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排序方式: 共有358条查询结果,搜索用时 15 毫秒
1.
2.
Cooperative behavior of various agents in dynamic environment 总被引:5,自引:0,他引:5
Akihide Hiura Toshiya Kuroda Nobuhiro Inuzuka Ken-ichi Itoh Masashi Yamada Hirohisa Seki Hidenori Itoh 《Computers & Industrial Engineering》1997,33(3-4):601-604
The multi-agent model is a model in which agents with limited ability cooperate each other to accomplish a goal. In this paper, we introduce a multi-agent model in which agents are created to imitate real ants. There are two different type of agents, each type of which has a particular task. We designed agents to communicate each other by using pheromone considering noise. On this model, we observed cooperative behavior of agents and evaluated conditions to make an order of behavior in the model. 相似文献
3.
We clarified the roles of IL-1 beta in peripheral neural regeneration after axotomy in a three-dimensional collagen gel culture system ranging from a single neurone to a dorsal root ganglion (DRG) explant with its associated nerve bundles. Application of 30 U/ml IL-1 beta to the culture systems clearly enhanced neural regeneration. This regeneration was evident in transected nerve terminals of DRG explants with or without associated nerve bundles, but not in dissociated single neurones. Neural survival was not affected by IL-1 beta in any of these culture systems. These results suggest that IL-1 beta stimulates surrounding non-neuronal cells to secrete neurotrophic factors, thus enhancing neurite regeneration from transected nerve terminals in cultured adult DRG explants. 相似文献
4.
K Ueda K Kitagawa M Kadoya O Matsui T Takashima T Yamahana 《Canadian Metallurgical Quarterly》1995,20(6):547-553
BACKGROUND: Most hepatocellular carcinomas (HCCs) are hypervascular and arise in the liver with chronicity. Spiral volumetric CT (SVCT) is a new rapid-scan technique that offers whole-liver scanning during the arterial-dominant phase. The main aim of the present study is to evaluate the detectability of hypervascular HCC with SVCT as compared with ultrasonography (US) and magnetic resonance (MR) imaging. METHODS: Forty-three hypervascular HCCs in 512 patients with chronic liver disease were examined with US, precontrast SVCT, postcontrast SVCT during the arterial-dominant phase (CT-ADP) and during the equivalent-phase (CT-EP) noncontrast MR imaging and angiography including SVCT during arteriography and arterial portography. Angiographic and follow-up findings were used as the gold standard if the lesion was not confirmed histologically. RESULTS: The sensitivity was 61% with precontrast CT, 84% with CT-ADP, 58% with CT-EP, 70% with US, 72% with MR, and 95% with the combination of these five modalities. Five HCCs (12%) were detected with only CT-ADP. The vascularity of HCC was correctly evaluated as hypervascular in 38 nodules (88%) with the combination of precontrast CT and CT-ADP. CONCLUSIONS: We suggest that the combination of precontrast SVCT and CT-ADP is an essential modality to screen for HCC in patients with chronic liver disease. CT-EP did not contribute to the detection of hypervascular HCC. 相似文献
5.
Plane deformation of anisotropic beams with narrow rectangular cross sections exhibits coupling of stretching, bending and transverse shearing. For anisotropic cantilever beams with a stiff end-cap under end forces and an end couple, assessments were made for approximate solutions by comparing these with numerically exact finite element (FE) solutions. Specific attention is given to point-wise or approximate satisfaction of the end-fixity conditions. As approximate methodologies, (i) the elementary polynomial form of Airy's stress function for the plane stress problem in a rectangular region, (ii) a Timoshenko-type beam theory, and (iii) the Bernoulli-Euler beam theory were selected. Among these, only the polynomial form of Airy's stress function violates the point-wise end-fixity conditions. Both the polynomial Airy stress function and the Timoshenko-type beam theory successfully model the effects of transverse shear deformation and the coupling of stretching and transverse deflection. Analytical solutions demonstrate that the normal shear coupling effect increases linearly with the thickness-to-span ratios in axial normal stress and axial displacement, while the coupling manifests quadratically in transverse displacement. The comparison of end displacements with the numerically exact FE solutions indicates that the polynomial form of Airy's stress function is no better than the Timoshenko-type beam theory. Similar conclusions were reached for the problem of uniformly loaded cantilever beams. It has been found that the accurate prediction of the deformation of thick anisotropic beams with significant normal-shear coupling requires the use of higher order theories. 相似文献
6.
Hiroyuki?Y.?SuzukiEmail author Hidenori?Kuroki 《Metals and Materials International》2004,10(2):185-191
A new compacting method for powder materials is presented. High-Speed Centrifugal Compaction Process (HCP) utilizes centrifugal
force of about 10,000 g for the compaction. HCP is suitable for net shape compaction of fine sub-micron and nano-powders.
