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71.
72.
Hiroo Konishi Suresh C. Verma Shigeyuki Sugimoto Shigeaki Ogawa 《IEEJ Transactions on Electrical and Electronic Engineering》2006,1(3):306-313
An application of the chain link converter (CLC) system, which consists of multiple single‐phase voltage source converters (VSCs) connected in parallel or series, is studied as interconnection systems. In a CLC‐high voltage direct current transmission (HVDC) system, single‐phase converters must be connected in series on the DC side to make the DC voltage high, and the DC voltage of each converter must be controlled to the same value to get an appropriate capacity. This paper describes a DC voltage balancing control (DVBC) method between series converters. Simulations and simulator tests in steady states and in transient states were carried out to confirm behaviors of the CLC‐HVDC system. Those results confirmed the viability of CLC applications to interconnection systems. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
73.
Tomoyuki Kanehira Akiko Takahashi Jun Imai Shigeyuki Funabiki 《Electrical Engineering in Japan》2015,193(4):49-57
Renewable forms of energy such as solar energy have attracted attention as alternative sources of fossil fuel. The output power of photovoltaic generation systems changes steeply. Changes in output power have an effect on the electric power quality of the power system. For that reason, a system which can smooth fluctuations of output power is required. In this paper, the moving average, modified moving average, single exponential smoothing, and double exponential smoothing methods are applied to electric power smoothing control schemes for distributed generation systems with photovoltaic generation. The reduction rate of power fluctuations and the maximum stored energy of electric double layer capacitors are adopted as system evaluation measures. To confirm the effectiveness of the power smoothing control methods, a distributed generation power system with photovoltaic generation systems is simulated with the power electronics circuit simulation software PSIM. The methods are then compared by evaluating the reduction in the capacity of electric double layer capacitors without loss in the power smoothing effect. 相似文献
74.
Thioether Macrocyclic Peptides Selected against TET1 Compact Catalytic Domain Inhibit TET1 Catalytic Activity 下载免费PDF全文
75.
Different network structures of vulcanized polyisoprene rubbers were studied by in-situ ESR and synchrotron X-ray during deformation to analyze the rupture, orientation, and strain-induced crystallization of polymer chains and network points. Rupture of network points occur, depending on network structure, and create an un-reversible change in vulcanized rubber. The flexibility of network points affects the possibility of rupture, polymer orientation and strain-induced crystallization. Peroxide vulcanized network is rigid and un-rupturable. Poly-sulfide rich vulcanized network is more flexible and less rupturable than mono-sulfide rich vulcanized network. Chain flexibility and rupturability of network points affect the strain-induced crystallization and stress-strain relation. 相似文献
76.
Shigeyuki Imura Toshihisa Watabe Kazunori Miyakawa Kei Hagiwara Hiroshi Ohtake Misao Kubota 《Journal of Materials Science: Materials in Electronics》2017,28(10):7064-7069
In this study, the surface enhancement of thin-film crystalline selenium (c-Se) is successfully demonstrated through grain refinement using chlorine (Cl) doping. We fabricated c-Se films via doping with various halogens, such as Cl, bromine (Br), and iodine (I). In particular, for Cl, we prepared c-Se films with different doping concentrations of 0, 50, and 500 ppm on glass substrates to investigate the details of concentration effects on surface enhancement. The long helical chains of Se atoms that comprise a large molecule in hexagonal Se, which is the most stable form of Se, are terminated via halogen doping into Se, leading to a marked reduction in the size of polycrystalline grains. In addition, the grain size of c-Se sharply decreases as the Cl doping concentration is increased. The mean surface roughness of a 500-ppm-Cl-doped c-Se film measured via atomic force microscopy decreased to approximately one-fourth that of the equivalent undoped c-Se film. This is a promising technology that could bring great benefits to c-Se-based imaging devices. 相似文献
77.
The effective usage of power facilities can be realized by leveling the fluctuating active power and compensating the reactive power. A fuzzy control strategy of superconducting magnetic energy storage (SMES) has been proposed for this purpose. The control results depend on the values of the scaling factors in fuzzy reasoning. Therefore, to obtain better control results, the scaling factor should be successively adjusted according to the load power fluctuations. In this paper, a control strategy based on autotuning of scaling factors and a fuzzy singleton reasoning method using backpropagation in a neural network is proposed for leveling load fluctuations. The prediction and revision of the teaching signal in terms of the energy of the SMES is proposed. The learning rate and the revision of the teaching signal are discussed. Better leveling of load power fluctuation is shown to be achievable by using fuzzy logic and neural networks. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(2): 72–81, 1997 相似文献
78.
79.
Hayama Y Fukuda Y Kawai S Hashimoto W Murata K 《Journal of Bioscience and Bioengineering》2002,94(2):166-171
In the presence of polyethylene glycol (PEG), budding cells of Saccharomyces cerevisiae in the early log phase were transformed by exogenous plasmid DNA without additional specific chemical or physical treatments. This capacity of the yeast cells to become competent was strictly dependent on the growth phase, being induced in the early log phase, becoming maximum between the early and mid log phases and then disappearing rapidly in the mid log phase. The transformation was most efficient at pH 6 and the frequency increased with increasing DNA and cell concentrations. PEGs with average molecular sizes between 1000 and 3500 showed almost the same effects and were used most efficiently at 35%. The transformation frequency of S. cerevisiae was markedly enhanced when the oxidized form of glutathione (GSSG), but not the reduced form, was included in the mixture comprising early log phase cells, plasmid DNA, and PEG, and the transformation system with GSSG could be used as a convenient transformation method for the yeast S. cerevisiae. 相似文献
80.
Qisheng Zhang Takeshi Komino Shuping Huang Shigeyuki Matsunami Kenichi Goushi Chihaya Adachi 《Advanced functional materials》2012,22(11):2327-2336
The temperature dependence of luminescence from [Cu(dnbp)(DPEPhos)]BF4 (dnbp = 2,9‐di‐n‐butylphenanthroline, DPEPhos = bis[2‐(diphenylphosphino)phenyl]ether) in a poly(methyl methacrylate) (PMMA) film indicates the presence of long‐life green emission arising from two thermally equilibrated charge transfer (CT) excited states and one non‐equilibrated triplet ligand center (3LC) excited state. At room temperature, the lower triplet CT state is found to be the predominantly populated excited state, and the zero‐zero energy of this state is found to be 2.72 eV from the onset of its emission at 80 K. The tunable emission maximum of [Cu(dnbp)(DPEPhos)]BF4 in various hosts with different triplet energies is explained in terms of the multiple triplet energy levels of this complex in amorphous films. Using the high triplet energy charge transport material as a host and an exciton‐blocking layer (EBL), a [Cu(dnbp)(DPEPhos)]BF4 based organic light‐emitting diode (OLED) achieves a high external quantum efficiency (EQE) of 15.0%, which is comparable to values for similar devices based on Ir(ppy)3 and FIrpic. The photoluminescence (PL) and electroluminescence (EL) performance of green emissive [Cu(μI)dppb]2 (dppb = 1,2‐bis[diphenylphosphino]benzene) in organic semiconductor films confirmed its 3CT state with a zero‐zero energy of 2.76 eV as the predominant population excited state. 相似文献