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132.
This paper presents a robustness analysis of the optimal solution of the step tracking problem in a one-degree of freedom control architecture, for the discrete-time multivariable (MIMO) case. It is shown that the resulting closed loop becomes arbitrarily fragile, i.e. the sensitivity peak becomes arbitrarily large, for certain reference directions. The cause of this problem is that the optimal controller depends on the reference direction. The paper shows that this dependence can be eliminated with an alternative formulation of the optimal problem where the cost is averaged over all reference directions. 相似文献
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134.
A detection-theoretic analysis of the auditory localization of dual-impulse stimuli is described, and a model for the processing of spatial cues in the echo pulse is developed. Although for over 50 years "echo suppression" has been the topic of intense theoretical and empirical study within the hearing sciences, only a rudimentary understanding of its mechanisms has emerged. In this article, psychometric functions and results from matching studies are used in developing a model that specifies the perceived position of the echo pulse as a normal deviate, with an expectation that is a logistic function of the echo delay and a variance that depends on interaural time difference. Loss of information in the echo event is quantified as a decline in the efficiency with which the binaural system receives information from the lag impulse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
135.
It is necessary to determine the accurate reflectance of painted surfaces for the review of paint finishes by computer graphics (CG) before actual painting of the exterior color of automobiles, and for quality control during production and inspection processes. We have optimized a method for measuring reflectance by using a statistical technique. We have found that the reflectance of a painted surface is best measured at an incident angle of 60° and at five aspecular angles of 10°, 18°, 28°, 40°, and 90°. Our method makes it possible to accurately reproduce reflection characteristics of paint finishes containing special flake pigments, such as pearl mica. Also it was proved that our method can apply not only to solid and metallic coatings but to all painted surfaces. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 275–282, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20125 相似文献
136.
星间激光通信技术进展与趋势 总被引:3,自引:3,他引:0
较详细地评述了目前国外卫星间光通信技术研究的现状.根据关键单元技术的进展情况,总结了未来星间光通信系统的发展趋势。 相似文献
137.
随着现代军用通信网络的发展与进步,第三代高频自动链路建立协议(Third-generation HF Automatic Link Establishment)将逐渐取代现有的第二代协议。首先从CSMA机制、Dwell—Groups技术、Multi—Slot技术等方面概略地介绍了3G-ALE技术。然后在同步工作模式下,将Dwell—Groups技术、Multi—Slot技术应用在协议当中进行了对比仿真,并分析了Dwell—Groups技术、Multi—Slot技术对3G-ALE系统性能的影响。 相似文献
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139.
复杂不规则刚体转动惯量的测试原理和方法 总被引:6,自引:0,他引:6
为了测量复杂不规则刚体转动惯量,采用时间常数法,通过A/D卡PS2129的定时/计数器8253高精度测速、计时,能较好地应用于测量转动惯量。 相似文献
140.
Docherty Nancy M.; Cohen Alex S.; Nienow Tasha M.; Dinzeo Thomas J.; Dangelmaier Ruth E. 《Canadian Metallurgical Quarterly》2003,112(3):469
This study examined the degree to which different types of communication disturbances in the speech of 48 schizophrenia patients and 28 controls were variable and state related versus stable and traitlike. Clinically rated formal thought disorder and 5 types of referential disturbance showed substantial stability within participants over time. The sixth type of referential disturbance, the vague reference, was not stable over time. Formal thought disorder was associated with the severity of core psychotic symptoms in patients, whereas referential disturbances showed little or no association with positive or negative symptom severity. Furthermore, changes in psychotic symptoms over time were accompanied by corresponding changes in formal thought disorder but not referential disturbances. These results support the idea that some types of referential disturbances are traitlike and may be reflective of vulnerability as well as manifest illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献