HCP possesses a unique compacting mechanism that is different from other colloidal processes including Pressure Casting (PC),
and has a number of useful characteristics. HCP has a higher compacting speed than PC, wide applicability for net shape formation,
as well as a defect removing function. Because of homogeneous and flawless green microstructure, HCP alumina shows superior
sinterability and higher strength and hardness than most of other aluminas.
This article is based on a presentation made in the symposium “The 3rd KIM-JIM Joint Symposium on Advanced Powder Materials“,
held at Korea University, Seoul, Korea, October 26–27, 2001 under auspices of The Korean Institute of Metals and Materials
and The Japan Institute of Metals. 相似文献
7.
CdS clusters encapsulated in Y-type zeolite were prepared by a novel technique with non-aqueous systems. The mechanical mixture of CdCl2· 2.5H2O crystal with Y-type zeolite was heated at 773 K, followed by the H2S treatment at 373 K, resulting in the formation of CdS clusters with the size <2.3 nm. 相似文献
8.
Imoto Taiji; Ueda Tadashi; Tamura Tomohiro; Isakari Yoshimasa; Abe Yoshito; Inoue Makoto; Miki Takeyoshi; Kawano Keiichi; Yamada Hidenori 《Protein engineering, design & selection : PEDS》1994,7(6):743-748
Mutations around His15 which lie far away from the active site,stimulated glycol chitin activity of lysozyme at physiologicaltemperature. Del-Argl4Hisl5 lysozyme, a mutant lysozyme whoseArgl4 and Hisl5 were deleted together, and has the highest activityamong these mutant lysozymes, had a similar binding abilityto a trimer of N-acetyl-glucosamine, a substrate analogue, relativeto native lysozyme. This suggests that the increased activitywas due to an increased kcat in the catalysis reaction. TheH-D exchange rate of the N-1 proton in the Trp63 which is locatedin the active site cleft, was enhanced in the Del-Argl4Hisl5lysozyme, while 2-D proton NMR analysis revealed no conformationalchange around Trp63. We conclude that some sort of fluctuationat the active site might be required for the manifestation ofactivity. This theory is supported by the finding that the Del-Argl4Hisl5lysozyme showed a shift in temperature dependency of activityto lower temperatures compared with that of native lysozyme. 相似文献
9.
Maeda Yoshitake; Koga Hiroshi; Yamada Hidenori; Ueda Tadashi; Imoto Taiji 《Protein engineering, design & selection : PEDS》1995,8(2):201-205
To increase the folding yield of concentrated reduced lysozyme,we developed a renaturation method by means of dialysis fromconcentrated urea with redox agents. After lysozyme was incubatedin the reducing buffer (8 M urea solution) with oxidized glutathione,renaturation of reduced lysozyme was started by dialysis againstthe dialyzing buffer containing 8 M urea with redox agents.The urea concentration of the dialyzing bottle was graduallydiluted with dialyzing buffer without urea at a flow rate of0.1 ml/min by high pressure pump. Using this systematic dialysis,a concentration as high as 5 mg/ml of reduced lysozyme couldbe renaturated in 80% yield, while the folding yield was <5%even at a concentration of 1 mg/ml using a conventional rapiddilution method [Goldberg et al. (1991) Biochemistry, 30, 27902797].Therefore, it was concluded that gentle removal of urea fromdenatured proteins, dissolved in concentrated urea solution,by means of dialysis should be useful to renature denaturedproteins effectively. 相似文献
10.
Hidenori Okuzaki Kosuke Hosaka Hiroki Suzuki Takamichi Ito 《Sensors and actuators. A, Physical》2010,157(1):96-99
Temperature dependence of water vapor sorption and electro-active polymer actuating behavior of free-standing films made of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) was investigated by means of sorption isotherm and electromechanical analyses. The non-porous PEDOT/PSS film, having a specific surface area of 0.13 m2 g?1, sorbed water vapor of 1080 cm3(STP) g?1, corresponding to 87 wt%, at relative water vapor pressure of 0.95. A temperature rise from 25 °C to 40 °C lowered sorption degree, indicative of an exothermic process, where isosteric heat of sorption decreased with increasing water vapor sorption and the value reached 43.9 kJ mol?1, being consistent with the heat of water condensation (44 kJ mol?1). Upon application of 10 V, the film underwent contraction of 2.46% at 5 °C caused by desorption of water vapor due to Joule heating, which slightly decreased to 2.10% at 45 °C. The speed of contraction was one order of magnitude faster than that of expansion and less dependent on the temperature since water vapor sorbed in the film were forced to desorb by Joule heating. In contrast, the higher the temperature the faster the film expansion because diffusion coefficient increased as the temperature became higher. 相似文献