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Selvan S.,Francis Xavier Engineering College | Nataraj R.V.,PSG College of Technology
IEEE Transactions on Knowledge and Data Engineering | Year: 2010

In this paper, we address the problem of mining large maximal bicliques from a three-dimensional Boolean symmetric adjacency matrix. We propose CubeMiner-MBC algorithm which enumerates all the maximal bicliques satisfying the user-specified size constraints. Our algorithm enumerates all bicliques with less memory in depth first manner and does not store the previously computed patterns in the main memory for duplicate detection. To efficiently prune duplicate patterns, we have proposed a subtree pruning technique which reduces the total number of nodes that are processed and also reduces the total number of duplicate patterns that are generated. We have also incorporated several optimizations for efficient cutter generation and closure checking. Experiments involving several synthetic data sets show that our algorithm takes less running time than CubeMiner algorithm. © 2006 IEEE.

Masilamani S.,KS Rangasamy College of Technology | Musthafa A.M.,Francis Xavier Engineering College
Microchemical Journal | Year: 2013

In recent times semiorganic nonlinear optical material is a forefront of current research because of its importance to providing key functions of frequency conversion, light modulations and optical memory storage. Most of the organic materials have inadequate transparency, poor optical quality and low laser damage threshold. Inorganic materials have excellent mechanical and thermal properties but they possess relatively modest nonlinearity. Semiorganic materials which have combined properties of both organic and inorganic materials. In this coordination complex the organic ligand plays an important role for the nonlinear optical property. Nowadays, amino acids are more suitable organic materials for nonlinear optical applications because they contain dipolar nature due to the presence of a protonated amino group (NH3 +) and deprotonated carboxylic group (COO-). In the present study l-asparagine lithium chloride (LALC) was grown from aqueous solution by slow evaporation method. The crystalline perfection of the material was confirmed by powder X-ray diffraction. The lattice parameters were calculated by single crystal X-ray diffraction and it was found to be the LALC crystallized in orthorhombic crystal system with noncentro symmetric space group of Pna21 which is one of the essential parameters in nonlinear optical materials. The optical transparency was analyzed by UV-vis transmission spectral study and it was found to be of lower cut off wavelength of the grown crystal which is 234nm. The presence of functional groups was identified by FTIR spectral analysis. The percentage of carbon, hydrogen and nitrogen in the crystal was calculated by chemical analysis and compared with its theoretical values. The mechanical strength was calculated by Vickers microhardness tester. The nonlinear optical efficiency of the crystal was estimated by using Kurtz Perry powder technique and it was found to be 2.08 times that of potassium dihydrogen phosphate (KDP) due to noncentro symmetric space group of good nonlinear optical material. Hence, LALC crystal is more suitable for the fabrication of optoelectronic devices. © 2013 Elsevier B.V.

Narayanamoorthy R.,Francis Xavier Engineering College | Huzur Saran V.,Indian Institute of Technology Roorkee
International Journal of Industrial Ergonomics | Year: 2012

The present study investigated effects of vibration direction, vibration magnitude, object size, object distance and angle of approach on movement time taken by eleven participants using a mouse to perform 'pointing and clicking' activity on a laptop. From the combination of vibration directions, vibration magnitudes, object sizes, object distances and angles of approach, a total of 416 exposure conditions were considered. For successful completion of 'pointing and clicking' activity under different exposure conditions, the time required to finish the task was measured. Using the Fitts' law, a relation between movement time and index of difficulty was developed for different vibration directions and magnitudes considered in the study. Higher vibration magnitudes, smaller size of the objects, and diagonal angular movements were found to affect the movement time and hence showed difficulties to perform the activity. Relevance to industry: This study investigated the performance of a mouse to execute pointing and clicking activity on a laptop in vibration environment. The results showed that difficulties to perform the activity were due to higher magnitudes, smaller size of the objects, and diagonal cursor movements. These research achievements can help human-computer interaction design in various dynamic environments such as in land and sea vehicles. © 2012 Elsevier B.V.

Ratna S.R.,Francis Xavier Engineering College | Ravi R.,Francis Xavier Engineering College
Cluster Computing | Year: 2016

The open nature of communication medium in wireless networks becomes easy for the attackers to indulge in jamming attack. Jamming blocks the communication channel with the intent of preventing the flow of useful information. Jammers effectively and stealthy corrupts the packet by injecting high level of noise thereby keeping the channel busy so that the legitimate traffic gets completely blocked, resulting in packet loss at the receiver side. Securing the information from the jammers has become very important. Therefore an effective approach is needed to prevent this attack and this paper proposes Discriminate based Misbehavior Prevention DMP scheme to identify and to detach the jammer that corrupts the packet in wireless network. The proposed scheme consists of three modules. In module one, the log files are analyzed and using the trusting mechanism the suspected traces are identified. In module two, three reshuffling algorithms has been developed for reshuffling and identifying doubtful traces. In module three, the jammer nodes are identified and detached from the network. By simulation studies, it is observed that the proposed scheme attains higher throughput and packet delivery ratio while attaining lower delay. © 2016 Springer Science+Business Media New York

Narayanamoorthy R.,Francis Xavier Engineering College | Huzur Saran V.,Indian Institute of Technology Roorkee
Computers in Human Behavior | Year: 2011

The present study investigates influences of vibration directions, vibration magnitudes, object sizes, object distances and angles of approach on producing errors while performing pointing and clicking activity on a laptop monitor similar to passengers working on moving trains. Attempts made outside the boundary of an object while performing the activity is registered as an error. The number of errors produced under different exposure conditions is computed. Higher vibration magnitudes, smaller size of the objects, and diagonal angular movements are found to create more errors and affected accuracy of the activity and hence showed difficulties to perform the activity. © 2011 Elsevier Ltd. All rights reserved.

