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81.
Noboru Kikuchi 《Computer Methods in Applied Mechanics and Engineering》1983,37(1):109-123
Three-node triangular elements obtained from the intersecting diagonals of quadrilaterals are thoroughly investigated for the penalty method formulation of incompressible problems such as Stokes flow, Navier-Stokes flow, and small-deformation rubber elasticity. Equivalence of the present formulation to the one using 4-node quadrilateral isoparametric elements with selective reduced integration, is presented. Convergence, instability phenomenon, smoothing of the pressure distribution are studied together with decompositions into triangular elements. 相似文献
82.
83.
Suzuki Y. Shimada M. Mineno H. Shinozuka T. Kuroiwa H. Inomata H. 《Selected Areas in Communications, IEEE Journal on》1983,1(4):674-680
A site diversity switching experiment system for satellite earth links adopting PCM/PSK/TDMA is introduced. Results of downlink switching experiments using CS (30/20 GHz) are presented. Investigations of measuring time of signal quality for minimizing the diversity. switching error are made in point of Allan variance of bit error rate (BER) and of the defined switching error rate. 相似文献
84.
Noboru Yamazaki Seiichi Nakahama Akira Hirao Juheiji Kawabata Hiromichi Noguchi Yasuzo Uchida 《Polymer Bulletin》1980,2(4):269-274
Summary Catalysis of cationic polyelectrolytes for the decarboxylation of 6-nitrobenzisoxazole-3-carboxylate anion was studied in a buffer solution (pH=9.0). Cross-linked poly (4-vinylpyridinium) salts prepared from 4-vinylpyridine and , -dibromides were used as cationic catalysts. The cross-linked catalysts were found to accelerate markedly the decarboxylation in comparison with the linear water-soluble analogues. Effect of the polymer structure such as the length of (CH2)x linkages between positive charges on the catalytic activity was examined. It was suggested that the acceleration by the cross-linked polymer catalysts would be due to the hydrophobic microenvironment around the catalytic sites. 相似文献
85.
T Hidaka K Aisaka N Inomata M Furuya T Inoue M Omata M Yoshida T Miyazaki T Ohno T Ishihara 《Canadian Metallurgical Quarterly》1993,101(5):309-325
The cardiovascular and diuretic actions of carperitide were studied in experimental animals. Carperitide relaxed various canine arteries and veins that were contracted by high K+ or norepinephrine. Carperitide stimulated particulate guanylate cyclase from rat thoracic aortas. Carperitide had almost no effect on coronary perfusion pressure or heart rate, but caused a slight decrease in contractile force in isolated guinea pig hearts. Carperitide tended to decrease isoproterenol-induced renin release from isolated rat kidney slices and elicited decreases in angiotensin II-induced aldosterone release from bovine zona glomerulosa cells. Intravenous injection of carperitide elicited decreases in arterial blood pressure and total peripheral resistance in the anesthetized and conscious dogs. Carperitide also elicited transient increases in cardiac output and coronary blood flow followed by slight decreases in them. Intravenous infusion of carperitide elicited decreases in pulmonary capillary wedge pressure, pulmonary pressure and right atrial pressure in association with elevating plasma carperitide (ANP like immuno-reactivity) level in dogs with heart failure induced by coronary artery occlusion and saline loading. These results suggest that carperitide decreases both preload and afterload and can improve the untoward hemodynamic alterations in animals with acute experimental heart failure. 相似文献
86.
87.
The thickness of the glass substrate used in liquid crystal displays continues to be decreased from its original thickness of 1.1 mm for the purpose reducing size and weight. The aim of this study was to clarify the influence of the glass substrate thickness during laser scribing with crack propagation caused by laser heating followed by quick quenching. The laser scribe conditions for soda-lime glass substrates with thickness equal to or less than 1.1 mm were obtained in laser irradiation experiments. Two-dimensional thermal elasticity analysis was conducted with a finite element method based on the scribable conditions obtained in the experiment. The laser scribable conditions can then be estimated by the upper limit of the maximum surface temperature, Tmax, and the lower limit of the maximum tensile stress, σtmax, in the cooling area, regardless of the glass substrate thickness. There is a substrate thickness with which the maximum tensile stress σtmax becomes the largest under each scribe condition. The substrate thickness with which σtmax becomes the largest is obtained at a faster scribe velocity for thinner glass substrate and at slower scribe velocity for thicker glass substrate. Owing to these relations, the crack depth also has almost the same tendency as σtmax. 相似文献
88.
Pseudomonas aeruginosa as a model microorganism for investigation of chemotactic behaviors in ecosystem 总被引:1,自引:0,他引:1
Kato J Kim HE Takiguchi N Kuroda A Ohtake H 《Journal of Bioscience and Bioengineering》2008,106(1):1-7
Motile bacteria sense changes in the concentration of chemicals in environments and respond in a behavioral manner. This behavioral response is called chemotaxis. Bacterial chemotaxis can be viewed as an important prelude to metabolism, prey-predator relationships, symbiosis, infections, and other ecological interactions in biological communities. Genome analysis reveals that a large number of environmental motile bacteria possess a number of genes involved in chemosensing and chemotatic signal transduction. Pseudomonas aeruginosa has a very complex chemosensory system with more than 20 chemotaxis (che) genes in five distinct clusters and 26 chemoreceptor (methyl-accepting chemotaxis protein [mcp]) genes. Among the 26 MCPs of P. aeruginosa, nine have been identified as MCPs for amino acids, inorganic phosphate, oxygen, ethylene, and volatile chlorinated aliphatic hydrocarbons, whereas 3 MCPs were demonstrated to be involved in biofilm formation and biosynthesis of type IV pilus. Six che genes are essential for chemotactic responses, while genes in Pil-Chp cluster and Wsp cluster are involved in type IV pilus synthesis and twitching motility and biofilm formation, respectively. P. aeruginosa, with its complex chemotaxis system, is a better model microorganism for investigating ecological aspects of chemotaxis in environmental bacteria than Escherichia coli and Salmonella enterica serovar Typhimurium, which possess a relatively simpler chemotaxis system. 相似文献
89.
Noboru Owada Daisuke Tsuji Kenji Suyama 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(1):30-36
In this paper, we present a stable sound source tracking method based on two updating algorithm. In the method, an eigenvector spanning the signal subspace is updated by using the Projection Approximation Subspace Tracking (PAST) algorithm without the eigen‐decomposition of a correlation matrix. Then, a constrained minimization problem is formulated taking into account the stability, and the solution is determined successively by applying the Interior Point Least Square (IPLS) algorithm. As a result, stable tracking can be achieved without the peak search of a MUltiple SIgnal Classification (MUSIC) spectrum, which often requires enormous computational costs because many complex multiplying operations are involved. Several experimental results in real room environments have demonstrated the high accuracy and the low computational costs of the proposed method. © Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
90.