic moments can be in theory introduced to graphene by minimizing its size or introducing structural defects, leading to a very light magnetic material. Furthermore, weak spin-orbital interaction, and long spin relaxation length make graphene promising for spintronics. The first part of this thesis addressed our experimental investigation in defect-induced magnetism of graphene. Non-interacted spins of graphene have been observed by intentionally introducing vacancies and adatoms through ion-irradiation and fluorination, respectively. The defect concentration or the magnetic moments introduced in this thesis cannot provide enough interaction for magnetic coupling. Furthermore, the spins induced by vacancies and adatoms can be controlled through shifting the Fermi energy of graphene using molecular doping, where the adatoms were alternatively introduced by annealing in the inert environment. The paramagnetic responses in graphene induced by vacancy-type defects can only be diverted to half of its maximum, while those induced by sp3 defects can be almost completely suppressed. This difference is supposed that vacancy-type defects induced two localized states (pie and sigma). Only the latter states, which is also the only states induced by sp3 defects, involves in the suppression of magnetic moments at the maximum doping achieved in this thesis. The observation through high resolution transmission electron microscope (HR-TEM) provides more information to the hypothesis of the previous magnetic findings. Reconstructed single vacancy is the majority of defects discovered in proton-irradiated graphene. This result verifies the defect-induced magnetic findings in our results, as well as the electronic properties of defected graphene in the literatures. On the other hand, the diamagnetic susceptibility of neutral graphene is suggested to be larger than that of graphite, and vanish rapidly as a delta-like function when graphene is doped. In our result, surprisingly, the diamagnetic susceptibility varies little when the Fermi level is less than 0.3 eV, in contrast with the theory. When the Fermi energy is higher than 0.3 eV, susceptibility then reduces significantly as the trend of graphite. The little variation in susceptibility near the Dirac point is probably attributed to the spatial confinement of graphene nanoflakes, which are the composition of graphene laminates. In the end of this thesis, we discuss the magnetic properties in one of the other two dimensional materials, molybdenum disulfide (MoS2). It is a potential material for graphene-based heterostructure applications. The magnetic moments in MoS2 are shown to be induced by either edges or vacancies, which are introduced by sonication or proton-irradiation, respectively, similar to the suggestions by theories. However, no significant ferromagnetic finding has been found in all of our cases.
16

Conceptual tools for managing two Monterey Bay fisheries

Ish, Teresa Lin. January 2003 (has links) (PDF)
Thesis (M.S.)--University of California, Santa Cruz, 2003. / Includes bibliographical references (leaves 71-77)
17

Nonlinear dynamics of Josephson Junction Chains and Superconducting Resonators

Ergül, Adem January 2013 (has links)
This thesis presents the results of the experimental studies on two kindof Superconducting circuits: one-dimensional Josephson junction chains andsuperconducting coplanar waveguide (CPW) resonators. One-dimensionalJosephson junction chains are constructed by connecting many Superconducting quantum interference devices (SQUIDs) in series. We have studied DC transport properties of the SQUID chains and model their nonlineardynamics with Thermally Activated Phase-Slips (TAPS). Experimental andsimulated results showed qualitative agreement revealing the existence of auniform phase-slipping and phase-sticking process which results in a voltage-independent current on the dissipative branch of the current-voltage char-acteristics (IVC). By modulating the effective Josephson coupling energy ofthe SQUIDs (EJ ) with an external magnetic field, we found that the ratio EJ /EC is a decisive factor in determining the qualitative shape of theIVC. A quantum phase transition between incoherent Quantum Phase Slip, QPS (supercurrent branch with a finite slope) to coherent QPS (IVC withwell-developed Coulomb blockade) via an intermediate state (supercurrentbranch with a remnant of Coulomb blockade) is observed as the EJ /EC ratio is tuned. This transition from incoherent QPS to the intermediate-statehappens around R0 ∼ RQ (RQ = h/4e^2 = 6.45kΩ). We also fabricated structured chains where a SQUID at the middle of the chain (central SQUID) has different junction size and loop area compared to other SQUIDs in the chain. Results showed that with these structured chains it is possible to localize andtune the amplitude of both TAPS and QPS at the central SQUID. The second part of the thesis describes the fabrication process and themeasurement results of superconducting CPW resonators. Resonators withdifferent design parameters were fabricated and measured. The transmissionspectra showed quality factors up to, Q ∼ 5 × 10^5 . We have observed bendingof the resonance curves to the lower frequencies due to existence of a nonlinear kinetic inductance. The origin of the nonlinear kinetic inductance isthe nonlinear relation between supercurrent density, Js, and superfluid veloc-ity, vs , of the charge carriers on the center line of the resonators. A simplemodel based on the Ginzburg-Landau theory is used in order to explain ob-served nonlinear kinetic inductance and estimates using this model showedgood agreement with the experimental results. / <p>QC 20131030</p> / SCOPE
18

