排序方式: 共有13条查询结果,搜索用时 203 毫秒
1.
Robert Shiurba Tatsuo Hirabayashi Shin Kiyokawa Akimasa Fukui Yuko Miyanaga Issey Kojima Makoto Asashima 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1999,23(12):2041
In most ectotherms, environmental temperature has differential effects on growth and differentiation. For example, amphibian size at maturity decreases with increasing temperature. To address how radiant heat in the form of far-infrared radiation (FIR) may affect development of the aquatic ectotherm Xenopus laevis, we continuously irradiated swimming larvae as they developed into young adults. Here we report evidence that FIR promotes growth of these organisms in an aqueous environment. 相似文献
2.
3.
A new open-loop adaptive-array system with excellent transient behavior is presented. The system is constructed of analog circuits and determines complex weights without using the feedback of the array output. The performance attainable with the system is described in detail. It is shown that the convergence rate of the system does not depend on a noise environment but is determined by the time constant of the low-pass filters included. Moreover, it is shown that although the steady-state performance is quite good when the interference sources differ widely in signal strength, the steady-state performance can be far below optimum when two or more interference sources are present at roughly equal power levels. 相似文献
4.
Mono Shimizu Katsuya Itoh Hitoshi SatoTadayuki FujiiKen-ichi Okamoto Shigehiko TakaokaKotaro ShiinaYoshihiro Nakamura 《Acta Astronautica》1999,44(7-12):345-351
One potentially attractive propulsion concept offering significant payload gains for orbit transfer from LEO to higher orbits, station keeping and attitude control of spacecraft is thermal propulsion using light gas (typically hydrogen) as propellant and various kinds of heat energy. Solar Thermal Propulsion (STP) is a typical thermal propulsion with high Isp (500 – 1,000 s) in an appropriate thrust magnitude range and provides possibly much less space pollution than conventional chemical propulsion.
This paper presents the test results of a 30 mm dia. (medium-sized) windowless type of single crystal Mo thruster for orbit transfer of 50 kg class microsatellites. The cavity dia. is 20 mm, double the size of the previous model, and can apply to a primary solar reflector of up to 3.5 m dia., which is the maximum size containable in the H-II rocket fairing without segmentation. The performed mission analyses indicate that this size of STP is suitable to orbit transfer of 50 kg class microsatellites, such as LEO to GEO, or only multiple apogee kicks from GTO to GEO or deep space missions. 相似文献
5.
K. Enya T. Kotani K. Haze K. Aono T. Nakagawa H. Matsuhara H. Kataza T. Wada M. Kawada K. Fujiwara M. Mita S. Takeuchi K. Komatsu S. Sakai H. Uchida S. Mitani T. Yamawaki T. Miyata S. Sako T. Nakamura K. Asano T. Yamashita N. Narita T. Matsuo M. Tamura J. Nishikawa E. Kokubo Y. Hayano S. Oya M. Fukagawa H. Shibai N. Baba N. Murakami Y. Itoh M. Honda B. Okamoto S. Ida M. Takami L. Abe O. Guyon P. Bierden T. Yamamuro 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
6.
Y H Itoh A Sugai I Uda T Itoh 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2001,28(4):719-724
Living organisms on the Earth which are divided into three major domains--Archaea, Bacteria, and Eucarya, probably came from a common ancestral cell. Because there are many thermophilic microorganisms near the root of the universal phylogenetic tree, the common ancestral cell should be considered to be a thermophilic microorganism. The existence of a cell is necessary for the living organisms; the cell membrane is the essential structural component of a cell, so its amphiphilic property is vital for the molecule of lipids for cell membranes. Tetraether type glycerophospholipids with C40 isoprenoid chains are major membrane lipids widely distributed in archaeal cells. Cyclization number of C40 isoprenoid chains in thermophilic archaea influences the fluidity of lipids whereas the number of carbons and degree of unsaturation in fatty acids do so in bacteria and eucarya. In addition to the cyclization of the tetraether lipids, covalent bonding of two C40 isoprenoid chains was found in hyperthermophiles. These characteristic structures of the lipids seem to contribute to their fundamental physiological roles in hyperthermophiles. Stereochemical differences between G-1-P archaeal lipids and G-3-P bacterial and eucaryal lipids might have occurred by the function of some proteins long after the first cell was developed by the reactions of small organic molecules. We propose that the structure of lipids of the common ancestral cell may have been similar to those of hyperthermophilic archaea. 相似文献
7.
This article analyses the rapid economic advancement of the Pacific Basin area, and discusses its future potential. Common efforts in space utilization can integrate the area, and overcome the wide diversity of political, economic and social structures. Aspects of communications, space remote sensing and space-based materials processing are examined and forecasts are made for the future role of the Pacific Basin in these areas. A populated Orbital Space City will be necessary to further space utilization. To support future activities in space, a Pacific Spaceport and a Pacific Space Centre are proposed, which would lead to the development of several ‘New Industrialized Areas’ in the age of the Solar Power Satellite. Estimates are made of the amount of electricity which will be required. 相似文献
8.
Robert Shiurba Tatsuo Hirabayashi Shin Kiyokawa Akimasa Fukui Yuko Miyanaga Issey Kojima Makoto Asashima 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1999,23(12):2041-2044
In most ectotherms, environmental temperature has differential effects on growth and differentiation. For example, amphibian size at maturity decreases with increasing temperature. To address how radiant heat in the form of far-infrared radiation (FIR) may affect development of the aquatic ectotherm Xenopus laevis, we continuously irradiated swimming larvae as they developed into young adults. Here we report evidence that FIR promotes growth of these organisms in an aqueous environment. 相似文献
9.
Pilot uncertainty in aircraft response under automatic flight control has triggered aircraft accidents/incidents in the past. This uncertainty compels a pilot to disengage autopilot and switch to manual control. However, the decision to disengage autopilot and when to do it can be difficult: especially if there is not enough time to monitor the cockpit displays, for instance while countering atmospheric turbulence. Against this background, we proposed the “human as a control module” architecture for harmonizing pilot and autopilot controls. The architecture blends pilot maneuver with autopilot control instead of switching between them when simultaneous inputs are given to the aircraft. By automatically adjusting pilot and autopilot control inputs, the architecture avoids overlaps of both control authorities and helps to circumvent the effect of conflicting actions. This paper applies the architecture to the situations of past aircraft incidents which had been caused by the transfer from autopilot control to pilot maneuver after encountering atmospheric turbulence. The effectiveness of the architecture is evaluated via simulation study for the specific incident examples. Furthermore, this paper extends the architecture with an Extended Kalman Filter (EKF) based observer and evaluates its robustness under errors in wind estimation. 相似文献
10.
通过采用时域模技术,FDTD-Diakoptics算法可以用来有效准确地分析复杂的微波集成电路.根据电路的几何结构选定时域模函数,以该时域模函数为基础,建立微波电路的多模电路模型,使用全波时域分析方法求解多模电路对应于各个时域模的时域响应,使用傅里叶变换技术计算时域模函数的冲击响应,从而进一步得到多端口网络模型,使用FDTD-Diakoptics算法对微波电路进行分析.讨论了全波时域方法求解时域模函数时域响应时激励函数的选取原则,讨论了用傅里叶反变换求解时域模函数冲击响应时频带宽度的选取问题.最后本方法被应用于波导滤波器的分析设计. 相似文献