Статьи журнала - International Journal of Information Technology and Computer Science

Все статьи: 811

32Still Image Compression Algorithm Based on Directional Filter Banks

32Still Image Compression Algorithm Based on Directional Filter Banks

Chunling Yang, Duanwu Cao, Li Ma

Статья научная

Hybrid wavelet and directional filter banks (HWD) is an effective multi-scale geometrical analysis method. Compared to wavelet transform, it can better capture the directional information of images. But the ringing artifact, which is caused by the coefficient quantization in transform domain, is the biggest drawback of image compression algorithms in HWD domain. In this paper, by researching on the relationship between directional decomposition and ringing artifact, an improved decomposition approach of HWD(IHWD) is roposed to reduce the ringing artifact. In addition, the IHWD algorithm and directional weighting model is applied into the JPEG2000 coding framework, and a new still magecompression algorithm IJPEG2000 is proposed. The experimental results show that IJPEG2000 has better performance than JPEG2000 whether on objective evaluation method or on subjective visual feeling.

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A Clientless Endpoint Authentication SchemeBased on TNC

A Clientless Endpoint Authentication SchemeBased on TNC

Kun Wu, Zhongying Bai

Статья научная

Trusted Network Connect (TNC) proposes a hierarchical and scalable architecture to securely and efficiently control endpoints` admission to the trusted computing platform to implement message passing and resource sharing. But, not all endpoints support or run a functional TNC client performing integrity checking, which represents a security risk in lots of environments. We have to consider the problem how to make these "clientless endpoints" access to trusted networks. It is of significance for improving the TNC mechanism. To solve the problem above, under the framework of TNC, this paper comes up with a clientless endpoint authentication scheme named CEAS. CEAS designs five enforcement mechanisms and the related message format to authenticate and authorize clientless endpoints. Furthermore, after the endpoints have connected to the networks, their initial determinations may be dynamically modified according to the updated circumstances. The experiment results prove that CEAS has the capability of effectively and flexibly making clientless endpoints access to trusted networks in a controlled and secure manner.

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A Cluster Based Job Scheduling Algorithm for Grid Computing

A Cluster Based Job Scheduling Algorithm for Grid Computing

Reza Fotohi, Mehdi Effatparvar

Статья научная

Grid computing enables sharing, selection and aggregation of computing resources for solving complex and large-scale scientific problems. The resources making up a grid need to be managed to provide a good quality of service. Grid scheduling is a vital component of a Computational Grid infrastructure. This paper presents a dynamic cluster based job scheduling algorithm for efficient execution of user jobs. This paper also includes the comparative performance analysis of our proposed job scheduling algorithm along with other well-known job scheduling algorithms considering the parameters like average waiting time, average turnaround time, average response time and average total completion time. The result has shown also exhibit that Our proposed scheduling algorithms (CHS ) has shown the best average waiting times, average turnaround times, average response times and average total completion times compared to other job scheduling approaches.

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A Clustering-based Offline Signature Verification System for Managing Lecture Attendance

A Clustering-based Offline Signature Verification System for Managing Lecture Attendance

Laruba Adama, Hamza O. Salami

Статья научная

Attendance management in the classroom is important because in many educational institutions, sufficient number of class attendance is a requirement for earning a regular grade in a course. Automatic signature verification is an active research area from both scientific and commercial points of view as signatures are the most legally and socially acceptable means of identification and authorization of an individual. Different approaches have been developed to achieve accurate verification of signatures. This paper proposes a novel automatic lecture attendance verification system based on unsupervised learning. Here, lecture attendance verification is addressed as an offline signature verification problem since signatures are recorded offline on lecture attendance sheets. The system involved three major phases: preprocessing, feature extraction and verification phases. In the feature extraction phase, a novel set of features based on distribution of black pixels along columns of signatures images is also proposed. A mean square error of 0.96 was achieved when the system was used to predict the number of times students attended lectures for a given course.

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A Comparative Performance Analysis of Low Power Bypassing Array Multipliers

A Comparative Performance Analysis of Low Power Bypassing Array Multipliers

Nirlakalla Ravi, S. Venkateswarlu, T. Jayachandra Prasad, Thota Subba Rao

Статья научная

Low power design of VLSI circuits has been identified as vital technology in battery powered portable electronic devices and signal processing applications such as Digital Signal Processors (DSP). Multiplier has an important role in the DSPs. Without degrading the performance of the processor, low power parallel multipliers are needed to be design. Bypassing is the widely used technique in the DSPs when the input operand of the multiplier is zero. A Row based Bypassing Multiplier with compressor at the final addition of the ripple carry adder (RCA) is designed to focus on low power and high speed. The proposed bypassing multiplier with compressor shows high performance and energy efficiency than Kuo multiplier with Carry Save Adder (CSA) at the final RCA.

