Browsing by Author "Chandra Sekaran, K.C."

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A multiobjective phenomic algorithm for inference of gene networks
(2012) D'Souza, R.G.L.; Chandra Sekaran, K.C.; Kandasamy, A.
Reconstruction of gene networks has become an important activity in Systems Biology. The potential for better methods of drug discovery and of disease diagnosis hinge upon our understanding of the interaction networks between the genes. Evolutionary methods are proving to be successful in such problems and a number of such methods have been proposed. However, all these methods are based on processing of genotypic information. We have presented an evolutionary algorithm for reconstructing gene networks from expression data using phenotypic interactions, thereby avoiding the need for an explicit objective function. Specifically, we have also extended the basic phenomic algorithm to perform multiobjective optimization for gene network reconstruction. We have applied this novel algorithm to the yeast sporulation dataset and validated it by comparing the results to the links found between genes of the yeast genome at the SGD database. Â© 2012 ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering.
A phenomic algorithm for inference of gene networks using S-systems and memetic search
(2012) D'Souza G, R.G.L.; Chandra Sekaran, K.C.; Kandasamy, A.
In recent years, evolutionary methods have seen unprecedented success in elucidation of gene networks, especially from microarray data. We have implemented the Phenomic Algorithm which is an evolutionary method for inference of gene networks based on population dynamics. We have used S-systems to model gene interactions and applied memetic search to fine tune the parameters of the inferred networks. We have tested the novel algorithm on artificial gene expression datasets obtained from simulated gene networks. We have also compared the results to those obtained from two other similar algorithms. Results showed that the new method, which we call as Phenomic Algorithm with Memetic Search (PAMS), is an effective method for inference of gene networks. Â© 2012 ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering.
A phenomic approach to genetic algorithms for reconstruction of gene networks
(2010) D'Souza, R.G.L.; Chandra Sekaran, K.C.; Kandasamy, A.
Genetic algorithms require a fitness function to evaluate individuals in a population. The fitness function essentially captures the dependence of the phenotype on the genotype. In the Phenomic approach we represent the phenotype of each individual in a simulated environment where phenotypic interactions are enforced. In reconstruction type of problems, the model is reconstructed from the data that maps the input to the output. In the phenomic algorithm, we use this data to replace the fitness function. Thus we achieve survival-of-the- fittest without the need for a fitness function. Though limited to reconstruction type problems where such mapping data is available, this novel approach nonetheless overcomes the daunting task of providing the elusive fitness function, which has been a stumbling block so far to the widespread use of genetic algorithms. We present an algorithm called Integrated Pheneto-Genetic Algorithm (IPGA), wherein the genetic algorithm is used to process genotypic information and the phenomic algorithm is used to process phenotypic information, thereby providing a holistic approach which completes the evolutionary cycle. We apply this novel evolutionary algorithm to the problem of elucidation of gene networks from microarray data. The algorithm performs well and provides stable and accurate results when compared to some other existing algorithms. Â© 2010 Springer-Verlag Berlin Heidelberg.
Active probing based end to end internet path metrics estimation tool
(2006) Suryanarayana, V.; Chandra Sekaran, K.C.
This paper considers the problem of measuring the various network path metrics such as Connectivity, Capacity, bandwidth, available bandwidth etc. of a network path using probing-based methods. To that end, we propose a new model called an Integrated Metrics Measurement Model (IMMM) to measure all possible performance metrics. It will be designed to probe the network non-intrusively so that the measurements will not disturb the stability of the network. The experimental results of our partial implementation of the proposed model are presented. Â© 2006 IEEE.
Autonomic computing: A fuzzy control approach towards application development
(IGI Global, 2011) Harish, H.S.; Chandra Sekaran, K.C.
Autonomic computing (Salehie & Tahvildari, 2005) is a new paradigm to design, develop, deploy, and manage systems by taking inspiration from strategies used by biological systems. An autonomic system has four major characteristics: self-configure, self-heal, self-optimize, and self-protect. The autonomic computing architecture provides a blueprint for developing feedback control loops for self-managing systems. This observation suggests that control theory might provide guidance as to the structure of and requirements for autonomic managers. E-commerce is an area where an Autonomic Computing system could be very effectively deployed. E-commerce has created demand for high quality information technology services, and businesses seek ways to improve the quality of service in a cost-effective way. Properly adjusting tuning parameters for best values is time-consuming and skills-intensive. This chapter describes simulation environments to implement approaches to automate the tuning of MaxClients parameter of Apache web server using fuzzy controllers. These are illustrations of the self-optimizing characteristic of an autonomic computing system. © 2012, IGI Global.
