Malay A Dutta | Indian Institute of Information Technology Guwahati (original) (raw)

Papers by Malay A Dutta

2008 16th International Conference on Advanced Computing and Communications, 2008

This paper presents a privacy preserving clustering technique using hybrid approach. The techniqu... more This paper presents a privacy preserving clustering technique using hybrid approach. The technique mainly exploits a combination of isometric transformations i.e. translation, rotation and reflection transformations along with a secure random function in order to provide secrecy of user-specified attributes without losing accuracy in results. The proposed method was tested and evaluated in terms of several synthetic as well as

International Journal of Business Information Systems, 2016

To facilitate efficient query processing in data warehouses and develop On Line Analytical Proces... more To facilitate efficient query processing in data warehouses and develop On Line Analytical Processing (OLAP) for decision support systems, intermediate data derived in the middle of complex processing may be stored as a set of materialized views. It is not possible to save each and every intermediate query result due to limitation of space and updating cost. Therefore, an optimum set of views need to be selected for materialization and, this requires a good optimization technique. Many approaches have been presented in the literature to achieve good solutions to this problem. In this paper we attempt to provide a comprehensive survey of the approaches and algorithms introduced to address the issue. We also attempt to identify the key issues and research challenges in this area.

This paper presents an efficient spatial indexing technique based on silhouette moments that make... more This paper presents an efficient spatial indexing technique based on silhouette moments that makes the index robust subject to the three basic transformations for content-based image retrieval. Spatial index is generated based upon a fast and robust clustering technique, which can recognize color clusters of any shape. The new clustering technique has been found to be efficient in terms of time complexity and cluster quality than many of its counterparts. The indices are stored in a spatial cluster and object tree, which is a variant of B-tree that helps in speeding up the retrieval performance. A matching engine has been devised to retrieve images from the image database, which has the capacity for global and regional similarity search. Based on experimentation, the performance of the new indexing technique has been found to be better than its counterparts providing for robust and compact index, better analysis of the color content of the image, higher precision and recall in retrieval and better retrieval time.

Geometric Modeling and Imaging--New Trends (GMAI'06), 2006

This paper presents an efficient spatial indexing technique based on Silhouette moments that make... more This paper presents an efficient spatial indexing technique based on Silhouette moments that makes the index robust subject to the three basic transformations for CBIR. Spatial index is generated based upon a fast and robust clustering technique, which can recognize color clusters of any shape. The new clustering technique has been found to be efficient in terms of time complexity

Advances in Intelligent and Soft Computing, 2012

By saving or materializing a set of derived relations or intermediate results from base relations... more By saving or materializing a set of derived relations or intermediate results from base relations of a data warehouse, the query processing can be made more efficient. It avoids repeated generation of these temporary views while generating the query responses. But as in case of a data warehouse there may be large number of queries containing even larger number of views inside each query, it is not possible to save each and every query due to constraint of space and maintenance costs. Therefore, an optimum set of views are to be selected for materialization and hence there is the need of a good technique for selecting views for materialization. Several approaches have been made so far to achieve a good solution to this problem. In this paper an attempt has been made to solve this problem by using Multi Objective Simulated Annealing(MOSA) and Archived Multi-Objective Simulated Annealing(AMOSA) algorithm.

Applied Algorithms, 2014

A similarity measure for gene expression data should give the shapes of the patterns of the gene ... more A similarity measure for gene expression data should give the shapes of the patterns of the gene expression data and should be less susceptible to outliers. In this paper, we present a similarity measure for clustering gene expression time series data. Our similarity measure, PWCTM, uses the pairwise changing tendency measure of every pair of conditions. We have compared our measure with several proximity measures using k-means clustering algorithm in terms of Silhouette index, z-score and p-value. Our experimental results indicate that the gene clusters obtained with PWCTM as the similarity measure are biologically significant in the respective clusters due to their low p-values and high z-values.

Transactions of the American Mathematical Society, 1980

Let G be a locally compact group and A an arbitrary Banach space. L p ( G , A ) {L^p}(G,A) will d... more Let G be a locally compact group and A an arbitrary Banach space. L p ( G , A ) {L^p}(G,A) will denote the space of p-integrable A-valued functions on G. M ( G , A ) M(G,A) will denote the space of regular A-valued Borel measures of bounded variation on G. In this paper, we characterise the relatively compact subsets of L p ( G , A ) {L^p}(G,A) . Using this result, we prove that if μ ∈ M ( G , A ) \mu \, \in \, M(G,A) , such that either x → μ x x\, \to \, {\mu _x} or x → x μ x{ \to _x}\mu is continuous, then μ ∈ L 1 ( G , A ) \mu \, \in \, {L^1}(G,A) .