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A Comparative Study on the Performance of Fuzzy Rule Base and Artificial Neural Network towards Classification of Yeast Data

A Comparative Study on the Performance of Fuzzy Rule Base and Artificial Neural Network towards Classification of Yeast Data

Shrayasi Datta, J. Paulchoudhury

Статья научная

Classification of yeast data plays an important role in the formation of medicines and in various chemical components. If the type of yeast can be recognized at the primary stage based on the initial characteristics of it, a lot of technical procedure can be avoided in the preparation of chemical and medical products. In this paper, the performance two classifying methodologies namely artificial neural network and fuzzy rule base has been compared, for the classification of proteins. The objective of this work is to classify the protein using the selected classifying methodology into their respective cellular localization sites based on their amino acid sequences. The yeast dataset has been chosen from UCI machine learning repository which has been used for this purpose. The results have shown that the classification using artificial neural network gives better prediction than that of fuzzy rule base on the basis of average error.

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A Comparison Study on Selective Traffic Models with Handoff Management Scheme for Wireless Mobile Network Infrastructure

A Comparison Study on Selective Traffic Models with Handoff Management Scheme for Wireless Mobile Network Infrastructure

Biswajit Bhowmik

Статья научная

Wireless and Mobile Network Infrastructure services generally examine how different infrastructure providers are positioning themselves to compete in wireless services. These services analyze the opportunities and challenges facing by the infrastructure providers selling to wireless and mobile network operators worldwide. The opportunities and challenges are the review of strategies, market positioning, and future direction in the market for wireless and mobile network infrastructure. The service covers all generations of wireless and mobile network infrastructure: 2G, 2.5G, 3G, and 4G so on global in scope. Majority of the users are mobile while availing these services. Mobility is the most important feature of any wireless and mobile network. Usually, continuous service is achieved by supporting handoff from one cell to another. Poorly designed handoff schemes tend to generate very heavy signaling traffic and, thereby, lead to a dramatic decrease in quality of service. In this paper we make a comparison study on some selective traffic models with priority handoff scheme. The study shows how a handoff procedure has a significant impact on wireless mobile network performance on the basis of two primary criteria – Blocking probability of originating calls and the forced termination probability of ongoing calls. In addition to this the study shows arrival rate of handoff calls, and approximate number of mobile users that get serviced by underlying base station.

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A Comprehensive Survey on Cloud Computing

A Comprehensive Survey on Cloud Computing

Md. Imran Alam, Manjusha Pandey, Siddharth S Rautaray

Статья научная

Cloud Computing is an innovation ideas that helps in reducing the computing cost. Cloud Computing offers better computing through improved utilization and reduced administration and infrastructure costs. Cloud computing is the long-held dream of computing as a utility. Cloud Computing is the combination of Software as a Service (SaaS) and Utility Computing. Cloud computing shares characteristics with autonomic computing, peer to peer, grid computing, client server model, mainframe computer and utility computing. It has various open source resources which gives different platform for better computing utilization. Cloud computing are managed by Cloud Management tools, loaded and tested by various other software testing tools. Cloud computing modelling and simulation is done by CloudSim or SPECI or GroundSim or DCSim on the basis of testing benchmark. The application of Cloud Computing is discussed.

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A Compression & Encryption Algorithm on DNA Sequences Using Dynamic Look up Table and Modified Huffman Techniques

A Compression & Encryption Algorithm on DNA Sequences Using Dynamic Look up Table and Modified Huffman Techniques

