46,616 research outputs found

    Securing dynamic itineraries for mobile agent applications

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    In this paper we present a novel mechanism for the protection of dynamic itineraries for mobile agent applications. Itineraries that are decided as the agent goes are essential in complex applications based on mobile agents, but no approach has been presented until now to protect them. We have conceived a cryptographic scheme for shielding dynamic itineraries from tampering, impersonation and disclosure. By using trust strategically, our scheme provides a balanced trade-off between flexibility and security. Our protection scheme has been thought always bearing in mind a feasible implementation, and thus facilitates the development of applications that make use of it. An example application based on a real healthcare scenario is also presented to show its operation

    Towards Run-Time Verification of Compositions in the Web of Things using Complex Event Processing

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    Following the vision of the Internet of Things, physical world entities are integrated into virtual world things. Things are expected to become active participants in business and social processes. Then, the Internet of Things could benefit from the Web Service architecture like today’s Web does, so Future ser-vice-oriented Internet things will offer their functionality via service-enabled in-terfaces. In previous work, we demonstrated the need of considering the behav-iour of things to develop applications in a more rigorous way, and we proposed a lightweight model for representing such behaviour. Our methodology relies on the service-oriented paradigm and extends the DPWS profile to specify the order with which things can receive messages. We also proposed a static verifi-cation technique to check whether a mashup of things respects the behaviour, specified at design-time, of the composed things. However, a change in the be-haviour of a thing may cause that some compositions do not fulfill its behaviour anymore. Moreover, given that a thing can receive requests from instances of different mashups at run-time, these requests could violate the behaviour of that thing, even though each mashup fulfills such behaviour, due to the change of state of the thing. To address these issues, we present a proposal based on me-diation techniques and complex event processing to detect and inhibit invalid invocations, so things only receive requests compatible with their behaviour.Work partially supported by projects TIN2008-05932, TIN2012-35669, CSD2007-0004 funded by Spanish Ministry MINECO and FEDER; P11-TIC-7659 funded by Andalusian Government; and Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tec

    ADAM: Analysis of Discrete Models of Biological Systems Using Computer Algebra

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    Background: Many biological systems are modeled qualitatively with discrete models, such as probabilistic Boolean networks, logical models, Petri nets, and agent-based models, with the goal to gain a better understanding of the system. The computational complexity to analyze the complete dynamics of these models grows exponentially in the number of variables, which impedes working with complex models. Although there exist sophisticated algorithms to determine the dynamics of discrete models, their implementations usually require labor-intensive formatting of the model formulation, and they are oftentimes not accessible to users without programming skills. Efficient analysis methods are needed that are accessible to modelers and easy to use. Method: By converting discrete models into algebraic models, tools from computational algebra can be used to analyze their dynamics. Specifically, we propose a method to identify attractors of a discrete model that is equivalent to solving a system of polynomial equations, a long-studied problem in computer algebra. Results: A method for efficiently identifying attractors, and the web-based tool Analysis of Dynamic Algebraic Models (ADAM), which provides this and other analysis methods for discrete models. ADAM converts several discrete model types automatically into polynomial dynamical systems and analyzes their dynamics using tools from computer algebra. Based on extensive experimentation with both discrete models arising in systems biology and randomly generated networks, we found that the algebraic algorithms presented in this manuscript are fast for systems with the structure maintained by most biological systems, namely sparseness, i.e., while the number of nodes in a biological network may be quite large, each node is affected only by a small number of other nodes, and robustness, i.e., small number of attractors

    Genetic Programming for Smart Phone Personalisation

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    Personalisation in smart phones requires adaptability to dynamic context based on user mobility, application usage and sensor inputs. Current personalisation approaches, which rely on static logic that is developed a priori, do not provide sufficient adaptability to dynamic and unexpected context. This paper proposes genetic programming (GP), which can evolve program logic in realtime, as an online learning method to deal with the highly dynamic context in smart phone personalisation. We introduce the concept of collaborative smart phone personalisation through the GP Island Model, in order to exploit shared context among co-located phone users and reduce convergence time. We implement these concepts on real smartphones to demonstrate the capability of personalisation through GP and to explore the benefits of the Island Model. Our empirical evaluations on two example applications confirm that the Island Model can reduce convergence time by up to two-thirds over standalone GP personalisation.Comment: 43 pages, 11 figure

    Managing Knowledge as Business Rules

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    In today’s business environment, it is a certainty that will manage to survive especially those organizations which are striving to adapt quickly and with low costs to the new demands of market competition. Knowledge represented by internal business rules of an organization can help crystallize their orientation in order to ensure a competitive advantage in the market. In this context and in a relatively short time, a new trend in software development has arisen, ex-tending current methods and putting a strong emphasis on business rules. This article outlines the importance of managing business rules in an organized manner using dedicated software products and furthermore presents a general prototype for a business rules repository.Business Rules, Management, Knowledge, Rule Engine, Repository Prototype

    A heuristic-based approach to code-smell detection

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    Encapsulation and data hiding are central tenets of the object oriented paradigm. Deciding what data and behaviour to form into a class and where to draw the line between its public and private details can make the difference between a class that is an understandable, flexible and reusable abstraction and one which is not. This decision is a difficult one and may easily result in poor encapsulation which can then have serious implications for a number of system qualities. It is often hard to identify such encapsulation problems within large software systems until they cause a maintenance problem (which is usually too late) and attempting to perform such analysis manually can also be tedious and error prone. Two of the common encapsulation problems that can arise as a consequence of this decomposition process are data classes and god classes. Typically, these two problems occur together – data classes are lacking in functionality that has typically been sucked into an over-complicated and domineering god class. This paper describes the architecture of a tool which automatically detects data and god classes that has been developed as a plug-in for the Eclipse IDE. The technique has been evaluated in a controlled study on two large open source systems which compare the tool results to similar work by Marinescu, who employs a metrics-based approach to detecting such features. The study provides some valuable insights into the strengths and weaknesses of the two approache
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