Proceedings of the American Mathematical Society, 1981

Let G be a locally compact abelian group and A" be a Banach space. Let Ll(G, X) be the Banach spa... more Let G be a locally compact abelian group and A" be a Banach space. Let Ll(G, X) be the Banach space of X-valued Bochner integrable functions on G. We prove that the space of bounded linear translation invariant operators of L'(G, X) can be identified with L(X, M(G, X)), the space of bounded linear operators from X into M(G, X) where M(G, X) is the space of Jf-valued regular, Borel measures of bounded variation on G. Furthermore, if A is a commutative semisimple Banach algebra with identity of norm 1 then L\G, A) is a Banach algebra and we prove that the space of multipliers of L\G, A) is isometrically isomorphic to M{G, A). It also follows that if dimension of A is greater than one then there exist translationinvariant operators of Ll(G, A) which are not multipliers of L1(G, A).

Proceedings of the American Mathematical Society, 1978

Let T be a multiplier of a Segal algebra S on a locally compact abelian group G. We prove that T ... more Let T be a multiplier of a Segal algebra S on a locally compact abelian group G. We prove that T 2 ( S ) {T^2}(S) is closed if and only if T is a product of an idempotent and an invertible multiplier. We also show that the techniques developed in the proof of this theorem can be used to obtain some other known results.

Pattern Recognition Letters, 2005

The ROCK algorithm is an agglomerative hierarchical clustering algorithm for clustering categoric... more The ROCK algorithm is an agglomerative hierarchical clustering algorithm for clustering categorical data [Guha S.,

Microwave and Optical Technology Letters, 2004

Coax-fed inverted L-shaped microstrip antennas and parasitically coupled inverted L-microstrip an... more Coax-fed inverted L-shaped microstrip antennas and parasitically coupled inverted L-microstrip antennas are presented. The inverted L-shaped microstrip antenna gives an impedance bandwidth of 30.6%, which is increased to 33.7% by parasitic coupling. The bandwidth has been achieved with a substrate thickness of 2 mm. Radiation patterns and gains are also studied and presented.

Microwave and Optical Technology Letters, 2005

Basic standard for the measurement of specific absorption rate related to human exposure to elect... more Basic standard for the measurement of specific absorption rate related to human exposure to electromagnetic fields from mobile phones (300 MHz-3 GHz), European standard, 2001.

Microwave and Optical Technology Letters, 2004

Both genetic algorithms (GAs) and artificial neural networks (ANNs) have been used in the field o... more Both genetic algorithms (GAs) and artificial neural networks (ANNs) have been used in the field of computational electromagnetics as the most powerful optimizing tools. In this paper, a simple and efficient method is presented to handle the problem of competing convention while training an ANN by using a GA. This technique is applied to calculate the resonant frequency of a thick-substrate rectangular microstrip antenna (RMA). The training time is less than that of a normal feed-forward backpropagation algorithm. The measured results are in very good agreement with experimental results.

Microwave and Optical Technology Letters, 2006

The resonance frequency of an E-shaped microstrip antenna has been calculated by equating its are... more The resonance frequency of an E-shaped microstrip antenna has been calculated by equating its area to an equivalent area of a rectangular microstrip patch antenna. A new expression for effective dielectric constant is developed for the E-shaped microstrip patch antenna. The new expression of resonance frequency is used to calculate the results, which are in good agreement with the measured and published results.

Microbiological Research, 2010

We have done a comparative study of tRNA diversity and total tRNA genes among different strains o... more We have done a comparative study of tRNA diversity and total tRNA genes among different strains of bacteria with respect to the optimum growth temperature of the cells. Our observation suggests that higher tRNA diversity usually occurs in thermophiles in comparison to non-thermophiles. Among psychrophiles total tRNA was observed to be more than twofold higher than in the non-psychrophiles. Though tRNA diversity and total tRNA have recently been shown to be affected by an organism's genomic GC% and growth rate, this work is the first report on growth temperature affecting these features in bacteria. This work extends the list of molecular features undergoing adaptation due to growth temperature and supports the view that growth temperature acts as a selecting factor at the molecular level during evolution.

