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Aloke Dey

Bio: Aloke Dey is an academic researcher. The author has contributed to research in topics: Block (telecommunications). The author has an hindex of 1, co-authored 1 publications receiving 78 citations.

Papers
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Book
01 Jan 1986
TL;DR: Introduction Some Mathematical and Statistical Results General Properties of Block Designs Balanced Incomplete Block Designs - Properties and Analysis Construction and Existence of Balanced In complete Block Designs Partially Balanced In Complete Block Designs Additional Topics in Block Designs Index.
Abstract: Introduction Some Mathematical and Statistical Results General Properties of Block Designs Balanced Incomplete Block Designs - Properties and Analysis Construction and Existence of Balanced Incomplete Block Designs Partially Balanced Incomplete Block Designs Additional Topics in Block Designs Index.

79 citations


Cited by
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Journal ArticleDOI
TL;DR: The average cost, due to call loss and location updates using such systems, is analyzed in the presence of database disconnections and the tradeoff between the system reliability and the cost of location updates in the UQS scheme is investigated.
Abstract: A distributed mobility management scheme using a class of uniform quorum systems (UQS) is proposed for ad hoc networks. In the proposed scheme, location databases are stored in the network nodes themselves, which form a self-organizing virtual backbone within the flat network structure. The databases are dynamically organized into quorums, every two of which intersect at a constant number of databases. Upon location update or call arrival, a mobile's location information is written to or read from all the databases of a quorum, chosen in a nondeterministic manner. Compared with a conventional scheme [such as the use of home location register (HLR)] with fixed associations, this scheme is more suitable for ad hoc networks, where the connectivity of the nodes with the rest of the network can be intermittent and sporadic and the databases are relatively unstable. We introduce UQS, where the size of the quorum intersection is a design parameter that can be tuned to adapt to the traffic and mobility patterns of the network nodes. We propose the construction of UQS through the balanced incomplete block designs. The average cost, due to call loss and location updates using such systems, is analyzed in the presence of database disconnections. Based on the average cost, we investigate the tradeoff between the system reliability and the cost of location updates in the UQS scheme. The problem of optimizing the quorum size under different network traffic and mobility patterns is treated numerically. A dynamic and distributed HLR scheme, as a limiting case of the UQS, is also analyzed and shown to be suboptimal in general. It is also shown that partitioning of the network is sometimes necessary to reduce the cost of mobility management.

291 citations

Journal ArticleDOI
TL;DR: By further discriminating the pairwise correlations, efficient designs of runs from 6 to 24 are constructed and tabulated, demonstrating the effectiveness of the general algorithm of constructing E(s2) optimal supersaturated designs from cyclic BIBDs.

89 citations

Journal ArticleDOI
TL;DR: The upper bounds are obtained by applying the linear programming bound to the product of two association schemes and the lower bounds arise from a number of different constructions.
Abstract: Upper and lower bounds are presented for the maximal possible size of mixed binary/ternary error-correcting codes. A table up to length 13 is included. The upper bounds are obtained by applying the linear programming bound to the product of two association schemes. The lower bounds arise from a number of different constructions.

87 citations

Proceedings ArticleDOI
06 Jun 1999
TL;DR: Numerical results show that the RDG scheme provides a robust and efficient approach to ad-hoc mobility management, and the numerical determination and approximation of the optimal total location database number, the optimal database access group size and the optimal location update frequency, under different network stability, traffic, and mobility conditions.
Abstract: A distributed mobility management scheme using randomized database groups (RDG) is proposed and analyzed for ad-hoc networks. In the proposed scheme, location databases are stored in the network nodes, comprising a virtual backbone within the flat network architecture. Upon location update or call arrival, a mobile's location information is written to or read from, respectively, a group of randomly chosen databases. Compared with a centralized scheme (such as the home location register) with fixed associations, this scheme is more suitable for ad-hoc networks, where the connectivity of the nodes with the rest of the network can be intermittent and sporadic, and the databases are relatively unstable. The expected cost due to call loss and location updates using this scheme is analyzed in the presence of database disconnections. Based on the expected cost, we present the numerical determination and approximation of the optimal total location database number, the optimal database access group size, and the optimal location update frequency, under different network stability, traffic, and mobility conditions. Numerical results show that the RDG scheme provides an robust and efficient approach to ad-hoc mobility management.

65 citations

Book
01 Jan 2000
TL;DR: In this article, the authors introduce vector spaces and matrices, linear estimation, tests of linear hypothesis, Singular values and their applications, block designs and optimization, and rank additivity.
Abstract: Vector Spaces and Matrices.- Linear Estimation.- Tests of Linear Hypotheses.- Singular Values and Their Applications.- Block Designs and Optimality.- Rank Additivity.

59 citations