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排序方式: 共有375条查询结果,搜索用时 15 毫秒
61.
Hirotami Nakano Takeshi Tanabe Masanobu Naitoh Yoshiki Kubota Tsuyoshi Morita Toyoaki Kimura Makoto Matsukawa Yushi Miura 《Electrical Engineering in Japan》2000,131(4):1-10
In a balanced three‐phase system, the three‐phase current distortion factor of three‐phase ac power sources has been expressed by applying the conventional single‐phase current distortion factor, which is defined for a single‐phase system. However, in an unbalanced three‐phase system, it is difficult to express the three‐phase current distortion factor for distorted three‐phase ac currents by means of the conventional single‐phase current distortion factor. For instance, the conventional current distortion factors for three‐phase ac currents are usually different from each other in the unbalanced three‐phase system. To solve the above problem, this paper proposes a novel definition of the three‐phase current distortion factor. The proposed three‐phase current distortion factor is quite effective for the unbalanced three‐phase system as well as the balanced three‐phase system. © 2000 Scripta Technica, Electr Eng Jpn, 131(4): 1–10, 2000 相似文献
62.
This paper describes a method for designing electromagnetically coupled (EMC) printed dipole arrays. The advantages of EMC dipoles include greater bandwidth, higher efficiency, and an easier match to the feed lines, when compared to classically fed printed antennae. The excitation mechanism is provided by a strip transmission line embedded inside the substrate which couples energy parasitically to the microstrip antenna. Electromagnetically coupled microstrip dipoles have been investigated by empirical or approximate analysis techniques. As a result an approximate model has been derived for microstrip dipoles. The method is based on the method of moments solution to an integral equation derived from the approximate Green function for a grounded dielectric slab. The element lengths and offsets and the stub length of the EMC dipole array are determined by the direct search optimization method of Hooke and Jeeves. To show the feasibility of the proposed method, a mathematical formulation and numerical results are presented for Chebyshev arrays. © 1998 Scripta Technica, Electr Eng Jpn, 125(4): 60–66, 1998 相似文献
63.
Masanobu Yoshida Toshihiro Takahashi Masayuki Hikita Hiroyuki Watanabe Naomi Hashimoto Hitoshi Okubo 《Electrical Engineering in Japan》1999,129(4):58-65
We observed current pulse waveforms of partial discharge (PD) in SF6 gas so as to investigate the PD mechanism. We also measured light intensity and light emission image of PD simultaneously under different conditions of applies voltage and SF6 gas pressure. From these experiments, we found that the “double-peak current waveform” appeared at high pressure and high voltage conditions. We also analyzed the mutual correlation of waveforms between a single current and the light emission. Moreover, we obtained experimental evidence of filmentlike light image appearing at the PD tip under the same condition with double-peak current waveform. From the electric field analysis around the needle electrode tip, we believe that the filamentlike light image expands beyond the critical electric field of SF6 gas. Thus, we concluded that these current waveforms with double peaks showed evidence of leader-type PD, leading to breakdown. Finally, we could point out that leader-type PD should be distinguished and measured for the diagnosis of GIS insulation performance. © 1999 Scripta Technica, Electr Eng Jpn, 129(4): 58–65, 1999 相似文献
64.
Yuko Kinowaki Towako Taguchi Iichiroh Onishi Susumu Kirimura Masanobu Kitagawa Kouhei Yamamoto 《International journal of molecular sciences》2021,22(17)
Ferroptosis, a term first proposed in 2012, is iron-dependent, non-apoptotic regulatory cell death induced by erastin. Ferroptosis was originally discovered during synthetic lethal screening for drugs sensitive to RAS mutant cells, and is closely related to synthetic lethality. Ferroptosis sensitizes cancer stem cells and tumors that undergo epithelial−mesenchymal transition and are resistant to anticancer drugs or targeted therapy. Therefore, ferroptosis-inducing molecules are attractive new research targets. In contrast, synthetic lethal strategies approach mechanisms and genetic abnormalities that cannot be directly targeted by conventional therapeutic strategies, such as RAS mutations, hypoxia, and abnormalities in the metabolic environment. They also target the environment and conditions specific to malignant cells, have a low toxicity to normal cells, and can be used in combination with known drugs to produce new ones. However, the concept of synthetic lethality has not been widely adopted with ferroptosis. In this review, we surveyed the literature on ferroptosis-related factors and synthetic lethality to examine the potential therapeutic targets in ferroptosis-related molecules, focusing on factors related to synthetic lethality, discovery methods, clinical application stages, and issues in drug discovery. 相似文献
65.
