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151.
The authors investigated the relationship between transformational leadership behavior and group performance in 218 financial services teams that were branches of a bank in Hong Kong and the United States. Transformational leadership influenced team performance through the mediating effect of team potency. The effect of transformational leadership on team potency was moderated by team power distance and team collectivism, such that higher power distance teams and more collectivistic teams exhibited stronger positive effects of transformational leadership on team potency. The model was supported by data in both Hong Kong and the United States, which suggests a convergence in how teams function in the East and West and highlights the importance of team values. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
152.
153.
John Chiang 《电子产品世界》2003,(18):44-45
闪存器技术于上世纪80年代中期面世,在不到20年的时间里,就出现了迅猛增长,其应用范围从个人电脑的引导代码存储一直到近期出现的PDA、数码相机和手机中的代码和数据存储。随着移动电子的持续增长,我们对在移动电子中获得成功应用的闪存器功能和优点进行一次回顾。闪存器的历史沿革“闪存(Flash)”这一名称,是源于该存储器件只需单步操作即能擦除其中所有内容的能力。军用装备很早就从这一能力中获益,军用装备都包含机密信息,一旦即将落入敌手,就应该迅速予以破坏。与EEPROM类似,Flash的数据存储也是通过向其晶体管栅区存入电荷来实现… 相似文献
154.
Biases in social comparative judgments, such as those illustrated by above-average and comparative-optimism effects, are often regarded as products of motivated reasoning (e.g., self-enhancement). These effects, however, can also be produced by information-processing limitations or aspects of judgment processes that are not necessarily biased by motivational factors. In this article, the authors briefly review motivational accounts of biased comparative judgments, introduce a 3-stage model for understanding how people make comparative judgments, and then describe how various nonmotivational factors can influence the 3 stages of the comparative judgment process. Finally, the authors discuss several unresolved issues highlighted by their analysis, such as the interrelation between motivated and nonmotivated sources of bias and the influence of nonmotivated sources of bias on behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
155.
1Introduction Archaeologicalfindingsdatingbacktothe4thcentury BCshowedthatmissinghumanteethhavebeenreplaced bymaterialswhichincluded:animalteeth,coral,shells,ivory(elephanttusk),wood,andmetals[1].Inmodern times,autografts(boneobtainedfromanothersiteinthe … 相似文献
156.
Product optimization involves selecting design, manufacturing, and support attributes that can produce the best system. Producibility or manufacturability is the term often used to describe the relative ease of manufacturing a product. In complex systems, productibility optimization is a very difficult process, particularly when the values of many attributes are restricted by constraints. One challenge is to develop more universal producibility metrics for the conceptual design phase when design information is limited and drawings are nondimensional. This paper develops a new method for producibility optimization in conceptual design based on a combination of both decision theoretic and expert system techniques. Decision theoretic techniques provide the means to model the design for producibility problem in a manner that can deal with risk, uncertainty, and user (or corporate) preferences, and can effectively integrate diverse factors to provide a measure of the overall worth of a design. The particular decision theoretic approach employed is based on multi-attribute utility theory. An illustrative example of the methodology is applied to the conceptual design of a structural composite part. 相似文献
157.
John Tsinias 《Systems & Control Letters》1991,17(1)
In this paper we generalize the Vidyasagar's well known theorem on the local stabilizability problem of nonlinear systems using state detection [11]. Our purpose is to prove that if a system is weakly detectable and stabilizable by means of a continuous state feedback u = γ(x), for which no differentiability assumption is imposed, then the system is also stabilized by the law u = γ(z), where z is the output of a weak detector for the state x. The result above is applicable to several cases not covered by other works. 相似文献
158.
Acid Green 25, which is a diazoic dye bearing two sulfonic groups, is efficiently sorbed on chitosan. The protonation of chitosan may explain the electrostatic attraction of this anionic dye and that its optimum pH is close to 3. Preliminary protonation of amine groups (obtained by contact with a sulfuric acid solution) reduced the variation of solution pH following sorbent addition but significantly reduced sorption performance: the maximum sorption capacity of raw chitosan, 525 mg dye/g (0.84 mmol dye/g), was halved by acidic preconditioning. The acidic conditioning also reduced the kinetic rate—the time necessary to reach equilibrium increased up to threefold depending on the experimental conditions. The size of sorbent particles influenced sorption kinetics and equilibrium because of resistance to intraparticle diffusion, but the sorption appeared to occur not only at the surface of the sorbent but also in the intraparticle network of the polymer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1073–1080, 2003 相似文献
159.
John R. Clem Zhidong Hao Ljiljana Dobrosavljević-Grujić Zoran Radović 《Journal of Low Temperature Physics》1992,88(3-4):213-219
We present a generalized variational model of an isolated vortex, valid in the anisotropic case when the external magnetic field is along one of the symmetry directions. We discuss the effects of the field anisotropy on the core and magnetic pinning of individual vortices. 相似文献
160.
John McCarthy 《International Planning Studies》2004,9(1):43-64
The emergence of new tourism‐related land uses within historic port cities has brought a range of physical, economic and social benefits. However, there are often associated tensions between the need for economic development and the need to maintain the unique heritage resource that may be a large part of the attraction for visitors. The case of Malta's Cottonera Project—for the waterfront of part of the historic ‘Grand Harbour’—throws these tensions into sharp relief; indeed, the controversy generated by the proposal led to a successful vote of no confidence in the Maltese government. The case illustrates the problematic role of the spatial planning system in seeking to mediate between interests with opposing aims in historic port cities, and the need to apply principles of sustainable regeneration. 相似文献