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Cooperative Control by System Voltage Control Equipments in Consideration of Reducing Capacity of STATCOM 下载免费PDF全文
Shoji Kawasaki Naohiro Kurokawa Hisao Taoka Yuya Nakashima 《Electrical Engineering in Japan》2016,194(1):1-9
In recent years, the number of renewable energy sources (RESs) such as photovoltaic generation systems and wind power generation systems connected to the grid has been increasing as a way of reducing negative effects on the environment. The outputs of these RESs vary rapidly because of the influence of the weather and the conditions of the location. Therefore, there are concerns that the point voltages in a distribution system may vary drastically and that the voltages may deviate from the appropriate voltage range as a result of the influence of the RES connected to the distribution system or to the diversification of loads. Furthermore, there are concerns about adverse effects on electric power quality, such as voltage imbalances and harmonics. In this paper, we propose a cooperative voltage control method for a distribution system using system voltage control equipment in order to reduce the capacity of the static synchronous compensator. Numerical calculations were performed in order to verify the validity of the proposed method. 相似文献
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Toru Kizaki Shinji Tsujimura Yuya Marukawa Shigeo Morimoto Hisashi Kobayashi 《CIRP Annals》2021,70(1):325-328
A novel temperature measuring system named LATSIS was proposed to realize a robust and accurate prediction of the thermal deformation of machining centers, even under external disturbances such as cutting fluid supply. LATSIS enables a drastic increase in the number of sensors employed for measuring the temperature of the machine tool. Thus, the entire temperature distribution can be obtained by interpolating the measured temperature 3-dimensionally without calculating the heat conduction. A set of experiments was conducted in which the LATSIS was employed to predict the TCP error. A total of 284 sensors were placed on the machining center, and the TCP error was predicted based on the measured temperature for the situation with/without the cutting fluid supply. The results of the prediction showed good agreement with the measured TCP error even during the initial transient temperature change as well as in the cooling phase after the machine halt. The TCP error with the cutting fluid supply is accurately predicted. LATSIS was proven to be a robust and accurate method for predicting the thermal deformation of machine tools, and is a promising technology for future manufacturing systems. 相似文献
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Jomjai Peerapattana Kuniko Otsuka Yusuke Hattori 《Drug development and industrial pharmacy》2015,41(3):515-521
The objective of this research was to quantify the α-mangostin content in mangosteen pericarp (MP) ointment as a colloidal dispersion using near-infrared (NIR) spectroscopy. Various concentrations of MP (IP and EP) ointments containing both internal and external pericarps were prepared and the NIR spectra of these ointments were measured. The NIR spectrum of each ointment was correlated with α-mangostin concentration by partial least square (PLS) regression. Validation of the models was performed and their predictive ability was also investigated. The equation and R2 value for the prediction of α-mangostin concentration in IP ointment were y?=?0.9843x?+?0.4441 and 0.9730 and those in EP ointment were y?=?0.9569x?+?0.1142 and 0.9136, respectively. The biases of the IP and EP ointment models were 0.23 and 0.00, respectively. The results showed that NIR could be a useful tool for the quality control of herbal medicine in hydrophilic ointment without any sample preparation. It could predict α-mangostin content in hydrophilic ointment at very low concentration with sufficient accuracy. 相似文献
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Ryuta Shigefuku Hideaki Takahashi Hiroyasu Nakano Tsunamasa Watanabe Kotaro Matsunaga Nobuyuki Matsumoto Masaki Kato Ryo Morita Yousuke Michikawa Tomohiro Tamura Tetsuya Hiraishi Nobuhiro Hattori Yohei Noguchi Kazunari Nakahara Hiroki Ikeda Toshiya Ishii Chiaki Okuse Shigeru Sase Fumio Itoh Michihiro Suzuki 《International journal of molecular sciences》2016,17(9)
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully. 相似文献
57.
