1,411 research outputs found

    Simple modeling for conducted common-mode current in switching circuits

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    Common mode current strongly depends on stray capacitance of each circuit node, especially those with high dv/dt and di/dt. To build a simple model for conducted common mode current in switching circuit a computer software based on Partial Element Equivalent Circuit (PEEC) method is used to calculate the parasitic elements of the printed circuit board (PCB). Simulation results agree well with experimental results up to 10 MHz.published_or_final_versio

    Anisotropic electronic structure in quasi-one-dimensional K0.3MoO3: An angle-dependent x-ray absorption study

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    100學年度杜昭宏升等參考著作[[abstract]]The electronic structure of quasi-one-dimensional (quasi-1D) blue bronze, K0.3MoO3, was investigated by angle-dependent x-ray absorption near-edge structure (XANES) spectroscopy at O and K K and Mo L3 edges along the quasi-1D MoO6 octahedron-chain direction, i.e., the b axis, and the octahedron-in-plane direction, i.e., the d axis, well below its Peierls phase transition temperature (180 K). The O K-edge XANES spectra indicate that the angle dependence of O 2p–Mo 4d hybridization, especially those with the π* character, is more significant along the b axis than along the d axis. Similar trend is also observed in the Mo L3-edge XANES spectra. The K K-edge XANES spectra reveal anisotropic effect of hybridization of K 4p states with O 2p states on the MoO6 octahedron.[[notice]]補正完畢[[journaltype]]國外[[incitationindex]]SCI[[booktype]]紙本[[countrycodes]]US

    Enhancement of Si-O hybridization in low-temperature grown ultraviolet photo-oxided SiO2 film observed by x-ray absorption and photoemission spectroscopy

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    100學年度杜昭宏升等參考著作[[abstract]]The dielectric properties associated with the electronic and bonding structures of SiO2 films were examined using the Si L3,2- and O K-edge x-ray absorption near-edge structures (XANES) and valence-band photoemission spectroscopy (VB-PES) techniques. The Si L3,2- and O K-edge XANES measurements for the low-temperature grown UV-photon oxidized SiO2 (UV-SiO2) and the conventional high-temperature thermal-oxidized SiO2 (TH-SiO2) suggest enhancement of O 2p–Si 3p hybridization in UV-SiO2. VB-PES measurements reveal enhancement of nonbonding O 2p and O 2p–Si 3p hybridized states. The enhanced O 2p and Si 3p hybridization implies a shortening of the average Si–O bond length, which explains an increase of the density and the improvement of the dielectric property of UV-SiO2.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]紙

    Electronic and bonding structures of amorphous Si–C–N thin films by x-ray absorption spectroscopy

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    [[abstract]]X-ray absorption near edge structure (XANES) spectra of hard amorphous a-Si–C–N thin films with various compositions were measured at the C and N K-edge using sample drain current and fluorescent modes. The C K-edge XANES spectra of a-Si–C–N contain a relatively large 1s→π∗ peak, indicating that a substantial percentage of carbon atoms in the a-Si–C–N films have sp2 or graphite-like bonding. Both the observed sp2 intensity and the Young’s modulus decrease with an increase in the carbon content. For N K-edge XANES spectra of the a-Si–C–N films we find the emergence of a sharp peak near the threshold when the carbon content is larger than between 9% and 36%, which indicates that carbon and nitrogen atoms tend to form local graphitic carbon nitride.[[booktype]]紙

    Influence of Altered Serum Cholesterol Levels and Fasting on Cutaneous Cholesterol Synthesis

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    Barrier perturbation stimulates epidermal cholesterol synthesis, which plays an important role in restoring barrier function. In the present study, we examined whether changes in serum cholesterol levels or nutrition regulate epidermal cholesterol synthesis in hairless mice. Serum cholesterol levels were lowered by 50% after injection with 4- aminopyrazolo (3,4-d) pyrimidine and were increased by 51% by feeding an atherogenic diet. In contrast to most other tissues, cholesterol synthesis in the epidermis and dermis was not inhibited by elevations or stimulated by decreases in serum cholesterol levels. Additionally, feeding a high-cholesterol diet did not decrease epidermal or dermal cholesterol synthesis. However, fasting significantly decreased both epidermal (38%) and dermal (34%) cholesterologenesis. Furthermore, barrier recovery after acetone disruption of the barrier was impaired in fasted animals. However, treatment with topical lipids did not restore barrier repair rate to normal, indicating that factors in addition to lipids are necessary to overcome the effects of fasting. These results demonstrate that cholesterol synthesis in the epidermis and dermis is regulated independently of changes in serum cholesterol levels

    Firefighter Hood for Cooling by Exploring Phase Change Materials

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    The goal of PCM textiles is to create reusable energy to maintain body temperature, as well as to optimize the performance of protective wear such as gloves. Maintaining a stable body temperature can improve working conditions and comfort. The study also has practical applications for the inner linings of protective clothing in conditions of high heat or extreme temperature. Laboratory research design was used in this study to explore the application of PCM in design protective hood

    Having a family doctor is associated with some better patient-reported outcomes of primary care consultations

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    <b>Background</b> Hong Kong (HK) has pluralistic primary care that is provided by a variety of doctors. The aim of our study was to assess patient-reported outcomes of primary care consultations in HK and whether having a family doctor (FD) made any difference.<p></p> <b>Methods</b> We interviewed by telephone 3148 subjects from 5174 contacted households (response rate 60.8%) randomly selected from the general population of HK about the experience of their last primary care consultations in September 2007 and April 2008. We compared the patient-reported outcomes (PRO) and patient-centered process of care in those with a FD, those with other types of regular primary care doctors (ORD) and those without any regular primary care doctor (NRD). PRO included patient enablement, global improvement in health, overall satisfaction, and likelihood of recommending their doctors to family and friends. Patient-centered process of care indicators was explanations about the illness, and address of patient’s concerns.<p></p> <b>Results</b> One thousand one hundred fifty, 746, and 1157 reported to have FD, ORD, and NRD, respectively. Over 80% of those with FD consulted their usual primary care doctors in the last consultation compared with 27% of those with NRD. Compared with subjects having ORD or NRD, subjects with FD reported being more enabled after the consultation and were more likely to recommend their doctors to family and friends. Subjects with FD and ORD were more likely than those having NRD to report a global improvement in health and satisfaction. FD group was more likely than the other two groups to report receiving an explanation on the diagnosis, nature, and expected course of the illness, and having their concerns addressed. Patient enablement was associated with explanation of diagnosis, nature, and expected course of illness, and address of patient’s concerns.<p></p> <b>Conclusion</b> People with a regular FD were more likely to feel being enabled and to experience patient-centered care in consultations
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