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31.
32.
Study on Lightning Protection Measures for Distribution Lines and Customer Equipment against Back Flow Lightning Current from Radio Communication Station
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KAZUYUKI ISHIMOTO AKIRA ASAKAWA TOMOYUKI SATO YASUHIRO MIYAMA 《Electrical Engineering in Japan》2017,200(4):30-44
Recently, with the expansion of communication network areas, the number of radio communication stations built in the neighborhood of customer houses has increased. If lightning strikes a communication radio tower, part of the lightning current flows into the distribution line and into customer houses. This may cause the failure of distribution lines or customer equipment. To protect distribution lines and customer equipment from lightning faults, it is necessary to analyze the surge phenomena in distribution lines and customer equipment and take appropriate protection measures. In this study, we examined the effect of lightning protection measures for distribution lines and customer equipment against lightning strikes to a communication tower. First, using an actual‐scale test distribution line, we measured the lightning current flowing into distribution lines and customer equipment. Second, we quantitatively examined the effect of lightning protection measures by lighting surge analysis while changing each parameter. From the experimental and analytical results, we show that the proposed protection measures can reduce the lightning current flowing into distribution lines and customer equipment. 相似文献
33.
S. FUJITA T. R. C. WELLS W. USHIO H. SATO M. M. EL‐GOMATI 《Journal of microscopy》2010,239(3):215-222
Even though the Schottky emitter is a high‐brightness source of choice for electron beam systems, its angular current intensity is substantially lower than that of thermionic cathodes, rendering the emitter impractical for applications that require high beam current. In this study, two strategies were attempted to enhance its angular intensity, and their experimental results are reported. The first scheme is to employ a higher extraction field for increasing the brightness. However, the tip shape transformation was found to induce undesirably elevated emission from the facet edges at high fields. The second scheme exploits the fact that the angular intensity is proportional to the square of the electron gun focal length [ Fujita, S. & Shimoyama, H. (2005) Theory of cathode trajectory characterization by canonical mapping transformation. J. Electron Microsc. 54 , 331–343], which can be increased by scaling‐up the emitter tip radius. A high angular current intensity (JΩ∼ 1.5 mA sr−1) was obtained from a scaled‐up emitter. Preliminary performance tests were conducted on an electron probe‐forming column by substituting the new emitter for the original tungsten filament gun. The beam current up to a few microamperes was achieved with submicron spatial resolution. 相似文献
34.
KENJI SATO CHIE TANAKA MAKOTO KOTARU HIDEKI YOSHKAWA MAKOTO KAWABATA TSUNEO KEUCHI KENTA SATO YASUSHI NAKAMURA KOZO OHTSUKI 《Journal of Food Biochemistry》2001,25(5):397-409
The objective of the present study is to compare the protein cross‐linking reaction in Alaska pollock surimi that is catalyzed by a commercially available microbial transglutaminase and by endogenous Alaska pollock transglutaminase. The endogenous transglutaminase was inhibited by EGTA and activated by CaCl2 The microbial transglutaminase was added to the salted surimi with and without EGTA and CaCl2. These surimi pastes were incubated at 25C up to 24 h followed by cooking at 90C. The resultant gels were fractionated into soluble and insoluble (aggregate) fractions by SDS‐urea extraction. Compositional analysis revealed that the aggregate consisted predominantly of cross‐linked myosin heavy chain. The distribution of ?‐(γ‐glutamyl)lysine isopeptide in the soluble and aggregate fractions andpeptide mapping analyses of the aggregate fraction demonstrate that the formation of isopeptide cross‐links in Alaska pollock surimi proteins during suwari process differs when catalyzed by the microbial transglutaminase and endogenous transglutaminase. 相似文献
35.
QINGJIE GUO TOSHIYUKI SUDA JUNI'CHI SATO GUANGXI YUE 《Chemical Engineering Communications》2013,200(10):1329-1342
Minimum fluidization velocity and agglomeration behavior were investigated at high temperature in an 80?×?30?mm two-dimensional quartz fluidized bed and in an 82?mm i.d. circular fluidized bed. Bed materials tested were two sizes of glass beads as well as three sizes of fluidized bed combustor (FBC) ash. The minimum fluidization velocity decreased with increasing bed temperature, whereas the minimum sintering fluidization velocity increased with the bed temperature. The sintering of glass beads belongs to visco plastic sintering, the first type. FBC ash agglomerate has higher amounts of SiO2, Al2O3, Na2O, K2O, and SiO2 than in the original ash, indicating that low melting eutectics were formed and that the liquid phase in a silicate system was formed. The agglomeration of FBC ash belongs to the second type, an excessive quantity of liquid being formed by melting or chemical reaction. 相似文献
36.
综合型设备系统通信网络iopeNet概要 总被引:1,自引:1,他引:0
本篇论文介绍的是,将建筑物内部中分散存在的各类机器设备所属的原有网络在上层组成一个可联动的设备系统通信网络,即iopeNet。它具有能够轻松地搭载于嵌入式设备、组成结构重量轻、能够确保设备之间进行实时通信、与Web浏览器之间具有很高的融洽性等特点。 相似文献
37.
