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41.
De Cremer David; van Knippenberg Daan; van Dijke Marius; Bos Arjan E. R. 《Canadian Metallurgical Quarterly》2006,10(3):233
In the present research, we examine whether leader's self-sacrifice positively influences followers' self-esteem and whether followers' identification with the collective plays a role in this process. It was predicted that leader self-sacrifice would influence followers' self-esteem, but particularly so when followers exhibited strong (vs. weak) collective identification. Results from an organizational survey showed that leader self-sacrifice and collective identification interacted in predicting follower self-esteem, such that followers' self-esteem was higher when they identified strongly with the collective and when the leader was self-sacrificial (vs. self-benefiting). An experimental scenario study replicated this interactive effect between collective identification and leader's self-sacrifice on followers' self-esteem and also showed that this effect was (at least partly) mediated by followers' perceptions of whether the leader respected and valued the group. Implications with respect to the relationship between self-sacrifice and self-esteem are outlined, and possible integrations of leader self-sacrifice, identity, and empowerment are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
Decay Rates for a Beam with Pointwise Force and Moment Feedback 总被引:4,自引:0,他引:4
Kais Ammari Zhuangyi Liu Marius Tucsnak 《Mathematics of Control, Signals, and Systems (MCSS)》2002,15(3):229-255
We consider the Rayleigh beam equation and the Euler–Bernoulli beam equation with pointwise feedback shear force and bending
moment at the position ξ in a bounded domain (0,π) with certain boundary conditions. The energy decay rate in both cases is
investigated. In the case of the Rayleigh beam, we show that the decay rate is exponential if and only if ξ/π is a rational
number with coprime factorization ξ/π=p/q, where q is odd. Moreover, for any other location of the actuator we give explicit polynomial decay estimates valid for regular initial
data. In the case of the Euler–Bernoulli beam, even for a nonhomogeneous material, exponential decay of the energy is proved,
independently of the position of the actuator.
Date received: October 30, 2000. Date revised: December 20, 2001. 相似文献
43.
Automatic writer identification using connected-component contours and edge-based features of uppercase Western script 总被引:1,自引:0,他引:1
Schomaker L Bulacu M 《IEEE transactions on pattern analysis and machine intelligence》2004,26(6):787-798
In this paper, a new technique for offline writer identification is presented, using connected-component contours (COCOCOs or CO3s) in uppercase handwritten samples. In our model, the writer is considered to be characterized by a stochastic pattern generator, producing a family of connected components for the uppercase character set. Using a codebook of CO3s from an independent training set of 100 writers, the probability-density function (PDF) of CO3s was computed for an independent test set containing 150 unseen writers. Results revealed a high-sensitivity of the CO3 PDF for identifying individual writers on the basis of a single sentence of uppercase characters. The proposed automatic approach bridges the gap between image-statistics approaches on one end and manually measured allograph features of individual characters on the other end. Combining the CO3 PDF with an independent edge-based orientation and curvature PDF yielded very high correct identification rates. 相似文献
44.
180 Charles River rats were conditioned by pairing consumption of a novel sodium saccharin drinking solution with the effects of an ip injection of 75 mg/kg cyclophosphamide, an immunosuppressive drug. Five and 10 days after conditioning, an experimental group (Group CS) was reexposed to the saccharin drinking solution. Control Ss (Group CSo) were conditioned but were not reexposed to saccharin. On Days 10, 15, or 25 after conditioning, Ss were injected ip with sheep erythrocytes, and independent subgroups were sampled for hemagglutinating antibody titer 4, 6, or 8 days later. Antibody titers 4 days after immunization were lower than values observed 6 and 8 days after immunization, and CS Ss had an attenuated antibody response. There were no significant differences between Group CSo and a group of placebo-treated Ss, but CS Ss had lower antibody titers than placebo-treated animals 4, 6, and 8 days after antigenic stimulation. Results suggest that reexposure to a CS may have long-lasting effects, and provide further documentation of conditioned immunopharmacologic effects and the impact of behavioral factors in modifying immunologic reactivity. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
This article reviews the early days of an Australian public broadcaster's open studio Web project. It raises important issues for software developers and Web media makers about the need for software and collaborative structures that can facilitate community building in an open and responsive way. This project could be of interest to software developers working in Drupal. 相似文献
46.
