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191.
Multimedia Tools and Applications - Computational models of saliency estimation have been studied in a wide range of research fields, including visual perception, image processing, computer vision,... 相似文献
192.
A Comparison of Electric Power Smoothing Control Methods for Distributed Generation Systems
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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
193.
Haruki Ejiri Akiko Kumada Kunihiko Hidaka Taiki Donen Kentaro Kokura 《Electrical Engineering in Japan》2019,206(1):32-41
Breakdown voltages of vacuum gaps become lower when the gaps are contaminated by metallic and ceramic microparticles. In this paper, the motion of the microparticles in the gap is simulated using Monte Carlo method in order to evaluate the effect of parameters upon motion and the removal time of the microparticles. As the parameters, we focused on the material of the microparticle, the frequency, the peak value of the applied voltage, the gap length, and the diameter of the lower and upper electrodes. It turned out that the maximum time needed to remove all microparticles could be expressed as multiple regression function. It is suggested that the reliability of the microparticle removal can be increased by spark conditioning with opening/closing operation. 相似文献
194.
Light‐Emitting Devices: Fabrication of Organic Light‐Emitting Devices Comprising Stacked Light‐Emitting Units by Solution‐Based Processes (Adv. Mater. 8/2015)
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195.
Tomohisa Nagano Nobuyoshi Seki Yoichi Tomita Tomonori Sugita Yuta Aida Munenori Itagaki Satoshi Sutoh Hiroshi Abe Akihito Tsubota Yoshio Aizawa 《International journal of molecular sciences》2015,16(9):20576-20594
Reduced low-density lipoprotein (LDL) cholesterol level is a characteristic feature of dyslipidemia in chronic hepatitis C virus (HCV) infection. However, abnormality in serum triglyceride (TG) has not been fully investigated. To clarify the impact of HCV genotype 1b (G1b) infection and advanced fibrosis on serum TG profiles, TG concentrations in lipoprotein fractions were examined in fasting sera from 185 subjects with active or cleared HCV infection by high-performance liquid chromatography. Serum lipoproteins were fractionated into four classes: chylomicron, very low-density lipoprotein (VLDL), LDL, and high-density lipoprotein (HDL). Then, the significance of HCV G1b infection on TG levels in each lipoprotein fraction was determined using multiple regression models. We found that active HCV G1b infection was positively associated with high HDL-TG levels and low VLDL-TG levels, independent of other factors included in the regression model. In VLDL sub-fractions, active HCV infection was only found to be associated with low levels of large VLDL-TG. Similarly, advanced liver fibrosis in chronic HCV G1b infection was associated with high levels of LDL-TG, HDL-TG, and small VLDL-TG, independent of other clinical factors. These findings indicate that active HCV G1b infection and advanced fibrosis are closely associated with abnormal serum TG profiles. 相似文献
196.
Miho Nakamura Masahiro Inuzuka Kazuaki Hashimoto Akiko Nagai Kimihiro Yamashita 《Journal of Materials Science》2011,46(22):7335-7343
Because of its excellent mechanical properties, yttria-stabilized zirconia is currently used as an orthopedic and dental material.
In this study, we have improved the bioactivity of yttria-stabilized zirconia by a combination of electrical polarization
and chemical treatment. The phase transformation from tetragonal to monoclinic ZrO2 after alkaline treatment was inhibited on positively charged yttria-stabilized zirconia surfaces compared with negatively
charged and conventional surfaces. During polarization, some oxide ions move from the positively charged surface to the negatively
charged surface, leading to an increase in oxygen vacancies on the positive surface and hence greater formation of Zr–OH when
this surface was exposed to alkaline solution. This then reduced the water adsorption at this surface and consequently reduced
the rate of cleavage of Zr–O–Zr bonds. The bioactivity was assessed by immersing the samples in simulated body fluid and evaluating
the growth of apatite on the surfaces. The combination of polarization and alkaline treatment increased the bioactivity in
vitro. 相似文献
197.
