Статьи журнала - International Journal of Information Technology and Computer Science
Все статьи: 1165
A Novel Image Encryption Scheme Based on Reversible Cellular Automata and Chaos
Статья научная
In this paper, a new scheme for image encryption is presented. The scheme is based on a chaotic map and cellular automata (CA). CA is a collection of cells arranged in a grid, such that each cell changes state as a function of time according to a defined set of rules that includes the states of neighboring cells. The major disadvantages of cellular automata in cryptography include limited number of reversal rules and inability to produce long sequences of states by these rules. In this paper, reversible cellular automaton is presented and used to solve this problem. The presented scheme is applied in three individual steps. Firstly, the image is blocked and the pixels are substituted by a reversible cellular automaton. Then, image pixels are scrambled by a chaos map that is produced by an elementary cellular automata and finally the blocks are attached and pixels are substituted by an individual reversible cellular automaton. Due to reversibility of used cellular automata, decryption scheme can reversely be applied. The experimental results show that encrypted image is suitable visually and this scheme has satisfied quantitative performance.
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A Novel Method for Grayscale Image Segmentation by Using GIT-PCANN
Статья научная
PCNN has been widely used in image segmentation. However, satisfactory results are usually obtained at the expense of time-consuming selection of PCNN parameters and the number of iteration. A novel method, called grayscale iteration threshold pulse coupled neural network (GIT-PCNN) was proposed for image segmentation, which integrates grayscale iteration threshold with PCNN. In this method, traditional PCNN is simplified so that there is only one parameter to be determined. Furthermore, the PCNN threshold is determined iteratively by the grayscale of the original image so that the image is segmented through one time of firing process and no iteration or specific rule is needed as the iteration stop condition. The method demonstrates better performance and faster compared to those PCNN based segmentation algorithms which require the number of iterations and image entropy as iteration stop condition. Experimental results show the effectiveness of the proposed method on segmentation results and speed performance.
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A Novel Quantum Inspired Cuckoo Search Algorithm for Bin Packing Problem
Статья научная
The Bin Packing Problem (BPP) is one of the most known combinatorial optimization problems. This problem consists to pack a set of items into a minimum number of bins. There are several variants of this problem; the most basic problem is the one-dimensional bin packing problem (1-BPP). In this paper, we present a new approach based on the quantum inspired cuckoo search algorithm to deal with the 1-BPP problem. The contribution consists in defining an appropriate quantum representation based on qubit representation to represent bin packing solutions. The second contribution is proposition of a new hybrid quantum measure operation which uses first fit heuristic to pack no filled objects by the standard measure operation. The obtained results are very encouraging and show the feasibility and effectiveness of the proposed approach.
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A Novel Software Tool to Generate Customer Needs for Effective Design of Online Shopping Websites
Статья научная
Effective design of online shopping websites is the need of the hour as design plays a crucial role in the success of online shopping businesses. Recently, the use of Quality Function Deployment (QFD) has been reported for the design of online shopping websites. QFD is a customer driven process that encompasses voluminous data gathered from customers through several techniques like personal interview, focus groups, surveys etc. This massive, unsorted and unstructured data is required to be transformed into a limited number of structured information to represent the actual Customer Needs (CNs) which are then utilized in subsequent stages of QFD process. This can be achieved through brainstorming using techniques like Affinity Process. However, integrating the Affinity Process within QFD is tedious and time consuming and cannot be dealt with manually. This generates a pressing need for a software tool to serve the purpose. Moreover, the researches carried out so far have focused on QFD application, post the generation of CNs. Also, the available QFD softwares lack the option to generate CNs from collected data. Thus, the paper aims to develop a novel software tool that integrates Affinity Process with QFD to generate customers' needs for effective design of online shopping websites. The software system is developed using Visual Basic Dot Net (VB.Net) that integrates a MS-Access database.
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A Novel and Efficient Method for Protecting Internet Usage from Unauthorized Access Using Map Reduce
Статья научная
The massive increases in data have paved a path for distributed computing, which in turn can reduce the data processing time. Though there are various approaches in distributed computing, Hadoop is one of the most efficient among the existing ones. Hadoop consists of different elements out of which Map Reduce is a scalable tool that enables to process a huge data in parallel. We proposed a Novel and Efficient User Profile Characterization under distributed environment. In this frame work the network anomalies are detected by using Hadoop Map Reduce technique. The experimental results clearly show that the proposed technique shows better performance.
