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31.
Deng Zhang Shingo Mabu Kotaro Hirasawa 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(5):474-482
Recently, pulse coupled neural network (PCNN) attracts much attention in image denoising as a nonlinear filtering technique. The PCNN‐based anisotropic diffusion (PCNN‐AD) method has been proposed previously for flicker noise reduction and its effectiveness has been demonstrated. Using the visual characteristics of PCNN, PCNN‐AD has also solved the problem of AD that AD is not able to suppress the isolate noise. However, there are still two drawbacks in PCNN‐AD, that is, time consuming and PCNN parameters' estimation. In order to improve the efficiency and the denoising performance of PCNN‐AD, a PCNN‐based method with an adaptive Pareto genetic algorithm (GA‐PCNN) has been proposed to restrain from additive white Gaussian noise (AWGN) in this paper. GA‐PCNN firstly integrates the PCNN and AD as a parallel system, then, optimizes the parameters of a simplified PCNN by the adaptive Pareto GA. Experimental results indicate that GA‐PCNN has better performances than the previous denoising techniques, i.e. median filter, Wiener filter, AD filter, and PCNN‐AD. The effectiveness of GA‐PCNN on AWGN reduction and edge preservation are shown finally. The results will also contribute to denoising in CMOS image sensors in the future. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
32.
1100 kV气体绝缘双断口断路器的开发与产品化 总被引:1,自引:0,他引:1
开发了一种用于气体绝缘组合电器(GIS)的1100kV50kASF6气体双断口断路器(GCB)。研究了这种断路器的各种特性,并成功完成了在绝缘、开断和机械性能等方面的型式试验。实现了GCB的小型化和轻量化。这种新开发的GCB已应用在中国特高压交流示范工程的GIS中,并已于2009年年初投入使用。 相似文献
33.
Biosynthesis of Trehangelin in Polymorphospora rubra K07–0510: Identification of Metabolic Pathway to Angelyl‐CoA 下载免费PDF全文
Dr. Yuki Inahashi Taro Shiraishi Dr. Kaia Palm Prof. Dr. Yoko Takahashi Prof. Dr. Satoshi Ōmura Prof. Dr. Tomohisa Kuzuyama Dr. Takuji Nakashima 《Chembiochem : a European journal of chemical biology》2016,17(15):1442-1447
Trehangelins are trehalose angelates discovered from endophytic actinomycete Polymorphospora rubra K07‐0510. We identified the trehangelin biosynthetic gene cluster, including genes that encode a glycoside hydrolase‐like protein (thgC), α‐amylase (thgD), 3‐ketoacyl‐ACP synthase III (thgI), 3‐ketoacyl‐ACP reductase (thgK), enoyl‐CoA hydratase (thgH) and acyl transferase (thgJ). Heterologous expression of thgH, thgI, thgJ and thgK confirmed the importance of these genes in the biosynthesis of trehangelin A. Enzymatic activity studies showed that ThgI catalyses the condensation of acetyl‐CoA and methylmalonyl‐CoA to 2‐methylacetoacetyl‐CoA (MAA‐CoA), ThgK catalyses NADPH‐dependent reduction of MAA‐CoA to 3‐hydroxy‐2‐methylbutyryl‐CoA (HMB‐CoA) and ThgH catalyses the dehydration of HMB‐CoA to angelyl‐CoA (AN‐CoA). This is the first report on the elucidation of the enzymatic formation of AN‐CoA. 相似文献
34.
Zhi Ning Chen Hirasawa K. Kwok-Wa Leung Kwai-Man Luk 《Vehicular Technology, IEEE Transactions on》1999,48(4):1029-1032
A new antenna combining the use of a ring dielectric resonator (DR) and an inverted F antenna (IFA) is proposed and investigated experimentally. In this application, the DR not only fills the role of a dielectric coating, but also serves the function of a radiator. The measurements of input impedance, return loss, and radiation pattern for both the IFA with the DR (IFA-DR) and the wire IFA (WIFA) are conducted at the S band. The measured data demonstrate that the IFA-DR operates in multiple resonance modes unlike a WIFA. Compared with the WIFA, the one proposed here incorporating a ring DR and an IFA is more attractive in having a smaller size and a larger impedance bandwidth 相似文献
35.
