2,313 research outputs found

    Simultaneous Measurement for Strain and Temperature Using Fiber Bragg Gratings and Multimode Fibers

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    An all-fiber sensor capable of simultaneous measurement of temperature and strain is newly presented. The sensing head is formed by a fiber Bragg grating combined with a section of multimode fiber that acts as a Mach-Zehnder interferometer for temperature and strain discrimination. The strain and temperature coefficients of multimode fibers vary with the core sizes and materials. This feature can be used to improve the strain and temperature resolution by suitably choosing the multimode fiber. For a 10 pm wavelength resolution, a resolution of 9.21 Ό∈ in strain and 0.26°C in temperature can be achieved

    Core-Offset Small-Core-Diameter Dispersion Compensation Fiber Interferometer and its Applications in Fiber Sensors

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    We propose a core-offset small core diameter dispersion compensation fiber (DCF) interferometer and investigate its applications in fiber sensors. If the transverse force is applied to a short section of the DCF, there is almost no crosstalk on the transmission spectrum between the extinction ratio variation induced by the transverse force and the wavelength shift caused by the longitudinal strain or ambient temperature, which can be applied to measure both transverse and longitudinal strain, or both transverse strain and temperature, simultaneously. The proposed sensors have the advantages of low cost, simple and compact structure, and good reproducibility

    Temperature- and Phase-Independent Lateral Force Sensor based on a Core-Offset Multi-Mode Fiber Interferometer

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    A novel lateral force sensor based on a core-offset multi-mode fiber (MMF) interferometer is reported. High extinction ratio can be obtained by misaligning a fused cross section between the single-mode fiber (SMF) and MMF. With the variation of the lateral force applied to a short section of the MMF, the extinction ratio changes while the interference phase remains almost constant. The change of the extinction ratio is independent of temperature variations. The proposed force sensor has the advantages of temperature- and phase-independency, high extinction ratio sensitivity, good repeatability, low cost, and simple structure. Moreover, the core-offset MMF interferometer is expected to have applications in fiber filters and tunable phase-independent attenuators

    ConteĂșdo e bioconversĂŁo de isoflavonas ÎČ‑glicosĂ­deos em agliconas nas condiçÔes de processamento do tempeh de soja

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    The objective of this work was to evaluate the effect of the processing conditions of soybean tempeh on the contents of ÎČ‑glycoside isoflavones and on their bioconversion into aglycones. Different times of soaking (6, 12, and 18 hours), cooking (15, 30, and 45 minutes), and fermentation (18, 24, and 30 hours) with Rhizopus oligosporus at 37°C were evaluated for tempeh preparation. Grains from the cultivar 'BRS 267' were used, and the experiment was carried out according to a central composite design (23). The response functions comprised the contents of genistin, malonyldaidzin, malonylgenistin, daidzein, and genistein, quantified by ultraperformance liquid chromatography (UPLC). Soaking, cooking, and fermentation times change the content, profile, and distribution of the different forms of isoflavones in tempeh. The highest bioconversion of glycoside isoflavones into aglycones occurred in 6‑hour soaked soybean grains, whose cotyledons were cooked for 15 minutes and subjected to 18‑hour fermentation.O objetivo deste trabalho foi avaliar o efeito das condiçÔes de processamento do tempeh de soja sobre o conteĂșdo de isoflavonas ÎČ‑glicosĂ­deos e sobre sua bioconversĂŁo em agliconas. Diferentes tempos de maceração (6, 12 e 18 horas), cozimento (15, 30 e 45 minutos) e fermentação (18, 24 e 30 horas) com Rhizopus oligosporus a 37°C foram avaliados na preparação do tempeh. Foram utilizados grĂŁos da cultivar 'BRS 267', e o experimento foi realizado de acordo com um delineamento composto central (23). As funçÔes-respostas compreenderam o teor de genistina, malonildaidzina, malonilgenistina, daidzeĂ­na e genisteĂ­na, quantificadas por cromatografia lĂ­quida de ultraeficiĂȘncia (CLUE). Os tempos de maceração, cozimento e fermentação alteraram o conteĂșdo, o perfil e a distribuição das diferentes formas de isoflavonas no tempeh. A maior bioconversĂŁo de ÎČ‑glicosĂ­deos em agliconas ocorreu em grĂŁos de soja macerados por 6 horas, cujos cotilĂ©dones foram cozidos por 15 minutos e submetidos Ă  fermentação por 18 horas

    Computer-aided DSM-IV-diagnostics – acceptance, use and perceived usefulness in relation to users' learning styles

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    BACKGROUND: CDSS (computerized decision support system) for medical diagnostics have been studied for long. This study was undertaken to investigate how different preferences of Learning Styles (LS) of psychiatrists might affect acceptance, use and perceived usefulness of a CDSS for diagnostics in psychiatry. METHODS: 49 psychiatrists (specialists and non-specialists) from 3 different clinics volunteered to participate in this study and to use the CDSS to diagnose a paper-based case (based on a real patient). LS, attitudes to CDSS and complementary data were obtained via questionnaires and interviews. To facilitate the study, a special version of the CDSS was created, which automatically could log interaction details. RESULTS: The LS preferences (according to Kolb) of the 49 physicians turned out as follows: 37% were Assimilating, 31% Converging, 27% Accommodating and 6% Diverging. The CDSS under study seemed to favor psychiatrists with abstract conceptualization information perceiving mode (Assimilating and Converging learning styles). A correlation between learning styles preferences and computer skill was found. Positive attitude to computer-aided diagnostics and learning styles preferences was also found to correlate. Using the CDSS, the specialists produced only 1 correct diagnosis and the non-specialists 2 correct diagnoses (median values) as compared to the three predetermined correct diagnoses of the actual case. Only 10% had all three diagnoses correct, 41 % two correct, 47 % one correct and 2 % had no correct diagnose at all. CONCLUSION: Our results indicate that the use of CDSS does not guarantee correct diagnosis and that LS might influence the results. Future research should focus on the possibility to create systems open to individuals with different LS preferences and possibility to create CDSS adapted to the level of expertise of the user
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