Tae Oike Yoshihito Sekiguchi Yuya Yoshimoto Takahiro Oike Ken Ando Wenchao Gu Yasushi Sasaki Takashi Tokino Akira Iwase Tatsuya Ohno 《International journal of molecular sciences》2022,23(1)
Radiotherapy is a definitive treatment for early-stage cervical cancer; however, a subset of this disease recurs locally, necessitating establishment of predictive biomarkers and treatment strategies. To address this issue, we performed gene panel-based sequencing of 18 stage IB cervical cancers treated with definitive radiotherapy, including two cases of local recurrence, followed by in vitro and in silico analyses. Simultaneous mutations in KRAS and SMAD4 (KRASmt/SMAD4mt) were detected only in a local recurrence case, indicating potential association of this mutation signature with radioresistance. In isogenic cell-based experiments, a combination of activating KRAS mutation and SMAD4 deficiency led to X-ray resistance, whereas either of these factors alone did not. Analysis of genomic data from 55,308 cancers showed a significant trend toward co-occurrence of mutations in KRAS and SMAD4. Gene Set Enrichment Analysis of the Cancer Cell Line Encyclopedia dataset suggested upregulation of the pathways involved in epithelial mesenchymal transition and inflammatory responses in KRASmt/SMAD4mt cancer cells. Notably, irradiation with therapeutic carbon ions led to robust killing of X-ray-resistant KRASmt/SMAD4mt cancer cells. These data indicate that the KRASmt/SMAD4mt signature is a potential predictor of radioresistance, and that carbon ion radiotherapy is a potential option to treat early-stage cervical cancers with the KRASmt/SMAD4mt signature. 相似文献
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Hitoshi Suto Yasuo Hattori Hiromaru Hirakuchi Naoto Kihara Yasumasa Nakashiki 《Structure and Infrastructure Engineering》2017,13(10):1359-1371
Steel corrosion under atmospheric conditions is a critical issue in the maintenance of structures such as electric transmission towers and bridges during their long-term operation, which are generally located at many places over a wide area. Since a major factor causing corrosion is airborne salt particles coming from the sea, wide-area distributions of the long-term cumulative amount of sea salt deposited on surfaces are needed. Moreover, since the amount of airborne sea salt varies locally with the topography, it is also important to consider the effects of topography. In this paper, a method combining a computational fluid dynamics model and a statistical procedure is proposed to efficiently estimate wide-area distributions of the cumulative amount of airborne sea salt by considering the local topography. The predicted amount of airborne sea salt decreases with increasing distance from the coast and varies with the topography and the offshore wind. A comparison between predicted and observed amounts revealed that: (1) this method appropriately estimates topographical effects on sea-salt transport and enables the estimation of deposited sea salt on structure surfaces, and (2) consideration of the trapping efficiency of sea-salt particles on structure surfaces improves the prediction accuracy. 相似文献
60.
Shinya Kato Yasuyoshi Kurokawa Shinsuke Miyajima Yuya Watanabe Akira Yamada Yoshimi Ohta Yusuke Niwa Masaki Hirota 《Nanoscale research letters》2013,8(1):361
To achieve a high-efficiency silicon nanowire (SiNW) solar cell, surface passivation technique is very important because a SiNW array has a large surface area. We successfully prepared by atomic layer deposition (ALD) high-quality aluminum oxide (Al2O3) film for passivation on the whole surface of the SiNW arrays. The minority carrier lifetime of the Al2O3-depositedSiNW arrays with bulk silicon substrate was improved to 27 μs at the optimum annealing condition. To remove the effect of bulk silicon, the effective diffusion length of minority carriers in the SiNW array was estimated by simple equations and a device simulator. As a result, it was revealed that the effective diffusion length in the SiNW arrays increased from 3.25 to 13.5 μm by depositing Al2O3 and post-annealing at 400°C. This improvement of the diffusion length is very important for application to solar cells, and Al2O3 deposited by ALD is a promising passivation material for a structure with high aspect ratio such as SiNW arrays. 相似文献