Vinu J.,Francis Xavier Engineering College | Anto Theepak T.,Francis Xavier Engineering College
2012 International Conference on Computing, Electronics and Electrical Technologies, ICCEET 2012 | Year: 2012

Today's attack scenery is governed by Botnets. Botnet refers to a group of bots - a sort of malware which allows an attacker to achieve complete control over the affected computer. Botnets are often run by malicious programmers with specific skills. This work is to understand the consequence of large-scale "botnet probes" through investigating the ways to analyze collections of malicious probing traffic. In such events, a whole collection of remote hosts together probes the address space monitored by a sensor in somewhat a synchronized fashion. The goal is to extend methodologies by which sites receiving such probes can understand using purely local surveillance i.e., information about the probing activity regarding scanning strategies the probing employ and whether the attack specifically targets the site, or the site just accidentally probed as part of a larger, unselective attack? Our analysis draws upon comprehensive honeynet data to discover the occurrence of diverse types of scanning, with properties such as trend, uniformity, coordination, and darknet avoidance. Cross-evaluating with data from DShield assures that this approach holds for contributing to a site's "realization" accurately. © 2012 IEEE.

Muthukumaran N.,Francis Xavier Engineering College | Ravi R.,Francis Xavier Engineering College
Wireless Personal Communications | Year: 2016

In this research paper, a high throughput memory efficient pipelining architecture for Fast Efficient Set Partitioning in Hierarchical Trees (SPIHT) image compression system is explained. The main aim of this paper is to compress and implement the image without any loss of information. So, we are using spatial oriented tree approach in Fast Efficient SPIHT algorithm for compression and Spartan 3 EDK kit for hardware implementation analysis purpose. Integer wavelet transform is used for encoding and decoding process in SPIHT algorithm. Here, we are using pipelining architecture to implement it in FPGA kit because pipeline architecture is more suitable for hardware utility purpose. Generally an image file will occupy more amount of space. In order to reduce the memory size no loss during transmission we are using this approach. By this way we are attained maximum PSNR value, CR and also produced very high accurate image after decompression, when compared with the results of other previous algorithms. In this module, the hardware tools used are dual core processor and FPGA Spartan 3 EDK kit and the software tool windows 8 operating system and the tool kit is MATLAB 7.8. © 2016, Springer Science+Business Media New York.

Johncy Vijayakumari V.,Francis Xavier Engineering College
2011 International Conference on Emerging Trends in Electrical and Computer Technology, ICETECT 2011 | Year: 2011

Transparent optical networks based on wavelength division multiplexing (WDM) can exploit the huge capacity of optical fibers by dividing it among different wavelengths. Physical-layer attacks, such as high-powered jamming, can seriously degrade network performance and must be dealt with efficiently. Hence route lightpaths in such a way as to minimize the potential damage caused by various physical-layer attacks. A new objective criterion for the routing and wavelength assignment (RWA) problem, which we call the maximum Lightpath Attack Radius (maxLAR) is used to formulate the routing subproblem as an integer linear program (ILP). Lightpaths, are established between pairs of nodes. Given a physical topology and a set of lightpath demands, the RWA problem consists of finding a physical route for each lightpath demand and assigning to each route a wavelength, subject to the constraints. The maxLAR is the maximum number of lightpaths any one lightpath is link-sharing with, where link-sharing is defined as a property indicating whether two lightpaths traverse at least one common physical link. Results indicate that the formulation achieves significantly better results for the maxLAR. For larger networks, a tabu search algorithm for attack-aware lightpath routing, in combination with an existing graph-coloring algorithm for wavelength assignment is used. Testing and comparing with existing approaches from literature indicate its superiority with respect to the maxLAR and thus the congestion is reduced effectively. © 2011 IEEE.

Hansen R.S.,Francis Xavier Engineering College | Narayanan C.S.,National Engineering College | Murugavel K.K.,National Engineering College
Desalination | Year: 2015

In this paper the performance of an inclined type solar still was experimentally investigated using different wick materials on different absorber plate configurations. In this work, the new materials are characterised for absorption, capillary rise, porosity, water repellence and heat transfer co-efficient to select a suitable material for the solar desalination application. Different wick materials are chosen for this analysis. Based on this analysis, water coral fleece material with porosity (69.67%), absorbency (2s), capillary rise (10mm/h) and heat transfer coefficient (34.21W/m2°C) is the most suitable wicking material for higher productive solar still. Performances of the still were compared with different wick materials (wood pulp paper wick, wicking water coral fleece fabric and polystyrene sponge) on the various absorber plate configurations (flat absorber, stepped absorber and stepped absorber with wire mesh). Maximum distillate achieved in the still was 4.28l/day by using water coral fleece with weir mesh-stepped absorber plate. © 2014 Elsevier B.V.

Jenifer P.,Francis Xavier Engineering College
2011 International Conference on Emerging Trends in Electrical and Computer Technology, ICETECT 2011 | Year: 2011

The objective is to develop a probabilistic approach for vision-based fire detection in videos. The proposed method analyzes the frame-to-frame changes of specific low-level features describing potential fire regions. These features are color, area size, surface coarseness, boundary roughness, and skewness within estimated fire regions. Because of flickering and random characteristics of fire, these features are powerful discriminants. The behavioral change of each one of these features is evaluated, and the results are then combined according to the Bayes classifier for robust fire recognition. Temporal matching concept is used to reduce the computational complexity and also to allow fast processing of videos. Early vision-based fire detection techniques target surveillance applications with static cameras and consequently reasonably controlled or static background. In contrast, the proposed method can be applied not only to surveillance but also to automatic video classification for retrieval of fire catastrophes in databases of newscast content. © 2011 IEEE.

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