Satyajeet Raje

A Synergistic Framework for Geographic Question Answering

QA (question answering) systems designated for answering in-depth geographic questions are highly demanded but not quite available. Previous research has visited various individual aspects of a QA system but few synergistic frameworks have been proposed. This paper investigates the nature of geographic question formation and observes their unique linguistic structures that can be semantically translated into a spatial query. We create a new task of solving non-trivial questions using GIS (Geographic Information System) and test it with an associated corpus. A dynamic programming algorithm is developed for classification and voting algorithm for verification. Two types of ontologies are integrated for disambiguating and discriminating spatial terms. PostGIS serves as the GIS backend to provide domain expertise for spatial reasoning. Results show that exact answers can be returned quickly and correctly by our system. Contrast classification results in improved accuracy compared with the baseline which proves the effectiveness of proposed methods.

Using ontology-based methods for implementing role-based access control in cooperative systems

The issue of security of data becomes very critical due to the federated databases that cooperative systems integrate. In this paper, we describe a role-based access control (RBAC) mechanism that can be applied to collaborative project organizations, and which uses ontology-based methods for its implementation. This eases the process of making modifications. It also brings about standardization, which is cornerstone for portability. We test and evaluate this approach in an implementation of a data-management system for proteomic experiment data. The primary aim of this study is, firstly, to make use of an upcoming and potentially standard technology and apply it to the domain of database security. Our second aim is to validate the hypothesis that such a method can be effectively used in a real-world cooperative system.

Implementation and Evaluation of Commodity Hardware and Software in an Open World Spoken Dialog Framework

Several published papers describe various frameworks to implement an Open World Dialog system. This research conducts a critical review of one system using commodity hardware and software, independent of the vendor and authors. The results delineate the parts of the system that are implemented via the SDK and identify the components that require development. Furthermore, we estimate the difficulty of implementing each component of the dialog system using the SDKs.

Using Semantic Web Technologies for RBAC in Project-Oriented Environments

Project-oriented environments are key to supporting the co-operative work essential to collaborative research activities. However, personnel and resources in project-oriented environments are typically diverse and heterogeneous as they come from both internal as well as external domains. Providing a robust data security system in such an environment becomes critical. The ideal access control architecture should manage access to resources not only based on roles but also based on the specific nature of each resource and its involvement within the project. Traditional role-based access control (RBAC) does not consider the context which often modifies the responsibility given to resources. We propose using an enhanced role-based access control (RBAC) mechanism to address this problem. Specifically, we discuss the implementation of RBAC using ontological methods borrowed from semantic web technology. We used an ontology-based approach for specification and implementation of the RBAC in a collaborative system used within a research group to manage proteomics data, where the access control policy depends on how the project team hierarchy is structured. We describe the design and implementation of this system in this paper. We also provide a preliminary evaluation of the implementation. We find there are several advantages to using ontological methods to implement RBAC. The most significant of these is standardization, which is essential for portability. Also key is modifiability as the actual roles are defined by the ontology itself. Since data access is provided through URI handling moving to a federated system is made easier. This becomes very important in collaborative environments as the data in question is invariably distributed.