Autonomous data replication using Q-learning for unstructured P2P networks
(2007) Thampi, S.M.; Chandra Sekaran, K.C.
Resource discovery is an important problem in unstructured peer-to-peer networks as there is no centralized index where to search for information about resources. The solution for the problem is to use a search algorithm that locates the resources based on the local information about the network. Efficient data sharing in a peer-to-peer system is complicated by uneven node failure, unreliable network connectivity and limited bandwidth. A well-known technique for improving availability is replication. If multiple copies of data exist on independent nodes, then the chances of at least one copy being accessible are increased. Replication increases robustness. In this paper, we present a novel technique based on Q-learning for replicating objects to other nodes. Â© 2007 IEEE.
Cloud workflow and security: A survey
(Institute of Electrical and Electronics Engineers Inc., 2014) Anupa, J.; Chandra Sekaran, K.C.
The cloud revolution has helped enterprises to improve their business and performance by providing them computing power, storage capabilities and a variety of services for very less or no infrastructure and reasonable cost. It also provisioned the scientific and academic communities to run complex applications involving large data sets, high performance or distributed resources. The Workflow Management Systems (WfMSs) help the enterprises in automation of their business processes and thus help the management to take critical decisions fast. Cloud Workflows club the advantages of both Cloud Computing and WfMSs. In spite of the advantages of the cloud, security is a major area of concern. The use of WfMSs for critical and strategic applications, which is common in case of Business and Scientific community, gives rise to major concerns regarding the threats against integrity, authorization, availability etc. The concept of running secure workflow instances on public cloud processing platforms is still in its infancy. This paper gives an overview of workflow management systems, cloud computing, cloud workflows and security in these areas. This paper also provides a survey on security mechanisms for WfMSs and Cloud Workflows. Â© 2014 IEEE.
Design and development of proactive solutions for mitigating denial-of-service attacks
(2006) Nagesh, H.R.; Chandra Sekaran, K.C.
Denial of Service attacks, orchestrated by a single host or multiple hosts in a coordinated manner, has become an increasingly frequent disturbance in today's Internet. Generally, attackers launch DDoS attacks by directing a massive number of attack sources to send useless traffic to the victim. The victim's services are disrupted when its host or network resources are occupied by the attack traffic. The threat of DDoS attacks has become even more severe as attackers can compromise a huge number of computers using vulnerabilities in popular operating systems [4].This paper deals with Denial of service (DoS) and Distributed DoS (DDoS) attacks. In the first part, we categorize existing defense mechanisms, and analyze their strengths and weaknesses. In the second part of our investigation, we develop and evaluate two defense models for DoS attacks: the Secure Overlay Services (SOS) Model and the Server Hopping Model using distributed firewalls. Each of these models provide defense in a different part of the network, and has different resource requirements. In the third part of our investigation, we assess the effectiveness of our defense models for different types of DoS attack. Â© 2006 IEEE.
Detection of reticulation events - A character based method
(2006) Navada, K.C.; Chandra Sekaran, K.C.
It is observed that during the evolution of species, reticulation is an important event and is very prevalent in several organisms. However, the analytical tools for the representation of these events are still under development. This is primarily because of the difficulty involved in detecting these reticulation events that have taken place during the evolution using the sequences that are currently available in some form. Since it is not possible to get each sequence starting from the root (beginning of the evolution process), inferring the history has to be based on a few assumptions, which are biologically valid. In this paper, we propose an algorithm which, we feel, is a step in this direction. The algorithm detects the sequences which require reticulation events for their formation and returns the count of such sequences. Â© 2006 IEEE.
Developing a conceptual relationship between web service supply chain entities
(2011) Venkatraman, V.; Chandra Sekaran, K.C.; Arshinder, A.; Rajendran, C.