Cooking up an interactive olfactory game display. 总被引:2,自引:0,他引:2
Takamichi Nakamoto Shigeki Otaguro Masashi Kinoshita Masahiko Nagahama Keita Ohinishi Taro Ishida 《Computer Graphics and Applications, IEEE》2008,28(1):75-78
It's long been possible to give users outside an actual environment that environment's visual and auditory information and thus contribute to establishing presence. However, we've yet to establish much presence when users require olfactory information - such as in environments focused on foods, flowers, perfumes, or, in some cases, more offensive smells. Recently, several VR researchers have become interested in olfaction and olfactory displays that present smells in virtual environments (VEs). In this article, we describe our interactive olfactory display. One of our development goals is to confirm the assumption that users' interactions with the system increases presence. Thus, we used our interactive olfactory display to develop a cooking game in collaboration with electronic engineers and artists. 相似文献
36.
According to Hebb's cell assembly theory, the brain has the capability of function localization. On the other hand, it is suggested that in the brain there are three different learning paradigms: supervised, unsupervised, and reinforcement learning, which are related deeply to the three parts of brain: cerebellum, cerebral cortex, and basal ganglia, respectively. Inspired by the above knowledge of the brain in this paper we present a brainlike learning system consisting of three parts: supervised learning (SL) part, unsupervised learning (UL) part, and reinforcement learning (RL) part. The SL part is a main part learning input–output mapping; the UL part is a competitive network dividing input space into subspaces and realizes the capability of function localization by controlling firing strength of neurons in the SL part based on input patterns; the RL part is a reinforcement learning scheme, which optimizes system performance by adjusting the parameters in the UL part. Numerical simulations have been carried out and the simulation results confirm the effectiveness of the proposed brainlike learning system. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(1): 32–39, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20600 相似文献
37.
H Kataoka A Tsuda Y Tsuda A Baba H Yoshida R Hirasawa Y Tobimatsu M Nishiguchi M Semma Y Ito 《Canadian Metallurgical Quarterly》1997,20(6):714-716
We found that an antigen-specific anaphylaxis was induced by antigen challenge to the abdominal wall, ear auricle, or subcutaneous tissue in mice sensitized 9 days previously with antigen and adjuvant. The anaphylactic reaction was detected by vascular permeability at the injected site 7 minutes after challenge, which was the best time for estimation. A novel method (AW method) for induction and detection of the anaphylactic reaction in mice was established using the abdominal wall as the challenge site. This method could detect the anaphylactic response in mice 1 to 3 weeks after sensitization. The increase in vascular permeability was completely inhibited by administration of diphenhydramine. 相似文献
38.
39.
The physiological effects of hydroxypropyl‐distarch phosphate (HDP) were examined in rats. Male rats were fed a fiber‐free purified diet containing gelatinized potato starch (PS, 50 g/kg diet) that was not modified chemically or gelatinized, chemically modified potato starch (CMS, 50 g/kg diet) for 21 d. PS was used as the control. Six kinds of gelatinized HDP from potato with 2 different degrees of hydroxypropylation and 3 different degrees of cross‐linking were used as CMS. The wet weight and moisture of the fecal output of the rats fed highly hydroxypropylated HDP was 70% and 30% greater, respectively, than that in the control rats. The weights of the cecal wall and content of the rats fed highly hydroxypropylated HDP were 15% and 30% higher, respectively, than those of the control rats. The apparent absorption of Mg was 15% higher in the rats fed highly hydroxypropylated HDP than in the control rats. On the other hand, the apparent absorptions of Ca, Zn, and Fe were not affected by the diet. Cross‐linking did not influence the above‐mentioned physiological effects of HDP. Fecal excretion of bile acids and the plasma cholesterol concentration were not affected by the diet. These results show that the physiological effects of HDP depend on the hydroxypropylation but not the cross‐linking. 相似文献
40.
Sugimoto K Nomura K Nishimura T Kiso T Sugimoto K Kuriki T 《Journal of Bioscience and Bioengineering》2005,99(3):272-276
Alpha-arbutin is a tyrosinase inhibitor. We synthesized alpha-arbutin-alpha-glycosides by the transglycosylation reaction of cyclomaltodextrin glucanotransferase from Bacillus macerans using alpha-arbutin and starch as acceptor and donor molecules, respectively. We isolated and characterized two major products from the reaction mixture. The structural analyses using 13C- and 1H-NMR spectroscopy proved that they were 4-hydroxyphenyl alpha-maltoside (alpha-Ab-alpha-G1) and 4-hydroxyphenyl alpha-maltotrioside (alpha-Ab-alpha-G2). Both alpha-Ab-alpha-G1 and alpha-Ab-alpha-G2 exhibited competitive-type inhibition on human tyrosinase as alpha-arbutin does. Their K(i) values were calculated to be 0.6 mM and 2.8 mM, respectively, which is slightly and significantly higher than that of alpha-arbutin (0.2 mM). 相似文献