11,955 research outputs found

    The Refugee Problem: An International Legal Tangle

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    Change is constant and computing paradigm is no exception. It has witnessed major shifts right from centralized client server systems to widely distributed systems. This time the locus of change in the computing paradigm is moving towards virtualization, paving way to cloud computing. Cloud computing aims at providing computing services to its users as an utility. It allows its authenticated users to access a wide range of highly scalable computing capabilities and services via the internet on a pay-per-usage basis. Organisations not only view these benefits as cost-saving strategies, but also aim at improving the competitive advantages using cloud computing. Hence, this has given rise to a new horizon in IT/IS outsourcing. With a collaboration of cloud computing and outsourcing emerged a new concept called cloudsourcing. Cloudsourcing can be termed as the next generation outsourcing and the next phase of cloud computing promising benefits from both the areas. Cloudsourcing is outsourcing traditional business via the cloud infrastructure. Though there is pompous popularity surrounding this new technology, there is much hesitation in adopting it due to the inherent security issues. This paper discusses in detail the security issues and possible solution to the same. As this is a new concept, not much work is identified to be done in providing a set of guidelines to adopt cloudsourcing that are very specific to information security. This work intends to fill this aperture by building a set of well-defined information security guidelines, which can be termed as a novel. For this purpose, design science research method proposed by Hevner et al is used so as to accomplish this goal. Initially, a literature study is done after which an exploratory study comprising of interviews is done to gather qualitative data. The results of the exploratory interview is tested for correctness and evaluated based on an evaluation study comprising a survey based questionnaire. The analysis of the evaluation study results provides the final results. In such an attempt, the identified countermeasures to risks are classified into three groups namely, organisational, technical and regulatory and compliance guidelines. Hence the end results constituting the set of information security guidelines are classified into the above mentioned groups. This work is assumed to contribute to our understanding of information security in cloudsourcing and in supporting IT decision makers, IT project managers and security executives of organisations for a smooth and secure transition towards cloudsourcing their business

    Summary of Workshop to Review an OMB Report on Regulatory Risk Assessment and Management

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    Summary of the results of an invitational workshop conducted to peer review the 1990 OMB report, CURRENT REGULATORY ISSUES IN Risk ASSESSMENT AND Risk MANAGENMENTIN REGULATORY PROGRAM OF THE UNITED STATES GOVERNMENT, APRIL 1, 1990 - MARCH 31, 1991

    Model Based Mission Assurance: NASA's Assurance Future

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    Model Based Systems Engineering (MBSE) is seeing increased application in planning and design of NASAs missions. This suggests the question: what will be the corresponding practice of Model Based Mission Assurance (MBMA)? Contemporaneously, NASAs Office of Safety and Mission Assurance (OSMA) is evaluating a new objectives based approach to standards to ensure that the Safety and Mission Assurance disciplines and programs are addressing the challenges of NASAs changing missions, acquisition and engineering practices, and technology. MBSE is a prominent example of a changing engineering practice. We use NASAs objectives-based strategy for Reliability and Maintainability as a means to examine how MBSE will affect assurance. We surveyed MBSE literature to look specifically for these affects, and find a variety of them discussed (some are anticipated, some are reported from applications to date). Predominantly these apply to the early stages of design, although there are also extrapolations of how MBSE practices will have benefits for testing phases. As the effort to develop MBMA continues, it will need to clearly and unambiguously establish the roles of uncertainty and risk in the system model. This will enable a variety of uncertainty-based analyses to be performed much more rapidly than ever before and has the promise to increase the integration of CRM (Continuous Risk Management) and PRA (Probabilistic Risk Analyses) even more fully into the project development life cycle. Various views and viewpoints will be required for assurance disciplines, and an over-arching viewpoint will then be able to more completely characterize the state of the project/program as well as (possibly) enabling the safety case approach for overall risk awareness and communication

    Observation of Infrared and Radio Lines of Molecules toward GL2591 and Comparison to Physical and Chemical Models

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    We have observed rovibrational transitions of acetylene and HCN near 13 microns in absorption toward GL2591. We also observed rotational lines of CS, HCN, H2CO, and HCO+. The combined data are analyzed in terms of models with a cloud envelope with density gradients and discrete regions of hot, dense gas, probably near the infrared source. The abundance of HCN is enhanced by a factor of 400 in the gas producing the infrared absorption, in agreement with chemical models which involve depletion of molecules onto grains and subsequent sublimation when temperatures are raised.Comment: 34 pages, postscript with 14 postscript figure files, uuencoded compressed and tar'ed; unpacks self with csh. In case of problems, contact [email protected]

    Epibenthic and benthic microcrustaceans (copepods, cladocerans, ostracods) from a nearshore area in southeastern Lake Michigan

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110059/1/lno19772261059.pd

    Optimal and Distributed Protocols for Cross-Layer Design of Physical & Transport Layers in MANETs

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    We seek distributed protocols that attain the global optimum allocation of link transmitter powers and source rates in a cross-layer design of a mobile ad-hoc network. Although the underlying network utility maximization is nonconvex, convexity plays a major role in our development. We provide new convexity results surrounding the Shannon capacity formula, allowing us to abandon suboptimal high-SIR approximations that have almost become entrenched in the literature. More broadly, these new results can be back-substituted into many existing problems for similar benefit. Three protocols are developed. The first is based on a convexification of the underlying problem, relying heavily on our new convexity results. We provide conditions under which it produces a globally optimum resource allocation. We show how it may be distributed through message passing for both rate- and power-allocation. Our second protocol relaxes this requirement and involves a novel sequence of convex approximations, each exploiting existing TCP protocols for source rate allocation. Message passing is only used for power control. Our convexity results again provide sufficient conditions for global optimality. Our last protocol, motivated by a desire of power control devoid of message passing, is a near optimal scheme that makes use of noise measurements and enjoys a convergence rate that is orders of magnitude faster than existing methods

    Optimal Power Control for Rayleigh-Faded Multiuser Systems With Outage Constraints

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    How can we achieve the conflicting goals of reduced transmission power and increased capacity in a wireless network, without attempting to follow the instantaneous state of a fading channel? In this paper, we address this problem by jointly considering power control and multiuser detection (MUD) with outage-probability constraints in a Rayleigh fast-fading environment. The resulting power-control algorithms (PCAs) utilize the statistics of the channel and operate on a much slower timescale than traditional schemes. We propose an optimal iterative solution that is conceptually simple and finds the minimum sum power of all users while meeting their outage targets. Using a derived bound on outage probability, we introduce a mapping from outage to average signal-to-interference ratio (SIR) constraints. This allows us to propose a suboptimal iterative scheme that is a variation of an existing solution to a joint power control and MUD problem involving SIR constraints. We further use a recent result that transforms complex SIR expressions into a compact and decoupled form, to develop a noniterative and computationally inexpensive PCA for large systems of users. Simulation results are presented showing the closeness of the optimal and mapped schemes, speed of convergence, and performance comparisons

    Enabling Assurance in the MBSE Environment

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    A number of specific benefits that fit within the hallmarks of effective development are realized with implementation of model-based approaches to systems and assurance. Model Based Systems Engineering (MBSE) enabled by standardized modeling languages (e.g., SysML) is at the core. These benefits in the context of spaceflight system challenges can include: Improved management of complex development, Reduced risk in the development process, Improved cost management, Improved design decisions. With appropriate modeling techniques the assurance community can improve early oversight and insight into project development. NASA has shown the basic constructs of SysML in an MBSE environment offer several key advantages, within a Model Based Mission Assurance (MBMA) initiative
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