一致凸性与不动点性质

本文引进(F~k)一致凸空间的概念,并借助于这一空间的框架形式,讨论了广义非扩张映象的不动点性质。本文的结果发展了最近Dulst[3],Jaggi[5],Kirk[6],Browder[2]中的主要结果。     

Some vector optimization problems in Banach spaces with generalized convexity

In this paper, we consider a vector optimization problem where all functions involved are defined on Banach spaces. New classes of generalized type-I functions are introduced for functions between Banach spaces. Based upon these generalized type-I functions, we obtain a few sufficient optimality conditions and prove some results on duality.     

关于滚子轴承外滚道度母线加工的讨论

文中着重分析比较了目前国内外关于滚子轴承外圈滚道母线的凸度加工的各种工艺方案,同时,探讨了其它技术方案的可行性,以便企业根据自身生产工艺状况,进一步实践探索。     

Sample Path Analysis for Continuous Tandem Production Lines

We consider a tandem production line where the product flowing through the line is continuous fluid. We call such a line a continuous tandem (CT) line. We derive a recursive representation for the departure time of products in CT lines. Next, we apply sample path analysis techniques to prove that the departure time is convex (in the sense of strong stochastic convexity) in the flow rates of the machines. We then prove that the infinitesimal perturbation analysis (IPA) estimate, for the gradient of throughput with respect to machine flow rates, is strongly consistent.     

Solvability conditions for variational-like inequalities

Solvability conditions are proposed for variational-like inequalities defined on bounded and unbounded feasible sets under the assumption of generalized (quasi-and 0-diagonal) convexity of the mappings used in the problem being solved. Existence and uniqueness conditions are proposed for its solution. Mappings of variational-like inequalities are assumed to be generally convex, strongly monotone, and Lipshitzian. Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 33–38, November–December 2008.     

Motion Balance Filtering

This paper presents a new technique called motion balance filtering, which corrects an unbalanced motion to a balanced one while preserving the original motion characteristics as much as possible. Differently from previous approaches that deal only with the balance of static posture, we solve the problem of balancing a dynamic motion. We achieve dynamic balance by analyzing and controlling the trajectory of the zero moment point (ZMP). Our algorithm consists of three steps. First, it analyzes the ZMP trajectory to find out the duration in which dynamic balance is violated. Dynamic imbalance is identified by the ZMP trajectory segments lying out of the supporting area. Next, the algorithm modifies the ZMP trajectory by projecting it into the supporting area. Finally, it generates the balanced motion that satisfies the new ZMP constraint. This process is formulated as a constrained optimization problem so that the new motion resembles the original motion as much as possible. Experiments prove that our motion balance filtering algorithm is a useful method to add physical realism to a kinematically edited motion.     

The convexity about ultimate bearing hypersurfaces of structures

The relationship between the convexity on the ultimate bearing surface of a structure and the secondorder effects of loads is discussed. All of generalized non-overload forces acted on a structure forms a convex set when ignoring the second-order effects (coupling effects between the generalized forces). It is true also when the Hessian matrix composed of the second-order partial derivatives on the hypersurface about the ultimate bearing of the structure is negative definite. The outward convexity is kept when the surface is expressed by certain dimensionless parameters. A series of properties based on the convexity are pointed out. Some applications in the analysis of bearing capacity of structures were illustrated with examples. The study shows that an evaluation about the bearing capacity state of a complex structure can be made on the basis of several points on the surface of the ultimate bearing of the structure.     

Quadratic function expressions and static structure characteristics in power systems

In this study we formulate the power equations of power systems that are operating in their steady states into what we call the dtic and Hermitian power equations in terms of nodal active/reactive powers. These quadratic and Hermitian power equations are then generalized in terms of active/reactive power indices, based on which we complete three tasks: (i) deriving possible eigenvalue/singular‐value inequalities for nodal voltage stability evaluation with or without power flow computations; (ii) examining possible positive/negative definiteness, semi‐definiteness and indefiniteness of power systems that are useful in nodal voltage stability evaluation and convex/concave analysis; and (iii) scrutinizing possible convexity/concavity properties of power systems and their application. The static structure characteristics of power systems are reported here for the first time and theoretical results related to these static structural characteristics are significant in evaluating nodal voltage stability of the power systems quantitatively and qualitatively. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

板形控制技术及应用

概述了板形控制原理.根据有载辊缝形状方程,分析了影响板形、板凸度的诸项因素,综合介绍了板形控制技术及发展趋势.