2008 16th International Conference on Advanced Computing and Communications, 2008

This paper presents a privacy preserving clustering technique using hybrid approach. The techniqu... more This paper presents a privacy preserving clustering technique using hybrid approach. The technique mainly exploits a combination of isometric transformations i.e. translation, rotation and reflection transformations along with a secure random function in order to provide secrecy of user-specified attributes without losing accuracy in results. The proposed method was tested and evaluated in terms of several synthetic as well as

International Journal of Business Information Systems, 2016

To facilitate efficient query processing in data warehouses and develop On Line Analytical Proces... more To facilitate efficient query processing in data warehouses and develop On Line Analytical Processing (OLAP) for decision support systems, intermediate data derived in the middle of complex processing may be stored as a set of materialized views. It is not possible to save each and every intermediate query result due to limitation of space and updating cost. Therefore, an optimum set of views need to be selected for materialization and, this requires a good optimization technique. Many approaches have been presented in the literature to achieve good solutions to this problem. In this paper we attempt to provide a comprehensive survey of the approaches and algorithms introduced to address the issue. We also attempt to identify the key issues and research challenges in this area.

This paper presents an efficient spatial indexing technique based on silhouette moments that make... more This paper presents an efficient spatial indexing technique based on silhouette moments that makes the index robust subject to the three basic transformations for content-based image retrieval. Spatial index is generated based upon a fast and robust clustering technique, which can recognize color clusters of any shape. The new clustering technique has been found to be efficient in terms of time complexity and cluster quality than many of its counterparts. The indices are stored in a spatial cluster and object tree, which is a variant of B-tree that helps in speeding up the retrieval performance. A matching engine has been devised to retrieve images from the image database, which has the capacity for global and regional similarity search. Based on experimentation, the performance of the new indexing technique has been found to be better than its counterparts providing for robust and compact index, better analysis of the color content of the image, higher precision and recall in retrieval and better retrieval time.

Geometric Modeling and Imaging--New Trends (GMAI'06), 2006

This paper presents an efficient spatial indexing technique based on Silhouette moments that make... more This paper presents an efficient spatial indexing technique based on Silhouette moments that makes the index robust subject to the three basic transformations for CBIR. Spatial index is generated based upon a fast and robust clustering technique, which can recognize color clusters of any shape. The new clustering technique has been found to be efficient in terms of time complexity

Advances in Intelligent and Soft Computing, 2012

By saving or materializing a set of derived relations or intermediate results from base relations... more By saving or materializing a set of derived relations or intermediate results from base relations of a data warehouse, the query processing can be made more efficient. It avoids repeated generation of these temporary views while generating the query responses. But as in case of a data warehouse there may be large number of queries containing even larger number of views inside each query, it is not possible to save each and every query due to constraint of space and maintenance costs. Therefore, an optimum set of views are to be selected for materialization and hence there is the need of a good technique for selecting views for materialization. Several approaches have been made so far to achieve a good solution to this problem. In this paper an attempt has been made to solve this problem by using Multi Objective Simulated Annealing(MOSA) and Archived Multi-Objective Simulated Annealing(AMOSA) algorithm.

Applied Algorithms, 2014

A similarity measure for gene expression data should give the shapes of the patterns of the gene ... more A similarity measure for gene expression data should give the shapes of the patterns of the gene expression data and should be less susceptible to outliers. In this paper, we present a similarity measure for clustering gene expression time series data. Our similarity measure, PWCTM, uses the pairwise changing tendency measure of every pair of conditions. We have compared our measure with several proximity measures using k-means clustering algorithm in terms of Silhouette index, z-score and p-value. Our experimental results indicate that the gene clusters obtained with PWCTM as the similarity measure are biologically significant in the respective clusters due to their low p-values and high z-values.

Transactions of the American Mathematical Society, 1980

Let G be a locally compact group and A an arbitrary Banach space. L p ( G , A ) {L^p}(G,A) will d... more Let G be a locally compact group and A an arbitrary Banach space. L p ( G , A ) {L^p}(G,A) will denote the space of p-integrable A-valued functions on G. M ( G , A ) M(G,A) will denote the space of regular A-valued Borel measures of bounded variation on G. In this paper, we characterise the relatively compact subsets of L p ( G , A ) {L^p}(G,A) . Using this result, we prove that if μ ∈ M ( G , A ) \mu \, \in \, M(G,A) , such that either x → μ x x\, \to \, {\mu _x} or x → x μ x{ \to _x}\mu is continuous, then μ ∈ L 1 ( G , A ) \mu \, \in \, {L^1}(G,A) .

