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81.
We have developed a new method that can measure movement of overhead power lines in the wind. This method uses images from an ITV camera system. The sway of the power line is videotaped and analyzed. Its measured frequency response to wind is compared to a theoretical model. It is found that the new method yields results that are in good agreement with those obtained from the theoretical model for frequency response less than 0.5 Hz. With the result of frequency response, we can calculate the sway mode of the power line in the wind. Our method also offers displacement of the sway of the cable. We compared our method to the laser measurement, and found a difference of about 10 cm at 255 m from the camera. © 2001 Scripta Technica, Electr Eng Jpn, 137(4): 18–24, 2001 相似文献
82.
Bacterial phosphate metabolism and its application to phosphorus recovery and industrial bioprocesses 总被引:1,自引:0,他引:1
Ryuichi Hirota Akio Kuroda Junichi Kato Hisao Ohtake 《Journal of Bioscience and Bioengineering》2010,109(5):423-432
Enhanced biological phosphorus removal (EBPR) has become a well-established process and is currently applied in many full-scale wastewater treatment processes. Phosphorus recovered from EBPR waste sludge can be used as a raw material for the fertilizer industry, if a sound recycling strategy is developed and applied. In this review, we summarize our current knowledge on phosphate metabolism in bacteria, focusing on molecular mechanisms of bacterial polyphosphate (polyP) accumulation. A simple method for releasing polyP from EBPR waste sludge and recovering phosphorus in a reusable form for the fertilizer industry is presented. We also describe a recent development of bioprocesses for the expanded use of polyP in the production of value-added chemicals. 相似文献
83.
Ryuichi Hayashi Hayato Obo Nozomi Takeuchi Koichi Yasuoka 《Electrical Engineering in Japan》2015,190(3):9-16
Complete decomposition of perfluorooctanoic acid (PFOA) at a concentration of 41.4 mg/L and perfluorooctane sulfonate (PFOS) at a concentration of 60 mg/L in water was successfully completed by DC plasma within oxygen bubbles. PFOA and PFOS were decomposed completely after 3‐h operation and 8‐h operation, respectively. The decomposition efficiency was evaluated by measuring the amounts of fluorine ions that were detached from PFOA and PFOS in the solution. As indicated by the measurement of LC/MS, the main byproducts generated during the plasma treatment turned out to be perfluorocarboxylic acids. For practical application, 2‐parallel operation of DC plasma was also demonstrated as a basic technology for a large capacity reactor. The decomposition efficiency of 2‐parallel operation was at the same level as that of single operation. 相似文献
84.
Akira Yamaguchi Takamichi Watanuki Ryuichi Masutomi Hidehiko Ishimoto 《Journal of Low Temperature Physics》2005,138(1-2):307-312
No Heading The nuclear susceptibility of liquid 3He in Grafoil pre-plated by 2.5 and 3.5 layers of 4He has been studied with a cw NMR method at temperatures between 0.7 and 100 mK under various liquid pressures. The 3.5 layers of 4He pre-plating suppresses a formation of the first and second solid 3He layer, eliminating most of surface magnetization at saturated vapor pressure. However, with increasing liquid pressure, a magnetization obeying a Curie Weiss law gradually grows in the same way as in the previous experiment for pure liquid 3He. This magnetization, induced by pressurization, is attributable to the formation of solid 3He layer above the pre-plated 4He.PACS numbers: 67.80.Jd, 75.70 Cn, 67.70.+n. 相似文献
85.
86.
在电力系统中实现CO2的有效减排,是当前电力行业所面临的突出问题,而电源规划则将在其中发挥着至关重要的作用。文中分析了面向低碳目标的电源规划模式,在揭示各类低碳要素对传统电源规划模式的影响机制与作用原理的基础上,对实施低碳电源规划的关键技术进行了深入的研究;并分析了在不同的低碳要素场景下,中国电力行业实施低碳化发展的规划前景与碳排放特性,进而讨论了各类低碳要素的应用在实施CO2减排中的作用与潜力。文中的结果为中国电力行业的CO2减排工作提供了有益的参考。 相似文献
87.
Yuichi Kaji Ryuichi Nakanishi Hiroyuki Seki Tadao Kasami 《Computational Intelligence》1994,10(4):440-452
A number of grammatical formalisms have been proposed to describe the syntax of natural languages, and the universal recognition problems for some of those classes of grammars have been studied. A universal recognition problem for a class Q of grammars is the one to decide, taking a grammar G ∈ G and a string ui as an input, whether G can generate w or not. In this paper, the computational complexities of the universal recognition problems for parallel multiple context-free grammars, multiple context-free grammars, and their subclasses are discussed. 相似文献
88.
The free settling behavior of the cylindrical particles made of four kinds of materials with horizontal motion in the stagnant water observed with an aid of the image sensor anemometer in the Reynolds number ranged from about 150 to 1000 was investigated in this paper. The four kinds of materials were finished into cylindrical specimens having the diameters “d” of 1.5 to 3.0 mm and the ratios of “d” to the length of specimen “1s” of d/1s = 1/2 to 1/3.5.
From the experimental results, the settling behavior of the particles was found to be simply expressed by the equation of a simple harmonic motion. By correcting the drag coefficient of the cylindrical particles with a correction factor which is obtained from the simple harmonic motion, the relationship between the drag coefficient and Reynolds number for the cylindrical particles was found to be parallel to that for the spherical particles. 相似文献
From the experimental results, the settling behavior of the particles was found to be simply expressed by the equation of a simple harmonic motion. By correcting the drag coefficient of the cylindrical particles with a correction factor which is obtained from the simple harmonic motion, the relationship between the drag coefficient and Reynolds number for the cylindrical particles was found to be parallel to that for the spherical particles. 相似文献
89.
Dissolution properties of some fly ash fillers applying to geopolymeric materials in alkali solution
Dissolution properties of three kinds of fly ash including a Pressurized Fluidized Bed Combustion (PFBC) ash from a novel
type of fluidized bed combustion boiler have been studied by leaching in different concentrations of caustic soda solution
up to 15 N at 25 °C and 80 °C, stirring for 1 h with liquor/solid ratio = 10. Liquors sampled by a centrifugal separator were
chemically analyzed by ICP technique. A blast furnace slag was also studied for reference. Results showed that Ca2+ dissolved relatively large amount in genuine water, but no marked dissolution was detected with increasing NaOH concentrations
of the leaching solution. No enhanced dissolution of Al3+ was detected for ordinary fly ashes collected from pulverized coal combustion boilers even with increasing concentrations
of solution at 25 °C, whereas enhanced dissolution of Al3+ was observed at 80 °C, when 5 N was reached and more. On the contrary, appreciable increasing was noted on the dissolution
of Si4+ with increasing NaOH concentrations even at 25 °C for the ordinary fly ashes and the Si4+ dissolution became enhanced at 80 °C, specifically in 5 N and more. 相似文献
90.
Transformation of cellobiose to 3-ketocellobiose by the EDTA-treated Agrobacterium tumefaciens cells
Agrobacterium tumefaciens cells treated with EDTA were used as a biocatalyst for the transformation of cellobiose to 3-ketocellobiose. The effects of pH of the reaction medium and temperature on the reaction rate and the selectivity during the transformation by the cells were examined, and it was found that the optimum reaction conditions were pH 6 and 15 degrees C. The selectivity was about 0.8 under these conditions. The substrate concentration had no significant effect on the selectivity up to 300 mmol/I. 相似文献