SPIN is an efficient verification system for models of distributed software systems. It has been used to detect design errors in applications ranging from high-level descriptions of distributed algorithms to detailed code for controlling telephone exchanges. The paper gives an overview of the design and structure of the verifier, reviews its theoretical foundation, and gives an overview of significant practical applications.

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The model checker SPIN

Explanation in artificial intelligence: Insights from the social sciences

http://emamispnu.persiangig.com/Projects/Cloud%20Computing/science_2.pdf

Review: A survey on security issues in service delivery models of cloud computing

Our goal in this paper is to introduce and motivate a methodology, called Tropos,1 for building agent oriented software systems. Tropos is based on two key ideas. First, the notion of agent and all related mentalistic notions (for instance goals and plans) are used in all phases of software development, from early analysis down to the actual implementation. Second, Tropos covers also the very early phases of requirements analysis, thus allowing for a deeper understanding of the environment where the software must operate, and of the kind of interactions that should occur between software and human agents. The methodology is illustrated with the help of a case study. The Tropos language for conceptual modeling is formalized in a metamodel described with a set of UML class diagrams.

/pdf/tropos-an-agent-oriented-software-development-methodology-4cfpp4zfvj.pdf

Tropos: An Agent-Oriented Software Development Methodology

Over the Internet today, computing and communications environments are significantly more complex and chaotic than classical distributed systems, lacking any centralized organization or hierarchical control. There has been much interest in emerging Peer-to-Peer (P2P) network overlays because they provide a good substrate for creating large-scale data sharing, content distribution, and application-level multicast applications. These P2P overlay networks attempt to provide a long list of features, such as: selection of nearby peers, redundant storage, efficient search/location of data items, data permanence or guarantees, hierarchical naming, trust and authentication, and anonymity. P2P networks potentially offer an efficient routing architecture that is self-organizing, massively scalable, and robust in the wide-area, combining fault tolerance, load balancing, and explicit notion of locality. In this article we present a survey and comparison of various Structured and Unstructured P2P overlay networks. We categorize the various schemes into these two groups in the design spectrum, and discuss the application-level network performance of each group.

/pdf/a-survey-and-comparison-of-peer-to-peer-overlay-network-cpcv2ij1hk.pdf

A survey and comparison of peer-to-peer overlay network schemes

We are mainly interested in the development of CAD systems for interior design. An effective use of such systems relies to a large extent on the characteristics of their user interface. This paper describes NALIG, a system able to "understand" and "reason about" high level descriptions of spatial scenes. The user interacts with the system by using a natural language interface which, though very simple, is expressive enough to allow the description of complex configurations of objects. NALIG replies by drawing on the screen an image mirroring its own "understanding" of the scene described. The comprehension process has required the integration of different AI-techniques (e.g., natural language understanding, spatial reasoning, default and common sense reasoning).

Visual representation of natural language scene descriptions

The aim of this paper is to discuss the potentials, problems and critical factors for the industrial usage of mechanized theorem proving. The approach followed in this paper is somehow unusual. The starting point is the results of an industrial project whose goal was the assessment of the state of the art of provers (and of tools supporting formal methods in general). We describe the project results in terms of evaluation criteria, classification of technologies and tools and critical factors for industrial take-up. We present the results of the assessment in the same spirit, the same kind of analysis and even the same terminology which were used in the presentations and in the deliverables of the project. This should result in a presentation of a “different view” of the problem of technology transfer in theorem proving, that we call the “user’s point of view”. In this way, we hope to give a new perspective in the discussion of the industrial take-up of the theorem proving technology.

Theorem proving in technology transfer: the user’s point of view

In this paper we present a first order classical metatheory, called MT, with the following properties: (1) tactics are terms of the language of MT (we call these tactics,Logic Tactics); (2) there exists a mapping between Logic Tactics and the tactics developed as programs within the GETFOL theorem prover (we call these tactics,Program Tactics). MT is expressive enough to represent the most interesting tacticals, i.e.,then, orelse, try, progress andrepeat. repeat allows us to express Logic Tactics which correspond to Program Tactics which may not terminate. This work is part of a larger project which aims at the development and mechanization of a metatheory which can be used to reason about, extend and, possibly, modify the code implementing Program Tactics and the GETFOL basic inference rules.

Program tactics and logic tactics

Presents a system for intelligent robot navigation Its main feature is the ability to integrate goal directed planning with information acquisition from the external world, and with reaction to failure This ability is obtained by means of a two-layered architecture: the higher (strategical) level controls the activation of the modules of the lower (navigation) level, which can perform, in different ways, basic tasks such as path planning, activation of navigation and processing of information acquired from the external environment By programming the strategical level with the suitable strategies, the system can control navigation with sophisticated modalities >

Navigation by combining reactivity and planning

We present new planning and learning algorithms for RAE, the Refinement Acting Engine. RAE uses hierarchical operational models to perform tasks in dynamically changing environments. Our planning procedure, UPOM, does a UCT-like search in the space of operational models in order to find a near-optimal method to use for the task and context at hand. Our learning strategies acquire, from online acting experiences and/or simulated planning results, a mapping from decision contexts to method instances as well as a heuristic function to guide UPOM. Our experimental results show that UPOM and our learning strategies significantly improve RAE's performance in four test domains using two different metrics: efficiency and success ratio.

Paolo Traverso

Papers

Visual representation of natural language scene descriptions

Theorem proving in technology transfer: the user’s point of view

Program tactics and logic tactics

Navigation by combining reactivity and planning

Integrating Acting, Planning and Learning in Hierarchical Operational Models