Syed Mahamud Hossein, S.Roy

Статья научная

Storing, transmitting and security of DNA sequences are well known research challenge. The problem has got magnified with increasing discovery and availability of DNA sequences. We have represent DNA sequence compression algorithm based on Dynamic Look Up Table (DLUT) and modified Huffman technique. DLUT consists of 43(64) bases that are 64 sub-stings, each sub-string is of 3 bases long. Each sub-string are individually coded by single ASCII code from 33(!) to 96(`) and vice versa. Encode depends on encryption key choose by user from four base pair {a,t.g and c}and decode also require decryption key provide by the encoded user. Decoding must require authenticate input for encode the data. The sub-strings are combined into a Dynamic Look up Table based pre-coding routine. This algorithm is tested on reverse; complement & reverse complement the DNA sequences and also test on artificial DNA sequences of equivalent length. Speed of encryption and security levels are two important measurements for evaluating any encryption system. Due to proliferate of ubiquitous computing system, where digital contents are accessible through resource constraint biological database security concern is very important issue. A lot of research has been made to find an encryption system which can be run effectively in those biological databases. Information security is the most challenging question to protect the data from unauthorized user. The proposed method may protect the data from hackers. It can provide the three tier security, in tier one is ASCII code, in tier two is nucleotide (a,t,g and c) choice by user and tier three is change of label or change of node position in Huffman Tree. Compression of the genome sequences will help to increase the efficiency of their use. The greatest advantage of this algorithm is fast execution, small memory occupation and easy implementation. Since the program to implement the technique have been written originally in the C language, (Windows XP platform, and TC compiler) it is possible to run in other microcomputers with small changes (depending on platform and Compiler used). The execution is quite fast, all the operations are carried out in fraction of seconds, depending on the required task and on the sequence length. The technique can approach an effective compression ratio of 1.98 bits/base and even lower. When a user searches for any sequence for an organism, an encrypted compressed sequence file can be sent from the data source to the user. The encrypted compressed file then can be decrypted & decompressed at the client end resulting in reduced transmission time over the Internet. An encrypt compression algorithm that provides a moderately high compression with encryption rate with minimal decryption with decompression time.

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A Concave Hull Based Algorithm for Object Shape Reconstruction

A Concave Hull Based Algorithm for Object Shape Reconstruction

Zahrah Yahya, Rahmita W Rahmat, Fatimah Khalid, Amir Rizaan, Ahmad Rizal

Статья научная

Hull algorithms are the most efficient and closest methods to be redesigned for connecting vertices for geometric shape reconstruction. The vertices are the input points representing the original object shape. Our objective is to reconstruct the shape and edges but with no information on any pattern, it is challenging to reconstruct the lines to resemble the original shape. By comparing our results to recent concave hull based algorithms, two performance measures were conducted to evaluate the accuracy and time complexity of the proposed method. Besides achieving the most acceptable accuracy which is 100%, the time complexity of the proposed algorithm is evaluated to be O(wn). All results have shown a competitive and more effective algorithm compared to the most efficient similar ones. The algorithm is shown to be able to solve the problems of vertices connection in an efficient way by devising a new approach.

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A Cost-Aware Resource Selection for Dataintensive Applications in Cloud-oriented Data Centers

A Cost-Aware Resource Selection for Dataintensive Applications in Cloud-oriented Data Centers

Wei Liu, Feiyan Shi, Wei Du, Hongfeng Li

Статья научная

As a kind of large-scale user-oriented dataintensive computing, cloud computing allows users to utilize on-demand computation, storage, data and services from around the world in a pay-as-you-go model. In cloud environment, applications need access to mass datasets that may each be replicated on different resources (or data centers). Mass data moving influences the execution efficiency of application to a large extent, while the economic cost of each replica itself can never be overlooked in such a model of business computing. Based on the above two considerations, how to select appropriate data centers for accessing replicas and creating a virtual machine(VM for short) to execute applications to make execution efficiency high and access cost low as far as possible simultaneously is a challenging and urgent problem. In this paper, a cost-aware resource selection model based on Weighted Set Covering Problem (WSCP) is proposed, according to the principle of spatial locality of data access. For the model, we apply a Weighted Greedy heuristic to produce an approximately optimal resource set for each task. Finally, verifies the validity of the model in simulation environment, and evaluate the performance of the algorithm presented. The result shows that WSCP-based heuristic can produce an approximately optimal solution in most cases to meet both execution efficiency and economic demands simultaneously, compared to other two strategies.

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A Data Mining-Based Response Model for Target Selection in Direct Marketing

A Data Mining-Based Response Model for Target Selection in Direct Marketing

Eniafe Festus Ayetiran, Adesesan Barnabas Adeyemo

Статья научная

Identifying customers who are more likely to respond to new product offers is an important issue in direct marketing. In direct marketing, data mining has been used extensively to identify potential customers for a new product (target selection). Using historical purchase data, a predictive response model with data mining techniques was developed to predict a probability that a customer in Ebedi Microfinance bank will respond to a promotion or an offer. To achieve this purpose, a predictive response model using customers’ historical purchase data was built with data mining techniques. The data were stored in a data warehouse to serve as management decision support system. The response model was built from customers’ historic purchases and demographic dataset. Bayesian algorithm precisely Naïve Bayes algorithm was employed in constructing the classifier system. Both filter and wrapper feature selection techniques were employed in determining inputs to the model. The results obtained shows that Ebedi Microfinance bank can plan effective marketing of their products and services by obtaining a guiding report on the status of their customers which will go a long way in assisting management in saving significant amount of money that could have been spent on wasteful promotional campaigns.

