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Full-Text Articles in Physical Sciences and Mathematics

Universal Access In Digital Libraries, Igg Adiwijaya May 2000

Universal Access In Digital Libraries, Igg Adiwijaya

Theses

Digital libraries are concerned with the creation and management of information sources, the movement of information across global networks and the effective use of this information by a wide range of users. A digital library is a vast collection of obj ects that are of multimedia nature, e.g., text, video, images, and audio. Users wishing to access the digital library objects may possess varying capabilities, preferences, domain expertise, and may use different information appliances. With the phenomenal growth of the Internet, the number of different information appliances will, if not already, increase substantially in the near future. Facilitating access to …


Development And Characterization Of Techniques For Neuro-Imaging Registration, Carlo Ciulla May 2000

Development And Characterization Of Techniques For Neuro-Imaging Registration, Carlo Ciulla

Theses

Three automated techniques were developed for the alignment of Neuro-Images acquired during distinct scanning periods and their performance were characterized. The techniques are based on the assumption that the human brain is a rigid body and will assume different positions during different scanning periods. One technique uses three fiducial markers, while the other two uses eigenvectors of the inertia matrix of the Neuro-Image, to compute the three angles (pitch, yaw and roll) needed to register the test Neuro-Image to the reference Neuro-Image. A rigid body transformation is computed and applied to the test Neuro-Image such that it results aligned to …


Automatic Categorization Of Abstracts Through Bayesian Networks, William Ramirez Jan 2000

Automatic Categorization Of Abstracts Through Bayesian Networks, William Ramirez

Theses

This thesis presents a method for assigning abstracts of Artificial Intelligence papers to their area of the field. The technique is implemented by the use of a Bayesian network where relevant keywords extracted from the abstract being categorized, are entered as evidence and inferencing is made to determine potential subject areas. The structure of the Bayesian network represents the causal relationship between Artificial Intelligence keywords and subject areas. Keyword components of the network are selected from precategorized abstracts. The work reported here is part of a larger project to automatically assign papers to reviewers for Artificial Intelligence conferences. The process …


Integration Of Multi Lifecycle Assessment And Design For Environment Database Using Relational Moddel Concepts, Bhagyashree Suratran Jan 2000

Integration Of Multi Lifecycle Assessment And Design For Environment Database Using Relational Moddel Concepts, Bhagyashree Suratran

Theses

Multi-lifecycle Assessment (MLCA) systematically considers and quantifies the consumption of resources and the environmental impact associated with a product or process. Design challenges posed by a multi-lifecycle strategy are significantly more complex than traditional product design. The designer must look forward in time to maximize the product's end-of-life yield of assemblies, parts and materials while looking backward to the world of existing products for feedstock sources for the current design. As MLCA and DEE share some common data items, such as, part geometry, material and manufacturing process, it is advantageous to integrate the database for MLCA and DEE. The integration …


A Visualization System For Information Retrieval And Mining In High Dimensional Databases, Xinhuan Zheng Jan 2000

A Visualization System For Information Retrieval And Mining In High Dimensional Databases, Xinhuan Zheng

Theses

In this thesis, we present a search engine capable of giving good heuristic answers to the queries on a structural database. A structural database holds structural objects, e.g., protein secondary and tertiary structures, 3D molecules, phylogenetic trees, neuroanatomical networks, parse trees, CAD/CAM parts, and XML documents. Answering queries on such databases often requires solving variants of the graph isomorphism or subisomorphism problems. We also describe a graphic user interface which interacts with users to facilitate visualizing query results. We use 3D molecules (graphs) as illustrating examples, though our prototype is able to handle many other different types of structural data.


Analysis Of Clustering Algorithms For Spike Sorting Of Multiunit Extracellular Recordings, Jayesh Rege Jan 2000

Analysis Of Clustering Algorithms For Spike Sorting Of Multiunit Extracellular Recordings, Jayesh Rege

Theses

Various techniques have been considered in the past to identify distinct spike shapes from mulitunit extracellular recording. These techniques involve adaptive filtering techniques or template matching techniques or hierarchical clustering techniques. In this investigation, we have used Principal Component Analysis followed by various clustering techniques to identify distinct spike shapes. The amplitude filter is used to separate spikes from background neuronal activity. The correlation matrix of the spike data is used to compute principal component wave forms. Each spike is thus represented by the coefficients of principal components. Then, We have used agglomorative hierarchical clustering algorithm to perform the initial …


Security In Distributed Systems - A Framework For Different Application Types, Ingo Stengel Jan 2000

Security In Distributed Systems - A Framework For Different Application Types, Ingo Stengel

Theses

Security is a factor which decides upon the applicability of distributed applications. Therefore this thesis deals with security in distributed systems. The complexity of the existing distributed technologies makes it necessary to reduce the number of distributed technologies considered in this thesis, i.e. concentrating on: Java, Mobile Agents and CORBA, where only Java-based mobile agents will be considered.

After a short review of basic security principles including firewalls, existing security problems in the above mentioned distributed technologies are analysed. Additional generic problems in distributed systems are outlined.

Solutions are referring to two different areas: those regarding security problems with firewalls …