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951.
Cooper M. Lynne; Wood Phillip K.; Orcutt Holly K.; Albino Austin 《Canadian Metallurgical Quarterly》2003,84(2):390
Longitudinal data from a representative sample of 1,978 Black and White adolescents were used to examine the role of personality in multiple risk or problem behaviors. Results indicate that covariation among diverse behaviors (educational underachievement, delinquent behavior, substance use, sexual behavior) can be adequately modeled by a single higher order factor, and that impulsivity and avoidance coping serve as generalized risk factors for involvement in these behaviors. Whereas none of the personality variables examined explained change in problem behaviors once established, avoidance coping prospectively predicted involvement among a subgroup of adolescents with little or no prior involvement. Results suggest that dysfunctional styles of regulating emotions and emotionally driven behaviors are core features of risky or problem behaviors during adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
952.
V. V. Emtsev P. Ehrhart D. S. Poloskin K. V. Emtsev 《Journal of Materials Science: Materials in Electronics》2007,18(7):711-714
Production processes of electrically active defects in degenerate silicon subjected to 2.5 MeV electron irradiation at T = 4.2 K and T = 300 K have been studied. The production rates of primary and secondary defects in irradiated samples are analyzed on the basis
of the known properties of radiation-produced defects in Si. It has been demonstrated that a striking difference in the production
rates of electrically active defects in n- and p-Si under irradiation at cryogenic temperatures may be related to the different
fate of Frenkel pairs in both materials. The production rate of primary defects in degenerate Si was found to be between 1.5 cm−1 and 2 cm−1. 相似文献
953.
Optical Splitting Trees for High-Precision Monocular Imaging 总被引:1,自引:0,他引:1
McGuire M. Matusik W. Pfister H. Chen B. Hughes J.F. Nayar S.K. 《Computer Graphics and Applications, IEEE》2007,27(2):32-42
In this article, we consider the design of monocular multiview optical systems that form optical splitting trees, where the optical path topology takes the shape of a tree because of recursive beam splitting. Designing optical splitting trees is challenging when it requires many views with specific spectral properties. We introduce a manual design paradigm for optical splitting trees and a computer-assisted design tool to create efficient splitting-tree cameras. The tool accepts as input a specification for each view and a set of weights describing the user's relative affinity for efficiency, measurement accuracy, and economy. An optimizer then searches for a design that maximizes these weighted priorities. Our tool's output is a splitting-tree design that implements the input specification and an analysis of the efficiency of each root-to-leaf path. Automatically designed trees appear comparable to those designed by hand; we even show some cases where they are superior. With the help of the optimizer, the system demonstrates high dynamic range, focusing, matting, and hybrid imaging implemented on a single, reconfigurable camera containing eight sensors 相似文献
954.
Sankaralingam K. Nagarajan R. Haiming Liu Changkyu Kim Jaehyuk Huh Burger D. Keckler S.W. Moore C. 《Micro, IEEE》2003,23(6):46-51
The Tera-op reliable intelligently adaptive processing system (TRIPS) architecture seeks to deliver system-level configurability to applications and runtime systems. It does so by employing the concept of polymorphism, which permits the runtime system to configure the hardware execution resources to match the mode of execution and demands of the compiler and application. 相似文献
955.
956.
Summary A simply supported beam with fixed ends and an attached strongly nonlinear spring is considered. As the forced bending vibrations
of the beam have moderate amplitudes, the stretching force is a nonlinear function of the deflection. The vibrations are presented
as a series with respect to the modes of the beam without attachment. Applying the Bubnov-Galerkin procedure, an infinite
system of ordinary differential equations is derived. Using the multiple scales method, the quasiperiodic vibrations in the
region of the combination resonance are analyzed in the paper. The system vibrations, when the nonlinear spring is attached
in different points, are analyzed. Applicability of the nonlinear spring for mitigation of a combination resonance is discussed. 相似文献
957.
This study provides a meta-analysis of research on the associations between relationship conflict, task conflict, team performance, and team member satisfaction. Consistent with past theorizing, results revealed strong and negative correlations between relationship conflict, team performance, and team member satisfaction. In contrast to what has been suggested in both academic research and introductory textbooks, however, results also revealed strong and negative (instead of the predicted positive) correlations between task conflict, team performance, and team member satisfaction. As predicted, conflict had stronger negative relations with team performance in highly complex (decision making, project, mixed) than in less complex (production) tasks. Finally, task conflict was less negatively related to team performance when task conflict and relationship conflict were weakly, rather than strongly, correlated. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
958.
B. Dagens A. Martinez D. Make O. Le Gouezigou J.-G. Provost V. Sallet K. Merghem J.-C. Harmand A. Ramdane B. Thedrez 《Photonics Technology Letters, IEEE》2005,17(5):971-973
Among the new semiconductor materials for telecom devices, the GaInNAs-GaAs structure presents interesting properties for low-cost applications, like high differential gain and high T/sub 0/. Another key aspect of the performance is the behavior of the GaInNAs-GaAs based lasers under high bit rate direct modulation. Here, we demonstrate the dynamic capabilities of GaInNAs-GaAs three-quantum-well ridge structure through 2.5-Gb/s directly modulated laser emission and transmission on standard fiber, in the temperature range 25/spl deg/C-85/spl deg/C. Besides transmission is demonstrated up to 10 Gb/s at 25/spl deg/C on the same fiber, without penalty and bit-error-rate floor. 相似文献
959.
Manesh K.M. Gopalan A.I. Kwang-Pill Lee Santhosh P. Kap-Duk Song Duk-Dong Lee 《Nanotechnology, IEEE Transactions on》2007,6(5):513-518
A nanofibrous sensor for ammonia gas is fabricated by electrospinning the composite of poly(diphenylamine) (PDPA) with poly(methyl methacrylate) (PMMA) onto the patterned interdigit electrode. The composite electrospun membrane shows interconnected fibrous morphology. Functional groups in PDPA and the high active surface area of the fibrous membrane make the device detect a lower concentration of ammonia with a good reproducibility. The sensing capability of the device is studied by monitoring the changes in resistance of the membrane with different concentrations of ammonia. The changes in resistance of the membrane shows linearity with the concentration of ammonia in the limit of 10 and 300 ppm. UV-visible spectroscopy reveals the mechanism of sensing ammonia by the membrane. 相似文献
960.
For computer designers, understanding the characteristics of workloads running on current and future computer systems is of utmost importance during microprocessor design a microarchitecture-independent method ensures an accurate characterization of inherent program behavior and avoids the weaknesses of microarchitecture-dependent metrics. 相似文献