Proceedings of the American Mathematical Society, 1981

Let G be a locally compact abelian group and A" be a Banach space. Let Ll(G, X) be the Banach spa... more Let G be a locally compact abelian group and A" be a Banach space. Let Ll(G, X) be the Banach space of X-valued Bochner integrable functions on G. We prove that the space of bounded linear translation invariant operators of L'(G, X) can be identified with L(X, M(G, X)), the space of bounded linear operators from X into M(G, X) where M(G, X) is the space of Jf-valued regular, Borel measures of bounded variation on G. Furthermore, if A is a commutative semisimple Banach algebra with identity of norm 1 then L\G, A) is a Banach algebra and we prove that the space of multipliers of L\G, A) is isometrically isomorphic to M{G, A). It also follows that if dimension of A is greater than one then there exist translationinvariant operators of Ll(G, A) which are not multipliers of L1(G, A).

Proceedings of the American Mathematical Society, 1978

Let T be a multiplier of a Segal algebra S on a locally compact abelian group G. We prove that T ... more Let T be a multiplier of a Segal algebra S on a locally compact abelian group G. We prove that T 2 ( S ) {T^2}(S) is closed if and only if T is a product of an idempotent and an invertible multiplier. We also show that the techniques developed in the proof of this theorem can be used to obtain some other known results.

Pattern Recognition Letters, 2005

The ROCK algorithm is an agglomerative hierarchical clustering algorithm for clustering categoric... more The ROCK algorithm is an agglomerative hierarchical clustering algorithm for clustering categorical data [Guha S.,

Microwave and Optical Technology Letters, 2004

Coax-fed inverted L-shaped microstrip antennas and parasitically coupled inverted L-microstrip an... more Coax-fed inverted L-shaped microstrip antennas and parasitically coupled inverted L-microstrip antennas are presented. The inverted L-shaped microstrip antenna gives an impedance bandwidth of 30.6%, which is increased to 33.7% by parasitic coupling. The bandwidth has been achieved with a substrate thickness of 2 mm. Radiation patterns and gains are also studied and presented.

Microwave and Optical Technology Letters, 2005

Basic standard for the measurement of specific absorption rate related to human exposure to elect... more Basic standard for the measurement of specific absorption rate related to human exposure to electromagnetic fields from mobile phones (300 MHz-3 GHz), European standard, 2001.

Microwave and Optical Technology Letters, 2004

Both genetic algorithms (GAs) and artificial neural networks (ANNs) have been used in the field o... more Both genetic algorithms (GAs) and artificial neural networks (ANNs) have been used in the field of computational electromagnetics as the most powerful optimizing tools. In this paper, a simple and efficient method is presented to handle the problem of competing convention while training an ANN by using a GA. This technique is applied to calculate the resonant frequency of a thick-substrate rectangular microstrip antenna (RMA). The training time is less than that of a normal feed-forward backpropagation algorithm. The measured results are in very good agreement with experimental results.

Microwave and Optical Technology Letters, 2006

The resonance frequency of an E-shaped microstrip antenna has been calculated by equating its are... more The resonance frequency of an E-shaped microstrip antenna has been calculated by equating its area to an equivalent area of a rectangular microstrip patch antenna. A new expression for effective dielectric constant is developed for the E-shaped microstrip patch antenna. The new expression of resonance frequency is used to calculate the results, which are in good agreement with the measured and published results.

Microbiological Research, 2010

We have done a comparative study of tRNA diversity and total tRNA genes among different strains o... more We have done a comparative study of tRNA diversity and total tRNA genes among different strains of bacteria with respect to the optimum growth temperature of the cells. Our observation suggests that higher tRNA diversity usually occurs in thermophiles in comparison to non-thermophiles. Among psychrophiles total tRNA was observed to be more than twofold higher than in the non-psychrophiles. Though tRNA diversity and total tRNA have recently been shown to be affected by an organism's genomic GC% and growth rate, this work is the first report on growth temperature affecting these features in bacteria. This work extends the list of molecular features undergoing adaptation due to growth temperature and supports the view that growth temperature acts as a selecting factor at the molecular level during evolution.