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Biology of pre- and post-hatching stages of Loligo vulgaris Lamarck, 1798 and Loligo forbesi Steenstrup, 1856 (Mollusca, Cephalopoda)Martins, Maria Clara Prata Ribeiro January 1997 (has links)
Loligo vulgaris and Loligo forbesi (Cephalopoda, Myopsida) are sympatric in geographical distribution. Samples of Loligo vulgaris and Loligo forbesi eggs were collected in the two geographical areas where each species occurs predominantly, southern coast of Portugal and northwestern coast of Scotland, respectively. The embryos and hatchlings were reared in the laboratory at several experimental temperatures. This study presents new information on various aspects of the early life stages of Loligo sp. The spawned egg clusters of both species had similar external appearance. The egg strings of Loligo vulgaris are smaller and contain more eggs of smaller volume than those of Loligo forbesi. Temperature appears to be the factor limiting the distribution of these species. The percentage of deformed embryos was higher in Loligo vulgaris acclimated to lower temperature levels (13°C). The duration of the embryonic development was shortened with increasing temperature, and at similar temperature level the difference in the embryonic phase of Loligo vulgaris and Loligo forbesi was approximately 200 day-degrees. The normal hatching period from one egg string was 3 to 4 hours for both species at all experimental temperature levels. Starved Loligo vulgaris hatchlings survived longer than starved Loligo forbesi hatchlings. Maximum survival rates in Loligo vulgaris fed ad libitum were associated to the presence of live zooplankton and lower hatchling density in rearing tanks. At late embryonic stages the activity of the chorionated embryos increases in response to mechanical disturbance and to changes of light intensity. In undisturbed embryos the rate of mantle contractions increases towards pre-hatching stages. In artificial rearing condition, Loligo forbesi and Loligo vulgaris hatchlings exhibit positive phototaxis, swim at 2-3 mantle contractions per second and at relative velocities varying between 20-130 dorsal mantle lengths per second. The cost of sustained swimming was estimated between 0.02-0.06 J h-1, and the cost of transport for 7 mg hatchling was 4-12 J g-1 m-1.
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Oceanographic influences on the Illex argentinus (Cephalopoda: Ommastrephidae) fishery, Southwest AtlanticWaluda, Claire Marie January 2000 (has links)
In this study, environmental and fishery data are used to examine links between the oceanography of the Southwest Atlantic, and the distribution and abundance of the ommastrephid squid <I>Illex argentinus</I>. Spatial and temporal patterns in squid distribution and abundance are examined using Geographic Information Systems (GIS), remotely-sensed satellite-derived environmental data and statistical techniques. Inter-annual variability in the recruitment of <I>I. argentinus</I> was shown to be influenced by both large and mesoscale oceanographic processes operating during the early life history stages at the Brazil-Falkland (Malvinas) confluence. During the fishery period, in Falkland Islands (Malvinas) waters, variability in large scale sea surface temperature (SST) was not found to influence the abundance of <I>I. argentinus</I>, but the distribution of squid within the fishery was found to be associated with mesoscale oceanographic features occurring in this region. Indices describing oceanographic variability during the early life-stages were found to be of value in predicting the recruitment of squid to the fishery in Falkland Islands (Malvinas) waters. Teleconnections were shown to exist between SST anomalies in the Pacific (related to El Nino-Southern Oscillation (ENSO) events) and the Atlantic, and it is possible that environmentally-driven recruitment variability in squid populations such as <I>I. argentinus </I>may prove to be a useful biological indicator of global phenomena such as ENSO. Oceanographic variability was found to be an important factor in influencing both the distribution and abundance of <I>I. argentinus </I>in the Southwest Atlantic. The techniques used in this study are readily transferable to the study of other ommastrephid squid species.