Abstract. This paper presents the findings of a longitudinal study of the Slovenian company Sava during its 1995–2004 transition period when it adapted to and prospered in a free market economy. The company is particularly interesting because of its successful transition from a socialist company operating in a protected market to a privatized company operating in a capitalist global market, as well as the pivotal role of information technology (IT)-supported organizational learning that brought about radical change and successful transition. Our investigation of Sava's experiences demonstrates how the company's increasing attention to organizational learning, integration of working and learning, and its constant innovation of products and processes created new needs for IT support that motivated the adoption of new IT systems (such as Lotus Notes, document management systems, SAP), which in turn increased Sava's capacity to learn. Furthermore, our study reveals how the role of IT systems in organizational learning depends on the nature of learning (single-loop, double-loop or triple-loop learning) and the organizational level at which learning takes place (individual, group/department or organization). By providing insight into the emergence of distinct types of IT-supported learning and their vital role in Sava's successful transition, the paper contributes to a deeper understanding of the relationship between IT and organizational learning that is relevant and inspiring to other companies, especially those operating in transition economies. 相似文献
47.
Evaluation of optimization methods for nonrigid medical image registration using mutual information and B-splines. 总被引:3,自引:0,他引:3
Stefan Klein Marius Staring Josien P W Pluim 《IEEE transactions on image processing》2007,16(12):2879-2890
A popular technique for nonrigid registration of medical images is based on the maximization of their mutual information, in combination with a deformation field parameterized by cubic B-splines. The coordinate mapping that relates the two images is found using an iterative optimization procedure. This work compares the performance of eight optimization methods: gradient descent (with two different step size selection algorithms), quasi-Newton, nonlinear conjugate gradient, Kiefer-Wolfowitz, simultaneous perturbation, Robbins-Monro, and evolution strategy. Special attention is paid to computation time reduction by using fewer voxels to calculate the cost function and its derivatives. The optimization methods are tested on manually deformed CT images of the heart, on follow-up CT chest scans, and on MR scans of the prostate acquired using a BFFE, T1, and T2 protocol. Registration accuracy is assessed by computing the overlap of segmented edges. Precision and convergence properties are studied by comparing deformation fields. The results show that the Robbins-Monro method is the best choice in most applications. With this approach, the computation time per iteration can be lowered approximately 500 times without affecting the rate of convergence by using a small subset of the image, randomly selected in every iteration, to compute the derivative of the mutual information. From the other methods the quasi-Newton and the nonlinear conjugate gradient method achieve a slightly higher precision, at the price of larger computation times. 相似文献
48.
49.
De Cremer David; Brockner Joel; Fishman Ariel; van Dijke Marius; van Olffen Woody; Mayer David M. 《Canadian Metallurgical Quarterly》2010,95(2):291
Prior research has shown that procedural fairness interacts with outcome fairness to influence employees’ work attitudes (e.g., organizational commitment) and behaviors (e.g., job performance, organizational citizenship behavior), such that employees’ tendencies to respond more positively to higher procedural fairness are stronger when outcome fairness is relatively low. In the present studies, we posited that people’s uncertainty about their standing as organizational members would have a moderating influence on this interactive relationship between procedural fairness and outcome fairness, in that the interactive relationship was expected to be more pronounced when uncertainty was high. Using different operationalizations of uncertainty of standing (i.e., length of tenure as a proxy, along with self-reports and coworkers’ reports), we found support for this hypothesis in 4 field studies spanning 3 different countries. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Building on fairness heuristic theory, fairness theory, and trust development models, we argue that unfairly enacted procedures decrease followers' trust in the authority particularly when authorities have high power over their followers. Moreover, we expected trust to mediate procedural fairness effects on followers' attitudes (authorities' legitimacy and charisma attributed to authorities) and organizational citizenship behavior. Procedural fairness effects on these variables, as mediated by trust, should therefore also be stronger when authority power is high. The results of a single- and multisource field study and a laboratory experiment supported these predictions. These studies support the role of authority power as a theoretically and practically relevant moderator of procedural fairness effects and show that its effectiveness is explained through trust in authorities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献