Quantum Entanglement and Superconducting Qubits / Kvantmekanisk sammanflätning och supraledande qubits

Tang, Wai Ho January 2014 (has links)
Conventional computing based on classical technologies is approaching its limits. Therefore scientists are starting to consider the applications of quantum mechanics as a means for constructing more powerful computers. After proposing theoretical methods, many experimental setups have been designed to achieve quantum computing in reality. This thesis gives some background information on the subject of quantum computing. We first review the concept of quantum entanglement, which plays a key role in quantum computing, and then we discuss the physics of the SQUIDs-cavity method proposed by Yang et al., and give the definitions of quantum gates which are the elements that are needed to construct quantum circuits. Finally we give an overview of recent developments of SQUIDs-cavity systems and quantum circuits after Yang et al.'s proposal in 2003. These new developments help to take a step towards the constructions of higher levels of quantum technologies, e.g. quantum algorithms and quantum circuits.
19

Statistical Analysis of Species Level Phylogenetic Trees

Ferguson, Meg Elizabeth 14 November 2017 (has links)
No description available.
20

Desenvolvimento em um biogradiômetro multicanal supercondutor com SQUIDs DC para registro de medidas de magnetocardiografia fetal / Development of a Superconductor Multichannel Biogradiometer with SQUIDs DC for use in FoetalMagnetocardiography. Dissertation(Master)

Moura, Matheus Sacilotto de 26 July 2011 (has links)
Neste projeto trabalhou-se no desenvolvimento de uma nova instrumentação para registrar medidas de campos magnéticos de origem biológica baseados em sensores SQUID e sistemas auxiliares, com o objetivo de usar este arranjo na aquisição de medidas de magnetocardiografia fetal (MCGf), que consiste no registro dos campos magnéticos gerados pela atividade cardíaca fetal, refletindo seus processos eletrofisiológicos. Esta técnica biomagnética além de ser bastante precisa para obter medidas de campo magnético originado do coração fetal, que é da ordem de dez picoteslas a poucos centímetros de distância do abdômen materno, também realiza medidas de forma não-invasiva, o que a torna bastante promissora. Contudo, não se conseguiu a sensibilidade desejada do sistema biogradiométrico, sendo alcançada uma sensibilidade capaz de detectar o sinal magneto-cardiográfico (MCG) de um sistema cardíaco desenvolvido, que é da ordem de 100 pT. Neste trabalho reuniu-se, ainda, toda a informação obtida pelo grupo de biomagnetismo no decorrer dos últimos anos referente ao sistema biogradiométrico multicanal. / In this project we worked in the developing of a new instrumentation for mea- sure magnetic fields of biological source based in SQUID sensors and auxiliares systems, with aim of use this suite in measures of fetal magnetocardiography (fMCG), that is the recording of the magnetic fields generated by the fetal heart's activity, reflecting the electrophysiological processes that happen in it. This biomagnetic technique besides to be accurate enough to obtain measures of the magnetic field originated from the fetal heart, that is of the order of ten picoteslas at a few centimeters distance from the maternal abdomen, also realizes measures in outside sections at the mother's body turning it so promise. However, not obtained the desired sensitivity of the biogradiometer system, achieving just a sensitivity capable of detecting the magnetocardiography (MCG) signal of a developed cardiac system, which is about 100 pT. This work has met, yet, all information obtained by the biomagnetism group over the past years referent to the multichannel biogradiometer system.

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