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A Parallel Ring Method for Solving a Large-scale Traveling Salesman Problem
Статья научная
A parallel approach for solving a large-scale Traveling Salesman Problem (TSP) is presented. The problem is solved in four stages by using the following sequence of procedures: decomposing the input set of points into two or more clusters, solving the TSP for each of these clusters to generate partial solutions, merging the partial solutions to create a complete initial solution M0, and finally optimizing this solution. Lin-Kernighan-Helsgaun (LKH) algorithm is used to generate the partial solutions. The main goal of this research is to achieve speedup and good quality solutions by using parallel calculations. A clustering algorithm produces a set of small TSP problems that can be executed in parallel to generate partial solutions. Such solutions are merged to form a solution, M0, by applying the "Ring" method. A few optimization algorithms were proposed to improve the quality of M0 to generate a final solution Mf. The loss of quality of the solution by using the developed approach is negligible when compared to the existing best-known solutions but there is a significant improvement in the runtime with the developed approach. The minimum number of processors that are required to achieve the maximum speedup is equal to the number of clusters that are created.
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A Partial Ordered Number System for Information Flow Control
Статья научная
Information flow control models can be applied widely. This paper discusses only the models preventing information leakage during program execution. In the prevention, an information flow control model dynamically monitors statements that will cause information flows and ban statements that may cause leakage. We involved in the research of information flow control for years and identified that sensitive information may be leaked only when it is output. However, most existing models ignore information flows induced by output statements. We thus designed a new model XIFC (X information flow control) that especially emphasizes the monitoring of output statements. We also designed XIFC as a precise and low runtime overhead model. To achieve this purpose, we took a different viewpoint to re-examine the features offered by existing models and extracted a necessary feature set for the design. Our experiments show that XIFC bans every non-secure information flow and substantially reduces runtime overhead when comparing with our previous work.
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A Pragmatic Approach for E-governance Evaluation Built over Two Streams (of Literature)
Статья научная
The paper presents a pragmatic approach for e-governance evaluation by constructing a methodology built over two streams of literature i.e. e-governance and evaluation. In the available literature, e-governance evaluation approaches are mostly discussed from only e-governance perspective. The paper will investigate the use of exploiting both streams of literature in designing the e-governance evaluation. The fundamentals concepts from both streams of literature mutually contribute to build an e-governance evaluation framework e.g. e-government development models, e-governance dimensions, delivery models and e-governance evaluation modes are extracted from e-governance streams while evaluation processes and evaluation methods and techniques are adopted from the evaluation stream. The paper presents an e-governance evaluation process spanning five phases (pre-evaluation development, manipulation, action, and outcome utilization).The use of the evaluation literature in e-governance evaluation framework enable the approach result-oriented and pragmatic i.e. outcome utilization phase that is added in the e-governance evaluation process ensures that the evaluation outcomes trigger learning process in the government body and are not dispensed for merely benchmarking.
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A Proposal of Case Based Reasoning System for the Appropriate Selection of Components Using CBD
Статья научная
Software engineering starts to be less linked to the development, but at the same time it tends to rely on using the component-based software. The community interested in software engineering has proposed what is called software reuse and offered some ways for component-based software development. The basic difficulty encountered when designing component-based systems is the process of searching for and selecting the appropriate set of the current software components. Selecting a component is considered a hard task in the Component Based Software Engineering (referred to as CBSE), particularly with the augmentation of the number of the component development. Hence, it is hard to select component for CBSE. Different ways and approaches were suggested to solve the problem related to software component selection. Validation of the proposed solution in this paper through collecting a sample of people who answer an electronic survey that composed of 15 questions. An electronic survey target distributed to specialists in software engineering through social sites such as twitter and Facebook also by email them. The result of the validation of the proposed solution proved using a new improvement CBR system to do select the suitable component.
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A Proposed Model for Datacenter in -Depth Defense to Enhance Continual Security
Статья научная
Defense in Depth is practical strategy for achieving Information Assurance in today’s highly datacenter environments. It is a “best practices” strategy in that it relies on the intelligent application of techniques and technologies that exist today. The strategy recommends a balance between the protection capability and cost, performance, and operational considerations. This paper provides an overview of the major elements of the strategy and provides links to resources that provide additional insight. Companies need to address the security challenges of datacenter using a comprehensive defense-in-depth strategy. No single security solution will keep a determined thief from the goal of compromising the hardware or software given enough time and resources. Applying multiple layers of system security will slow the progress made by a thief, and hopefully, force the thief to abandon the pursuit, at the least, resale of the stolen property, and at worst, of confidential corporate data. The Defense in depth is the concept of protecting a Datacenter with a series of defensive mechanisms such that if one mechanism fails, another will already be in place to thwart an attack. In this paper, the main focus is given to highlight the security aspects of data center from perspectives of threats and attacks from one side and approaches for solutions from the other side. The paper also proposes an effective and flexible distributed scheme with two salient features. Our scheme achieves the integration of continual security improvement and Security Risk localization. This paper deals with the implementation of defense in depth at a strategic, principle-based level and provides additional guidance on specific sets of controls that may be applicable to support an organization’s defense in depth initiatives. The paper will present in Section (1) the Defense in depth concept, Section (2) Threats, Adversaries, Motivations, Classes of Attack and Vulnerability Analysis, Section (3) Information Security Assurance, Defense in Multiple Places, Layered Defenses, Security Robustness, Section (4) Design Goals and finally proposed solution and provide The IT Security Role & Functional Matrix.
