Response covariance-based sensor placement for structural damage detection

One important function of a structural health monitoring system is to detect structural damage in a structure. However, this is a very challenging task since the measurement is often incomplete in a civil structure due to a limited number of sensors. This paper presents a response covariance-based sensor placement method for structural damage detection with two objective functions for optimisation. The relationship between the covariance of acceleration responses and the covariance of unit impulse responses of a structure subjected to multiple white noise excitations is first derived. The response covariance-based damage detection method is then presented. Two objective functions based on the response covariance sensitivity and the response independence are, respectively, formulated and finally integrated into a single objective function for optimal sensor placement. Numerical studies are conducted to investigate the feasibility and effectiveness of the proposed method via a three-dimensional frame structure. Numerical results show that the proposed method with the backward sequential sensor placement algorithm is effective for damage detection.     

嵌入式单地址空间操作系统动态加载的研究

目前某些非智能手机或嵌入式系统由于不是虚拟地址空间,无法动态加载应用程序和更新系统软件,如果更新需要重新编译链接整个系统软件,限制了嵌入式系统灵活性和扩展性,若能实现模块和应用程序的动态加载,可以提高系统的灵活性和扩展性。本文从理论上详细分析动态加载需要解决的问题,如动态模块的执行,地址无关的代码和系统接口的调用等问题,并给出了详细的参考实现,并在非智能手机平台上作了验证,可以实现设计的动态加载。本文最后对动态加载的系统安全和进一步的扩展做出了分析。     

An improved independent component regression modeling and quantitative calibration procedure

An improved independent component regression (M‐ICR) algorithm is proposed by constructing joint latent variable (LV) based regressors, and a quantitative statistical analysis procedure is designed using a bootstrap technique for model validation and performance evaluation. First, the drawbacks of the conventional regression modeling algorithms are analyzed. Then the proposed M‐ICR algorithm is formulated for regressor design. It constructs a dual‐objective optimization criterion function, simultaneously incorporating quality‐relevance and independence into the feature extraction procedure. This ties together the ideas of partial‐least squares (PLS), and independent component regression (ICR) under the same mathematical umbrella. By adjusting the controllable suboptimization objective weights, it adds insight into the different roles of quality‐relevant and independent characteristics in calibration modeling, and, thus, provides possibilities to combine the advantages of PLS and ICR. Furthermore, a quantitative statistical analysis procedure based on a bootstrapping technique is designed to identify the effects of LVs, determine a better model rank and overcome ill‐conditioning caused by model over‐parameterization. A confidence interval on quality prediction is also approximated. The performance of the proposed method is demonstrated using both numerical and real world data. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

机端(静态)励磁方式在发电厂中应用

本文通过对某热电厂全厂停电事故的描述和原因及改进措施的分析,探讨了发电机组机端静态励磁和无刷励磁的特点和应用场合,通过实例阐述了励磁方式的选择对电力系统稳定性的重要性。     

Mesh independence of galerkin approach by preconditioning

Preconditioning the discrete Galerkin system for a bounded elliptic linear problem, by the Choleski factors of the Gramian, we obtain a mesh independent condition number. Moreover, the rate of convergence of the multigrid method is also mesh independent. Our example give a justification to the oscillatory movement of the discrete solution of a well known problem.     

A test of independence based on a generalized correlation function

In this paper, we propose a novel test of independence based on the concept of correntropy. We explore correntropy from a statistical perspective and discuss its properties in the context of testing independence. We introduce the novel concept of parametric correntropy and design a test of independence based on it. We further discuss how the proposed test relaxes the assumption of Gaussianity. Finally, we discuss some computational issues related to the proposed method and compare it with state-of-the-art techniques.     

Business policy compliance in service-oriented systems

As business policies and environments change constantly, there is a need for service-oriented systems to be compliant, yet adaptive. The solution proposed in this paper is based on a clear architectural separation of policy specification, enforcement strategy and realization. Policy compliance is worked out as a rule transformation process mediating between the business policy language SBVR and Condition-Action (CA) rules. The solution supports adaptation caused by business policy evolution as well as adaptation caused by service evolution. In addition, the paper describes a novel truly service-oriented way of implementing compliance management and enforcement of business policies drawing on Adaptive Service Oriented Architecture (ASOA).     

SLD-博弈树中计算规则的独立性

本文提出SLD-博弈树的成功集的概念，证明对任何计算规则R，对应R产的SLD-博弈树的成功集相同，即SLD-博弈树的证明能力与计算规则无关，这就是计算规则的独立性．     

独立战争后美国高等教育慈善事业分析

发端于殖民地时期的美国高等教育慈善事业,独立战争后面临宗主国英国关闭捐赠之门以及各州开始逐渐介入高等教育事务等形势变化的挑战。与殖民地时期一样,此时期公益慈善事业仍然是美国高等教育的主要支撑者。虽然此时期开始有大笔捐赠出现,但小型捐赠和募集的方式仍然非常普遍。但与殖民地时期不同的是,此时期的美国高等教育慈善事业开始关注教育实验,并在新的形势下开辟新的高等教育慈善领域。     

A Behavioral Choice Model When Computational Ability Matters

This paper presents a model of how humans choose between mutually exclusive alternatives. The model is based on the observation that human decision makers are unable or unwilling to compute the overall worth of the offered alternatives. This approach models much human choice behavior as a process in which people seek to equate a less significant difference between alternatives on one dimension, thus leaving the greater one-dimensional difference to be differentiated as the determinant of the final choice. These aspects of the equate-to-differentiate model are shown to be able to provide an alternative and seemingly better account of the prominence effect. The model is also able to provide an explanation and prediction regarding the empirical violation of independence and transitivity axioms. It is suggested that the model allows understanding perplexing decision phenomena better than alternative models.