A Systematic Mapping on the Role-Permission Relationship in Role Based Access Control Models

Access control is a key component of security in any computer system. In the last two decades, the research on Role Basead Access Control Models was intense. One of the most important components of a Role Based Model is the Role-Permission Relationship. In this paper, the technique of systematic mapping is used to identify, extract and analyze many approaches applied to establish the Role-Permission Relationship. The main goal of this mapping is pointing directions of significant research in the area of Role Based Access Control Models.

Cross-national differences in questionnaires do not necessarily reflect comparable differences in disorder prevalence

To examine whether the widely used Strengths and Difficulties Questionnaire (SDQ) can validly be used to compare the prevalence of child mental health problems cross nationally. We used data on 29,225 5- to 16-year olds in eight population-based studies from seven countries: Bangladesh, Brazil, Britain, India, Norway, Russia and Yemen. Parents completed the SDQ in all eight studies, teachers in seven studies and youth in five studies. We used these SDQ data to calculate three different sorts of "caseness indicators" based on (1) SDQ symptoms, (2) SDQ symptoms plus impact and (3) an overall respondent judgement of 'definite' or 'severe' difficulties. Respondents also completed structured diagnostic interviews including extensive open-ended questions (the Development and Well-Being Assessment, DAWBA). Diagnostic ratings were all carried out or supervised by the DAWBA's creator, working in conjunction with experienced local professionals. As judged by the DAWBA, the prevalence of any mental disorder ranged from 2.2% in India to 17.1% in Russia. The nine SDQ caseness indicators (three indicators times three informants) explained 8-56% of the cross-national variation in disorder prevalence. This was insufficient to make meaningful prevalence estimates since populations with a similar measured prevalence of disorder on the DAWBA showed large variations across the various SDQ caseness indicators. The relationship between SDQ caseness indicators and disorder rates varies substantially between populations: cross-national differences in SDQ indicators do not necessarily reflect comparable differences in disorder rates. More generally, considerable caution is required when interpreting cross-cultural comparisons of mental health, particularly when these rely on brief questionnaires.

A quantitative analysis of current security concerns and solutions for cloud computing

The development of cloud computing services is speeding up the rate in which the organizations outsource their computational services or sell their idle computational resources. Even though migrating to the cloud remains a tempting trend from a financial perspective, there are several other aspects that must be taken into account by companies before they decide to do so. One of the most important aspect refers to security: while some cloud computing security issues are inherited from the solutions adopted to create such services, many new security questions that are particular to these solutions also arise, including those related to how the services are organized and which kind of service/data can be placed in the cloud. Aiming to give a better understanding of this complex scenario, in this article we identify and classify the main security concerns and solutions in cloud computing, and propose a taxonomy of security in cloud computing, giving an overview of the current status of security in this emerging technology.

Preserve and protect in a science museum

Reflections on the university campus usually focus on its relevancy as a research and teaching area; however, the need for preservation, protection, maintenance and cleaning only become visible in the event of inadequacy or lack thereof. The aim of this study is to address the characteristics of the preservation and security measures performed at the Science and Technology Park of the University of São Paulo (Parque de Ciência e Tecnologia da Universidade de São Paulo), agency subjected to the Dean’s Office for Culture and University Extension (Pró-Reitoria de Cultura e Extensão Universitária). Because of its history and location, the Park requires special care. The Park’s land formerly housed the Astronomical Observatory of São Paulo and the Institute of Astronomy and Geophysics of the University of São Paulo (Instituto de Astronomia e Geofísica – IAG-USP), within the Fontes do Ipiranga State Park (Parque Estadual das Fontes do Ipiranga – PEFI), in the city of São Paulo. Preservation and reconversion activities relative to historical buildings are developed at the Park. The institution’s location and its specificities require security in its borders, as well as in relation to the users of the park.

Architectures, stability and optimization for clock distribution networks

Synchronous telecommunication networks, distributed control systems and integrated circuits have its accuracy of operation dependent on the existence of a reliable time basis signal extracted from the line data stream and acquirable to each node. In this sense, the existence of a sub-network (inside the main network) dedicated to the distribution of the clock signals is crucially important. There are different solutions for the architecture of the time distribution sub-network and choosing one of them depends on cost, precision, reliability and operational security. In this work we expose: (i) the possible time distribution networks and their usual topologies and arrangements. (ii) How parameters of the network nodes can affect the reachability and stability of the synchronous state of a network. (iii) Optimizations methods for synchronous networks which can provide low cost architectures with operational precision, reliability and security. (C) 2011 Elsevier B. V. All rights reserved.

Segurança alimentar em domicílios chefiados por idosos, Brasil

A segurança alimentar nos domicílios chefiados por idosos tem uma dimensão especial no que se refere às condições de saúde e bem-estar, uma vez que parece evidente a importância de garantir a este contingente populacional a possibilidade de continuar a contribuir na sociedade de forma ativa e produtiva. OBJETIVO: Determinar a prevalência de insegurança alimentar em domicílios cujos chefes são idosos, segundo características sociodemográficas. MÉTODOS: Trata-se de estudo descritivo com domicílios cujos chefes têm 60 anos ou mais de idade declarada, selecionados da Pesquisa Nacional de Amostra de Domicílios - PNAD 2004. Empregou-se a Escala Brasileira de Insegurança Alimentar, classificando-se os domicílios em segurança alimentar e insegurança alimentar leve, moderada e grave. A análise descritiva dos dados incluiu a distribuição de frequência dos domicílios de acordo com os níveis de insegurança alimentar nos estratos das variáveis sociodemográficas, levando-se em consideração o efeito do desenho. RESULTADOS: O estudo mostrou que 29,8% dos domicílios se encontravam na condição de insegurança alimentar e que tal condição estava significativamente associada com regiões menos abastadas (Norte/Nordeste, rural), com os segmentos populacionais mais desfavorecidos (mais pobres e menos escolarizados) e, ainda com características de gênero (mulheres) e raciais (indígenas, pardos e pretos) as quais sabidamente ocupam os níveis inferiores da hierarquia social. CONCLUSÃO: A distribuição da insegurança alimentar em domicílios chefiados por idosos segue tendência similar dos domicílios brasileiros, ratificando a maior prevalência desta condição nos estratos socioeconômicos mais desfavorecidos da população ou entre características associadas à pobreza.