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A Proposed Model for Web Proxy Caching Techniques to Improve Computer Networks Performance
Статья научная
One of the most important techniques for improving the performance of web based applications is web proxy caching Technique. It is used for several purposes such as reduce network traffic, server load, and user perceived retrieval delays by replicating popular content on proxy caches that are strategically placed within the network. The use of web proxy caching is important and useful in the government organizations that provides services to citizens and has many branches all over the country where it is beneficial to improve the efficiency of the computer networks performance, especially remote areas which suffer from the problem of poor network communication. Using of proxy caches provides all users in the government computer networks by reducing the amount of redundant traffic that circulates through the network. It also provides them by getting quicker access to documents that are cached. In addition, there are a lot of benefits we can obtain from the using of proxy caches but we will address them later. In this research, we will use web proxy caching to provide all of the above benefits that we are mentioned above and to overcome on the problem of poor network communication in ENR (Egyptian National Railways). We are going to use a scheme to achieve the integration of forward web proxy caching and reverse proxy caching.
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A Proposed Process Model for Requirements Engineering using Delphi Techniques for Prioritisation
Статья научная
Requirements engineering (RE) addresses the first software development step and lays the foundation for a successful system. Consequently, ability to identify problems and suggestions for improvements in the RE process opens up significant potential for increasing the success of software projects. Since RE process is naturally collaborative in nature, the intensiveness from both knowledge and human perspectives opens up the problem of decision making on requirements that can be facilitated by requirements prioritisation. In this regard, the paper opined the need for requirements prioritization techniques that will help the developers to obtain consensus among stakeholders using a suitable technique. In particular, the paper proposed a RE process model using Delphi technique. The Delphi technique was suggested in this paper to facilitate and enhance the process of requirements prioritisation in a multilevel prioritisation dimension. Therefore, the proposed model on implementation will contribute to the formulation of an interactive framework for requirements prioritisation to produce a requirement ordering which complies with the existing priorities.
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A Proposed Virtualization Technique to Enhance IT Services
Статья научная
System virtualization is an antique art that will continue as long as applications need isolation and performance independence. Virtualization provides many benefits and greater efficiency in CPU utilization, greener IT with less power consumption, better management through central environmental control, more availability, reduced project timelines by eliminating hardware procurement, improved disaster recovery capability, more central control of the desktop, and improved outsourcing services. In this paper we will deliver new and enhanced IT services in less time and with greater agility. The goal of providing rapid near real-time response to customer requirements is in part being achieved by taking advantage of virtualization. Virtualization provides many benefits, including improved physical resource utilization, improved hardware efficiency, and reduced power and cooling expenses. However, it introduces another set of systems (virtual machines) that have to be controlled, provisioned, managed, updated, patched, and retired. This paper is organized into the following areas- An introduction to virtualization and its benefits, the Challenges of Virtualization techniques, an overview of the hardware virtualization technique, an overview of the software virtualization technique. The paper also proposes an effective and flexible distributed scheme with three phases, opposing to its predecessors. Our scheme achieves reducing the workload of a data center and continual service improvement.
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A Proxy based Framework for Efficient Range Query Processing in a Cellular Network
Статья научная
Within the last decade, the continuous development of mobile technology has motivated an intense research in mobile data services. Among these services, location-based services and location-dependant queries have attracted a lot of attention from the software industry as well as from researchers. Although a number of locations based service methods have been proposed, the performance is not satisfactory in the case of dynamic data management problems that introduce high overhead in update and query operations. In this paper, we introduce a proxy based distributed dynamic data management architecture for location based services that reduces network cost with required quality of service (QoS). The system proposes a distributed hierarchical database structure with collocated proxy for efficient service delivery to location-dependant queries especially Range Queries (RQ). The system that we propose have the following advantages. i) It performs efficient processing of location dependant queries, especially Range Queries spanning over multiple network cells ii) It reduces wireless communication between mobile devices and servers. iii) The system is scalable where location data is distributed and arranged hierarchically. We use proxy objects to carry out processing task for each mobile user. Thus proxies play an important role and in charge of routing the queries to different (distributed) databases and present the results to queries efficiently. Simulation study shows the effectiveness of our proposed architecture.
