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991.
Koichi Takaki Kunio Sayama Atsushi Takahashi Tamiya Fujiwara Masakatsu Nagata Motoyuki Ono Muaffaq Achmad Jani 《Electrical Engineering in Japan》1999,127(4):9-17
Temperature rises of a birefringent substrate (LiNbO3) have been measured in an argon RF discharge plasma. The measurement method is based on monitoring the variation of natural birefringence with temperature by laser interferometry. Using this method, the dependence of substrate temperature rise on applied RF power and gas pressure has been investigated. The evaluation of the temperature curves shows that heat flux from the plasma toward the substrate is independent of time and temperature. The magnitude of the flux differs largely from the applied power, and is approximately 0.4% of the power. By measuring the electron density, electron temperature, and plasma potential with a Langmuir probe, the energy of the ions incident on the substrate is estimated. The ion flux toward the substrate is calculated from the energy of ions and is compared with the measured heat flux. The dependence on the applied power is in approximate agreement between those fluxes. The temperature distribution over the substrate thickness is simulated numerically using the finite difference method. © 1999 Scripta Technica, Electr Eng Jpn, 127(4): 9–17, 1999 相似文献
992.
Keiichiro Tojo Minoru Kurosawa Koichi Oka Toshiro Higuchi 《Electrical Engineering in Japan》1999,128(4):94-101
The application of single‐bit digital signal processing to mechanical control systems has already been proposed by the authors. Multibit A/D converters have been improved to a high level. But it is difficult to improve high‐resolution A/D by the latest semiconductor technologies. A single‐bit digital signal can be generated by a delta‐sigma modulator. Single‐bit digital signal has a small quantized error at low frequency. Then with this single‐bit digital signal processing, high resolution on controlling such a narrow‐bandwidth mechanical system will be realized. In this paper, resolution of analog, multibit, and single‐bit control systems is estimated via simulation. According to the results of simulations, a single‐bit control system has a higher resolution than a multibit system under conditions of equal bit rates. © 1999 Scripta Technica, Electr Eng Jpn, 128(4): 94–101, 1999 相似文献
993.
Kazuhiko Kato Akinobu Murata Koichi Sakuta 《Progress in Photovoltaics: Research and Applications》1998,6(2):105-115
The concerns about environmental impacts of photovoltaic (PV) power systems are growing with the increasing expectation of PV technologies. In this paper, three kinds of silicon-based PV modules, namely single-crystalline silicon (c-Si), polycrystalline silicon (poly-Si) and amorphous silicon (a-Si) PV modules, are evaluated from the viewpoint of their life-cycle. For the c-Si PV module it was assumed that off-grade silicon from semiconductor industries is used with existing production technologies. On the other hand, new technologies and the growth of production scale were presumed with respect to the poly-Si and a-Si PV modules. Our results show that c-Si PV modules have a shorter energy pay-back time than their expected lifetime and lower CO2 emission than the average CO2 emission calculated from the recent energy mix in Japan, even with present technologies. Furthermore the poly-Si and the a-Si PV modules with the near-future technologies give much reduction in energy pay-back times and CO2 emissions compared with the present c-Si PV modules. The reduction of glass use and the frameless design of the PV module may be effective means to decrease them more, although the lifetime of the PV module must be taken into account. © 1998 John Wiley & Sons, Ltd. 相似文献
994.
This paper proposes a new concept of an electric power delivery system for future decades. The power delivery network consists of a set of meshed networks spread over every demand-side block (city or town). On the end point of the power line network, quality improvement facilities (referred to as “quality improvement centers”) are installed, and each consumer can select an arbitrary quality of electricity. Thus the system can achieve multi-menu-services and uninterrupted power supply. The system contains small-scale energy storage and dispersed small-scale power generation systems. The main circuit breakers consist of power electronics devices, and communication networks are fully installed so as to control the power electronics devices or power flow according to system situations or the fault situations. The communication network also controls the demand-side management. From the above, the proposed power delivery network is flexible and reliable. The intelligent facilities (computers) are installed in the control centers as well as in the quality improvement centers. They keep the system as the most energy-conservative form. In this paper, the system is named FRIENDS (Flexible, Reliable and Intelligent Electrical eNergy Delivery system). The conclusion of this paper summarizes the major research areas that must be completed to realize the system. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 121(1): 26–34, 1997 相似文献
995.
996.
An approach based on the finite element method (FEM) with the rectangular-parallelepipd edge element is proposed for the analysis of electromagnetic waveguide bends. Here, to be permissible for analysis of various electromagnetic waveguides, the analytical relations in the uniform waveguide are constructed numerically by using the FEM with the rectangular edge element. To confirm the validity and versatility of this approach, bends of a hollow waveguide, a half-filled dielectric waveguide, and a finline are analyzed. © 1996 John Wiley & Sons, Inc. 相似文献
997.
