Dynamique motivationnelle de l'epuisement et du bien-etre chez des enseignants africains.

This study examines the links between antecedents and consequences of Gabonese teachers' (N= 152) work motivation. The theoretical underpinnings are based on the Motivational Model of Job Burnout (MMJB) which is grounded in Self-Determination Theory (SDT) and states that the more supervisors satisfy an employee's need for self-determination, competence, and relatedness, the more self-determined is the latter's work motivation. The level of self-determined motivation has an impact on job satisfaction, which in turn determines life satisfaction. Higher levels of self-determined motivation also buffer emotional exhaustion and psychological distress. The model was confirmed via structural equation modeling and provides support for the validity and generalizability of the MMJB and SDT. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Many-Body Terms in van der Waals Cohesion Energy of Nanotubes

We have developed a model for the calculation of van der Waals force for layered systems with axial symmetry. Our result can be applied to compute the cohesion of a carbon nanotube to a substrate, the cohesion between nanotubes, and between shells of multiwall nanotubes. We have obtained unusal power laws for the distance dependence of the many-body van der Waals potential.     

Web-based systems design: a study of contemporary practices and an explanatory framework based on “method-in-action”

This paper reports the findings of a detailed study of Web-based systems design (WBSD) practices in Ireland based on data collected over a 3-year period (2002–2005), the objectives of which were to (1) contribute towards a richer understanding of the current “real-world” context of WBSD by characterising the profile of a typical project (team size, timeframe, nature of requirements, etc.) and identifying the key challenges, constraints, and imperatives (i.e. “mediating factors”) faced by Web-based system designers, and (2) understand how those contextual parameters and mediating factors influence the activity of WBSD as regards the selection and enactment of whatever design practices are therefore engaged (i.e. the use of methods, procedures, etc.). Data was gathered through a survey which yielded 165 usable responses, and later through a series of semi-structured qualitative interviews. Using grounded theory, an explanatory conceptual framework is derived, based on an extension of the “method-in-action” model, the application of which to WBSD has not been previously investigated in depth. It is proposed that this framework of WBSD issues is valuable in a number of ways to educators, researchers, practitioners, and method engineers.     

Multiagent learning using a variable learning rate

Learning to act in a multiagent environment is a difficult problem since the normal definition of an optimal policy no longer applies. The optimal policy at any moment depends on the policies of the other agents. This creates a situation of learning a moving target. Previous learning algorithms have one of two shortcomings depending on their approach. They either converge to a policy that may not be optimal against the specific opponents' policies, or they may not converge at all. In this article we examine this learning problem in the framework of stochastic games. We look at a number of previous learning algorithms showing how they fail at one of the above criteria. We then contribute a new reinforcement learning technique using a variable learning rate to overcome these shortcomings. Specifically, we introduce the WoLF principle, “Win or Learn Fast”, for varying the learning rate. We examine this technique theoretically, proving convergence in self-play on a restricted class of iterated matrix games. We also present empirical results on a variety of more general stochastic games, in situations of self-play and otherwise, demonstrating the wide applicability of this method.     

Have it your way and mine: The theory of styles

Olsen is right to note what can be done with a good theory and the right machine. His particular theory, however, is not transferable to literary studies. If we need a new model, I would suggest that cognitive science can provide a few interesting ones. I have begun to do some work based on David Marr's VISION, in which he hypothesizes two levels of processing within the visual module. My speculation has been on the parallel existence of distinguishable levels of conceptual or language organization which would correspond to the viewer and object centered perspectives Marr describes for vision. I propose to explore the possibility that we may find here the model for the existence of stylistic individualism within overarching historical stylistic generalizations, and even more, that this may be what feminists are searching for when they try to resist being coopted by the masculine language of objectivity. Ellen Spolsky teaches English literature and literary theory and is the Director of the Lechter Institute for Literary Research at Bar-Ilan University, Israel. Her latest book is Gaps in Nature: Literary Interpretation and the Modular Mind(SUNY Press, 1993).     

WAVELET ALGORITHM FOR INTEGRAL OPERATOR EQUATION AND ITS APPLICATIONS TO ELECTROMAGNETIC PROBLEMS

A brief summary of the basic theory of wavelet is proposed. The properties of wavelet function are discussed. The possible applications of wavelet to electromagnetics are given. Examples show that the wavelet method is feasible and effective for solving electromagnetic problems.     

新型蓝绿发光材料ZnSe／BeTe超晶格的能带剪裁

由于器件的快速退化，101.5小时似乎成了Znse基蓝绿色半导体激光器难于逾越的寿命极限。分析退化机制，发现在强电流注入的半导体激光器中，热退化具有重要影响。研究表明，用作载流子限制层的宽带Ⅱ-Ⅵ族四元合金（如ZnMgSSe）只能对ZnSe中的电子有效地限制，无法对空穴很好地限制;而对BeTe，却只能对空穴进行有效的限制，无法对电子很好地限制。这导致ZnSe（或BeTe）活性层空穴（或电子）漏电发热，引起退化。本文提出以ZnSe／BeTe超晶格为蓝绿发光层，并用包络函数理论具体计算了阱宽、垒宽对载流子能级的不同影响，考察了ZnSe、BeTe厚度比和超晶格周期对带隙、载流子限制能力的调节。为研制新型长寿命蓝绿色半导体激光器提供了一条新的途径。     

The factor-analytic approach to intelligence is alive and well: A review of Carroll, J. B. (1993). Human cognitive abilities: A survey of factor-analytic studies.

Reviews the book, Human cognitive abilities: A survey of factor-analytic studies by J. B. Carroll (see record 1993-97611-000). Carroll divides his book into three parts. The first is a historical and conceptual review of psychometric theory. Carroll begins by clearly defining and differentiating key concepts such as ability, aptitude, achievement, latent trait, and intervening variable, although recognizing that in practice it is often difficult to make absolute distinctions. The second part, and the bulk of the book, is a detailed analysis and synthesis of a myriad of findings in the area of cognitive abilities. In the third part of his book, Carroll summarizes his undertaking and addresses traditional concerns and controversies. He compares and contrasts his model of cognitive abilities with that of others. Although Carroll's book does not and indeed cannot resolve the issues and controversies concerning the nature of human cognitive abilities, it does represent a notable contribution to our ongoing endeavours. It undoubtedly is a book that anyone interested in cognitive abilities would wish to explore because of its encyclopedic, in-depth coverage of the topic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

超高压输电线路分裂导线通道模式理论分析

本对分裂导线传输电磁波的模式理论进行了分析，从所解特征根中选择一组最简单的模分量传递信息，并阐述了传输规律。     

采样定理的内在不自洽性和工程应用的局限性——采样定理和奈奎斯特准则研究·上篇

推导证明了作为通信理论基石之一的采样定理及其公式存在着两个矛盾：内在不自洽性，即采样定理与其公式的推导前提条件相矛盾；采样定理在工程实际应用时的严重局限性