Globalization has led to a new class of service apart from the services that are offered offline and semionline (in which case part of the service transactions are online and part of it offline) as a result of collaboration of static entities resulting in static service supply chains. The advent of enablers like Service Oriented Architecture and development of web service applications has enabled online / dynamic service supply chain networks (SSCNs) formed by dynamic collaboration of many serving entities. The entities in web SSCNs are interdependent and the performance of one entity impacts the performance of other entities as well as overall performance of service network. It is important to study the relationship and dependency between each entity of web SSCNs. Once the relationship is identified, it will help in devising some composite performance indicator for the entire service supply chain considering the interests of service providers and clients. We take a scenario based illustration of such online service supply chains to show the feasibility of the conceptÂ© 2011 IEEE.
Development of a link layer protocol using UML
(Institute of Electrical and Electronics Engineers Inc., 2001) Chandra Sekaran, K.C.
This paper presents a report on the development of a link layer protocol using an object oriented formal method. It describes the steps involved in the conceptualization, analysis and design of the L2CAP (Logical Link Control and Adaptation Layer Protocol) of the Bluetooth architecture. UML (Unified Modeling Language) is the formal modeling language used in this work. It has been shown how the static, dynamic and operational aspects of the system are captured using various UML diagrams. Â© 2001 IEEE.
Distributed multi level security token based authentication for ubiquitous objects -DMSA
(2006) Kulkarni, U.P.; Vadavi, J.V.; Joshi, S.M.; Chandra Sekaran, K.C.; Yardi, A.R.
Ubiquitous computing technology provides an environment where users expect to access resources and services anytime and anywhere. The serious security risks and problems arise because resources can now be accessed by almost anyone with a mobile device in such an open model. This paper explores security in ubiquitous computing with focus on authentication. We propose a new model, which uses distributed hierarchical tree based approach for authenticating ubiquitous objects which overcomes the problems associated with centralized source of information. Â© 2006 IEEE.
Executable specification and prototyping of network protocols using UML and Java
(2009) Chandra Sekaran, K.C.; Gnanamurthy, R.K.
Network protocols are often implemented in software and / or hardware, and, it becomes essential to design and test them in an efficient manner. This paper explores a dual phase approach for developing network protocols: in the first phase protocols are modeled using UML (Unified Modeling Language) as the formalism, and, in the second phase, use of executable specification and prototyping of protocols based on Java is supported. The prototyping of a protocol is useful for further investigations such as verification ofprotocol properties, test case generation etc. Once the second phase provides a satisfied result, the developers can go ahead in developing and deploying the protocol in the real environment. Yet another objective in this work is to design executable constructs in Java to specify protocols and prototyping them. The protocols designed using this approach ensures sustenance of the models already developed. Illustration of using executable constructs in Java to specify and prototyping ofprotocols, and comparison with native implementations is presented in this paper. Â©2009 IEEE.
Floating-point adder in techology driven high-level synthesis
(2011) Joseph, M.; Bhat Narasimha, N.B.; Chandra Sekaran, K.C.
Implementation of floating-point algorithms in fixedpoint processor asks for customization into fixed-point for that processor. Technology driven High-Level Synthesis is a customized High-Level Synthesis approach for a particular fixed-point processor. It makes the present High-Level Synthesis knowledgeable of the target Field Programmable Gate Array. All the functions of High-Level Synthesis become aware of target technology since parsing here. It makes right inference of hardware by attaching target technology specific attributes to the parse tree in it, which guides to generate optimized hardware. This paper, integrating both, presents an approach to synthesize the floating-point algorithms in this customized tool. It performs the conversion of floating-point model into corresponding fixed-point model and synthesizes it for implementing onto an Field Programmable Gate Array. This compiler driven approach generates optimal output in terms of silicon usage and power consumption. Â© Springer-Verlag Berlin Heidelberg 2011.
Game theoretic approaches for job scheduling in cloud computing: A survey
(Institute of Electrical and Electronics Engineers Inc., 2015) Ananth, A.; Chandra Sekaran, K.C.
Cloud computing is one of the promising technology in current day scenario. Job scheduling in cloud environment is an important issue where the main aim is to schedule the jobs appropriately in order to effectively utilize the resources and also meet the user's satisfaction. Cloud provider has to consider various aspects like number of cloud users requesting for a service at the same time, availability of resources at that time, Service Level Agreements (SLAs), Quality of Service (QoS) requirements, etc. There are various approaches for scheduling the jobs. In this paper we focus on game theory based approaches for job scheduling in cloud. Survey of existing approaches and various issues in game theory based job scheduling is the main objective of this paper. We study the existing approaches for job scheduling focusing game theoretic approaches and analyze the open issues for research in this area. Â© 2014 IEEE.
