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2.
Present-day power systems operate with high reliability, and it is rare that a blackout will extend over an entire system swiftly and securely. This paper considers automatic power supply to loads after a complete blackout of a system. First, taking into account characteristics of generators, loads, and initial power sources, a method is proposed of allocating several generators to each load in parallel to the system and supplying power to the load sequentially. Second, to remove the imbalance between supply and demand of power, a method is proposed of adjusting the amount of supply and generation according to a present imbalance and the sum of past ones. Third, to automatically issue orders for start-up, parallel, follow-up, stand-by, and stoppage of generators, several rules for each power station are set and an expert system is made based on them. Finally, the expert system is applied to a model power system, and it is verified that it can restore loads without any trouble for a complete blackout which occur at any time of a day and in any restoration pattern. 相似文献
3.
Naoto Suzuki 《Electrical Engineering in Japan》2010,171(2):23-30
In Kyushu Electric Power's 6.6‐kV distribution system, after a single‐phase ground fault occurred in the circuit of a distribution line, we experienced a phenomenon in which the analogue ground directional relays of the other circuits linked to the same bank were simultaneously tripped. In this paper, focus is placed on the mechanism and possibility of simultaneous tripping of ground directional relays. This mechanism was examined in an experiment carried out using an analogue simulator. The results of the test revealed that such simultaneous tripping was attributable to the neutral instability phenomenon of grounding potential transformers installed in an isolated neutral system. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(2): 23–30, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20919 相似文献
4.
Kenji Kinashi Hironori ShinkaiWataru Sakai Naoto Tsutsumi 《Organic Electronics》2013,14(11):2987-2993
Photorefractive (PR) performances of methyl-substituted poly(triarylamine) (PTAA)-based PR device were demonstrated using chemically modified electrodes (CMEs) of self-assembled monolayer (SAM) coated indium-tin-oxide (ITO) electrodes. The SAM-ITO electrodes successfully suppressed dark current which blocks the formation of space-charge field and also causes the dielectric breakdown. The PR device consisted of composite of PTAA, 4-azacycloheptylbenzylidenemalononitrile (7-DCST), N-ethylcarbazole (ECz), and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) sandwiched between the SAM-ITO electrodes. The PR devices showed the PR performances: optical gain Γ, refractive index Δn, diffraction efficiency η, response time τ, sensitivity S, phase shift Φ, trap-limited field Eq, number density of traps NT, and space-charge field ESC. The remarkable response time of 11.3 ms was achieved at the low electric field of 20 V μm−1, which was comparable to the response time of high-definition television (HDTV) quality of 16 ms. Our approach will widen the usage of higher mobility materials to photorefractive field and give us more favorable materials to achieve the best performance of photorefractivity in the future. 相似文献
5.
Hiroyuki Koide Satoshi Hirano Takafumi Ide Kazuhiro Saito Hikaru Suzuki Go Yasuno Yoshitaka Hamashima Sei Yonezawa Naoto Oku Tomohiro Asai 《Advanced functional materials》2021,31(3):2005641
Protein affinity reagents (e.g., antibodies) are often used for basic research, diagnostics, separations, and disease therapy. Although a lot of “synthetic” protein affinity reagents have been developed as a cost-effective alternative to antibodies, their low biocompatibility is a considerable problem for clinical application. Lipid nanoparticles (LNP) represent a highly biocompatible drug delivery agent. However, little has been reported that LNP itself works as a protein affinity reagent in living animals. Here, LNP is engineered for binding to and neutralizing a target toxic peptide in living animals by multifunctionalization with amino acid derivatives. Multifunctionalized LNP (MF-LNP) is prepared using amino acid derivative-conjugated lipids. Optimized MF-LNP exhibits nanomolar affinity to the target toxic peptide and inhibits toxic peptide-dependent hemolysis and cytotoxicity. In addition, MF-LNP captures and neutralizes the toxic peptide after intravenous injection in the bloodstream; in addition, MF-LNP does not release the toxic peptide in the accumulated organ. These results reveal the potential of using LNP as a highly biocompatible protein affinity reagent such as an antidote. 相似文献
6.
We discuss optimum inspection policies by introducing the inspection density. We derive the optimum inspection policy by using this inspection density. The models discussed are: 1) the basic model, 2) the basic model with checking time, and 3) the basic model with imperfect inspection. For each model, we obtain the approximate optimum inspection policy minimizing the total s-expected cost by applying the calculus of variations. 相似文献
7.
