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951.
Consideration is given to pulse control problems for the tube of trajectories of the linear differential system under incomplete information on the initial data. Apart from the ordinary requirement for boundedness of variation, a special constraint of the ellipsoidal type is imposed on control actions; at this constraint, vectors of jumps of generalized controls belong to the specified ellipsoid of the corresponding finite-dimensional space. The dependence of the variation of optimal pulse control that solves the control problem for the tube of trajectories on parameters of the ellipsoidal constraint on admissible controls is studied.  相似文献   
952.
The results of investigations performed by specialists at Research and Design Institute of Electrical Technology together with other enterprises, institutes, and organizations concerning the formulation of a strategy for the development of nuclear power in Russia in the first half of the 21st century are presented. The individual stages of the work, key assumptions, ideas, and recommendations, on which the strategy is based, the initiatives which the President of the Russian Federation advanced at the millennium summit held at the United Nations, and the international INPRO project initiated by Russia are examined. It is concluded that innovative development and a transition to building as quickly as possible nuclear power objects that meet the requirements and demands of the new century are necessary. __________ Translated from Atomnaya énergiya,Vol. 103, No. 1, pp. 5–15, July, 2007.  相似文献   
953.
A semiconductor-based master-oscillator power-amplifier operating at 977 nm is demonstrated to emit more than 10 W continuous wave in a nearly diffraction limited beam with a narrow spectral bandwidth. The device consists of a distributed Bragg reflector laser and a flared amplifier monolithically integrated on a single chip  相似文献   
954.
955.
956.
Scholars who study close relationships often measure the same concept with both observational ratings and questionnaire items. In studies where this has been done, the correlations between the two measures have often been low, and one reason may be a "context by measurement" confound. Observational ratings are usually based on behaviors during a specific task, whereas most questionnaire responses are based on a broader context such as "during the past month." In 2001, a total of 292 young couples were videotaped during a discussion task and asked to report on their own behavior and that of their partner during the discussion task and during the past month. The data were configured as a multitrait, multimethod matrix, and the magnitudes of the correlations were estimated with confirmatory factor analysis. The resulting correlations between observer ratings and questionnaire reports of hostile behavior during the videotaped discussion were roughly twice the magnitude of the correlations between observer rating and questionnaire reports during the past month. This suggests that the correspondence between behavioral categories and the content of questionnaire items is greater than previous studies have indicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
957.
We consider the problem of common linear copositive Lyapunov function existence for positive switched linear systems. In particular, we present a necessary and sufficient condition for the existence of such a function for switched systems with two constituent linear time-invariant systems. Several applications of this result are also given.  相似文献   
958.
For the system with a small parameter under nonlinearities, consideration was given to the problem of optimal speed. The values of the multivariable control actions are bounded in the Euclidean norm. The theorem of existence and asymptotic properties of the solution of this problem was proved. It underlies the algorithm to construct asymptotic arbitrary-order approximations to the optimal control.  相似文献   
959.
The basic design solutions and characteristics of the VBéR-300 reactor system for the power-generating units of 150–300 MW(e) nuclear power plants and regional nuclear heat-and-electricity plants are described. The reactor system implemented as a unit is based on the technologies and solutions used for marine nuclear power systems, which have been corroborated by experience in operating nuclear-powered icebreakers. The technical-economic advantages of floating power-generating units are substantiated. __________ Translated from Atomnaya énergiya, Vol. 102, No. 1, pp. 35–39, January, 2007.  相似文献   
960.
Using qualitative data, Blom and Monk (2003) derived a theory of why people choose to personalise the appearance of their PCs and mobile phones. This paper describes some quantitative data that provide some support for, and some modifications to, the theory. Individuals having personal home pages were recruited to fill in a questionnaire that assesses dispositions to personalise and its effects. In addition the 82 home pages were inspected to assess the extent of personalisation. This correlated significantly with the dispositions 'Frequency of Use' and 'Knowledge of Personalisation'. The questionnaire items corresponding to effects were factor analysed. A four-factor solution suggested item groupings similar, but not identical, to those used in the theory. There are significant positive correlations between the extent of personalisation and cognitive effects and enduring emotional effects. The value of quantitative data for confirming and refining a qualitative theory is discussed.  相似文献   
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