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Gradiômetros supercondutores acoplados a SQUIDs e sua aplicação em biomagnetismo. / SQUID superconducting gradiometers applied to biomagnetism.Bruno, Antonio Carlos Oliveira 13 September 1990 (has links)
O objetivo desta tese foi o estudo da detecção de campos magnéticos fracos através da utilização de gradiômetros supercondutores acoplados à SQUIDs e sua aplicação ao biomagnetismo. Um novo modelo teórico para descrição do gradiômetro foi desenvolvido com a obtenção da sua função de transferência espacial. Através desta função de transferência a atuação do gradiômetro sobre os sinais detectados pode ser quantificada. Além disso, foi desenvolvido para a medida experimental da função de transferência, onde as imperfeições no processo de construção do sensor podem ser medidas e avaliadas. Foi proposta uma nova terminologia para descrição do gradiômetro ao invés de sua descrição física. Nesta terminologia, o gradiômetro ficará especificado pelo seu roll off, freqüência de corte espacial e ganho máximo. Também foi generalizado o método para projeto de gradiômetros onde novas configurações podem ser construídas e testadas. A partir da obtenção desta função de transferência um método para calibração tesla /volt do sistema foi desenvolvido, com uma precisão até então não alcançada por outros métodos e perfeitamente apropriado para utilização em sistemas multicanais. Finalmente foi desenvolvido um algorítimo de desconvolução para, a partir de sinais detectados com gradiômetros planares, recuperar o sinal original como ele tivesse sido detectado somente por uma bobina. Este algorítmo também pode ser utilizado para auxílio no projeto de arrays destes gradiômetros. / The objective of this thesis was to study the detection of weak magnetic fields through the use of superconducting gradiometers coupled to SQUIDs and its application to biomagnetism. A new theoretical model for the specification of the gradiometer was developed by obtaining its spatial transfer function. Through the transfer function the signal detected by the gradiometer can be quantified. Besides, a procedure was developed to experimentally measure the spatial transfer, where the imperfections in the construction process of the sensor can be measured and evaluated. A new terminology was proposed for specification of the gradiometer instead of his physical description. Using this terminology, the gradiometer will be specified by its roll off, spatial cutoff frequency and maximum gain. Also the method was generalized for design of gradiometers where new configurations can be built and tested. From the transfer function a method for tesla/volt calibration of the system was developed. Finally a deconvolution algorithm was developed, that from signals detected by the gradiometer the original signal can be recovered. This algorithm also can be used in the design of gradiometer arrays.
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Gradiômetros supercondutores acoplados a SQUIDs e sua aplicação em biomagnetismo. / SQUID superconducting gradiometers applied to biomagnetism.Antonio Carlos Oliveira Bruno 13 September 1990 (has links)
O objetivo desta tese foi o estudo da detecção de campos magnéticos fracos através da utilização de gradiômetros supercondutores acoplados à SQUIDs e sua aplicação ao biomagnetismo. Um novo modelo teórico para descrição do gradiômetro foi desenvolvido com a obtenção da sua função de transferência espacial. Através desta função de transferência a atuação do gradiômetro sobre os sinais detectados pode ser quantificada. Além disso, foi desenvolvido para a medida experimental da função de transferência, onde as imperfeições no processo de construção do sensor podem ser medidas e avaliadas. Foi proposta uma nova terminologia para descrição do gradiômetro ao invés de sua descrição física. Nesta terminologia, o gradiômetro ficará especificado pelo seu roll off, freqüência de corte espacial e ganho máximo. Também foi generalizado o método para projeto de gradiômetros onde novas configurações podem ser construídas e testadas. A partir da obtenção desta função de transferência um método para calibração tesla /volt do sistema foi desenvolvido, com uma precisão até então não alcançada por outros métodos e perfeitamente apropriado para utilização em sistemas multicanais. Finalmente foi desenvolvido um algorítimo de desconvolução para, a partir de sinais detectados com gradiômetros planares, recuperar o sinal original como ele tivesse sido detectado somente por uma bobina. Este algorítmo também pode ser utilizado para auxílio no projeto de arrays destes gradiômetros. / The objective of this thesis was to study the detection of weak magnetic fields through the use of superconducting gradiometers coupled to SQUIDs and its application to biomagnetism. A new theoretical model for the specification of the gradiometer was developed by obtaining its spatial transfer function. Through the transfer function the signal detected by the gradiometer can be quantified. Besides, a procedure was developed to experimentally measure the spatial transfer, where the imperfections in the construction process of the sensor can be measured and evaluated. A new terminology was proposed for specification of the gradiometer instead of his physical description. Using this terminology, the gradiometer will be specified by its roll off, spatial cutoff frequency and maximum gain. Also the method was generalized for design of gradiometers where new configurations can be built and tested. From the transfer function a method for tesla/volt calibration of the system was developed. Finally a deconvolution algorithm was developed, that from signals detected by the gradiometer the original signal can be recovered. This algorithm also can be used in the design of gradiometer arrays.
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Oxygen uptake by the gills and skin of cephalopodsMadan, Jeannie Jamshed January 1995 (has links)
No description available.
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Studies on the spinal reflex in an isolated mammalian preparationKelly, M. E. M. January 1984 (has links)
No description available.
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Population biology and fishery of squid and cuttlefish in the Alas Strait, IndonesiaGhofar, Abdul January 1989 (has links)
No description available.
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The Impact on Squid Export Price through Packaging Weight Standardization from Taiwanese Jigging VesselLei, Tsu-kang 02 August 2010 (has links)
Abstract
In 1972, Taiwan¡¦s first squid jigging vessel ¡§YUNG CHUNG¡¨ succeeded in developing fishing ground at Sea of Japan. Since that time, Taiwanese squid jigging vessels keep succeeding in developing new Squid fishing grounds in New Zealand, North Pacific Ocean, and Southwest of the Atlantic Ocean.