Shuyan Gao Naoto Koshizaki Hideo Tokuhisa Emiko Koyama Takeshi Sasaki Jae‐Kwan Kim Joonghyun Ryu Deok‐Soo Kim Yoshiki Shimizu 《Advanced functional materials》2010,20(1):78-86
Colloidal Au‐amplified surface plasmon resonance (SPR), like traditional SPR, is typically used to detect binding events on a thin noble metal film. The two major concerns in developing colloidal Au‐amplified SPR lie in 1) the instability, manifested as a change in morphology following immersion in organic solvents and aqueous solutions, and 2) the uncontrollable interparticle distance, determining probe spacing and inducing steric hindrance between neighboring probe molecules. This may introduce uncertainties into such detecting techniques, degrade the sensitivity, and become the barricade hampering colloidal Au‐based transducers from applications in sensing. In this paper, colloidal Au‐amplified SPR transducers are produced by using ultrathin Au/Al2O3 nanocomposite films via a radio frequency magnetron co‐sputtering method. Deposited Au/Al2O3 nanocomposite films exhibit superior stability, and average interparticle distances between Au nanoparticles with similar average sizes can be tuned by changing surface coverage. These characteristics are ascribed to the spacer function and rim confinement of dielectric Al2O3 and highlight their advantages for application in optimal nanoparticle‐amplified SPR, especially when the probe size is smaller than the target molecule size. This importance is demonstrated here for the binding of protein (streptavidin) targets to the probe (biotin) surface. In this case, the dielectric matrix Al2O3 is a main contributor, behaving as a spacer, tuning the concentration of Au nanoparticles, and manipulating the average interparticle distance, and thus guaranteeing an appropriate number of biotin molecules and expected near‐field coupling to obtain optimal sensing performance. 相似文献
8.
This paper considers the optimal spare ordering policies for a cold standby redundant system with two dissimilar units. Especially, the planned maintenance schedule with salvage cost is discussed. The failure time distributions for respective units are assumed to be arbitrary. By applying the expected cost per unit time in the steady-state and the stationary availability as criteria of optimality, the optimal ordering policy minimizing or maximizing each criterion is obtained under some economical and/or physical assumptions. Finally, numerical examples are presented, and the effect of the failure time distributions for the optimal ordering policy is examined in detail. 相似文献
9.
Benzobisthiazole as Weak Donor for Improved Photovoltaic Performance: Microwave Conductivity Technique Assisted Molecular Engineering 下载免费PDF全文
Masashi Tsuji Akinori Saeki Yoshiko Koizumi Naoto Matsuyama Chakkooth Vijayakumar Shu Seki 《Advanced functional materials》2014,24(1):28-36
New donor–acceptor‐type copolymers comprised of benzobisthiazole (BBTz) as a weak donor rather than acceptor are proposed. This approach can simultaneously lead to deepening the HOMO and LUMO of the polymers with moderate energy offset against fullerene derivatives in bulk heterojunction organic photovoltaics. As a proof‐of‐concept, BBTz‐based random copolymers conjugated with typical electron acceptors: thienopyrroledione (TPD) and benzothiadiazole (BT) based on density functional theory calculations are synthesized. Laser‐flash and Xe‐flash time‐resolved microwave conductivity (TRMC) evaluations of polymer:[6,6]‐phenyl C61 butyric acid methyl ester (PCBM) blends are conducted to screen the feasibility of the copolymers, leading to optimization of processing conditions for photovoltaic device application. According to the TMRC results, alternating BBTz‐BT copolymers are designed, exhibiting extended photoabsorption up to ca. 750 nm, deep HOMO (–5.5 to –5.7 eV), good miscibility with PCBM, and inherent crystalline nature. Moreover, the maximized PCE of 3.8%, the top‐class among BBTz‐based polymers reported so far, is realized in an inverted cell using TiOx and MoOx as the buffer layers. This study opens up opportunities to create low‐bandgap polymers with deep HOMO, and shows how the device‐less TRMC evaluation is of help for decision‐making on judicious molecular design. 相似文献
10.
Naoto Kimbara Akio Nishijima Toshio Sato Yuji Yoshimura Hiromichi Shimada Nobuyuki Matsubayashi Akinori Yukimura 《Catalysis Letters》1990,6(3-6):409-415
TiN supported molybdenum sulfide catalysts showed much higher activity for cleavage of C-C bonds than oxide supported molybdenum sulfide catalysts, indicating the possibility of a new generation of supports for hydroprocessing catalysts. 相似文献