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991.
惠斯登电桥测电阻的误差分析 总被引:2,自引:0,他引:2
本文较系统地分析了用惠斯登电桥测电阻实验中的系统误差,并提出了代换法消除系统误差的方法. 相似文献
992.
P.A.M. Dos Santos 《Optics & Laser Technology》1992,24(3)
In this note attention is given to the holographic characterization of photorefractive sensitivity by the spatial light modulation dependence in a Bi12TiO20 crystal. A sample in the diffusion-only Bragg regime was used. The experiment improves the anisotropic self-diffraction properties of the material. Through this method, it is possible to find the best conditions for the fast response of the material when used as an optical holographic processor. 相似文献
993.
通过实验验证马吕斯定律,并分别在消光位置和最大光强位置作检测点,测量介质的费尔德常数.根据实验结果的分析,讨论实验中普遍存在的"在光强极大值和光强最大相对变化率位置"检测灵敏度的问题,得出在消光位置测量线偏振光旋转角最精确的结论. 相似文献
994.
M. Eslami 《Journal of Optimization Theory and Applications》1993,77(3):591-612
In this article, we present an algorithm leading to an optimal controller gain for the automatic regulation of a linear system (closed-loop policy) and to an optimal auxiliary input. This is used for the purpose of either system identification, resulting in the maximum sensitivity measure and thus increased accuracy (Refs. 1–25), or system sensitivity reduction, resulting in the minimum sensitivity measure and thus reliable operation (Refs. 26–46). These results, which are robust in terms of parameter variations, are developed without constraints on the input functions. 相似文献
995.
Marvin D. Troutt 《Mathematical Programming》1986,36(3):353-361
This paper studies a class of perturbations of a game matrix that alters each row by a different amount. We find that completely
mixed optimal strategies are stable under these perturbations provided the norm of the vector of additive amounts is sufficiently
small. Using this concept we give a new characterization of completely mixed grames. We also obtain a sensitivity result for
a class of perturbations of the technological coefficient matrix of positive linear programs. The stability of an optimal
strategy holds throughout at least a spherical neighborhood of the zero perturbation. We give a computational formula and
equivalent programming formulations for the radius of this neighborhood. 相似文献
996.
设M={A=⊕_(g∈G)A_g,V=⊕_(g∈G)V_g,W=⊕_(g∈G)W_g,B=⊕_(g∈G)B_g}与(,),[,]是一个G-分次Morita Context,且满足(V,W)=A,[W,V]=B,A,B都有单位元.本文证明τG(B):[W,ΥG(A)V]=【WΥc(A),V],ΥG(A)=(V,ΥG(B)W)=(VΥG(B),W)其中ΥG代表P_G(分次素根),J_G(分次Jacobson根),K_G(分次Koethe根),L_G(分次Levitzki根)和s_G(分次强素根),us_G(分次一致强素根). 相似文献
997.
二层决策问题的灵敏度分析(2) 总被引:1,自引:0,他引:1
二层决策系统包含着两个最优化决策问题,其中上层决策问题的目标值是由下层决策的解所隐含地确定的.本文研究了二层决策问题的另一方面的灵敏度分析问题,讨论了上层决策者的价值系数发生变化而二层决策问题的最优解不变所产生的灵敏度分析问题.为了确定二层决策问题价值系数发生变化的范围,首先我们给出了灵敏度分析的基本方法,结合“k th-best”算法我们又给出了灵敏度分析的操作步骤.在所确定的变化范围内,价值系数的变化,不会引起二层决策问题的全局最优解的变化,从而为决策者提供了相对稳定的决策方案.最后我们给出了数值实例,它表明本文所给出的灵敏度分析的方法是正确的. 相似文献
998.
B.H. Suits A.N. Garroway J.B. Miller 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1998,135(2):373-379
The use of surface coils in magnetic resonance is widespread. Examples include MRI, detection of subsurface aquifers by NMR, and, more recently, landmine detection by nuclear quadrupole resonance. In many of these cases a finite-sized sample to be examined is contained within a larger medium that is a poor electrical conductor, and eddy currents induced by the RF fields provide a loss mechanism that reduces the effective quality factorQof the transmitter and receiver coils. Here the losses induced in a circular surface coil (a horizontal loop antenna) separated a distance from a dissipative medium are calculated and compared to measurements. It is shown that often the overall efficiency of the coil for magnetic resonance can be improved by displacing the coil away from the conducting medium a prescribed “lift-off” distance. The use of a gradiometer as a surface coil is also examined, and it is shown by theory and experiment that in certain circumstances such a gradiometer can be more efficient than a conventional surface coil for inspection of conducting media. 相似文献
999.
原理分析和实验结果证明了:通过一种含有空腔的金属电极与压电复合材料的界面作用,发迹了应力的作用式,提高了d33值;并使数值符号相反的d33和d31均对dh值起加大作用。 相似文献
1000.
A survey of various aspects of the theory and application of degeneracy graphs (DGs for short) is given. The notion and some basic properties of DGs are introduced, cycling of the simplex method is discussed, the neighborhood problem is tackled, and the application of the so-called optimum DGs to particular problems which are connected with optimal degenerate solutions of a linear programming problem is presented. The impact of weakly redundant constraints on various postoptimal analyses under degeneracy is briefly described. 相似文献