Because the squid catch continued to grow, Taiwan began to export squid products to China, Japan, South Korea, North America, and Europe.
In volumes, the top three countries of catching squids are Taiwan, China and South Korea vessels at present. However, in reality, even the freezing ability and catching quality of Taiwanese jigging vessels are much better than the other two countries, the export price for Taiwanese catch are the lowest.
The major factor is because the packaging weight has not been standardized. It reduces the purchase willingness and the selling price in the overseas markets for Taiwanese catches.
Currently, Taiwan now has 105 squid jigging vessels, but each vessel process the catch in their own way. Therefore, it makes the crew difficult to follow the work procedures which influence the efficiency, and result in inconsistent of the packaging weight.
This research we use ¡§Analytical Hierarchy Process¡¨. Through consulting with the experts and studying based from the historical documents, we try to establish the key factors on the construction and design of our questionnaire.
We then collect the answers from the fishery companies in Taiwan and sea food processing factories in China, and then we confirm the results trough the statistical analysis.
We hope through a dependable data and solid research, we can provide concrete recommendations to squid fishery companies, processing factories, and Fisheries Agency of the Government on benefits of packaging weight standardization. We then hope that the ultimate goal is to help raise the Taiwanese squid price in overseas markets.
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Etude d’une tête de réception hyperfréquence en technologie supraconductrice / Study of a radiofrequency front-end based on superconducting digital technologyCollot, Romain 02 September 2014 (has links)
Les systèmes de télécommunication de type radio logicielle ou "Software Defined Radio" (SDR) exploitent les techniques numériques qui permettent leur reconfigurabilité, que ce soit en termes de fréquence, de bande passante utilisée, ou de méthode de modulation/démodulation des signaux. Ceux-ci nécessitent des architectures permettant la numérisation des signaux analogiques RF à des fréquences d'échantillonnage de plusieurs dizaines de GHz, avec des bandes passantes de plusieurs dizaines de MHz et une résolution supérieure à 10 bits. Ces objectifs sont très difficiles à atteindre avec la technologie actuelle des semi-conducteurs. La logique à quantum de flux magnétique ou logique "Rapid Single-Flux-Quantum" (RSFQ) se présente comme un candidat séduisant pour la conception de tels systèmes.En effet, celle-ci permet d'atteindre des fréquences d'horloge de plusieurs centaines de GHz pour une consommation d'environ 100 nW par porte logique. Le travail de thèse a consisté en la réalisation d'un prototype de chaîne de réception RF analogique-numérique en technologie RSFQ. L'étude et la conception des différents blocs la constituant comme le convertisseur analogique-numérique et ceux de traitement du signal numérisé en aval a été réalisée. Les premiers résultats expérimentaux confirment la fonctionnalité des cellules RSFQ de base constituant le bloc de traitement numérique. La difficulté à faire fonctionner expérimentalement les blocs plus complexes a soulevé la question de la sensibilité des cellules RSFQ aux perturbations magnétiques extérieures. Cette problématique a été étudiée sur des circuits RSFQ simples et a permis de conclure qu'un champ magnétique externe de quelques dizaines de $mu$T était suffisant pour dégrader le fonctionnement de tels circuits. Une solution de prise en compte des effets d'un champ magnétique externe dans le simulateur utilisé a été développée pour anticiper ces problèmes dès la conception. Celle-ci a été validée expérimentalement avec un Superconducting Quantum Interference Device (SQUID). / Information and telecommunication Software Defined Radio (SDR) systems are mainly based on digital techniques, which enable to easily reconfigure them, in terms of frequency, bandwidth and modulation techniques. They can process the information entirely in a digital way, by directly sampling the input RF signal and require analog-to-digital converters with strong performances. Indeed, SDR systems have to work at sampling frequencies of several tens of GHz, with large bandwidths and a suitable resolution ($geq$ 10 bits). Rapid-Single-Flux-Quantum logic (RSFQ) seems to be an interesting solution to design such systems. This technology can reach clock frequencies of several hundreds of GHz with a power consumption of only 100 nW per logic gate. This work deals with the design of a superconductive RF front-end receiver based on RSFQ technology. The study of the different parts of the chain was done, such as the analog-to-digital converter and the signal processing part of the digital signal. Experimental results confirm that all simple RSFQ cells work with correct margins. Complex circuits work with more difficulty, raising the issue of the sensitivity of RSFQ cells to external magnetic disturbances. This point was studied on basic RSFQ cicuits and shows that a magnetic field of about 10 $mu$T is sufficient to spoil the operation of the circuit. Moreover, a solution to take into account magnetic effects in the simulation of the circuits was developed and experimentally validated on a Superconducting Quantum Interference Device (SQUID).
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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 PauloMercado, Vanessa Tais Cruz 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.
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