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991.
The refractive medium is used in moire interferometry and holographic grating fabrication technique. The sensitivity of traditional
interferometry and the frequency of grating are enhanced effectively. These two novel techniques extend the application scope
of the moire interferometry and facilitate the realization of superlattice method in micromechanics study.
The project supported by the National Natural Science Foundation of China 相似文献
992.
L. M. Meaux 《Mathematical and Computer Modelling》2002,35(13):1483-1488
Potter and Anderson [1] have developed a Bayesian decision procedure requiring the specification of a class of prior distributions restricted to have a minimal probability content for a given subset of the parameter space. They do not, however, provide a method for the selection of that subset. We show how a generalization of Gauss' inequality can be used to determine the relevant parameter subset. 相似文献
993.
微机械生化传感器 总被引:1,自引:0,他引:1
自从Clark和Lyons在1962年研制出第一个生物传感器以来,探测各种生物和化学分子的生化传感器相继问世。这类传感器的基本原理是通过生化敏感层,被分析分子在敏感层上的物理或化学吸附被换能器转化为电信号。在众多的设计中,将活泼的生化敏感材料涂镀在硅器件表面是一个最有新意的设想。以往的硅生化传感器多设计为膜片式,器件的灵敏度受到限制。硅微机械悬臂梁是一种灵敏度极高的器件,近年来在传感器领域受到关注。文章总结了目前世界上硅基微悬梁生化传感器的最新发展动态。对几种硅悬臂梁的设计方法和工作原理进行了讨论,并给出了几种新型微生化气体和液体传感器检测不同有机分子和生物分子的结果。 相似文献
994.
最优值函数的方向导数 总被引:2,自引:0,他引:2
本文详细介绍了参数非线性规划问题最优值函数的方向导数的存在性、表示形式和有关的发展历史,本文不仅讨论了这一问题的经典结论,还叙述了最近二十年来的新结果。本文最后指出进一步研究的方向。 相似文献
995.
Distribution sensitivity for certain classes of chance-constrained models with application to power dispatch 总被引:1,自引:0,他引:1
Using results from parametric optimization, we derive for chance-constrained stochastic programs quantitative stability properties for locally optimal values and sets of local minimizers when the underlying probability distribution is subjected to perturbations in a metric space of probability measures. Emphasis is placed on verifiable sufficient conditions for the constraint-set mapping to fulfill a Lipschitz property which is essential for the stability results. Both convex and nonconvex problems are investigated. For a chance-constrained model of power dispatch, where the power demand enters as a random vector with incompletely known probability distribution, we discuss consequences of our general results for the stability of optimal generation costs and optimal generation policies.The authors thank P. Kleinmann (formerly with the Humboldt-Universität, Berlin, Germany) for his active cooperation in designing the power dispatch model and J. Mayer (MTA SZTAKI, Budapest, Hungary) for his insight into energy optimization. Further thanks are due to the referees for their constructive criticism.This research was developed in the course of a contract study between the International Institute for Applied Systems Analysis, Laxenburg, Austria and the Humboldt-Universität, Berlin, Germany. 相似文献
996.
We consider functions of maximum type (max functions for short), subject to (in)equality constraints. The space dimension is finite, and the maximum is taken over a compact manifold with boundary. Effective local minimization algorithms based on Newton's method can be derived in the case where a local minimum is nondegenerate (in a two-level sense). In fact, nondegeneracy refers on the one hand to a local (implicit) reduction of the original max function to another one, where the maximum is taken over a finite set. On the other hand, it refers to strict complementarity and nondegeneracy of the underlying quadratic form with respect to the reduced stationary situation. As the main goal, we show that the set ofn-parameter families of functions, for which the stationary points of the corresponding max function are nondegenerate, constitutes an open and dense subset in the space of alln-parameter families (the topology used takes derivatives up to second order into account). An application to approximation problems of Chebyshev type is presented. 相似文献
997.