This paper presents a unique structural reliability estimation method incorporating structural parameter identification results based on the seismic response measurement. In the shaking table test, a three-bent concrete bridge model was shaken to different damage levels by a sequence of earthquake motions with increasing intensities. Structural parameters, stiffness and damping values of the bridge were identified under damaging seismic events based on the seismic response measurement. A methodology was developed to understand the importance of structural parameter identification in the reliability estimation. Along this line, a set of structural parameters were generated based on the Monte Carlo simulation. Each of them was assigned to the base bridge model. Then, every bridge model was analyzed using nonlinear time history analyses to obtain damage level at the specific locations. Last, reliability estimation was performed for bridges modeled with two sets of structural parameters. The first one was obtained by the nonlinear time history analysis with the Monte Carlo simulated parameters which is called nonupdated structural parameters. The second one was obtained by updating the first set in Bayesian sense based on the vibration-based identification results which is called updated structural parameters. In the scope of this paper, it was shown that residual reliability of the system estimated using the updated structural parameters is lower than the one estimated using the nonupdated structural parameters. 相似文献
66.
Xingcai Guan Masanobu Manabe Isao Murata Tieshan Wang 《Journal of Nuclear Science and Technology》2013,50(4):503-508
Boron neutron capture therapy (BNCT) is a promising cancer therapy. Epi-thermal neutron (0.5 eV < En < 10 keV) flux intensity is one of the basic characteristics for modern BNCT. In this work, based on the 71Ga(n,γ)72Ga reaction, a new simple monitor with gallium nitride (GaN) wafer as activation material was designed by Monte Carlo simulations to precisely measure the absolute integral flux intensity of epi-thermal neutrons especially for practical BNCT. In the monitor, a GaN wafer was positioned in the center of a polyethylene sphere as neutron moderator covered with cadmium (Cd) layer as thermal neutron absorber outside. The simulation results and related analysis indicated that the epi-thermal neutron flux intensity could be precisely measured by the presently designed monitor. 相似文献
67.
Yoshie Fujimori Yasuo Gotoh Akio Kawaguchi Yutaka Ohkoshi Masanobu Nagura 《应用聚合物科学杂志》2008,108(5):2814-2824
In this study, the structure and properties of an organic–inorganic composite material prepared from nylon 6 doped with fine particles of silver iodide (AgI) were examined. The preparation of the composite involved the complexation of nylon 6 with polyiodide ions such as I and I by immersion in an iodine/potassium iodide (I2–KI) aqueous solution followed by reaction in a silver nitrate (AgNO3) aqueous solution; this resulted in the in situ formation of β-AgI fine particles within the nylon 6 matrix. The AgI content formed in the composite was dependent on the immersion temperatures of the I2–KI and AgNO3 solutions. Lower solution temperatures resulted in larger amounts of AgI in the composite. This method readily provided a composite with a high content of AgI in nylon 6 and a conductivity of approximately 10−5 Ω−1 cm−1. In a uniaxially oriented nylon 6 matrix, AgI particles precipitated with anisotropic shape, which was caused by the orientation of the precursor polyiodide ions. The structure of the oriented composite provided the anisotropic conductivity. Additionally, the composite exhibited high antibacterial properties. The procedure used in this study is considered a unique method for the preparation of organic–inorganic composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
68.
In this report, we established a new electrochemical method for the detection of conformational changes in large, non-metalloproteins such as bovine serum albumin, using flow injection analysis coupled with hydrogen-terminated, boron-doped diamond electrodes. The oxidation current was used as a signal reporter in the monitoring of urea-induced BSA denaturation. In the denatured state at high urea concentrations, the electrochemical signal increased, and the amperometric responses for the oxidation potential at 1300 mV were consistent with the results of conventional methods of denaturation monitoring using fluorescence spectroscopy. The oxidation involved at least five redox-active species (cysteine, tryptophan, tyrosine, methionine, and disulfide bonds). Furthermore, the method also showed high sensitivity for quantitative analysis of protein. A linear dynamic in the concentration range 50-400 microg/mL (r(2) = 0.977) with a lower detection limit of 190 ng/mL was achieved for BSA. Direct electrochemical detection of conformation changes of proteins using BDD electrodes can be performed with advantages in terms of simplicity and sensitivity. 相似文献
69.
Jiyang Wang Masanobu Sakashita Susumu Kono Hitoshi Tanaka 《The Structural Design of Tall and Special Buildings》2012,21(9):669-681
Reinforced concrete (RC) structural walls usually have some eccentric large openings according to the intention of the architectural design. However, the behaviour of such structures that are shear critical under cyclic loading has not been well studied. In this study, three single‐span, three‐storied, 40% scale specimens of RC structural walls with various eccentric opening ratios were constructed and tested in a lateral reverse cyclic manner until severe shear damage occurred in the walls. The main purposes of these tests were to evaluate the shear behaviour and to recognize the influence of various opening ratios on cracking and shear strength of structural walls under cyclic loading. The shear strength of specimen was calculated combining the shear strength of a structural wall without openings and the reduction factor due to openings. The comparison between the experimental results and the analytical results shows that the shear strength is different depending on the loading direction due to the eccentric opening location, the span length of short span beams may affect the cracking process and the failure mode, the approximate calculation method using Ono's reduction factor could be well applied to RC structural walls with various opening ratios less than 0.46. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献