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A
Projection-Synthesis Approach to Determine the Lossless-Join
Property of Schema Decompositions
-- P S Gill
A
global schema has to undergo decomposition on the basis of
its functional dependencies to obtain a set of projections,
normalized to the desired degree. These projections then form
a set of schemas of the desired database. During the process
of normalization, one of the mandatory requirements is to
make sure that the decompositions are lossless-join decompositions.
But suppose a set of projections are presented as decomposition
of global schema, there exist some algorithms, viz., ABU's
Algorithm (Aho and Ullman, 1979) and a Graph- Based Algorithm
(Gill and Patnaik, 2007) that determine whether the decomposition
is lossless-join decomposition or not. This paper proposes
a `Projection-Synthesis' to determine the lossless-join property
of a given set of projections. Additionally, the proposed
algorithm will also determine if there exists any redundancy
amongst the projections that can be eliminated without the
loss of any information.
©
2008 The Icfai University Press. All Rights Reserved.
Another
Linear Time Algorithm for Guard Zone Problem --
Rajat K Pal, Ranjan Mehera and Sarit Chatterjee
Given
a simple polygon P, its guard zone G (of width
r) is a closed region, consisting of straight line
segments and circular arcs (of radius r), bounding
the polygon P such that there exists no pair of points
p (on the boundary of P) and q (on the
boundary of G) having their Euclidean distance d(p,q)
less than r. In this paper, we have designed a time-optimal
sequential algorithm to solve the guard zone problem.
©
2008 The Icfai University Press. All Rights Reserved.
A
New Computer-Oriented Approach to the Solution of Large-Scale
Multi-Objective Optimization Problems --
Meyyappan T and Sakthivel S
Most
real-world search and optimization problems naturally involve
multiple objectives. Because of lack of suitable solution
methodologies, Multi-objective optimization has been mostly
cast and solved as single-objective optimization problem.
A solution that is extreme with respect to one objective requires
a compromise in other objectives. The majority of the available
methods transform multiple objectives into a single-objective
optimization. In this paper, the authors propose a new algorithm
to find an optimal solution for multi-objective optimization
problems keeping the given objectives as they are. The given
objectives or constraints are not transformed to any form.
In this way, the authors approach the multi-objective optimization
problem in a new pattern. A few problems are solved using
single-objective optimization method, considering one objective
at a time. The same problems are solved using the proposed
algorithm. The authors employ fractional programing concepts
to obtain the best optimal solution. The results obtained
from the new algorithm is found to be good compared to single-objective
optimization methods.
©
2008 The Icfai University Press. All Rights Reserved.
An
Intelligent Agent for Extracting Data from Flat and Nested
Records -- S Vasavi and L
S S Reddy
This
paper presents automatic extraction of data and schema from
web pages. Data and schema, thus extracted, can be integrated
for providing value-added services. Existing automatic techniques
have poor performance at noise filtration or data extraction.
They either use visual clues or specific tags to locate the
data regions. In this paper, the authors propose an intelligent
and effective agent Intelligent system for Data eXchange (IDX
) for extraction. The agent uses a combination of visual clues
and specific tags to identify and filter noise from nested
and flat data records. Regular expression grammar is used
to extract the approximate schema of web data. Experiments
conducted on various web pages proved that the agent is intelligent,
accurate (at noise filtration and data extraction) and performs
better than the existing techniques.
©
2008 The Icfai University Press. All Rights Reserved.
Reasoning
with Event Durations in Natural Language Text --
Suresh Kumar Sanampudi and G Vijaya Kumari
In
this paper we propose a novel method for event ordering in
natural language text using a constraint satisfaction problem.
The events described in text narratives do not always occur
in a linear/chronological order and a text summarizer would
be highly benefited, given a linear ordering of events in
the text. This paper describes an approach for modeling the
events in text as event intervals. We model a natural language
text as a binary constraint network where each node represents
an event in the text, and the binary relationship between
a pair of events is encoded as the disjunction of the INDU
(interval duration) relations. The INDU framework is employed
for the event ordering purpose. The reasoning algorithm in
the framework is used to propagate the constraints in the
network and thus instantiate the relative ordering of the
events globally. We make use of the popular Time ML for identifying
the relative durations. Extensive experimentations were performed
on a well-known dataset (Time Bank) and the results were found
to be encouraging.
©
2008 The Icfai University Press. All Rights Reserved.
When
a Degree Sequence Represents a
Tree Sequence --
Saptarshi Naskar,
Krishnendu Basuli and Samar Sen Sarma
A
sequence of nonnegative integers can represent degrees of
a graph. This conclusion is true when there is an already
established condition. The sequence called graphic sequence
may represent a tree. The objective of this paper is to show
that a similar sequence represents the degrees of vertices
of a tree. The only fallacy of the conclusion is that there
may be graphs which are not trees and may have the same degree
sequence.
©
2008 The Icfai University Press. All Rights Reserved.
Measuring
the Vulnerability of Nodes in an Ad Hoc Network Using
Analytical Hierarchy Process Model --
S
Sujatha, A Kannan and P Vivekanandan
The
wireless communication is gaining importance due to the fast
and drastic rate of evolution and emergence of mobile communication
gadgets. The lack of any central coordination and shared medium
makes ad hoc networks more vulnerable to security attacks.
Hence, it becomes necessary to provide high level of security
for the applications running on ad hoc networks. This
paper aims to analyze the performance of an Ad hoc
On-Demand Distance Vector (AODV) routing protocol using on-line
monitoring of the routing information present in the nodes.
The routing table which is updated dynamically contains data
which gives details of all the routes in an ad hoc network.
The parameters required to decide the vulnerability are obtained
directly or derived from the routing tables. In this work,
Analytical Hierarchy Process (AHP) tool is used to analyze
the network based on the parameters and decide the vulnerabilities
of nodes. The vulnerability measures from this system can
be used by network administrators to decide the type and level
of security to be provided.
©
2008 The Icfai University Press. All Rights Reserved.
A
Semantic-Based Approach for Automatic Story Generation Using
Multi-Agent Framework -- A
Jaya and G V Uma
The
spirit behind story generation is to hold the reader's
interest throughout. An agent's role is very essential in
the automatic construction of stories in a computer system.
They understand their environment through the perception sequence,
which in turn is perceived by the perceptors, and generates
output accordingly through actuators. An intelligent software
agent is a piece of software that works for the users, which
perceives the environment acted upon through the actuators
and performs specified tasks optimistically without human
assistance. The multi-agent system supports the story generation
in an efficient and meaningful way. Each agent has its own
responsibility and scope. An agent for story generation concentrates
on the theme instantiation and creation of new plots for interesting
stories, and in the same way, the language generation agent
focuses on the creation of meaningful sentences for the stories.
Collaboration of these agents yields a good and interesting
story. The present approach focuses on the construction of
simple stories in the most significant way using agents.
©
2008 The Icfai University Press. All Rights Reserved.
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July
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