控制随机搜索法重力反演

在全局极小点的可能区间估计内进行完全搜索。通过多组估计值的平均来改善参数的估计。合理选择反演约束条件的准则是:要使要值在约束范围内,且范围不能无限宽;各变量的约束范围应尽可能同比例。     

平面机械系统运动学的分析方法

本文介绍一种机械系统运动学分析的通用方法。文中根据多刚体系统运动学的原理,建立了受约束机械系统的运动约束方程、速度方程及加速度方程,还详细推导了以铰接副及滑动副连接的两邻接刚体的雅可比矩阵和加速度方程右边项,以求进一步说明本方法。文后还给出了实例。     

三边交会简易平差法

本文论述从三个已知点向一个待定点用测边交会的方法确定其点位,并能估计其精度的简易平差法.     

PSICO: Solving Protein Structures with Constraint Programming and Optimization

In this paper we propose PSICO (Processing Structural Information with Constraint programming and Optimisation) as a constraint-based approach to determining protein structures compatible with distance constraints obtained from Nuclear Magnetic Resonance (NMR) data. We compare the performance of our proposed algorithm with DYANA (Dynamics algorithm for NMR applications) an existing commercial application based on simulated annealing. On a test case with experimental data on the dimeric protein Desulforedoxin, the method proposed here supplied similar results in less than 10 minutes compared to approximately 10 hours of computation time for DYANA. Although the quality of results can still be improved, this shows that CP technology can greatly reduce computation time, a major advantage because structural NMR technique generally demands multiple runs of structural computation.     

用VSP数据中下行P-SV转换横波求取横波速度

探讨了用零偏移距三分量VSP数据中的下行P－SV转换横波,求取厚度相当于VSP采集点距的地层横波速度。从井下检波器方位校正得到横向垂直分量,对其二维谱中各类波的能量和特点进行分析,通过二维滤波得到信噪比较高的下行转换横波,选取振幅较强的同相轴提取波至时间,获取了横波速率及泊松比。结果表明,即使是零偏移距VSP数据,只要其上有明显可见的转换横波,也能以采集点距的量级计算横波层速度。     

中原油田调整井钻井液配套技术

随着中原油田近几年定向调整井、加密井的增多。地层压力系统出现紊乱,地下已形成多套压力层系,加之注采井网密度过大．整个油田的压力系统处于难以掌握的混乱状态。钻井中因漏而塌、因塌而卡,由防漏导致出水,因压井而诱发井漏等复杂情况时有发生。针对濮城、文东区块的地质特点,制定了“调整井钻井液综合配套技术”．该技术包括防漏堵漏技术、防卡润滑技术、防塌技术、流变性控制及清砂工艺、防渗水措施等一系列配套技术。     

Mixed Dimensional Coupling in Finite Element Stress Analysis

Many analysis models utilize finite elements of reduced dimension. However, to capture stress concentrations at local details, it would be desirable to combine the reduced dimensional element types with higher dimensional elements in a single finite element model. It is therefore important in such cases to integrate into the analyses some scheme for coupling the element types that conforms to the governing equations of the problem. In this paper, a novel method that can correctly couple beams to solids, beams to shells and shells to solids for elastic problems is presented. The approach adopted is to equate the work done on either side of the interface between dimensions, and this leads to multi-point constraint equations, thus providing a relationship among nodal degrees of freedom between the differing element types. Example results show that the proposed technique does not introduce any spurious stresses at the dimensional interfaces. ID="A1" Correspondence and offprint requests to: C. G. Armstrong, School of Mechanical and Manufacturing Engineering, The Queen's University of Belfast, Ashby Building, Stranmillis Road, Belfast BT9 5AH, Northern Ireland. E-mail: c.armstrong@qub.ac.uk     

Multiconsistency and Robustness with Global Constraints

We propose a natural generalization of arc-consistency, which we call multiconsistency: a value v in the domain of a variable x is k-multiconsistent with respect to a constraint C if there are at least k solutions to C in which x is assigned the value v. We present algorithms that determine which variable-value pairs are k-multiconsistent with respect to several well known global constraints. In addition, we show that finding super solutions is sometimes strictly harder than finding arbitrary solutions for these constraints and suggest multiconsistency as an alternative way to search for robust solutions.Supported by the Danish Research Agency (grant # 272-05-0081).Basic Research in Computer Science, funded by the Danish National Research Foundation.     

县级电力调度命令票自动化生成系统研究

本文详尽地介绍了通过采用对电力调度命令票的科学分类的方法,有效解决县级调度命令票自动或辅助生成的计算机软件开发问题。     

Impact of racial perspectives and contextual variables on marital trust and adjustment for African American couples.

This study examined the associations of racial perspectives that represent pro-African American, anti-African American, or a mixture of these beliefs with marital trust and adjustment for African American couples (N=93). Religious well-being and socioeconomic status (SES) were examined as contextual moderators. For husbands only, the anti-African American perspective was inversely associated with couple functioning, the mixed perspective was inversely associated with marital trust, and the pro-African American perspective predicted marital trust only for husbands having relatively low religious well-being and relatively high SES. The limited effects of pro-African American attitudes suggest the need to evaluate a wider range of these attitudes in future research. Also, findings corroborate suggestions for therapists to routinely assess and address both cultural pride and shame issues relevant to African American couple relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)