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A Differentiated QoS Supporting PPS Solution Based on CICQ

A Differentiated QoS Supporting PPS Solution Based on CICQ

Li Xiuqin, Yang Xiliang, Lan Julong

Статья научная

Based on the study of the existing PPS scheduling mechanism, we propose a novel PPS scheme for Differentiated QoS based on CICQ. The scheduling mechanism adopt in order queuing way to solve sequence preserving problem and set a small amount of buffer in the multiplexer to achieve differentiated QoS guarantee for different traffics which Ensure switch can provide effective support for different traffics in high-level. The simulation result indicates that the throughput of the mechanism can reach up to 99.97% at full load, and can according to the reservation bandwidth to allocate the bandwidth of output links, and ensure packets have an upper delay bound, and can balance the load to the exchange planes. Compared to the current mainstream PPS design, the mechanism is simple and easily implemented in hardware.

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A Distributed Fault Tolerance Global Coordinator Election Algorithm in Unreliable High Traffic Distributed Systems

A Distributed Fault Tolerance Global Coordinator Election Algorithm in Unreliable High Traffic Distributed Systems

Danial Rahdari, Amir Masoud Rahmani, Niusha Aboutaleby, Ali Sheidaei Karambasti

Статья научная

Distributed systems consist of several management sites which have different resource sharing levels. Resources can be shared among inner site and outer site processes at first and second level respectively. Global coordinator should exist in order to coordinate access to multi site’s shared resources. Moreover; some other coordinators should manage access to inner site’s shared resources so that exerting appropriate coordinator election algorithms in each level is crucial to achieve most efficient system. In this paper a hierarchical distributed election algorithm is proposed which eliminates single point of failure of election launcher. Meanwhile traffic is applied to network at different times and the number of election messages is extremely decreased as well which applies more efficiency especially in high traffic networks. A standby system between coordinators and their first alternative is considered to induct less wait time to processes which want to communicate with coordinator.

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A Dynamic Reputation-Based Approach for Web Services Discovery

A Dynamic Reputation-Based Approach for Web Services Discovery

Emad Elabd

Статья научная

Web services discovery is a crucial process in the service-oriented architecture (SOA). This process depends on the functional and non-functional (Quality of services (QoS)) properties of the published services. Functional properties present the objectives of the service and the quality of the service indicates the performance of the service. Reputation of the services is one of the important QoS properties. Assigning robust and precise reputation values for the service affects positively in the output of the web services discovery process by returning the most relevant services for the consumer. In this paper, we propose an approach for updating reputation of the Web services based on the trust factors of the consumers and two pre-defined thresholds, reputation threshold, and agreement threshold. The proposed approach is implemented and tested on a set of services. The results show that the proposed reputation updating approach is powerful and gives robust and precise results in a dynamic way. As a consequence, the web service discovery process which is based on the proposed approach gives a robust and precise results in a dynamic way.

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A Face Recognition Approach Based on Entropy Estimate of the Nonlinear DCT Features in the Logarithm Domain Together with Kernel Entropy Component Analysis

A Face Recognition Approach Based on Entropy Estimate of the Nonlinear DCT Features in the Logarithm Domain Together with Kernel Entropy Component Analysis

Arindam Kar,Debotosh Bhattacharjee, Dipak Kumar Basu, Mita Nasipuri, Mahantapas Kundu

Статья научная

This paper exploits the feature extraction capabilities of the discrete cosine transform (DCT) together with an illumination normalization approach in the logarithm domain that increase its robustness to variations in facial geometry and illumination. Secondly in the same domain the entropy measures are applied on the DCT coefficients so that maximum entropy preserving pixels can be extracted as the feature vector. Thus the informative features of a face can be extracted in a low dimensional space. Finally, the kernel entropy component analysis (KECA) with an extension of arc cosine kernels is applied on the extracted DCT coefficients that contribute most to the entropy estimate to obtain only those real kernel ECA eigenvectors that are associated with eigenvalues having high positive entropy contribution. The resulting system was successfully tested on real image sequences and is robust to significant partial occlusion and illumination changes, validated with the experiments on the FERET, AR, FRAV2D and ORL face databases. Experimental comparison is demonstrated to prove the superiority of the proposed approach in respect to recognition accuracy. Using specificity and sensitivity we find that the best is achieved when Renyi entropy is applied on the DCT coefficients. Extensive experimental comparison is demonstrated to prove the superiority of the proposed approach in respect to recognition accuracy. Moreover, the proposed approach is very simple, computationally fast and can be implemented in any real-time face recognition system.

