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141.
Ivo Klik 《Journal of statistical physics》1991,62(1-2):389-397
The influence of the Bardeen-Herring back-jump correlations on the Fermi-Dirac statistics of the one-dimensional nonhomogeneous fermionic lattice gas is studied by the Monte Carlo simulation technique and semianalytically. The resulting distribution is obtained, exhibiting increased population of the lower levels in comparison to the Fermi-Dirac statistics. 相似文献
142.
Convexlike and concavelike conditions in alternative,minimax, and minimization theorems 总被引:7,自引:0,他引:7
S. Paeck 《Journal of Optimization Theory and Applications》1992,74(2):317-332
Convexlike and concavelike conditions are of interest for extensions of the Von Neumann minimax theorem. Since the beginning of the 80's, these conditions also play a certain role in deriving generalized alternative theorems of the Gordan, Motzkin, and Farkas type and Lagrange multiplier results for constrained minimization problems.In this paper, we study various known convexlike conditions for vector-valued functions on a set and investigate convexlike and concavelike conditions for real-valued functions on a product setC×D, where we are mainly interested in the relationships between these conditions. At the end of the paper, we point out several conclusions from our results for the above-mentioned mathematical fields.The author is indebted to Dr. R. Reemtsen and Dr. V. Jeyakumar for their helpful comments during the preparations of this paper. 相似文献
143.
This paper is concerned with optimal control problems of Mayer and Bolza type for systems governed by a semilinear state equationx(t)=Ax(t) + f(t, x(t), u(t)), u(t) U, whereA is the infinitesimal generator of a strongly continuous semigroup in a Banach spaceX. We prove necessary and sufficient conditions for optimality and then use these conditions to investigate properties of the value function related to superdifferentials. Conversely, we use the value function to obtain criteria for optimality and feedback systems.Work (partially) supported by the Research Project Equazioni di evoluzione e applicazioni fisicomatematiche (M.U.R.S.T.-Italy). 相似文献
144.
A. Linnemann 《Journal of Optimization Theory and Applications》1982,38(4):483-511
In this paper, we present a unified theory of first-order and higher-order necessary optimality conditions for abstract vector optimization problems in normed linear spaces. We prove general multiplier rules, from which nearly all known first-order, second-order, and higher-order necessary conditions can be derived. In the last section, we prove higher-order necessary conditions for semi-infinite programming problems.This work was developed within the Forschungsschwerpunkt Dynamische Systeme, Universität Bremen, Bremen, West Germany.The author wishes to thank Prof. Dr. D. Hinrichsen for his helpful remarks and discussions during the preparation of this work. 相似文献
145.
G. Gopalakrishnan Nair 《Journal of Optimization Theory and Applications》1979,28(3):429-434
The convergence of the Luus-Jaakola search method for unconstrained optimization problems is established.Notation
E
n
Euclideann-space
- f
Gradient off(x)
- 2
f
Hessian matrix
- (·)
T
Transpose of (·)
-
I
Index set {1, 2, ...,n}
- [x
i1
*(j)
]
Point around which search is made in the (j + 1)th iteration, i.e., [x
1l
*(j)
,x
2l
*(j)
,...,x
n1
*(j)
]
-
r
i
(i)
Range ofx
il
*(i)
in the (j + 1)th iteration
-
l
1
mini {r
i
(0)
}
-
l
2
mini {r
i
(0)
}
-
A
j
Region of search in thejth iteration, i.e., {x E
n:x
il
*(j-1)
–0.5r
i
(j-1)
x
ix
il
*(j-1)
+0.5r
i
(j-1)
,i I}
-
S
j
Closed sphere with center origin and radius
j
-
Reduction factor in each iteration
-
1–
- (·)
Gamma function
Many discussions with Dr. S. N. Iyer, Professor of Electrical Engineering, College of Engineering, Trivandrum, India, are gratefully acknowledged. The author has great pleasure to thank Dr. K. Surendran, Professor, Department of Electrical Engineering, P.S.G. College of Technology, Coimbatore, India, for suggesting this work. 相似文献
146.
147.
综述了负载或非负载的金属氧化物催化剂体系上,富氧条件下NO的非选择性催化还原反应性能及反应机理.着重讨论了还原剂种类、催化剂结构与化学性质对催化反应的影响及催化剂的耐水性和耐SO2性能.探讨并总结了金属氧化物催化剂体系上NO的还原机理. 相似文献
148.
周志昂 《西南师范大学学报(自然科学版)》2005,30(2):221-225
在序线性拓扑空间中定义了广义凸集值映射.引进了相对内部.应用凸集分离定理建立了一个广义凸集值映射的择一性定理.运用此定理获得了弱有效解意义下的集值向量优化问题的最优性条件. 相似文献
149.
根据种群生物量增长模式,提出一种新的种群增长的数学模型.该模型改进了Logistic模型,可以用来描述种群数量随时间和环境条件变化的增长规律,具有更广泛的代表性和适用性.在新的模型中,Logistic模型仅为它的一个特例. 相似文献
150.
生态存在是生态哲学的一个基本范畴,它有自己独特的涵义、特点和构成要素,生态存在和生态意识的关系问题是生态哲学的基本问题。学术界存在着脱离生态存在而单纯研究生态意识的倾向,必须加以批判。不是人们的生态意识决定人们的生态存在,相反地.是人们的生态存在决定人们的生态意识,生态意识是生态存在的反映。 相似文献