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61.
The differential effectiveness of group psychotherapy was estimated in a meta-analysis of 111 experimental and quasi-experimental studies published over the past 20 years. A number of client, therapist, group, and methodological variables were examined in an attempt to determine specific as well as generic effectiveness. Three different effect sizes were computed: active versus wait list, active versus alternative treatment, and pre- to posttreatment improvement rates. The active versus wait list overall effect size (0.58) indicated that the average recipient of group treatment is better off than 72% of untreated controls. Improvement was related to group composition, setting, and diagnosis. Findings are discussed within the context of what the authors have learned about group treatment, meta-analytic studies of the extant group literature, and what remains for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
A. Campillo J. I. Farran M. J. Pisabarro 《Applicable Algebra in Engineering, Communication and Computing》2007,18(1-2):191-203
We use the special geometry of singular points of algebraic differential equations on the affine plane over finite fields
to study the main features and parameters of error correcting codes giving by evaluating functions at sets of singular points.
In particular, one gets new methods to construct codes with designed minimum distance.
This work was partially supported by MCyT BFM2001-2251. 相似文献
63.
A new approach to study ergodicity of filtering processes is presented. It is based on the vanishing discount approach to discounted functional of filtering process. We show that limit superior of the Cesaro averages of the functionals is the same for all initial conditions from which the uniqueness of invariant measures of filtering processes follows. The approach is based on certain assumption for which we provide a sufficient condition using concavity arguments. In addition we show the existence of solutions to the Poisson equation corresponding to filtering process with concave functional. The assumptions are then extended to the controlled case and using similar concave arguments we obtain the existence of solutions to the Bellman equation corresponding to partially observed average cost per unit time problem. 相似文献
64.
The numerical simulation of comparative elastohydrodynamic lubrication between axisymmetrical and 3D elastic approaches on the radial lip seals is presented in order to determine the 3D effect of the elastic aspect of the seal lip. Indeed, the consideration of 3D model in other words the circumferential variation of the lip elastic deformation indicated a difference in the deformation distribution of the lip compared to the axisymmetrical approach. Consequently, the results show that the presence of the circumferential variation of the seal lip deformation has a significant effect on the pumping rate values. 相似文献
65.
本文应用d'Alembert-Lagrange原理,对由基座、(n-1)个柔性连杆及端部负载组成,相互用柱铰连接的柔性链式多体系统进行建模;对在空间技术中,具有一刚杆,两柔杆加上刚性负载所组成的三维机械臂系统,采用Gear算法进行数值仿真。仿真结果比较符合实际,从而在柔性多体系统的数学模型为刚性常微分方程的情况下,为解决其数值仿真问题,特别是三维问题的数值仿真取得了进展。 相似文献
66.
67.
A. T. Sousa P. S. Fialho C. A. Nieto de Castro R. Tufeu B. Le Neindre 《International Journal of Thermophysics》1996,17(3):551-560
The density of HCFC 141b has been measured at several temperatures between 260 and 320 K, Mid pressures up to 20 MPa, with a mechanical oscillator densimeter. The densimeter was calibrated with 2,2,4-trimethylpentane, whose density was obtained from a correlating cyuation with 0.3% uncertainty. The density data obtained for HCFC 14H) hits a reproducibility of 0.05% and an uncertainty of 0.3%. The data obtained were fitted to a Tait-type equation. which reproduced the experimental densities within 0.11 % and were compared with the data obtained in other works.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994, Boulder, Colorado, U.S.A. 相似文献
68.
论述作为一种新型发光器件的MIM隧道结的发光机理,报告了该器件的发光现象和I-V特性曲线中负阻现象的实验观察。数据显示,结中表面等离极化激元(SPP)与粗糙度的耦合是引起光发射的主要方面,SPP对隧穿电子的阻塞作用导致了电子输运中的负阻现象。此外,还观察到了直接辐射的紫外峰。 相似文献
69.
70.