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1.
关于非线性多目标规划问题非劣解解法的探讨 总被引:4,自引:0,他引:4
非线性多目标规划是一类复杂的规划问题,由于其往往没有最优解,因此求其非劣解具有重要的意义。本首先探讨了无约束条件下非线性多目标规划的解法,然后提出了有约束条件下非线性多目标规划的一种解法。所述方法具有一定的普遍意义。 相似文献
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In this paper, we consider a minimax problem of optimal control for a class of strongly nonlinear uncertain evolution equations on a Banach space. We prove the existence of optimal controls. A nontrivial example of a class of systems governed by a nonlinear partial differential equation with uncertain spatial parameters is presented for illustration.This work was supported in part by the National Science and Engineering Research Council of Canada under Grant No. A7109 and The Engineering Faculty Development Fund, University of Ottawa.The authors would like to thank the anonymous reviewers for their valuable comments and suggestions. 相似文献
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J. Rana G.L. Goswami S.K. Jha P.K. Mishra B.V.S.S.S. Prasad 《Optics & Laser Technology》2007,39(2):385-393
An experimental investigation with 5 kW CW CO2 laser system was carried out to study the effects of different laser and process parameters on the microstructure and hardness of carbon steel specimen with varying carbon percentage. The laser beam is allowed to scan on the surface of the work piece varying the power (1.1–2.5 kW) and traverse speed (6–15 mm/s) at two different spot sizes using TEM01* mode laser beam. The most hardenable microstructure achieved in case of three grades of carbon steel and the most influencing parameter on the value of hardness are reported. Besides the above study, some multipass operations are also carried out to recommend an appropriate gap between consecutive passes. 相似文献
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To exploit the parallelism of optics in data processing,a suitable number system and an efficient encoding/decoding scheme for handling the data are very essential.In the field of optical computing and parallel information processing,several number systems like binary,quaternary,octal,hexadecimal,etc.have been used for different arithmetic and algebraic operations.Here,we have proposed an all-optical conversion scheme from its binary to its other 2n radix based form with the help of terahertz optical asymmetric demultiplexer (TOAD) based tree-net architecture. 相似文献
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Note on Generalized Quantum Gates and Quantum Operations 总被引:1,自引:0,他引:1
Yue-Qing Wang Hong-Ke Du Yan-Ni Dou 《International Journal of Theoretical Physics》2008,47(9):2268-2278
Recently, Gudder proved that the set of all generalized quantum gates coincides the set of all contractions in a finite-dimensional
Hilbert space (S. Gudder, Int. J. Theor. Phys. 47:268–279, 2008). In this note, we proved that the set of all generalized
quantum gates is a proper subset of the set of all contractions on an infinite dimensional separable Hilbert space ℋ. Meanwhile,
we proved that the quantum operation deduced by an isometry is an extreme point of the set of all quantum operations on ℋ.
This subject is supported by NSF of China (10571113). 相似文献
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Gauging operations can cause electrostatic ignition in road tankers during filling operations involving flammable liquids. For this reason, gauging from above the liquid surface should not be carried out in a road tanker containing a flammable atmosphere when hazardous conditions are present.Introduction of an overfilling sensor to automatically stop the filling in case of deviation can be a safety measure to prevent overfilling of the road tanker and the generation of a rather big flammable pool.Nevertheless, this situation generates a conflict of interest with the formerly described safety measure of preventing a charged liquid to approach a counter-electrode in presence of a explosive atmosphere.This situation has been assessed in detail by using a simulation program. It was clear that the gauge could lead to an ignition already when the liquid approached the edge of the gauge. A new design was defined to prevent such hazard. 相似文献
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HAN Lian-Fang CHEN Yue-Ming YUAN Hao 《理论物理通讯》2009,51(4):648-652
We propose a deterministic quantum secure direct two check photon sequences are used to check the securities of the communication protocol by using dense coding. The channels between the message sender and the receiver. The continuous variable operations instead of the usual discrete unitary operations are performed on the travel photons so that the security of the present protocol can be enhanced. Therefore some specific attacks such as denial-of-service attack, intercept-measure-resend attack and invisible photon attack can be prevented in ideal quantum channel. In addition, the scheme is still secure in noise channel. Furthurmore, this protocol has the advantage of high capacity and can be realized in the experiment. 相似文献