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991.
高建舟  单晓 《工业炉》2004,26(6):26-28
对宽厚板坯加热过程中,坯料出炉温度波动较大的现象,进行了较详细的分析,找到了解决这一问题的有效途径。通过优化加热炉生产工艺,提高了板坯加热质量,效果显著。  相似文献   
992.
以识别主砂体为主线的陆相盆地产铀远景评价体系   总被引:4,自引:1,他引:4  
本文通过对前人所做的盆地产铀远景评价的判据进行评述,引入以识别主砂体为主线的陆相盆地产铀远景评价体系。该体系以识别有利主砂体为主线,进行主砂体的成因分析,进而确定主砂体形成的沉积体系,并通过探讨在不同类型盆地的不同演化阶段沉积体系的发育特征,确定不同类型盆地主砂体发育最为有利的时期(即预期找矿目的层),构成一个盆地产铀远景评价体系。此外,还讨论了主砂体沉积之后的构造运动对砂岩铀成矿的影响。  相似文献   
993.
统一混沌系统的脉冲控制与同步   总被引:7,自引:0,他引:7  
对统一混沌系统的脉冲控制稳定性与同步问题进行了理论分析,利用脉冲微分方程理论给出了脉冲控制稳定与同步的充分条件,并对脉冲控制时间间隔的范围作了估计。最后,通过仿真进行了验证。  相似文献   
994.
法国Sofradir公司生产的288×4红外焦平面阵列(IRFPA)具有很高的探测灵敏度,是军用红外系统的理想器件。由于器件本身的结构特点,在使用时需要进行奇偶校正。该电路的控制逻辑比较复杂,实现的方法有三种:用传统的中小规模集成电路实现,这种实现方法难度比较大;用CPLD或FPGA做逻辑,其它部分用中小规模集成电路,这种实现方法布线比较困难;所有电路全部用FPGA实现,这种实现方法布线简单,电路集成度高,体积小,功耗低,可靠性好,是最佳实现方案。文中就是用这种方案实现了该探测器的奇偶校正电路。  相似文献   
995.
M.  C.  E.  D.  B.  S.  A. 《Sensors and actuators. A, Physical》2004,110(1-3):385-389
We have investigated the static and dynamic behavior of piezoelectric (PZT) actuated SiO2/Si membranes with an off-centered PZT patch. Three-dimensional wide-field interferometer has been used to achieve measurement of membrane topography and bending. It is demonstrated that the piezoelectric coefficient d31 can be extracted directly from these three-dimensional static deformation measurements. We have also shown that polarization voltage of an off-centered PZT patch influences in a different manner the resonant frequency shift of the first and the second vibration modes. Degenerated modes can be also discriminated thanks to the positioning of the PZT patch.  相似文献   
996.
In an anthropometric measurement process, there are many factors which are error sources even if the observers are highly trained. Systematic or bias errors are possible and they are not clearly noticeable. In this work we propose two simple and adimensional indices to use in the quality control of anthropometric surveys.

Such indices are applicable only to a few anthropometric variables but the results found by this control can be an indication of the quality of the complete measurement process. The indices are defined as

and ses index is the same when the measures are obtained in sitting position. The observer must take those measurements again when the index values are higher than a selected threshold value before approving or rejecting the measure.

Relevance to industry

Anthropometric data are used in a wide variety of consumer products and in processes of industrial design. Wrong precision of data could cause problems in the industrial products. Those indices are useful to improve the accuracy and quality control of data.  相似文献   

997.
The activity of an insurance company with a reinsurance condition system is modeled on an infinite time interval. Payment times and sums insured are random. The amount of money replenished is selected as a control parameter. The task is to minimize the average insurance payment per unit time, thus optimizing investments.Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 172–176, November– December 2004.This revised version was published online in April 2005 with a corrected cover date.  相似文献   
998.
In this paper we investigate the use of the multi-layer perceptron (MLP) for system modelling. A new sigmoidal activation function is introduced and the study is focused at the utilization of this function on a MLP that performs modelling of dynamic, discrete time systems. The role of the activation function in the training process is investigated analytically, and it is proven that the shape of the activation function and it's derivative can affect the training outcome. The method is simulated at a well known benchmark, namely the three tank system, and is incorporated in a Fault Detection and Identification (FDI) method, also applied and simulated at the three tank system. Finally, a comparison is made with an approach that utilizes local model neural networks for system modeling.  相似文献   
999.
We introduce a general and in a certain sense time-optimal way of solving one problem after another, efficiently searching the space of programs that compute solution candidates, including those programs that organize and manage and adapt and reuse earlier acquired knowledge. The Optimal Ordered Problem Solver (OOPS) draws inspiration from Levin's Universal Search designed for single problems and universal Turing machines. It spends part of the total search time for a new problem on testing programs that exploit previous solution-computing programs in computable ways. If the new problem can be solved faster by copy-editing/invoking previous code than by solving the new problem from scratch, then OOPS will find this out. If not, then at least the previous solutions will not cause much harm. We introduce an efficient, recursive, backtracking-based way of implementing OOPS on realistic computers with limited storage. Experiments illustrate how OOPS can greatly profit from metalearning or metasearching, that is, searching for faster search procedures.  相似文献   
1000.
In this paper, a robust stable fuzzy control design based on feedback linearization is presented. Takagi–Sugeno fuzzy model is used as representing the nonlinear plant model and uncertainty is assumed to be included in the model structure with known bounds. For this structured uncertainty, the closed system can be analyzed by applying the perturbation system stability analysis to the fuzzy feedback linearization systems and a sufficient condition is derived to guarantee the stability of the closed-loop system with bounded parameter uncertainties. Based on the developed analysis method, we can design a robust fuzzy controller by choosing the control parameters satisfying the robust stability condition.  相似文献   
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