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71.
It is no secret that Microsoft Windows NT is the hacker’s favourite Operating System (OS). According to defacement-tracking site Attrition.org, (www.Attrition.org) Windows NT received 54.41% of all recorded OS attacks between August 1999 and April 2001. In stark contrast, some of the lesser-known Operating Systems made up for as little as 0.1% of all OS attacks. However, despite the huge difference in the quantity of attacks, companies that employ the lesser-known systems may be at greater risk…  相似文献   
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73.
193 randomly selected adults completed a structured interview concerning their values, beliefs, attitudes, experiences, and intentions concerning information-privacy issues involving 6 types of organizations such as employers, law enforcement agencies, and the Internal Revenue Service. Results indicate that higher valuations of informational privacy were related to lower feelings of control over personal information, less satisfaction with their perceived degree of control, and less willingness to participate in a subsequent interview. Information-privacy beliefs and attitudes varied with the type of organization under consideration. Implications are discussed in terms of organizational and societal policy concerning the treatment of information about individuals. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
Studied the conditions under which failure would enhance or inhibit subsequent task performance. Based on the theory of C. B. Wortman and J. W. Brehm (1975), it was expected that small amounts of failure would produce reactance (manifested by improved performance at a subsequent task); large amounts would lead to learned helplessness (i.e., impaired later performance). It was further expected that individual differences in self-esteem and private self-consciousness would serve as moderator variables for the effects. In Exp I, 78 college students were exposed to either a small amount or no failure before working on an anagrams task. As predicted, Ss high in self-consciousness, who showed greater reactance arousal in attitude change studies, performed better on the anagrams task than Ss low in self-consciousness in the small-failure condition, but not in the no-failure condition. In Exp II, 119 Ss were pretreated with either a small amount of failure, an extended amount of failure, or no failure before working on the task. A significant Self-Esteem by Helplessness Training interaction emerged. Low self-esteem Ss (low SEs) performed marginally better than did high SEs in the small-failure condition but significantly worse than high SEs in the extended-failure condition. Questionnaire data from Exp II were consistent with the notion that enhanced performance reflected reactance, whereas impaired performance signified helplessness. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
In this work, the authors explored how a person's view of himself or herself might determine his or her use of power in a complex dispute resolution negotiation. In 3 studies of asymmetric power in negotiations, the authors demonstrated that the impact of power on motivation and behavior is moderated by both a person's self-view and the social context. In Study 1, the results revealed that in a one-on-one dispute, powerful individuals primed to hold an interdependent (as opposed to independent) self-construal are more generous in resolving their disputes with low-powered opponents. Study 2 replicated this finding but revealed a different pattern in intergroup disputes, in which powerful interdependent teams of negotiators are actually less generous than are independent teams. Study 3 provided a conceptual replication of Study 2, with the use of chronic measures of self-construal and self-reported measures of behavior. Results suggest that an interdependent self-construal may lead to a more benevolent use of power in dyadic conflicts but more exploitive uses of power in intergroup conflicts. Implications for the understanding of power and self-construal are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
Model-based face analysis is a general paradigm with applications that include face recognition, expression recognition, lip-reading, head pose estimation, and gaze estimation. A face model is first constructed from a collection of training data, either 2D images or 3D range scans. The face model is then fit to the input image(s) and the model parameters used in whatever the application is. Most existing face models can be classified as either 2D (e.g. Active Appearance Models) or 3D (e.g. Morphable Models). In this paper we compare 2D and 3D face models along three axes: (1) representational power, (2) construction, and (3) real-time fitting. For each axis in turn, we outline the differences that result from using a 2D or a 3D face model.  相似文献   
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78.
Cartan's method of equivalence is applied to the problem of equivalence of 2-state systems with scalar control under feedback. The differential invariants produced by the method completely characterize equivalence classes. The phenomenon of linearizability is associated with the presence of infinite Lie pseudogroups. The generic non-linearizable case has a geometrically defined variational problem which yields a time optimal closed loop control.  相似文献   
79.
Benefit/cost methodologies are well accepted for project analysis from a national perspective. Recent pressure to develop local decisionmaking and local funding for water projects has focused attention on the regional costs and benefits of such development. This paper examines some methodological issues that emerge as one attempts to estimate these regional costs and benefits. Uncritical use of regional economics procedures and concepts such as input-output analysis and value added to measure the primary and secondary impacts of these projects carries the risk of seriously overestimating regional project benefits. The paper concludes that new approaches to regional project analysis must be developed that will reconcile and incorporate regional economics procedures with benefit/cost methodology.  相似文献   
80.
In confined pig herds, located in Northwest-Germany and affiliated to a hybrid breeding organisation, 3 retrospective observational studies were performed to study the effects of "meteorological seasons" on sow fertility. A subsequent field trial was performed to study the effects of photoperiod and of temperature on sow fertility separately. Associations of economically important fertility disorders and season resp. climate categories were determined by adjusted Relative Risks in stratified analysis (observational studies), or by Odds Ratios in the Multiple Logistic Regression Analysis (field trial). Due to nonconsistent seasonal findings in the observational studies and a lack of temperature or photoperiod effects in the field trial we conclude that season and its main contributing climatic factors had no substantial effects on sow fertility in the well-managed herds of our climate zone. Nonclimatic risk factors for the so-called "Summer Infertility Syndrome" are discussed.  相似文献   
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