DSHOP: Distributed simple hierarchical ordered planner.

Planning has been an important subject in the area of Artificial Intelligence (AI) for over three decades. Planning is the problem of seeking a series of actions (that is, a plan) that will accomplish a desired goal. Most planning approaches rely on a single processor or a single-agent paradigm. Unfortunately, in a complex world, a single agent may not be sufficient to optimally solve the problem. Distributed Planning is a sub-field of Distributed AI that involves multi-agents working together to solve large planning problems. Distribution may speed up the traditional planning system through parallelism. Hierarchical Task Network (HTN) planning is an AI planning methodology that creates plans by task decomposition. SHOP (Simple Hierarchical Ordered Planner) is a domain-independent HTN planning system designed by Dana Nau et al. that plans for tasks in the same order that they will later be executed. This thesis aims at designing and implementing a distributed version of SHOP (that is, DSHOP) and running it on a high performance distributed system called SHARCNET. The implementation is based upon Message Passing Interface (MPI), that is, a library of functions used to achieve parallelism via message-passing. We investigate two approaches to share work between processors: state-copying and state-recomputation. We implemented a state-copying based DSHOP system (DSHOPC), and a state-recomputation based DSHOP system (DSHOPR). We compared these two implementations of DSHOP with the Java version of SHOP on a set of randomly generated artificial domains. A set of experimental results has been used to evaluate the performance of the DSHOP algorithm.Dept. of Computer Science. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2004 .L83. Source: Masters Abstracts International, Volume: 43-01, page: 0240. Advisers: Scott Goodwin; Froduald Kabanza. Thesis (M.Sc.)--University of Windsor (Canada), 2004

Proceedings of the NASA Conference on Space Telerobotics, volume 5

Papers presented at the NASA Conference on Space Telerobotics are compiled. The theme of the conference was man-machine collaboration in space. The conference provided a forum for researchers and engineers to exchange ideas on the research and development required for the application of telerobotics technology to the space systems planned for the 1990's and beyond. Volume 5 contains papers related to the following subject areas: robot arm modeling and control, special topics in telerobotics, telerobotic space operations, manipulator control, flight experiment concepts, manipulator coordination, issues in artificial intelligence systems, and research activities at the Johnson Space Center

2019-2020, University of Memphis bulletin

University of Memphis bulletin containing the graduate catalog for 2019-2020.https://digitalcommons.memphis.edu/speccoll-ua-pub-bulletins/1439/thumbnail.jp

Multipath: un sistema para la programación lógica

Postprint (published version

2020-2021, University of Memphis bulletin

University of Memphis bulletin containing the graduate catalog for 2020-2021.https://digitalcommons.memphis.edu/speccoll-ua-pub-bulletins/1440/thumbnail.jp

Dependability Assessment of Wireless Sensor Networks with Formal Methods

Wireless Sensor Networks (WSNs) are increasingly being adopted in critical applications, where verifying the correct operation of sensor nodes is a major concern. Undesired events, such as node crash and packet loss, may undermine the dependability of the WSN. Hence their effects need to be properly assessed from the early stages of the development process onwards to minimize the chances of unexpected problems during use. It is also necessary to monitor the system during operation in order to avoid unexpected results or dangerous effects. In this thesis we propose a framework to investigate the correctness of the design of a WSN from the point of view of its dependability, i.e., resilience to undesired events. The framework is based on the Event Calculus formalism and it is backed-up by a support tool aimed to simplify its adoption by system designers. The tool allows to specify the target WSN in a user-friendly way and it is able to generate automatically the Event Calculus specifications used to check correctness properties and evaluate dependability metrics, such as connection resiliency, coverage and lifetime. It is able to work at design time and runtime. In particular at runtime the tool works a server that is in waiting for new events coming from the WSN and, performed the reasoning using the same specifications, is able to do prediction about future criticalities of the WSN. The effectiveness of the approach is shown in the context of five case studies, aiming to illustrate how the framework is helpful to drive design choices by means of what-if scenario analysis and robustness checking, and to check the correctness properties of the WSN at runtime

Feature based workshop oriented NC planning for asymmetric rotational parts

This thesis describes research which is aimed at devising a framework for a feature based workshop oriented NC planning. The principal objective of this thesis is to utilize a feature based method which can rationalize and enhance part description and in particular part planning and programming on the shop-floor. This work has been done taking into account new developments in the area of shop floor programming. The importance of the techniques and conventions which are addressed in this thesis stems from the recognition that the most effective way to improve and enhance part description is to capture the intent of the engineering drawing by devising a medium in which the recurring patterns of turned components can be modelled for machining. Experimental application software which allows the user to describe the workpiece and subsequently generate the manufacturing code has been realized