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991.
Examined the job performance of 420 credit managers (mean age at hiring 25 yrs) from a large finance company who either quit their job, were fired, or were promoted to a higher position in the company. Six biographical variables and 12 performance appraisal scores accumulated from data in employee files were used in a cross-validated multiple discriminant analysis to predict membership in the 3 classification groups. Results reveal a systematic relation between the performance appraisal variables and the classification groups: The performance of promoted Ss was significantly superior to that of Ss who quit, which in turn was significantly superior to the performance of the fired Ss. 18 discriminating variables accounted for a 46.7% hit rate in group membership. Findings are discussed in the context of research on performance antecedents of voluntary and involuntary turnover, as well as the feedback properties of performance appraisal information. It is suggested that no single performance–turnover relation exists. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
On navigating between friends and foes 总被引:1,自引:0,他引:1
Kiryati N. Bruckstein A.M. 《IEEE transactions on pattern analysis and machine intelligence》1991,13(6):602-606
The problem of determining the optimal straight path between a planar set of points is considered. Each point contributes to the cost of a path a value that depends on the distance between the path and the point. The cost function, quantifying this dependence, can be arbitrary and may be different for different points. An algorithm to solve this problem using an extension of the Hough transform is described. The range of applications includes straight-line fitting to a set of points in the presence of outliers, navigation, and path planning. The proposed extended Hough transform can be tuned to equivalent to well-known robust least-squares techniques, and allows efficient, approximate M -estimation 相似文献
993.
In this study, an analytical model is developed to include the effect of material fracture on the overall behavior of a structure. The continuum damage mechanics approach is used to describe the continuous deterioration of the material stiffness that leads to total failure. The damage evolution is assumed to be anisotropic and the effect of the triaxiality of stress on the fracture criterion is included in the analysis. The above modifications were applied to an existing finite element program which is capable of including both geometric and material nonlinearities in the analysis. The program was used to analyze a welded tubular connection (T-joint). This joint was chosen because fracture was shown experimentally to control its ultimate behavior. Solid finite elements were used to model the chord and the branch in the intersection region, wedge elements were used for the weld profile, and the rest of the geometry was modeled using shell elements. The joint was subjected to an increasing amount of displacement at the far end of the branch. The loading was continued until total failure. During this process, the evolution of the damage and its propagation were monitored. Divergence of the solution was obtained at a failure load of 42.4 kips compared to 44.0 kips obtained experimentally. In addition, the failure mode of the joint predicted by the analysis was identical to that observed experimentally. 相似文献
994.
Abstract. The estimation of the spectral density function of a stationary Gaussian process at the input of an instantaneous nonlinearity is considered when the nonlinearity is known and a finite set of observations of the output process is given. A class of spectral estimates is considered and their quadratic-mean consistency is established; precise asymptotic expressions for their bias and covariance are derived and their asymptotic normality is obtained. 相似文献
995.
T.F. Zabel 《臭氧:科学与工程》1985,7(1):11-30
Only two water works in the UK apply ozone at present as part of their treatment, onefor taste and odor control and theother forcolor removal. Forthetwo applicationus ozone was the most economical option at thetime theplants were installed andozone has been successful for the purpose for which it was designed. 相似文献
996.
S. O. Slesarevskii A. M. Belavskii M. N. Korotenko V. S. Lyubarskii V. P. Pavlenko V. A. Snigerev A. V. Tkachenko 《Atomic Energy》1989,67(5):853-855
Translated from Atomnaya Énergiya, Vol. 67, No. 5, pp. 358–359, November, 1989. 相似文献
997.
998.
A new learning model for real-time, grey-level image segmentation is presented. The model gives excellent results for images with different shapes. 相似文献
999.
1000.
During a core melt accident, a pressurization of the containment has to be expected, which could lead to a failure of the containment due to overpressurization. This failure mode is expected to be the most likely one for large dry containments under accident conditions. Also during a core melt accident, a large quantity of hydrogen may be generated, giving the potential of a loss of containment integrity due to violent hydrogen combustion. Timely venting of the containment atmosphere can prevent overpressurization and may perhaps make the hydrogen situation in the containment less severe. This paper discusses the thermodynamic consequences of different vent strategies for a large German PWR during core melt accidents. 相似文献