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41.
Guisheng Zhai Shohei Okuno Joe Imae Tomoaki Kobayashi 《Journal of Intelligent and Robotic Systems》2011,63(2):309-322
In this paper, we study a consensus problem for multi-agent systems via dynamic output feedback control. The entire system
is decentralized in the sense that each agent can only obtain output information from its neighbor agents. For practical purpose,
we assume that actuator limitation exists, and require that the consensus be achieved among the agents at a specified convergence
rate. By using an appropriate coordinate transformation, we reduce the consensus problem on hand to solving a strict matrix
inequality, and then propose to use the homotopy based method for solving the matrix inequality. It turns out that our algorithm
includes the existing graph Laplacian based algorithm as a special case. 相似文献
42.
Terui H. Shibazaki T. Ebisawa F. Okuno M. Jinnouchi Y. Kamei S. 《Photonics Technology Letters, IEEE》2009,21(19):1426-1428
In this letter, we have developed a novel technique for improving the temperature stability of an athermal silica-based arrayed-waveguide grating with a resin-filled groove. We compensated for the residual second-order temperature dependence of the passband wavelength using the pressure-induced refractive index change in a resin inserted into the optical paths. Pressure control under the temperature variation was achieved by using a structure composed of an optical fiber piston and bimetal actuators. We demonstrated that the passband wavelength variation was successfully reduced from 0.080 to 0.025 nm in a -40degC - 85degC temperature range, without any insertion loss increase or spectral change. 相似文献
43.
We calculated electronic structures and transport properties of 33 Zintl phase compounds M1M2X (M1, M2 = Li, Na, Mg, K, Ca, Rb, Sr, Ba; X = Si, Ge, As, Se, Sn, Sb, Te, Pb, Bi) having orthorhombic MgSrSi-type (PbCl2-type) structure. These compounds were calculated to be narrow-gap semiconductors or semimetals. By comparison with known thermoelectric materials, our analysis showed that these compounds are promising candidate new thermoelectric materials, when heavily doped with holes or electrons. The weak chemical bonds and the variety in constituent elements indicate the possibility to achieve high thermoelectric figure of merit. 相似文献
44.
Okuno Y.L. Gan K.-G. Chou H.-F. Chiu Y.-J. Wang C.S. Wu S. Geske J. Bjorlin E.S. Bowers J.E. 《IEEE journal of selected topics in quantum electronics》2005,11(5):1006-1014
We present stable polarization of a long-wavelength vertical-cavity surface-emitting laser (LW VCSEL). The polarization control was achieved through growing its active region on a (113)B InP substrate, which was integrated to [001] GaAs-based distributed Bragg reflectors by a wafer-bonding technique. Theoretical investigation showed that to achieve high polarization stability, a large dichroism such as an anisotropic gain is needed. It was also shown that the (113)B and other planes of the (11n) family have asymmetry, which results in asymmetric stress and anisotropic optical gain in a strained multiquantum well. An index-guiding mesa structure was fabricated in an asymmetric shape. The index guiding either enhanced or distracted the polarization stability originating from gain anisotropy, depending on its orientation of the asymmetry, as was confirmed by a statistical summary. Using a VCSEL with an appropriate index-guiding structure, we performed 1-Gb/s modulation and confirmed single polarization under large-signal modulation. 相似文献
45.
The effects of stimulated Raman amplification in an optical fibre on stimulated Brillouin scattering (SBS) are investigated. There is a surprisingly simple and general relationship between the Raman net gain and the change in the SBS threshold power, with almost no dependence on fibre parameters 相似文献
46.
A menu generator for audio visual networks 总被引:1,自引:1,他引:0
An audio visual system can enhance its controllability by an interactive and user-friendly menu through which a user issues commands to control audio visual devices. One of the serious problems encountered in such menu development is that end-user's requirement specifications vary in screen layouts, device configurations and commands contents, and often involves extensive manual programming. We have definedMacroMMenu formally as a tree structure menu system model restricting a menu transition graph, and designed and implemented an automated menu prototyping system which includes a menu generator calledInteractive Proto. UsingInteractive Proto through a visual programming language, end-users themselves, who are usually non-programmers, can easily define menu specification, input this source specification, and the targetMacro Menu is generated automatically. 相似文献
47.
A method for systematically analyzing biochemical reactions in a cell was proposed. One of the characteristic features of biochemical reactions in a cell is that many components are participating and that quite many reactions are taking place. Also bio-separation processes are observed. We applied material-utilization diagrams to systematically grasp such a biochemical process. We used two diagrams. In the first diagram, the change in concentration for each component was presented, whereas in the second diagram, the deviation of each biochemical reaction from the equilibrium condition was displayed. Those diagrams suggested the possibility to improve the biochemical process, since they revealed the exergy losses caused by changes in concentration or biochemical reactions. 相似文献
48.
This is an overview paper of the joint TITAN (Tritium, Irradiation, and Thermofluid for America and Nippon) project of the Japan–USA fusion cooperation program. The objectives, tasks structure, and technical highlights of the TITAN project are presented, as well as the direction of the project toward its end in March 2013. 相似文献
49.
Yukari Totsuka Takashi Higuchi Toshio Imai Akiyoshi Nishikawa Takehiko Nohmi Tatsuya Kato Shuich Masuda Naohide Kinae Kyoko Hiyoshi Sayaka Ogo Masanobu Kawanishi Takashi Yagi Takamichi Ichinose Nobutaka Fukumori Masatoshi Watanabe Takashi Sugimura Keiji Wakabayashi 《Particle and fibre toxicology》2009,6(1):1-11
Background
Recently, manufactured nano/microparticles such as fullerenes (C60), carbon black (CB) and ceramic fiber are being widely used because of their desirable properties in industrial, medical and cosmetic fields. However, there are few data on these particles in mammalian mutagenesis and carcinogenesis. To examine genotoxic effects by C60, CB and kaolin, an in vitro micronuclei (MN) test was conducted with human lung cancer cell line, A549 cells. In addition, DNA damage and mutations were analyzed by in vivo assay systems using male C57BL/6J or gpt delta transgenic mice which were intratracheally instilled with single or multiple doses of 0.2 mg per animal of particles.Results
In in vitro genotoxic analysis, increased MN frequencies were observed in A549 cells treated with C60, CB and kaolin in a dose-dependent manner. These three nano/microparticles also induced DNA damage in the lungs of C57BL/6J mice measured by comet assay. Moreover, single or multiple instillations of C60 and kaolin, increased either or both of gpt and Spi- mutant frequencies in the lungs of gpt delta transgenic mice. Mutation spectra analysis showed transversions were predominant, and more than 60% of the base substitutions occurred at G:C base pairs in the gpt genes. The G:C to C:G transversion was commonly increased by these particle instillations.Conclusion
Manufactured nano/microparticles, CB, C60 and kaolin, were shown to be genotoxic in in vitro and in vivo assay systems. 相似文献50.
Okabe M. Okuno Y. Arakawa T. Tomioka I. Ohno T. Noda T. Hatanaka M. Kuramitsu Y. 《Solid-State Circuits, IEEE Journal of》1989,24(5):1280-1286
A 0.8- mu m CMOS sea-of-gates (SOG) array with first-level wiring channels perpendicular to transistor rows and 40 0K transistors is integrated on a 6*7-mm/sup 2/ chip. Implementation of a 64-bit multiplier shows 60-percent gate utilization and density of 1410 G/mm/sup 2/. The wiring length of the multiplier is 70 percent of that in a conventional SOG.<> 相似文献