1,453 research outputs found

    A Survey Of Drug Abuse In A Selected Junior High School

    Get PDF
    INTRODUCTION Over the past several years, public concern has greatly increased over mind-altering drug use among students. That concern has been evoked by a flow of reports from individuals, mass media, the police, and other governmental agencies, educators, and the community. The reports are consistent in telling of a remarkable expansion of student interest in and use of drugs which are illicit or exotic. Drug abuse is an issue that concerns all levels of society, from the very low socio-economic groups to the extreme high socio-economic groups. The potential drug abusers range from the submissive poor to the successful affluent groups of individuals. The problem of drug abuse in our nation is rising at such an alarming rate, which warrants the condition that if we are to survive as a society that is not hampered by the frills and thrills of addicts, it is imperative that we find a workable solution. Currently, preventative and rehabilitative efforts are being made to combat the problem of drug abuse. There are controversial views as to the cause of drug abuse, which consequently make drug abuse a difficult problem for rehabilitation. Rehabilitation or the road back (as it is often called) is a puzzling task. A recent review of rehabilitation approaches to drug abuse stated: No one knows whether the goals of treatment as set forth are realistic or even desirable. Since no one knows why people become narcotic addicts, no one knows either how to make them stop or what will happen if they do stop. Not all approaches to rehabilitation are the same; different people require somewhat different treatment. The method of treatment are unlike in nature as the individuals themselves. The task of getting people to stop abusing drugs is as complex as it is confusing. According to DeLong, there is no uniform theory of addiction and no adequate description of the addict population. Also, addiction has spread rapidly in recent years, and we know less about the new population than we do about the old, and we knew very little before

    How explicit are the barriers to failure in safety arguments?

    Get PDF
    Safety cases embody arguments that demonstrate how safety properties of a system are upheld. Such cases implicitly document the barriers that must exist between hazards and vulnerable components of a system. For safety certification, it is the analysis of these barriers that provide confidence in the safety of the system. The explicit representation of hazard barriers can provide additional insight for the design and evaluation of system safety. They can be identified in a hazard analysis to allow analysts to reflect on particular design choices. Barrier existence in a live system can be mapped to abstract barrier representations to provide both verification of barrier existence and a basis for quantitative measures between the predicted barrier behaviour and performance of the actual barrier. This paper explores the first stage of this process, the binding between explicit mitigation arguments in hazard analysis and the barrier concept. Examples from the domains of computer-assisted detection in mammography and free route airspace feasibility are examined and the implications for system certification are considered

    G(2) quivers

    Get PDF
    We present, in explicit matrix representation and a modernity befitting the community, the classification of the finite discrete subgroups of G2 and compute the McKay quivers arising therefrom. Of physical interest are the classes of Script N = 1 gauge theories descending from M-theory and of mathematical interest are possible steps toward a systematic study of crepant resolutions to smooth G2 manifolds as well as generalised McKay Correspondences. This writing is a companion monograph to hep-th/9811183 and hep-th/9905212, wherein the analogues for Calabi-Yau three- and four-folds were considered

    Engaging students with profound and multiple disabilities using humanoid robots

    Get PDF
    Engagement is the single best predictor of successful learning for children with intellectual disabilities yet achieving engagement with pupils who have profound or multiple disabilities (PMD) presents a challenge to educators. Robots have been used to engage children with autism but are they effective with pupils whose disabilities limit their ability to control other technology? Learning objectives were identified for eleven pupils with PMD and a humanoid robot was programmed to enable teachers to use it to help pupils achieve these objectives. These changes were evaluated with a series of eleven case studies where teacher-pupil dyads were observed during four planned video recorded sessions. Engagement was rated in a classroom setting and during the last session with the robot. Video recordings were analysed for duration of engagement and teacher assistance and number of goals achieved. Rated engagement was significantly higher with the robot than in the classroom. Observations of engagement, assistance and goal achievement remained at the same level throughout the sessions suggesting no reduction in the novelty factor