AKIKO MATSUO KENJI SATO EUN YOUNG PARK YASUSHI NAKAMURA KOZO OHTSUKI 《Journal of Food Biochemistry》2010,34(1):195-205
Brown rice-added breads were prepared with and without crude and purified Aspergillus niger phytase preparations. By adding 30% (w/w) brown rice flour and no phytase preparation, the phytate (myo-inositol hexaphosphate; IP6 ) content of the bread was increased and the loaf volume was reduced. The direct addition of a food-additive grade phytase preparation (3,000 U) resulted in a significant decrease in the IP6 content. However, it collapsed the bread crust. The crude phytase preparation had significant protease and amylase activities. A simple chromatographic method for the separation of phytase activity from the protease and amylase activities was developed. By using purified phytase, the IP6 content was reduced without any adverse effects on the rising of the bread, which indicates that protease and amylase may be responsible for the collapse of the crust by the commercial phytase preparation.
Phytate in unrefined cereals and beans lowers bioavailability of minerals. On the other hand, these materials are rich in health-promoting components. To reduce the phytate in them during processing, some commercially available phytase preparations are now used. However, we found that such preparation contains significant amylase and protease activities, which may cause adverse effect on the appearance and textural properties of final products. To solve these problems, a simple and inexpensive procedure for separation of phyatase from amylase and protease was developed in the present study. The purified phytase can reduce phytate in brown rice-added bread without adverse effect on rising of bread. These results would encourage prepare the phytase preparation in high purity in an industrial scale to improve nutritional value of unrefined cereal- and bean-based functional foods. 相似文献
PRACTICAL APPLICATIONS
Phytate in unrefined cereals and beans lowers bioavailability of minerals. On the other hand, these materials are rich in health-promoting components. To reduce the phytate in them during processing, some commercially available phytase preparations are now used. However, we found that such preparation contains significant amylase and protease activities, which may cause adverse effect on the appearance and textural properties of final products. To solve these problems, a simple and inexpensive procedure for separation of phyatase from amylase and protease was developed in the present study. The purified phytase can reduce phytate in brown rice-added bread without adverse effect on rising of bread. These results would encourage prepare the phytase preparation in high purity in an industrial scale to improve nutritional value of unrefined cereal- and bean-based functional foods. 相似文献
38.
Hydrated alkaline earth cyclo-octaphosphates were made by adding an aqueous solution of alkaline earth chlorides into an aqueous solution of sodium cyclo-octaphosphate. Thermal properties of the compounds were studied by TG-DTA analysis. The water of crystallization was removed below 200°C. The cyclo-octaphosphates decomposed to produce many phosphate species up to about 500°C, and they finally reorganized to metaphosphates. The overall thermal reaction of alkaline earth cyclo-octaphosphates can be written by the equation. M4(PO3)8 · nH2O 4M(PO3)2 + nH2O 相似文献
39.
Masahiko SATO Takafumi SAKURAI Yukiyoshi KAMEYAMA Atsushi IGARASH 《Frontiers of Computer Science in China》2008,2(1):12-21
The notion of meta-variable plays a fundamental role when we define formal systems such as logical and computational calculi.
Yet it has been usually understood only informally as is seen in most textbooks of logic. Based on our observations of the
usages of metavariables in textbooks, we propose two formal systems that have the notion of meta-variable.
In both calculi, each variable is given a level (non-negative integer), which classifies variables into object variables (level
0), meta-variables (level 1), metameta-variables (level 2) and so on. Then, simple arity systems are used to exclude meaningless
terms like a meta-level function operating on the metameta-level. A main difference of the two calculi lies in the definitions
of substitution. The first calculus uses textual substitution, which can often be found in definitions of quantified formulae: when a term is substituted for a meta-variable,
free object-level variables in the term may be captured. The second calculus is based on the observation that predicates can
be regarded as meta-level functions on object-level terms, hence uses capture-avoiding substitution.
We show that both calculi enjoy a number of properties including Church-Rosser and Strong Normalization, which are indispensable
when we use them as frameworks to define logical systems. 相似文献
40.
Tadatake SATO Kenichi TASHIRO Yoshizo KAWAGUCHI Hideki OHMURA Haruhisa AKIYAMA 《等离子体科学和技术》2019,21(3):34021-181
Laser-induced breakdown spectroscopy(LIBS) was examined to detect a trace substance adhered onto Al alloys for the surface inspection of materials to be adhesively bonded. As an example of Si contamination, silicone oil was employed and sprayed onto substrates with a controlled surface concentration. LIBS measurements employing nanosecond UV pulses(λ?=?266 nm) and an off-axis emission collection system with different detecting heights were performed. Because surface contaminants are involved in the plasma formed by laser ablation of the substrates, the relative contribution of the surface contaminants and the substrates to the plasma emission could be changed depending on the conditions for plasma formation. The limit of detection(LOD) was evaluated under several detecting conditions for investigating the factors that affected the LOD. A significant factor was the standard deviation values of signal intensities obtained for the clean substrates. This value varied depending on the measurement conditions.For the Al alloy(A6061), the smallest LOD obtained was 0.529 μg?·?cm~(-2). Furthermore, an improved LOD(0.299 μg?·?cm~(-2)) was obtained for the Al alloy with a lower Si content. 相似文献