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11.
Jing-Sin Liu King Yuan Wei-Sung Lin 《Automatic Control, IEEE Transactions on》1989,34(7):767-770
The minimum-fuel control problem is investigated for a class of multiinput affine nonlinear systems whose associated Lie algebra is nilpotent. After preliminary notions and definitions are presented, emphasis is on the solution to the optimal control problem of the Lie algebra generated by certain system vector fields is nilpotent. Consequences of the maximum principle are deduced for such systems 相似文献
12.
13.
D. M. Van Wie D. G. Drewry Jr. D. E. King C. M. Hudson 《Journal of Materials Science》2004,39(19):5915-5924
Hypersonic flight powered by airbreathing engines offers the potential for faster response time at long ranges, and reduced cost for access-to-space. In the present paper the operating environment of typical hypersonic vehicles are discussed, including results for the radiation equilibrium wall temperature of external vehicle surfaces and the flow properties through three sample engines spanning the range of hydrocarbon-fueled Mach 4-8 flight and hydrogen-fueled flight at speeds up to Mach 17. Flow conditions at several locations through the sample engines were calculated to provide indications of the required operating flow environment. Additional system consideration such a seals, joints, vehicle integration and in-service engineering are addressed. 相似文献
14.
Wei-Cheng Lin Tsung-Chien Wu Yi-Hung Tsai Long-Jei Du Ya-Chin King 《Electron Devices, IEEE Transactions on》2005,52(7):1478-1483
Circuit reliability of class-E and class-A power amplifiers is investigated based on a newly developed degradation subcircuit model. Measured degradation characteristics on the fabricated circuits agree well with the simulation predictions. Using this model, we have found that the class-E amplifier degrades faster than a class-A amplifier, due to a much higher stress level during switching. With a drastic decrease of PAE, a shorter lifetime is expected for a class-E amplifier. 相似文献
15.
Digant Gupta Christopher G Lis Sadie L Dahlk Jessica King Pankaj G Vashi James F Grutsch Carolyn A Lammersfeld 《Nutrition journal》2008,7(1):19
Background
Bioelectrical Impedance (BIA) derived phase angle is increasingly being used as an objective indicator of nutritional status in advanced cancer. Subjective Global Assessment (SGA) is a subjective method of nutritional status. The objective of this study was to investigate the association between BIA derived phase angle and SGA in advanced colorectal cancer. 相似文献16.
Xin Sun Qiang Lu Moroz V. Takeuchi H. Gebara G. Wetzel J. Shuji Ikeda Changhwan Shin Tsu-Jae King Liu 《Electron Device Letters, IEEE》2008,29(5):491-493
A tri-gate bulk MOSFET design utilizing a low-aspect-ratio channel is proposed to provide an evolutionary pathway for CMOS scaling to the end of the roadmap. 3-D device simulations indicate that this design offers the advantages of a multi-gate FET (reduced variability in performance and improved scalability) together with the advantages of a conventional planar MOSFET (low substrate cost and capability for dynamic threshold-voltage control). 相似文献
17.
SA King 《Canadian Metallurgical Quarterly》1996,60(6):347-354
The following are things I have learned, routines my nurses have brought to me, or that we have developed together during 11-years existence with amyotropic lateral sclerosis (ALS) eight of which have been burdened by ALS induced quadriplegia and ventilator dependence. Items are listed, not in order of importance, which may vary from individual to individual, but alphabetically. Some are unique. Some commonplace. All are useful and many are of surprising value. Deviations from common understanding or practice are marked with an asterisk, and practices that can afford significant economies are double asterisked. This is written in an attempt to share with others in the profession lessons I have learned from personal experience--the hard way. 相似文献
18.
We demonstrate multi-emitter Si/GexSi1-x n-p-n heterojunction bipolar transistors (HBT's) which require no base contact for transistor operation. The base current is supplied by the additional emitter contact under reverse bias due to the heavy doping of the emitter-base junction. Large-area HBT test structures exhibit good transistor characteristics, with current gain β≈400 regardless of whether the base current is supplied by a test base electrode or one of the emitter contacts. These devices have enhanced logic functionality because of emitter contact symmetry. Since device fabrication does not require base electrode formation, the number of processing steps can be reduced without significant penalty to HBT performance 相似文献
19.
Wideband chirp measurement technique for high bit rate sources 总被引:1,自引:0,他引:1
A Mach Zehnder (MZ) interferometer has been used as an optical discriminator to measure the time-resolved frequency chirp of an optical source 相似文献
20.
The behavioral disturbances of 16 nursing home patients with a history of sundowning behaviour and dementia were treated with light therapy instead of psychopharmacological medication. After the withdrawal of the before established medication a very individual, heterogenous deterioration of the symptoms was noted. A significant improvement of the behaviour was not found by light therapy in any patient. The problems in practical handling and possible consequences of further investigation are discussed. 相似文献