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91.
Conducted a comprehensive meta-analysis based on 665 validity coefficients across 576,460 data points to investigate whether integrity test validities are generalizable and to estimate differences in validity due to potential moderating influences. Results indicate that integrity test validities are substantial for predicting job performance and counterproductive behaviors on the job, such as theft, disciplinary problems, and absenteeism. The estimated mean operational predictive validity of integrity test for predicting supervisory ratings of job performance is .41. Results from predictive validity studies conducted on applicants and using external criterion measures (i.e., excluding self-reports) indicate that integrity tests predict the broad criterion of organizationally disruptive behaviors better than they predict employee theft alone. Despite the influence of moderators, integrity test validities are positive across situations and settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
The mechanisms of carrier transfer from barrier regions (superlattices, side-wall and vertical quantum wells) into arrays of quantum wires are investigated by time-resolved photoluminescence. The wires are grown by different techniques on V-groove substrates. The transfer times range from 25 to 900 ps, depending on the details of the whole structure. The fast carrier transfer is modeled by a diffusion equation which allows one to estimate the quantum mechanical capture time from a two-dimensional vertical QW into a one-dimensional QWR to be <2 ps.  相似文献   
93.
From dust till drawn   总被引:1,自引:0,他引:1  
We present a system for drawing pastel media in real-time as an effective alternative to most existing digital solutions that basically allow for drawing arbitrary strokes in a particular style. Our approach is focused on the simulation of the natural material itself and on its interaction with the drawing surface and the drawing tool. Upon free-form drawing, a bidirectional transfer of pigment takes place. In one direction, the paper surface is dusted with new pigment particles broken off the tip (i.e., the end of the drawing tool). A large part of these particles will be deposited or blended together with previously deposited ones whereas the remainder does not contribute to the drawing and is blown off. On the other hand, a certain amount of previously deposited pigment is scraped off and picked up again soiling the tip. This is noticeable in the next strokes to be drawn. Furthermore, both the tip and the paper surface are subject to weathering depending on the exerted pressure and friction of the drawing tool, and the bumpiness of the paper. As a result, the paper surface becomes slightly damaged, limiting the deposition of new pigment. The tip, on the other hand, becomes blunt making new strokes wider. From a stylistic point of view, similarly to traditional drawings our results convey the artists’ characteristics (e.g., the way of wielding the brush, skillfulness, feeling for the medium). Therefore, we believe that our system allows an artist to create realistically looking pastel images without losing his/her personal touch.  相似文献   
94.
In Deutschland geh?rt der Einsatz von NEDAP-Wahlcomputern in immer mehr Gemeinden zum Alltag. Durch Untersuchungen zur Sicherheit und Manipulierbarkeit konnten Erkenntnisse gewonnen werden, mit welchen Methoden manipulierte Software in den Wahlcomputer eingebracht und Hardwarekomponenten ausgetauscht werden k?nnen. Dadurch ist erstmals eine Beurteilung der Eignung der NEDAP-Wahlcomputer hinsichtlich der Anforderungen an manipulationsfeste, nachvollziehbare und transparente Wahlen m?glich.  相似文献   
95.
CMOS scaling into the nanometer regime   总被引:11,自引:0,他引:11  
Starting with a brief review on 0.1-μm (100 nm) CMOS status, this paper addresses the key challenges in further scaling of CMOS technology into the nanometer (sub-100 nm) regime in light of fundamental physical effects and practical considerations. Among the issues discussed are: lithography, power supply and threshold voltage, short-channel effect, gate oxide, high-field effects, dopant number fluctuations and interconnect delays. The last part of the paper discusses several alternative or unconventional device structures, including silicon-on-insulator (SOI), SiGe MOSFET's, low-temperature CMOS, and double-gate MOSFET's, which may lead to the outermost limits of silicon scaling  相似文献   
96.
A circuit is described that determines the average of the transit time of light from an event in a scintillation counter to the two ends of that counter. The design offers superior time resolution and a novel gating scheme that significantly reduces circuit dead-time.  相似文献   
97.
In general, the performance of a KE penetrator against most targets increases with velocity regardless of the particular penetrator-target interaction mode. It is possible to show that there exists an optimum velocity which maximizes the performance of an impacting penetrator for a given expenditure of kinetic energy. Simple graphical methods are described that determine the optimum velocity from general performance-velocity plots. These graphical methods may also be applied to experimental data alone. In addition, simple analytic models which describe the velocity dependent penetration/perforation performance of KE penetrators are examined and extended. These models may be used to explicitly assess the influence of parameters such as target strength and density and penetrator mass, strength and density. For some of the models in this analysis, the explicit relations between the optimum striking velocity for a specific kinetic energy value and the penetrator-target parameters are described.  相似文献   
98.
Much of what has been written in Australia about the protection of computer programs has been inspired by high profile cases concerning the boundaries of copyright protection. The Australian law firm Clayton Utz says that there has been little discussion about other types of legal protection for computer programs, and as a consequence, other intellectual property laws should not be overlooked.  相似文献   
99.
Background, prime influences upon present day methods and current trends in United Kingdom tendering practices are reviewed. Significant weaknesses are identified, confirming the need for some revision of existing contractor selection methods. The findings compliment recommendations of the recent government/industry review of the construction sector headed by Sir Michael Latham. Specifically, that tendering procedure should embrace investigation of contractors' potential to deliver a service of acceptable standard, on time, within budget. Present selection methods often fail in this objective, being inclined to discriminate predominantly on cost.  相似文献   
100.
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