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81.
The original interpretation of the constructive set theory CZF in Martin-Loef‘s type theory uses the‘extensional identity types’.It is generally believed that these‘types’do not belong to type theory.In this paper it will be shown that the interpretation goes through without identity types.This paper will also show that the interpretation can be given in an intensional type theory.This reflects the computational nature of the interpretation.This computational aspect is reinforced by an ω-Set moel of CZF.  相似文献   
82.
A new minimum zone method for evaluating flatness errors   总被引:1,自引:0,他引:1  
A new minimum zone method for flatnes error analyis is proposed in this article. Based on the criteria for the minimum zone solution and strict rules for data exchange, a simple and rapid algorithm, called the control plane rotation scheme, is developed for the flatness analysis of a flat surface. Experimental work was performed, and some examples are given in terms of the minimum zone and least-squares solutions.  相似文献   
83.
We have used spectroscopic ellipsometry to perform real-time monitoring during metalorganic chemical vapor deposition growth of AlGaAs (on GaAs) and InGaAs (on GaAs and InP). Optical constants for these materials were obtained up to growth temperatures of 600 to 700°C. This information permits real-time extraction of composition and layer thickness from the raw ellipsometric data at sample rates on the order of 0.5 Hz. We describe closed-loop control of composition and total layer thickness on AlGaAs-based structures, including Bragg reflectors. In-situ data obtained on double-heterostructure quantum-well laser structures demonstrate that spectroscopic ellipsometry is an extremely powerful monitoring and quality-control tool, giving important real-time information on complex structures that would be difficult and time-consuming to obtain after growth.  相似文献   
84.
This paper presents a highly stable steady-state torque control system with a feedback of a secondary current signal. The torque control system is constructed with a feedback of the secondary current (I2) signal using a quick response magnetic-field sensor constructed with an amorphous core multivibrator bridge, which can solve the secondary resistance change problem for temperature variation in the IM. Moreover, we added a state feedback to the system to improve the response speed for the unit step function of a torque order. The I2 sensor method has advantages especially at a low-speed range, in which conventional method using an integrator shows control errors.  相似文献   
85.
文章给出n-维超立方体网络的容错路径选择算法,该算法具有自适应性,可以防止死锁和活锁现象的发生,应用该算法,可求出一条基于安全优先策略的可行最短路径。  相似文献   
86.
离散事件动态系统的代数模型及其控制器的分析计算   总被引:4,自引:2,他引:2  
本文在离散事件动态系统的Petri网图形描述的基础上建立了相应的代数模型,该模型可以用来计算无竞争无回路Petri网的“最大状态”;该“最大状态”的计算在本文给出的动态反馈控制器中得到了应用。  相似文献   
87.
Functional neuroimaging suggests that limbic regions of the medial frontal cortex may be abnormally active in individuals with depression. These regions, including the anterior cingulate cortex, are engaged in both action regulation, such as monitoring errors and conflict, and affect regulation, such as responding to pain. The authors examined whether clinically depressed subjects would show abnormal sensitivity of frontolimbic networks as they evaluated negative feedback. Depressed subjects and matched control subjects performed a video game in the laboratory as a 256-channel EEG was recorded. Speed of performance on each trial was graded with a feedback signal of A, C, or F. By 350 ms after the feedback signal, depressed subjects showed a larger medial frontal negativity for all feedback compared with control subjects with a particularly striking response to the F grade. This response was strongest for moderately depressed subjects and was attenuated for subjects who were more severely depressed. Localization analyses suggested that negative feedback engaged sources in the anterior cingulate and insular cortices. These results suggest that moderate depression may sensitize limbic networks to respond strongly to aversive events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
This is an outline of research in neural networks for feedback control done since the mid 1990s at the Automation and Robotics Research Institute (ARRI) of The University of Texas at Arlington (UTA). It shows how the developments of Intelligent Control Systems based on neural networks have followed three main generations. This statement provides a short, broad-brush perspective on the development of intelligent neural feedback controllers.  相似文献   
89.
在详细分析料坯在水箱内冷却热过程特点的基础上,提出了前馈和反馈相结合的水流量优化控制策略,并将该策略应用于宝钢线材厂控冷轧线上。实际运行结果表明:该策略能够合理地控制水箱水流量,从而保证了线材水箱出口处的温度满足工艺要求,大大提高了线材成品的质量。所做工作对国内同类企业有重要的意义。  相似文献   
90.
Although increasing feedback specificity is generally beneficial for immediate performance, it can undermine certain aspects of the learning needed for later, more independent performance. The results of the present transfer experiment demonstrate that the effects of increasing feedback specificity on learning depended on what was to be learned, and these effects were partially mediated through the opportunities to learn how to respond to different task conditions during practice. More specific feedback was beneficial for learning how to respond to good performance and detrimental for learning how to respond to poor performance. The former relationship was partially mediated by feedback specificity's effect on learning opportunities during practice. The results have implications for designing feedback interventions and training to maximize the learning of various aspects of a task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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