Implementation of an adaptive buffering algorithm to improve QoS in VoIP
(2005) Nagesh, H.R.; Chandra Sekaran, K.C.; Kordcal, A.R.
The Internet has evolved into a worldwide communication infrastructure and it now provides various services including Voice over IP (VoIP) or Internet Telephony [7]. VoIP involves transmission of voice packets across the IP network known as IP telephony. Internet Protocol (IP) Telephony has many issues that have to be overcome before it can be considered a rival to the existing telephony infrastructure. One such issue is the Quality of service (QoS). The use of play-out buffering at the receiver helps to improve the quality of Voice over IP (VoIP). There exists a buffering algorithm, which uses a dynamic adaptive approach. In this algorithm the playout times of voice packets are calculated using adaptive estimation of the network delays. In contrast to previous solutions, weighting factor that controls the estimation process is dynamically adjusted according to the observed delay variations. This results in higher quality estimates of network delay. The contribution of this paper is to analyze, implement and incorporate one such adaptive buffering algorithm into the Session Initiation Protocol (SIP) through which one can achieve better delay/loss trade-off and thus better call quality.
Inference of Gene Networks from Microarray Data through a Phenomic Approach
(2010) D'Souza, R.G.L.; Chandra Sekaran, K.C.; Kandasamy, A.
The reconstruction of gene networks is crucial to the understanding of cellular processes which are studied in Systems Biology. The success of computational methods of drug discovery and disease diagnosis is dependent upon our understanding of the biological basis of the interaction networks between the genes. Better modelling of biological processes and powerful evolutionary methods are proving to be a key factor in the solution of such problems. However, most of these methods are based on processing of genotypic information. We present an evolutionary algorithm for inferring gene networks from expression data using phenotypic interactions. The benefit of this is that we avoid the need for an explicit objective function in the optimization process. In order to realize this, we have implemented a method called as the Phenomic algorithm and validated it for stability and accuracy in the reconstruction of gene networks. Â© Springer-Verlag Berlin Heidelberg 2010.
Intrusion detection as a service (IDaaS) in an open source cloud infrastructure
(2013) Veigas, J.P.; Chandra Sekaran, K.C.
[No abstract available]
Memetic NSGA - A multi-objective genetic algorithm for classification of microarray data
(Institute of Electrical and Electronics Engineers Inc., 2007) Kumar K, P.; Sharath, S.; D'Souza G, R.; Chandra Sekaran, K.C.
In Gene Expression studies, the identification of gene subsets responsible for classifying available samples to two or more classes is an important task. One major difficulty in identifying these gene subsets is the availability of only a few samples compared to the number of genes in the samples. Here we treat this problem as a Multi-objective optimization problem of minimizing the gene subset size and minimizing the number ofmisclassified samples. We present a new elitist Non-dominated Sorting-based Genetic Algorithm (NSGA) called Memetic-NSGA which uses the concept of Memes. Memes are a group of genes which have a particular functionality at the phenotype level. We have chosen a 50 gene Leukemia dataset to evaluate our algorithm. A comparative study between Memetic-NSGA and another Non-dominated Sorting Genetic Algorithm, called NSGA-II, is presented. Memetic-NSGA is found to perform better in terms of execution time and gene-subset length identified. Â© 2007 IEEE.
Minimizing response time in an autonomic computing system using proportional control
(2010) Harish, H.S.; Chandra Sekaran, K.C.
Ecommerce is an area where an Autonomic Computing system could be very effectively deployed. Ecommerce has created demand for high quality information technology services and businesses are seeking quality of service guarantees from their service providers. These guarantees are expressed as part of service level agreements. Properly adjusting tuning parameters for enforcement of the service level agreement is time-consuming and skills-intensive. Moreover, in case of changes to the workload, the setting of the parameters may no longer be optimum. In an ecommerce system, where the workload changes frequently, there is a need to update the parameters at regular intervals. This paper describes an approach to automate the tuning of MaxClients parameter of Apache web server using a proportional controller based on the required response time and the current workload. This is an illustration of the self-optimizing characteristic of an autonomic computing system. Â© 2010 Springer-Verlag Berlin Heidelberg.