Yoh-Ichiro Ogita Masayuki TachiharaYotaro Aizawa Naoyuki Saito 《Thin solid films》2011,519(14):4469-4472
The passivation effects of AlOx films were investigated for p-type crystalline Si (c-Si) solar cells. The AlOx films were deposited on 10 Ωcm c-Si substrates by catalytic chemical vapor deposition (Cat-CVD) using tri-methyl aluminum (TMA) and O2 at a film temperature of 230 °C. The surface recombination velocity (S0) at the AlOx/Si interface was measured to be below 0.5 cm/s for AlOx films deposited with O2/TMA gas flow-rate ratios of 15-35. This ultra low S0 was achieved primarily by band bending due to the negative interface fixed-charge density (Nf) of an order of 1012 charges/cm2. The decrease in interface trapping density Dit in the negative fixed charge region assists in decreasing S0. 相似文献
198.
The effects of specific chemical functionalities on the neurite outgrowths of embryonic chick dorsal root ganglia (DRG) neurons and PC12h cells were investigated using a set of chemically functionalized surfaces prepared by self-assembled monolayers (SAMs) of alkanethiolates with R = NH2, COOH, and CH3 on patterned gold surfaces. The numbers of neurons with neurite outgrowths were compared in the course of a two-week cultivation period. Neurons with neurite outgrowths were observed predominantly on a patterned SAM of long-chain alkanethiolates with amino groups. After about two weeks, the neurons detached from the patterned SAM. However, the activity of beta-galactosidase immobilized via a patterned SAM did not decrease over a 13-d period, reflecting the long-term stability of the SAM. Therefore, the neurons became detached upon cell death. These results demonstrate that the patterned SAM of 11-amino-1-undecanethiolate is a scaffold suitable for making cell chips. 相似文献
199.
Kagaya N Kamiyoshi A Tagawa Y Akamatsu S Isoda K Kawase M Yagi K 《Journal of Bioscience and Bioengineering》2005,99(1):81-83
In screening for effective additives for the long-term culture of hepatocytes, the hepatoprotective effect of alpha1-acid glycoprotein (AGP) was observed. AGP prevented primary hepatocytes from undergoing cell death induced by the chemical toxin, bromobenzene. Moreover, AGP added to medium was found to maintain the number of viable hepatocytes for as long as 6 d. The hepatoprotective effect of AGP was lost by removing sialic acid groups at the N-glycan chain terminal of AGP. It is shown that the complete form of N-glycan chain is needed for the hepatoprotectivity of AGP. 相似文献
200.
Nagaosa K Kishimoto A Kizu R Nakagawa A Shiratsuchi A Nakanishi Y 《Reproduction (Cambridge, England)》2007,133(1):21-27
Natural and artificial substances present in the environment can affect our health. Testicular toxicants in particular are troublesome, because they disturb gonadal function of males. Translocation of substances into the seminiferous epithelium where sperm production proceeds is restricted due to the blood-testis barrier, but this permeability barrier temporarily disappears under physiological and sub-physiological conditions. This means that any substance could enter the seminiferous epithelium and disturb sperm production. To reduce the risk posed by such toxins, it is important to accurately determine which substances possess the toxicity. However, existing assay systems are not satisfactory in terms of both accuracy and sensitivity. Here, we report the establishment of such a system. We injected the androgen antagonists, flutamide and vinclozolin, directly into seminiferous tubules of live mice, which had been treated with busulfan for a temporal arrest of spermatogenesis, and the testes were histologically examined to see the effect of the injected materials on spermatogenesis that was in the process of recovery. The injection of either substance brought about a severe impairment of spermatogenesis at an amount over a million times smaller than that used in the previous assay systems where animals are administered with test substances outside of the testis. In contrast, these androgen antagonists at the same doses showed lesser effects when intratubularly or intraperitoneally administered into mice that had not been pretreated with busulfan. We propose that the method adopted in this study is a novel assay system to identify potential testicular toxicants. 相似文献