Ryo Koyama Koichi Iwata Yoshinori Hayashi Suzuro Hitomi Ikuko Shibuta Akihiko Furukawa Sayaka Asano Tadayoshi Kaneko Yoshiyuki Yonehara Masamichi Shinoda 《International journal of molecular sciences》2021,22(21)
Pain is one of the most severe concerns in tongue cancer patients. However, the underlying mechanisms of tongue cancer pain are not fully understood. We investigated the molecular mechanisms of tongue cancer-induced mechanical allodynia in the tongue by squamous cell carcinoma (SCC) inoculation in rats. The head-withdrawal threshold of mechanical stimulation (MHWT) to the tongue was reduced following SCC inoculation, which was inhibited by intracisternal administration of 10Panx, an inhibitory peptide for pannexin 1 (PANX1) channels. Immunohistochemical analyses revealed that the expression of PANX1 was upregulated in the trigeminal spinal subnucleus caudalis (Vc) following SCC inoculation. The majority of PANX1 immunofluorescence was merged with ionized calcium-binding adapter molecule 1 (Iba1) fluorescence and a part of it was merged with glial fibrillary acidic protein (GFAP) fluorescence. Spike frequencies of Vc nociceptive neurons to noxious mechanical stimulation were significantly enhanced in SCC-inoculated rats, which was suppressed by intracisternal 10Panx administration. Phosphorylated extracellular signal-regulated kinase (pERK)-immunoreactive (IR) neurons increased significantly in the Vc after SCC inoculation, which was inhibited by intracisternal 10Panx administration. SCC inoculation-induced MHWT reduction and increased pERK-IR Vc neuron numbers were inhibited by P2X7 purinoceptor (P2X7R) antagonism. Conversely, these effects were observed in the presence of P2X7R agonist in SCC-inoculated rats with PANX1 inhibition. SCC inoculation-induced MHWT reduction was significantly recovered by intracisternal interleukin-1 receptor antagonist administration. These observations suggest that SCC inoculation causes PANX1 upregulation in Vc microglia and adenosine triphosphate released through PANX1 sensitizes nociceptive neurons in the Vc, resulting in tongue cancer pain. 相似文献
998.
Go Yoshida Hiroshi Matsumura Koichi Nishikawa Akihiro Toyoda Yoshiharu Miyazaki Kazuyoshi Masumoto Hajime Nakamura Taichi Miura 《辐射防护》2020,40(6):545-549
The assessment of activated concrete is particularly difficult during the decommissioning of an accelerator facility.Destructive analysis by core boring is the only method of investigating the activity of concrete material.To address this problem,an in-situ and nondestructive analysis method was developed to determine γ-ray-emitting nuclides and their specific activities in the concrete walls and floor by using a portable germanium semiconductor detector.In this work,we examined a substitute for... 相似文献
999.
Koichi Fujisawa Taro Takami Shoki Okubo Yuto Nishimura Yusaku Yamada Keisuke Kondo Toshihiko Matsumoto Naoki Yamamoto Isao Sakaida 《International journal of molecular sciences》2021,22(18)
Among lifestyle-related diseases, fatty liver is the most common liver disease. To date, mammalian models have been used to develop methods for inhibiting fatty liver progression; however, new, more efficient models are expected. This study investigated the creation of a new model to produce fatty liver more efficiently than the high-fat diet medaka model that has been used to date. We compared the GAN (Gubra-Amylin nonalcoholic steatohepatitis) diet, which has been used in recent years to induce fatty liver in mice, and the high-fat diet (HFD). Following administration of the diets for three months, enlarged livers and pronounced fat accumulation was noted. The GAN group had large fat vacuoles and lesions, including ballooning, compared to the HFD group. The GAN group had a higher incidence of lesions. When fenofibrate was administered to the fatty liver model created via GAN administration and liver steatosis was assessed, a reduction in liver fat deposition was observed, and this model was shown to be useful in drug evaluations involving fatty liver. The medaka fatty liver model administered with GAN will be useful in future fatty liver research. 相似文献
1000.
共沉淀法制备Al_2O_3-YAG复相陶瓷及其显微结构研究 总被引:1,自引:0,他引:1
用共沉淀法制备了Al2O3-YAG复合粉体,YAG的结晶温度在1000℃左右.共沉淀法 制备的Al2O3-YAG复合粉体经1550℃热压烧结,获得致密烧结体,YAG的加入量对烧结温度 的影响不大. Al2O3-5vol%YAG复合材料的抗弯强度为604MPa,断裂韧性为5.0MPam1/2; Al2O3-25vol%YAG复合材料的抗弯强度为611MPa,断裂韧性为45MPam1/2.所有这些数据 都高于单相Al2O3陶瓷的力学性能,说明YAG的加入有利于A12O3陶瓷力学性能的提高. 通过显微结构观察发现:大的YAG颗粒位于Al2O3晶界上,小的YAG颗粒位于Al2O3晶粒 内.在 Al2O3-5vol%YAG复合材料中,许多小的白色区域存在于 Al2O3晶粒内,这可能和较低 的Y2O3含量有关. 相似文献