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A Formal Description of Problem Frames

A Formal Description of Problem Frames

Souleymane KOUSSOUBE, Roger NOUSSI, Balira O. KONFE

Статья научная

Michael Jackson defines a Problem Frame as a mean to describe and classify software development problems. The initial description of problem Frames is essentially graphical. A weakness of this proposal is the lack of formal specification allowing efficient reasoning tools. This paper deals with Problem Frames’ formal specification with Description Logics. We first propose a formal terminology of Problem Frames leading to the specification of a Problem Frames’ TBOX and a specific problem’s ABOX. The Description Logics inference tools can then be used to decompose multi frame problems or to fix a particular problem into a Problem Frame.

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A Framework for Assessing the Software Reusability using Fuzzy Logic Approach for Aspect Oriented Software

A Framework for Assessing the Software Reusability using Fuzzy Logic Approach for Aspect Oriented Software

Pradeep Kumar Singh, Om Prakash Sangwan, Amar Pal Singh, Amrendra Pratap

Статья научная

Software reusability is very important and crucial attribute to evaluate the system software. Due to incremental growth of software development, the software reusability comes under attention of many researcher and practitioner. It is pretty easier to reuse the software than developing the new software. Software reusability reduces the development time, cost and effort of software product. Software reusability define the depth to which a module can be reused again with very little or no modification. However the prediction of this quality attribute is cumbersome process. Aspect oriented software development is new approach that introduce the concerns to overcome the issues with modular programming and object oriented programming. However many researcher worked on accessing the software reusability on object oriented system but the software reusability of aspect oriented system is not completely explored. This paper explores the various metric that affects the reusability of aspect oriented software and estimate it using fuzzy logic approach.

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A Framework for Effective Object-Oriented Software Change Impact Analysis

A Framework for Effective Object-Oriented Software Change Impact Analysis

Bassey Isong, Obeten Ekabua

Статья научная

Object-oriented (OO) software have complex dependencies and different change types which frequently affect their maintenance in terms of ripple-effects identification or may likely introduce some faults which are hard to detect. As change is both important and risky, change impact analysis (CIA) is a technique used to preserve the quality of the software system. Several CIA techniques exist but they provide little or no clear information on OO software system representation for effective change impact prediction. Additionally, OO classes are not faults or failures-free and their fault-proneness is not considered during CIA. There is no known CIA approach that incorporates both change impact and fault prediction. Consequently, making changes to software components while neglecting their dependencies and fault-proneness may have some unexpected effects on their quality or may increase their failure risks. Therefore, this paper proposes a novel framework for OO software CIA that allows for impact and fault predictions. Moreover, an intermediate OO program representation that explicitly represents the software and allows its structural complexity to be quantified using complex networks is proposed. The objective is to enhance static CIA and facilitate program comprehension. To assess its effectiveness, a controlled experiment was conducted using students’ project with respect to maintenance duration and correctness. The results obtained were promising, indicating its importance for impact analysis.

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A Framework for Multi-Tenant Database Adoption based on the Influencing Factors

A Framework for Multi-Tenant Database Adoption based on the Influencing Factors

Olumuyiwa Matthew, Kevan Buckley, Mary Garvey

Статья научная

Multi-tenant databases (MTD) are aspect of computing that has become one of the revolutionary technologies of recent years. This technology has helped to discard the large-scale investments in hardware and software resources, in upgrading them regularly and also in expensive licences of application software used on in-house hosted database systems. A MTD is a way of deploying a Database as a Service (DaaS) for the convenience and benefits of tenants. This concept is good for higher scalability and flexibility but it involves a lot of technicalities. The adoption of a MTD is based on some salient factors which can be grouped into four categories for easy understanding. A survey is presented in this research that involves a focus group of thirty respondents. The result shows the degree of impact each factor has on the decision to adopt a MTD. This paper also considers these factors and develops a framework that will help prospective tenants to take an informed decision about the adoption of the concept.

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