    Approximation Algorithms for the Capacitated Domination Problem

    Full text link
    We consider the {\em Capacitated Domination} problem, which models a service-requirement assignment scenario and is also a generalization of the well-known {\em Dominating Set} problem. In this problem, given a graph with three parameters defined on each vertex, namely cost, capacity, and demand, we want to find an assignment of demands to vertices of least cost such that the demand of each vertex is satisfied subject to the capacity constraint of each vertex providing the service. In terms of polynomial time approximations, we present logarithmic approximation algorithms with respect to different demand assignment models for this problem on general graphs, which also establishes the corresponding approximation results to the well-known approximations of the traditional {\em Dominating Set} problem. Together with our previous work, this closes the problem of generally approximating the optimal solution. On the other hand, from the perspective of parameterization, we prove that this problem is {\it W[1]}-hard when parameterized by a structure of the graph called treewidth. Based on this hardness result, we present exact fixed-parameter tractable algorithms when parameterized by treewidth and maximum capacity of the vertices. This algorithm is further extended to obtain pseudo-polynomial time approximation schemes for planar graphs

    Supergravity Duals for N=2 Gauge Theories

    Get PDF
    We construct supergravity solutions for Dp-branes at orbifold points. The solutions are written in terms of a single function, which is the solution to a nonlinear differential equation. The near horizon limits of these solutions are dual, in the AdS/CFT sense, to super-Yang-Mills theories with 8 supercharges in various dimensions. In particular, we present a dual to N=2 SU(N) SYM theory in 3+1 dimensions, and analyse some aspects of the duality.Comment: 15 pages, late

    Uniformly Accelerated Charge in a Quantum Field: From Radiation Reaction to Unruh Effect

    Full text link
    We present a stochastic theory for the nonequilibrium dynamics of charges moving in a quantum scalar field based on the worldline influence functional and the close-time-path (CTP or in-in) coarse-grained effective action method. We summarize (1) the steps leading to a derivation of a modified Abraham-Lorentz-Dirac equation whose solutions describe a causal semiclassical theory free of runaway solutions and without pre-acceleration patholigies, and (2) the transformation to a stochastic effective action which generates Abraham-Lorentz-Dirac-Langevin equations depicting the fluctuations of a particle's worldline around its semiclassical trajectory. We point out the misconceptions in trying to directly relate radiation reaction to vacuum fluctuations, and discuss how, in the framework that we have developed, an array of phenomena, from classical radiation and radiation reaction to the Unruh effect, are interrelated to each other as manifestations at the classical, stochastic and quantum levels. Using this method we give a derivation of the Unruh effect for the spacetime worldline coordinates of an accelerating charge. Our stochastic particle-field model, which was inspired by earlier work in cosmological backreaction, can be used as an analog to the black hole backreaction problem describing the stochastic dynamics of a black hole event horizon.Comment: Invited talk given by BLH at the International Assembly on Relativistic Dynamics (IARD), June 2004, Saas Fee, Switzerland. 19 pages, 1 figur

    Dibaryon Spectroscopy

    Full text link
    The AdS/CFT correspondence relates dibaryons in superconformal gauge theories to holomorphic curves in Kaehler-Einstein surfaces. The degree of the holomorphic curves is proportional to the gauge theory conformal dimension of the dibaryons. Moreover, the number of holomorphic curves should match, in an appropriately defined sense, the number of dibaryons. Using AdS/CFT backgrounds built from the generalized conifolds of Gubser, Shatashvili, and Nekrasov (1999), we show that the gauge theory prediction for the dimension of dibaryonic operators does indeed match the degree of the corresponding holomorphic curves. For AdS/CFT backgrounds built from cones over del Pezzo surfaces, we are able to match the degree of the curves to the conformal dimension of dibaryons for the n'th del Pezzo surface, n=1,2,...,6. Also, for the del Pezzos and the A_k type generalized conifolds, for the dibaryons of smallest conformal dimension, we are able to match the number of holomorphic curves with the number of possible dibaryon operators from gauge theory.Comment: 30 pages, 6 figures, corrected refs; v3 typos correcte
    • …
    corecore