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91.
M Choquet JM Darves-Bornoz S Ledoux R Manfredi C Hassler 《Canadian Metallurgical Quarterly》1997,21(9):823-832
OBJECTIVES: To measure the prevalence rate of rape among French adolescents; to analyze the associated health and behavioral problems; to analyze the use of the health care system by rape victims. METHOD: A national representative sample of 8,140 students attending public secondary schools in France (grades 8 to 12) filled in a self-administered questionnaire (274 questions) on health and behavior problems (acceptance rate = 87%). Each rape victim in the sample (n = 61) was matched to two nonvictims (n = 122). RESULTS: The reported prevalence rate of rape was .8% (.9% among girls, .6% among boys). For both boys and girls, there was a relationship between rape and current sleep difficulties, depressive symptoms, somatic complaints, tobacco consumption, and behavior problems (running away, violent behavior, stealing, and school absenteeism). Additional problems were associated for boy rape victims: attempted suicide, regular use of alcohol and of illicit drugs. Rape victims did consult health professionals, but the majority saw neither a mental health specialist nor a social worker. CONCLUSION: The findings indicate that rape victims, especially boys, have more behavior problems and health problems than nonrape victims. Authors suggest that adolescents who have ran away from home, attempted suicide, or manifested violent behavior should be systematically asked about rape. 相似文献
92.
Comparison of the imaging characteristics of curved-channel and straight-channel microchannel plates
We have measured and compared the spatial fidelity of two types of microchannel plates over roughly half of their active area. Measurements of the spatial fidelity of curved-channel microchannel plates confirm earlier reports of large (>25 mum), irregular position offsets between the front and the back of the microchannel plates. Straight-pore microchannel plates used in a chevron configuration, on the other hand, showed almost no such position offsets (<4 mum). 相似文献
93.
Manoj?Thomas Daniela?Costa Tiago?OliveiraEmail author 《Information Systems Frontiers》2016,18(4):693-710
Green Information Technology (IT) tools and practices contribute to environmental sustainability and business processes virtualization. To assess whether IT-enabled process virtualization capabilities impact organizational Green IT initiatives, Bose and Luo 2011 proposed a conceptual model that combines three theories: technology-organization-environment framework, process virtualization theory, and diffusion of innovation theory. We conducted an empirical analysis of data from 251 European firms, and found that environment context (competition intensity and regulatory support) was more important to Green IT initiatives than organization or technology context. Technology factors (sensory readiness, relationship readiness, synchronism readiness, and identification and control readiness) facilitating process virtualization were not found significant to organizational Green IT initiatives. 相似文献
94.
Thermophysical properties of different olive oils: Evaluating density and rheology through a fluid dynamic approach
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95.
Luis F. Silva Luiz F. Scheidegger Tiago Etiene João L. D. Comba Luis G. Nonato Cláudio T. Silva 《Computer Graphics Forum》2014,33(6):18-30
Simplicial meshes are useful as discrete approximations of continuous spaces in numerical simulations. In some applications, however, meshes need to be modified over time. Mesh update operations are often expensive and brittle, making the simulations unstable. In this paper we propose a framework for updating simplicial meshes that undergo geometric and topological changes. Instead of explicitly maintaining connectivity information, we keep a collection of weights associated with mesh vertices, using a Weighted Delaunay Triangulation (WDT). These weights implicitly define mesh connectivity and allow direct merging of triangulations. We propose two formulations for computing the weights, and two techniques for merging triangulations, and finally illustrate our results with examples in two and three dimensions. 相似文献
96.
In order to provide oils light in color and free of objectionable odor, it is generally necessary to process them with various
adsorbents such as fuller’s earth, activated clay, and activated carbon. While this treatment furnishes a more desirable product
in keeping with the taste of the American public, unfortunately, it some-times results in leaving the oil more susceptible
to the development of rancidity later on. This work is a study of the effect of various adsorbents, and while it does not
provide any final conclusions, it does indicate that the resulting rancidity can be controlled to a large extent by the selection
of the proper adsorbent.
This paper was presented at the Symposium on the Chemistry & Metabolism of Fats, held at the Rochester meeting of the American
Chemical Society. It is published here by special arrangement with the Division of Agricultural & Food Chemistry. 相似文献
97.
The control of uncertain nonlinear systems by high‐gain observer based output feedback is addressed. Two tracking sliding mode controllers are designed for a broad class of uncertain nonlinear systems with arbitrary relative degree and unmatched polynomial nonlinearities in the unmeasured states. The proposed strategies are based either on dwell‐time for control activation or on simple norm state observers to remove the peaking phenomenon related with high‐gain observers, depending on the nonlinearity growth conditions. In contrast with previous works, exact tracking is also achieved by means of a switching strategy based on locally exact differentiators. Global or semi‐global stability is proved by using Lyapunov theory and on small‐gain analysis. Simulations show that the proposed methodologies provide better and uniform transient behavior, larger regions of attraction, performance recovery with significantly smaller observer gains and good robustness properties with respect to exogenous disturbances and measurement noise. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
98.
This paper deals with the design of a network-on-chip reconfigurable pseudorandom number generation unit that can map and execute meta-heuristic algorithms in hardware. The unit can be configured to implement one of the following five linear generator algorithms: a multiplicative congruential, a mixed congruential, a standard multiple recursive, a mixed multiple recursive, and a multiply-with-carry. The generation unit can be used both as a pseudorandom and a message passing-based server, which is able to produce pseudorandom numbers on demand, sending them to the network-on-chip blocks that originate the service request. The generator architecture has been mapped to a field programmable gate array, and showed that millions of numbers in 32-, 64-, 96-, or 128-bit formats can be produced in tens of milliseconds. 相似文献
99.
Model predictive control (MPC) has become one of the most popular control techniques in the process industry mainly because of its ability to deal with multiple-input–multiple-output plants and with constraints. However, in the presence of model uncertainties and disturbances its performance can deteriorate. Therefore, the development of robust MPC techniques has been widely discussed during the last years, but they were rarely, if at all, applied in practice due to the conservativeness or the computational complexity of the approaches. In this paper, we present multi-stage NMPC as a promising robust non-conservative nonlinear model predictive control scheme. The approach is based on the representation of the evolution of the uncertainty by a scenario tree, and leads to a non-conservative robust control of the uncertain plant because the adaptation of future inputs to new information is taken into account. Simulation results show that multi-stage NMPC outperforms standard and min–max NMPC under the presence of uncertainties for a semi-batch polymerization benchmark problem. In addition, the advantages of the approach are illustrated for the case where only noisy measurements are available and the unmeasured states and the uncertainties have to be estimated using an observer. It is shown that better performance can be achieved than by estimating the unknown parameters online and adapting the plant model. 相似文献
100.
Evaluation of gaseous allyl isothiocyanate against the growth of mycotoxigenic fungi and mycotoxin production in corn stored for 6 months
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