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991.
Study on the Fuzzy COntrol Strategy of Automobile with CVT 总被引:3,自引:0,他引:3
In order to study the dynamic characteristics of automobile with a CVT system, a bond graph analysis model of continuously variable transmission is established.On the base of the simulation state space equations that are established with bond graph theory,a fuzzy control strategy with an expert system of starting process has been introduced.Considering uncertain system parameters and exterior resistance disturbing,the effect of the profile of membership function and the defuzzification algorthm on the capacity of the fuzzy controller has been studied.The result of simulation proves that the proposed fuzzy controller is effective and feasible,Such controller has been employed in the actual control and has proved practicable.The study lays a foundation for design of the fuzzy controller for automobile with a CVT system. 相似文献
992.
The subject of this work is the assessment on the stability of an excavated high slope in order to insure the security of the building site adjacent to the slope,which is frequently encountered in town construction in mountainous areas due to terrain limit.On the base of some typical engineering cases in Chongqing,several crucial problems on security assessment of building site adjacent to an excavated high slope,including the natural geological conditions and man-destroyed degree,engineering environment,potential failure pattern of the high slope,calculation parameters and analysis methods,are roundly discussed.It is demonstrated that the conclusion of security assessment can be determined according to the aspects above-mentioned,and the security assessment is one of the fundamental data to insure the safety of the related construction,site and buildings. 相似文献
993.
R. J. Auge 《Learning & behavior》1977,5(2):117-123
Pigeons received food for responding on a fixed-interval 32-sec schedule divided into three equal parts, each correlated with a distinctive, response-independent, visual stimulus. Response rate was very low during the first two thirds of the interval but high during the terminal third. When a response-dependent brief stimulus correlated with the terminal third was arranged for each response in the presence of the stimuli correlated with the first two thirds, response rate was enhanced, especially in the middle third. However, response rate was suppressed when each response in the presence of the stimulus correlated with the final third produced a brief stimulus correlated with the initial third. A similar suppressive effect occurred when each response produced a brief stimulus correlated with the middle third. Response suppression decreased over successive response-dependent brief-initial-stimulus manipulations. The results were interpreted in terms of reinforcement, punishment, and discriminative stimulus control by visual stimuli correlated with parts of a fixed-interval schedule. 相似文献
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In this paper, we study an adaptive random search method based on continuous action-set learning automaton for solving stochastic optimization problems in which only the noise-corrupted value of function at any chosen point in the parameter space is available. We first introduce a new continuous action-set learning automaton (CALA) and study its convergence properties. Then we give an algorithm for optimizing an unknown function. 相似文献
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1000.
To compare the effectiveness of training in heat and in sweat clothing in cool conditions on improving heat tolerance, two groups of active subjects (n = 6 in each) performed an interval running heat-tolerance test before and after a 7-day experimental treatment. On each treatment day the subjects attempted to complete 4 x 15 min interval treadmill running periods (a 7.5 s effort every 30 s, on 15 km h-1, 15% grade; the same exercise format as the heat-tolerance test), which were interspersed with 5-min recovery periods (total time each day = 80 min). Group 1 (heat) ran in shorts, socks and shoes in hot humid conditions, and Group 2 (sweat clothing) ran in cool conditions dressed in shorts, socks and T-shirt covered by a polyester-cotton tracksuit, over which was worn 100% nylon spray-proof pants and jacket (cotton lined) with an acrylic cloth bobble hat (beanie) on the head. Both groups displayed changes typical of heat acclimatization over the 7-day period, with significant decreases in final rectal temperature (Tr) and heart rate (HR) being evident, but no change in sweat loss. Mean skin temperature (Tsk) was similar in both groups during the training sessions (heat group: 34.8-35.7 degrees C; sweat clothing group 34.9-35.5 degrees C). After the heat-tolerance test, both groups had significantly lower Tr, Tsk and HR values than before, and sweating sensitivity (g m-2 h-1 degrees C rise in Tr) was significantly increased. There was only one significant difference between the two groups (Tsk, 20th min value). It was concluded that training in sweat clothing in cool conditions can provide the same improvements in heat tolerance as training in hot humid conditions where a fixed exercise intensity and duration are used. 相似文献