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11.
In this time of flat, team-based and technology-enabled organizations the effectiveness of communication and team leadership practices will be more important than ever before. Therefore, we believe that some of the earlier, time-tested classic works on group dynamics and leadership are worthy of re-reading. We are particularly impressed by how relevant one of the oldest classics, Benne and Sheats' (1948) article on functional roles of group members, remains to this day. 相似文献
12.
In this work a new class of numerical methods for the BGK model of kinetic equations is presented. In principle, schemes of
any order of accuracy in both space and time can be constructed with this technique. The methods proposed are based on an
explicit–implicit time discretization. In particular the convective terms are treated explicitly, while the source terms are
implicit. In this fashion even problems with infinite stiffness can be integrated with relatively large time steps. The conservation
properties of the schemes are investigated. Numerical results are shown for schemes of order 1, 2 and 5 in space, and up to
third-order accurate in time. 相似文献
13.
JP Heiner SS Kohles PA Manley R Vanderby MD Markel 《Canadian Metallurgical Quarterly》1997,(341):233-240
In a canine model, the fixation stability of a prosthesis and proximal bone graft composite were measured relative to the distal femur. One group had the prosthesis graft composite cemented into the distal femur. The second group had the prosthesis graft composite press fit into the distal femur for biologic ingrowth. Displacements of the proximal femoral grafts relative to the host bone in each group were measured after ex vivo (acute with graft) implantation and 4 months after implantation. A third group with no osteotomy (acute intact) simulated perfect graft to host bone union. Relative displacements representing 6 degrees freedom (translation and rotation) were calculated from the displacement values measured by 9 eddy current transducers. Measurements of displacement were used to test the hypothesis that distal press fit fixation equals distal cement fixation at 4 months after implantation. In all cases the measured translations and rotations of the graft to implant construct were small and of a magnitude that should encourage bone ingrowth (< 0.05 mm and < 0.1 degree, respectively). The stability of the press fit group at 4 months was not significantly different from the cemented group in axial and transverse displacement during axial and transverse loading, respectively. There was no difference in stabilities at 4 months between distal press fit and cemented fixation in hip replacements requiring a proximal femoral graft. 相似文献
14.
Stress in the parenting role has been found to be related to family functioning and parenting behavior. However, most research in this area has been conducted with clinical samples and has not compared parenting stress of mothers and fathers. In this study, 589 married couples with young children (12 to 60 months old) completed the Parenting Stress Index-Short Form (Abidin, 1990) and measures of child-rearing behaviors and attitudes, social support, and child behavior. The validity of Abidin's measure and theoretical model was tested, and results were mixed. Small effects were found for mothers and fathers, and these were moderated by child age and marital happiness. Stress as a normal consequence of parenting is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
15.
Sandra A. Yost Peter H. Bauer Kasyapa Balemarthy 《Multidimensional Systems and Signal Processing》1996,7(2):211-220
This paper addresses the BIBO (bounded-input bounded-output) stability of a class of discrete 2-D quarter-plane filters in the presence of nonessential singularities of the second kind (NSSK's) on the unit bidisk. Conditions under which the double bilinear transformation (DBT) preserves stability are derived. The results presented here also extend the class of systems whose stability can be predicted. Use of the inverse DBT to produce a continuous equivalent of the discrete 2-D transfer function allows easy application of a continuous-domain equivalent of a criterion developed by Dautov. The necessary and sufficient condition for stability derived in this work provides a simple check for the class of systems under consideration. From this class of systems, it is also possible to construct stable pairs of mutually inverse transfer functions. 相似文献
16.
This article describes the application, at the team and individual level, of findings from the positive psychology research. An overview of this research is presented focusing on several areas generally included in the positive psychology domain: flow, appreciative inquiry, the broaden and build theory, and other strategies for increasing the experience of positive emotions and the identification and deployment of strengths. The authors propose that these applications show promise in consulting psychology engagements and may have merit when utilized by practitioners themselves. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
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
18.
Myers Mark G.; MacPherson Laura; McCarthy Denis M.; Brown Sandra A. 《Canadian Metallurgical Quarterly》2003,15(2):163
The goal of the present studies was to construct and validate a short form of the 50-item Smoking Consequences Questionnaire (SCQ; T. H. Brandon & T. B. Baker, 1991), a measure of smoking outcome expectancies. In Study 1, a 21-item short form (S-SCQ) was derived from a sample of 107 young adults previously treated for substance abuse. In Study 2, the measure was cross-validated on 125 adolescents in treatment for substance abuse. Confirmatory factor analyses revealed good model fit and factorial invariance for the 4 S-SCQ subscales across both samples. Validation analyses on each sample found that subscale scores generally correlated significantly with smoking-related variables. The present studies provide initial evidence for the utility of the S-SCQ when used with young adults and adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
Giuseppe G. G. Manzardo Sandra Kürsteiner-Laube und Daniel Perrin 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,203(6):501-506
In diethyl ether extracts from celeriac (Apium graveolens L. var.rapaceum) all four stereoisomers of (3a–7a)-cis-3-butylhexahydrophthalide were found to be present. The analyses were carried out by means of GC, enantioselective GC and GC-MS. The assignment of the relative configuration of the diastereomers3 and4 was accomplished by NOE difference spectroscopy. 相似文献
20.
Kindermann Sandra S.; Matteo Terrence M.; Morales Eduardo 《Canadian Metallurgical Quarterly》1993,24(2):224
A training-needs assessment was conducted at California School of Professional Psychology, Berkeley/Alameda, on students' beliefs about clinical competence, past training in HIV issues, and future training needs at the school. They perceived themselves to be somewhat competent in providing clinical services to HIV patients and members of groups at high risk for HIV. A modest correlation was found between the students' total HIV training and perceived competence, but none was found between the multicultural emphasis in HIV education and their perceived competence. These findings suggest an ethical dilemma surrounding inadequately trained psychologists providing services to multicultural populations. Ethical issues concerning training standards and criteria for clinical competency are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献