K. Malanowski 《Journal of Optimization Theory and Applications》1987,53(3):429-449
A family of optimal control problems for discrete systems that depend on a real parameter is considered. The problems are strongly convex and subject to state and control constraints. Some regularity conditions are imposed on the constraints.The control problems are reformulated as mathematical programming problems. It is shown that both the primal and dual optimal variables for these problems are right-differentiable functions of a parameter. The right-derivatives are characterized as solutions to auxiliary quadratic control problems. Conditions of continuous differentiability are discussed, and some estimates of the rate of convergence of the difference quotients to the respective derivatives are given. 相似文献
998.
Study of initiation reactivity of some plastic explosives by vacuum stability test and non-isothermal differential thermal analysis 总被引:5,自引:0,他引:5
On the basis of measurements of 18 high explosives by means of the Czech Vacuum Stability Test (VST) STABIL, a relationship has been specified between the results of this test and those of Russian manometric method. The said relationship was used to predict the Arrhenius parameters (Ea and log A values) of four plastic explosives based on RDX and one high explosive based on PETN (Semtex). The slopes EaR−1 of Kissinger's equation were specified by means of non-isothermal differential thermal analysis (DTA) and evaluation of the measurement results by means of the Kissinger method. The role played by binders and plasticizers in thermal decomposition of nitramines was pointed out on the basis of relationship between the Ea values obtained from VST and the EaR−1 values obtained from DTA, both for plastic explosives, eight nitramines, Composition B and PETN. The relationships between the EaR−1 values and thermostability threshold was specified for the given group of explosives. The relationship classify some of the studied plastic explosives as belonging to nitramines with steric hindrance in the molecule (CPX, TNAZ and HNIW). The relationship between EaR−1 values and drop energies, Edr, sharply differentiates between plastic explosives and individual nitramines. From the relationship between the Edr and D2 values it was found that the increasing performance of the studied nitramines and plastic explosives is connected with the decrease in their impact sensitivity. Also specified are the approximate linear dependences between the peak temperatures of exothermic decomposition of all the explosives studied and their ignition temperatures, Tig, or critical temperatures, Tc; these dependences were applied to prediction of Tig and Tc of both the studied plastic explosives and some of the nitramines. 相似文献
999.
Hermann Glaeser 《Accreditation and quality assurance》2004,9(4-5):205-208
Foodstuffs shall not contain pathogenic micro-organisms in concentrations which may cause a risk for consumer health. The relevant legislation therefore normally contains the requirement that these organisms are absent in a certain product quantity (e.g. 25 g). It is not at all easy to prove the absence. Reference materials are important tools for checking the performance of qualitative methods. These materials should contain the target organism in low numbers (close to 1 cell/capsule). Furthermore, the most important interfering micro-organisms should be taken into consideration, when testing the performance of detection methods using reference materials. When developing reference materials with the described characteristics, detection methods are needed which give a positive result with one or a few cell(s) of the target organism. While these requirements appear to be fairly obvious, precise statements on method performance are rarely available. Strategies to obtain this information are discussed. Further important aspects are practical considerations when using such reference materials for method evaluation. Statistical procedures can help to obtain the relevant information with a minimum of effort.Presented at BERM-9—Ninth International Symposium on Biological and Environmental Reference Materials, June 15–19, 2003, Berlin, Germany. Views expressed in this paper represent the personal opinion of the author. 相似文献
1000.
温度及pH敏感N-异丙基丙烯酰胺/β-环糊精水凝胶的合成与性能研究 总被引:9,自引:0,他引:9
用顺丁烯二酸酐 (MAH)对具有分子包结能力的 β 环糊精 (β CD)进行化学改性 ,合成出了丁烯二酸单酯化 β CD单体 (MAH β CD) .通过氧化还原自由基引发MAH β CD与N 异丙基丙烯酰胺 (NIPA)聚合 ,合成出含 β CD结构单元的新型水凝胶 .用核磁共振、红外光谱及元素分析对MAH β CD单体及共聚物的结构和组成进行了表征 .溶胀研究结果表明 ,该水凝胶具有较好的pH、温度及离子强度敏感性 ;并且水凝胶在较高羧基(—COOH)含量和弱碱环境中 ,仍能表现出明显的温敏性 相似文献