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71.
Comments on the article by V. Murphy-Berman and V. Weisz (1996) in which some of the significant challenges and issues in implementing the United Nations Convention on the Rights of the Child (CRC) are discussed. The author believes that though the article was insightful, it overlooked the impact of armed conflict, one of the most profound sources of abuse of children's human rights worldwide. Some of the points made in an article by G. Machel (1996) are restated including the number of children soldiers and the physical, emotional, and psychological abuse they endure. The author goes on to mention other issues including parentless refugees, the dangers of land mines during and after the war, and the effects of sanctions on children. The author believes that intercultural differences and political issues may also hamper the implementation of the CRC. The article concludes with ways in which psychologists can help and the need to ratify the CRC. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A numerical study on a non-linear hyperbolic diffusion equation is proposed. The Hartree hybrid method combining finite difference techniques with the method of characteristics is used in the presence of discontinuities between initial and boundary conditions. The technique proved to be an useful tool to overcome oscillation problems and spurious solutions in case of strong non-linearities related to both attractive or repulsive interactions between diffusing species. Two different expressions for the diffusion coefficient are used in order to compare our results with the ones obtained in previous studies relying upon the Laplace transform technique and the MacCormack predictor–corrector method. Finally, an analytic approach based on the singular surface theory is proposed to motivate the numerical results and to clarify some controversial aspects concerning the penetration depth of a diffusive front in the presence of interactions.  相似文献   
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This paper addresses the problem of path following in two‐dimensional space for underactuated unmanned surface vehicles (USVs), defining a set of guidance laws at the kinematic level. The proposed nonlinear Lyapunov‐based control law yields convergence of the path‐following error coordinates to zero. Furthermore, the introduction of a virtual controlled degree of freedom for the target to be followed on the path removes singularity behaviors present in other guidance algorithms proposed in the literature. Some heuristic approaches are then proposed to face the problem of speed of advance adaptation based on path curvature measurement and steering action prediction. Finally a set of experimental results of all the proposed guidance laws, carried out with the Charlie USV, demonstrates the feasibility of the proposed approach and the performance improvements, in terms of precision in following the reference path and transient reduction, obtained by introducing speed adaptation heuristics. © 2009 Wiley Periodicals, Inc.  相似文献   
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The Association for Professionals in Infection Control and Epidemiology, Inc (APIC), is a multidisciplinary, voluntary, international organization of professionals who practice infection control and the application of epidemiology in all health settings. APIC is an international leader in prevention and control of infection transmission.  相似文献   
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