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121.
无限维空间中强拟凸向量优化问题有效解集的连通性   总被引:3,自引:0,他引:3  
本文在无穷维空间引进增强凸变换的概念,在约束集是紧和凸的条件下目标函数是连续和强拟凸的,我们得取到向量极小问题有效解集的连通性。  相似文献   
122.
Absorption coefficient measurements of strongly scattering and weakly absorbing media have been performed using time resolved transmittance of a 100 fs pulse through a 30 mm slab containing latex spheres suspended in water and absorbing ink solutions. The scattering and absorption coefficients were selected so that the optical properties of the media were similar to those of biological tissues. Measured curves of time-resolved transmittance of the pulse through the media were used to estimate the optical properties of the media. The experiment was made at two different wavelengths, 784 nm and 810 nm. Estimated absorption coefficients were in good agreement with those measured in a nonscattering case by a spectrophotometer.Presented at the 7th International Workshop on Multiple Scattering Lidar/Light Experiments (MUSCLE7), July 21-23 1994, Chiba, Japan.  相似文献   
123.
The presence of the σ-phase in Fe-Cr alloys (eg. Stainless steel) is important in industrial applications and from an academic point of view. The presence of the σ-phase in these alloys drastically affects their mechanical properties and their resistance to various corrosive media. In the present investigation Fe-Cr alloys containing different amounts of Mo were prepared and the transformation to the σ-phase was carried out by isothermally annealing the samples for various periods in an argon atmosphere. It will be shown that the presence of Mo has a dramatic accelerating effect on the rate of the σ-phase formation in these alloys. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
124.
探讨了n维复形上一类具有混合约束的多目标规划问题,并运用代数拓扑方法得出这类规划问题的有效解。  相似文献   
125.
We establish necessary and sufficient conditions for properly efficient solutions of a class of nonsmooth nonconvex optimal control problems with multiple fractional objective functions, linear dynamics, and nonlinear inequality constraints on both the state and control variables. Subsequently, we utilize these proper efficiency criteria to construct two multiobjective dual problems and prove appropriate duality theorems. Also, we specialize and discuss these results for a particular case of our principal problem which contains square roots of positivesemidefinite quadratic forms. As special cases of the main proper efficiency and duality results, this paper also contains similar results for control problems with multiple, fractional, and ordinary objective functions.  相似文献   
126.
超高灵敏显色反应的理论和实践   总被引:3,自引:0,他引:3  
本文系统评述了我国在ε≥1*10^6L.mol^-1.cm^-1的超高灵敏显色反应的理论和实践,总结了规律和发展趋势。文献127篇。  相似文献   
127.
The properness of the efficient solution of the optimal problem with multicriteria has been independently defined by Kuhn and Tucker, Geoffrion, and Klinger. A theorem of Geoffrion describes the relation between Geoffrion's and Kuhn and Tucker's properness. In this paper, the dual part of the theorem is given, and some geometric approach is applied to derive the optimal conditions of proper efficient solutions and improper efficient solutions.  相似文献   
128.
王晓方  沈百飞 《光学学报》1994,14(8):15-818
本文提出一种在激光等离子体中产生高丰度高电荷态离子的新途径,即通过共振光激发和碰撞电离混合过程来实现,模型计算表明,这一混合过程对提高高电荷态离子丰度的有效性,有关实验也证明这一过程的重要作用。  相似文献   
129.
We have carried out experiments of two-photon excitation of vapor phase H2O and D2O molecules at atmospheric pressure. A narrow-band tunable UV OPO laser is used in the experiments. Transient B 1 B 1 emission from the excited predissociating state is seen in both cases. The complete B 1 A 1 fluorescence excitation spectrum in the spectral range of 245-250 nm is measured and compared with theory. It is shown that the predissociation rate increases with the rotational quantum number K' a > 2 more strongly than with K ′2 a . No perturbation effects on the measured LIF spectra are observed at a laser power density below 2 GW/cm2. Experimental results indicate a negligible contribution from both molecular association and collisions with atmospheric gases. Only an extremely weak vibrational progression belonging to the second positive system of N2 has been observed, which appears to be due to energy and charge transfer in N + 2 * + H 2 O collisions. Received 25 January 2002 / Received in final form 27 May 2002 Published online 4 March 2003  相似文献   
130.
On the existence of efficient points in locally convex spaces   总被引:1,自引:0,他引:1  
We study the existence of efficient points in a locally convex space ordered by a convex cone. New conditions are imposed on the ordering cone such that for a set which is closed and bounded in the usual sense or with respect to the cone, the set of efficient points is nonempty and the domination property holds.  相似文献   
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