Regression analyses of counts and rates: Poisson, overdispersed Poisson, and negative binomial models.

The regression models appropriate for counted data have seen little use in psychology. This article describes problems that occur when ordinary linear regression is used to analyze count data and presents 3 alternative regression models. The simplest, the Poisson regression model, is likely to be misleading unless restrictive assumptions are met because individual counts are usually more variable ("overdispersed") than is implied by the model. This model can be modified in 2 ways to accommodate this problem. In the overdispersed model, a factor can be estimated that corrects the regression model's inferential statistics. In the second alternative, the negative binomial regression model, a random term reflecting unexplained between-subject differences is included in the regression model. The authors compare the advantages of these approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysing IOIS adoption through structural contradictions

Despite extensive research and practitioner literature on inter-organizational information systems (IOIS), our understanding of non-adoption still has some under-explored issues. This paper offers an explanation of non-adoption that focuses on the potential structural changes that IOIS adoption entails; in particular, we contend that the contradictions between the initial social structure and the structure enacted in the use of an IOIS can be a cause of non-adoption. This paper analyses adoption from a logic of opposition where non-adoption occurs because forces of transformation are offset by forces of persistence. Relying on the concepts of social structure, duality of structure, and structural contradiction from Structuration theory, we develop a framework that categorizes the underlying social structure where an IOIS is to be adopted, and formulate some theoretical propositions. From a practitioner perspective, this paper contends that the fact that IOIS management uncovers the contradictions in the social structure that result from IOIS adoption can help avoid dead ends. Accordingly, this framework, which can be used as a coarse-grained picture for anticipating adoption problems, can inform managers when devising an IOIS implementation strategy.     

Estimation of Basins of Attraction for Uncertain Systems with Affine and Lipschitz Dynamics

This paper is devoted to estimation and numerical approximation of basins of attraction for a class of uncertain systems. We consider systems described by a differential equation depending of a disturbance known by its bounds. By using viability theory tools, we derive basins of attraction lower and upper estimates. We present numerical simulation results of the viability kernel algorithm to basin of attraction approximation problems.     

Formal aspects of computing: LATEX style guide for authors

This guide is for authors who are preparing papers forFormal Aspects of Computing using the \(LaT_E X\) document preparation system and the FAC style file.     

Uncovering a User’s Hidden Tracks

Uncovering a computer user’s past activities is one of the most common tasks for a computer forensics investigator. Often, this task is straightforward and can be accomplished primarily through a detailed analysis of the relevant data and application files present on a system. However, a tremendous amount of information can also be discovered which might otherwise be thought lost or hidden. By discovering data on a computer which a suspect has tried to hide or destroy, or by uncovering information in the depths of the operating system (or even in areas no longer used by the operating system) an investigator may be able to gain vital evidence. This article describes some of the methods used by investigators to uncover these types of data on Windows systems.     

Wide Range Control of Microstructure and Mechanical Properties of Carbon Nanotube Forests: A Comparison Between Fixed and Floating Catalyst CVD Techniques

Vertically aligned carbon nanotube (CNT) forests may be used as miniature springs, compliant thermal interfaces, and shock absorbers, and for these and other applications it is vital to understand how to engineer their mechanical properties. Herein is investigated how the diameter and packing density within CNT forests govern their deformation behavior, structural stiffness, and elastic energy absorption properties. The mechanical behavior of low‐density CNT forests grown by fixed catalyst CVD methods and high‐density CNT forests grown by a floating catalyst CVD method are studied by in situ SEM compression testing and tribometer measurements of force‐displacement relationships. Low‐density and small‐diameter CNT columns (fixed catalyst) exhibit large plastic deformation and can be pre‐deformed to act as springs within a specified elastic range, whereas high‐density and large‐diameter CNT columns (floating catalyst) exhibit significant elastic recovery after deformation. In this work the energy absorption capacity of CNT forests is tuned over three orders of magnitude and it is shown that CNT forest density can be tuned over a range of conventional foam materials, but corresponding stiffness is ～10× higher. It is proposed that the elastic behavior of CNT forests is analogous to open‐cell foams and a simple model is presented. It is also shown that this model can be useful as a first‐order design tool to establish design guidelines for the mechanical properties of CNT forests and selection of the appropriate synthesis method.     

England's Town Development Act: 1952: PART I: Background of the Act

The land use model recasts an unsuccessful urban form of the past. Concentric rings of declining land value begin at the intense, historic center and grade down through concentric rings to become the city plan. Little planning remains after such a model is accepted. The new freedom of the auto-age city is lost to the principle of a falling body. Further, the land use model plan restricts mobility of resident and employer by type, each to his ring Urban land value patterns are sustained by public action or inaction. A true city plan musters this power to form the best possible city.     

对于WEEE和RoHS,我们是不是找错了重点?

对于是否能找到达标的部件来满足WEEE和RoHS指令的要求,我们早已经被灌输得很多了,以至于我们忽视了一个更加重要的问题。这些指令的最终目的并不是要确保产品达标,或者开发出有效的回收计划,而是要避免使用有害物质,进而也就不需要回收计划了。