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81.
Irene Ramos-Vielba Manuel Fernández-Esquinas Elena Espinosa-de-los-Monteros 《Scientometrics》2010,84(3):649-667
Studies of university–industry collaboration remain subject to important limitations due to the shortage of empirical data
and a lack of consistency in that obtained to date. This article puts into practice a set of universities Third Mission indicators
in a regional innovation system. Selected indicators previously compiled from literature were reorganized and pre-tested.
We have undertaken two face-to-face surveys of 737 firms and 765 heads of research teams, respectively. The results test the
validation of indicators and provide a complex map of university–industry linkages as well as some observations on the flexibility
needed to address this issue. 相似文献
82.
A rejoinder to "Psychotherapy research ethics: Continuing the debate on controlled clinical trials."
Imber Stanley D.; Glanz Lawrence M.; Elkin Irene; Sotsky Stuart M.; Boyer Jenny L.; Leber William R. 《Canadian Metallurgical Quarterly》1987,42(12):1132
Responds to C. A. Heflinger's (1987) critique of the present authors (1986) by reiterating their concern for the principle of autonomy. The present authors note that all patients were fully informed about the research plan and their right to withdraw. Nonetheless, the ethical criticism offered by Heflinger regarding randomization cannot be entirely dismissed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
84.
Hall Gordon C. Nagayama; Bansal Anita; Lopez Irene R. 《Canadian Metallurgical Quarterly》1999,11(2):186
Meta-analyses were performed on 25 comparative Minnesota Multiphasic Personality Inventory (MMPI) and MMPI-2 studies of 1,428 male African Americans versus 2,837 male European Americans, 12 studies of 1,053 female African Americans versus 1,470 female European Americans, and 13 studies of 500 male Latino Americans and 1,345 male European Americans. Aggregate effect sizes suggest higher scores for ethnic minority groups than for European Americans on some MMPI/MMPI-2 scales and lower scores on others. However, none of the aggregate effect sizes suggest substantive differences from either a statistical or clinical perspective. The MMPI and MMPI-2 apparently do not unfairly portray African Americans and Latinos as pathological. Effect sizes across studies generally did not vary as a function of sociodemographic variables, research setting, or use of the MMPI versus MMPI-2. It is recommended that additional between- and within-ethnic groups psychopathology research continue. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
ABSTRACT A mathematical model of simultaneous mass, heat and momentum transfer for two-phase flow of a gas and a solid/liquid slurry was developed. The model was applied to calculation of the drying process of coal-water slurry droplets in a gas medium in a steady one-dimensional flow. The model was based on the well-known two-stage drying process for slurry droplets. After the first period of drying, in which the evaporation rate is controlled by the gas phase resistance, the evaporating liquid diffuses through the porous shell (crust) and then, by convection, into the gas medium. Inside the dry external crust of the drop, a wet central core forms, which shrinks as evaporation proceeds. The temperature of the slurry droplet rises. The process ends when the temperature of the dry outer crust reaches the coal ignition temperature in the case of combustion or when the moisture of the particle reaches the final required moisture. The developed model was based on one-dimensional balance equations of mass, energy and momentum for the liquid/solid and gas phases. The system of governing equations was represented by first-order differential equations and solved simultaneously. The numerical solution of the governing equations was obtained using Gear's method. The model permitted calculation 相似文献
86.
In this paper we consider Runge–Kutta discontinuous Galerkin (RKDG) schemes for Vlasov–Poisson systems that model collisionless plasmas. One-dimensional systems are emphasized. The RKDG method, originally devised to solve conservation laws, is seen to have excellent conservation properties, be readily designed for arbitrary order of accuracy, and capable of being used with a positivity-preserving limiter that guarantees positivity of the distribution functions. The RKDG solver for the Vlasov equation is the main focus, while the electric field is obtained through the classical representation by Green’s function for the Poisson equation. A rigorous study of recurrence of the DG methods is presented by Fourier analysis, and the impact of different polynomial spaces and the positivity-preserving limiters on the quality of the solutions is ascertained. Several benchmark test problems, such as Landau damping, the two-stream instability, and the Kinetic Electro static Electron Nonlinear wave, are given. 相似文献
87.
Interfaces between two dissimilar metals have been observed to exhibit a range of atomic structures, from atomically flat to atomically stepped. Using atomic-scale simulation and theory, we study the influence of the intrinsic bimetal interface structure on the nucleation of lattice dislocations. Interface structure is found to have a strong effect on which dislocations are nucleated and the type of nucleation site. We develop a theoretical model that provides criteria for predicting these effects based on key structural relationships between the interface and adjoining crystals. In recognition of these critical conditions, we construct a map that identifies the most likely nucleation site from a given interface. The theory and map developed here can guide efforts to tune interface structures for controlling the strength and deformation of heterogeneous materials. 相似文献
88.
89.
Brian D. Garland Irene J. Beyerlein Linda S. Schadler 《Composites Science and Technology》2001,61(16):4209-2480
Recent experimental work (Narayanan S, Schadler LS. Mechanisms of kink band formation in graphite/epoxy compsites: a micromechanical experimental study. Comp Sci Technol 1999; 59:2201-13) suggests that kink bands in unidirectional continuous carbon fiber reinforced polymer composites initiate from damage zones formed under axial compressive loads. A damage zone consists of a cluster of locally crushed fibers and broken fibers, that are often fractured at an angle, θ > 0°, normal to the fiber axis. Typically, under compressive loads, fiber breaks in damage zones form roughly along a plane at an angle φ, normal to the fiber axis. These damage zones produce stress concentrations which can lead to instabilities in the nearby fiber and matrix and initiate microbuckling and kink bands. This paper extends a micromechanical influence function technique based on earlier shear lag fiber composite models. Our modified technique calculates the fiber axial and matrix shear stress concentrations due to multiple angled and crushed fibers in arbitrary configurations. Modeling reveals that angled or ‘shear’ breaks (θ > 0°) can lead to higher shear stress concentrations in the matrix than transverse breaks (θ=0°). Also we find that the damage zone is more likely to form at an angle φ, which is greater than that of its individual fiber breaks, θ. When φ is slightly greater than θ, the shear stress in the surrounding matrix regions within the damage zone achieves a maximum, potentially weakening the matrix and interface and consequently leading to kink band formation. Monte Carlo simulations incorporating this stress analysis predict that the initiation and propagation of crushed and angled breaks progress roughly along an angle, φ ≈ 17° in a linear elastic system. When possible, our model results are compared to strain measurements of fiber composites under compression obtained by Narayanan and Schadler using micro-Raman spectroscopy (MRS). 相似文献
90.
A brief history of empirical research on violence in close relationships is presented. Assumptions of and conclusions made by feminist researchers about the problems of battered wives are reviewed. It is argued that their focus on marital violence as a form of aggression against women by men and their concern for severely beaten wives may have caused them to ignore high levels of female violence in marriage and dating. J. Archer's (see record 2000-15524-001) meta-analysis of studies of marital and dating violence showed that both sexes display violence in these relationships, although women are more likely to be injured. An expansion of Archer's definition of heterosexual violence (or violence in close relationships) to include sexual aggression and stalking is suggested. Reasons for relatively high levels of female violence in close relationships relative to violence toward strangers are briefly discussed. It is argued that more attention needs to be given to male victims of violence from their partners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献