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A Quality Assessment of Watermarked Color Image Based on Vision Masking
Статья научная
The quality assessment of the watermarked color image is one of the most important aspects that evaluate the performance of watermarking system. PSNR is the common quality assessment of the watermarked image. But the results measured by PSNR usually do not match to human vision well and result in misleading. The discrete cosine transform was used as the image analysis tools. The psychophysical research -- the luminance, texture, frequency and color masking on human vision were analyzed and used in masking strength calculation. Then a vision masking calculation method of image DCT coefficients was given in this paper. Based on the masking strength calculation, a new quality assessment of watermarked color image was proposed. Experimental results showed that the new quality assessment outperforms PSNR. The distorted image quality values calculated using the new quality assessment are consistent with the perception of human vision and have high correlation and consistency with subjective values.
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A Real-Time 6DOF Computational Model to Simulate Ram-Air Parachute Dynamics
Статья научная
Computer simulations are used in many disciplines as a methodology of mimicking behaviors of a physical system or a process. In our study we have developed a real-time six degree- of-freedom (6DOF), computational model that can replicate the dynamics of a ram-air parachute system which is the design of parachute that is widely used by the militaries worldwide for parachute jumps. The proposed model is expected to be adapted in to a real-time visual simulator which would be used to train parachute jumpers. A statistical evaluation of the proposed model is done using a dataset taken from NASA ram-air parachute wind tunnel test.
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A Remote Access Security Model based on Vulnerability Management
Статья научная
Information security threats exploit vulnerabilities in communication networks. Remote access vulnerabilities are evident from the point of communication initialization following the communication channel to data or resources being accessed. These threats differ depending on the type of device used to procure remote access. One kind of these remote access devices can be considered as safe as the organization probably issues it to provide for remote access. The other type is risky and unsafe, as they are beyond the organization’s control and monitoring. The myriad of devices is, however, a necessary evil, be it employees on public networks like cyber cafes, wireless networks, vendors support, or telecommuting. Virtual Private Network (VPN) securely connects a remote user or device to an internal or private network using the internet and other public networks. However, this conventional remote access security approach has several vulnerabilities, which can take advantage of encryption. The significant threats are malware, botnets, and Distributed Denial of Service (DDoS). Because of the nature of a VPN, encryption will prevent traditional security devices such as a firewall, Intrusion Detection System (IDS), and antivirus software from detecting compromised traffic. These vulnerabilities have been exploited over time by attackers using evasive techniques to avoid detection leading to costly security breaches and compromises. We highlight numerous shortcomings for several conventional approaches to remote access security. We then adopt network tiers to facilitate vulnerability management (VM) in remote access domains. We perform regular traffic simulation using Network Security Simulator (NeSSi2) to set bandwidth baseline and use this as a benchmark to investigate malware spreading capabilities and DDoS attacks by continuous flooding in remote access. Finally, we propose a novel approach to remote access security by passive learning of packet capture file features using machine learning and classification using a classifier model.
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A Review of Coupling Simulator for Vehicular Ad-hoc Networks
Статья научная
In recent years, continuous progress in wireless communication has opened a new research field in computer networks. Now a day's wireless ad-hoc networking is an emerging research technology that needs attention of the industry people and the academicians. A vehicular ad-hoc network uses vehicles as mobile nodes to create mobility in a network. Simulation is the reproduction of the method of real-world practices. The computer simulation runs on a single or a network of computers to model and reproduce the behaviour of a system. This is based upon the conceptual model to simulate the system. In this research paper, we will discuss the coupling simulator VanetMobiSim and NS2 for vehicular ad-hoc networks. This output will be useful in implementing efficient tools on the realistic highway scenario, especially for four-wheeler traffic types in VANETs.
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A Review of Various Transform Domain Digital Image Fusion for Multifocus Colored Images
Статья научная
Image fusion is the idea to enhance the image content by fusing two or more images obtained from visual sensor network. The main goal of image fusion is to eliminate redundant information and merging more useful information from source images. Various transform domain image fusion methods like DWT, SIDWT and DCT, ACMax DCT etc. are developed in recent years. Every method has its own advantages and disadvantages. ACMax Discrete cosine transform (DCT) is very efficient approach for image fusion because of its energy compaction property as well as improve quality of image. Furthermore, this technique has also some disadvantages like color artifacts, noise and degrade the sharpness of edges. In this paper ACMax DCT method is integrated with saturation weighting and Joint Trilateral filter to get the high quality image and compare with traditional methods. The results have shown that ACMax DCT with Saturation weighting and Joint Trilateral filter method has outperformed the state of art techniques.
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A Review on the Knowledge Representation Models and its Implications
Статья научная
Data and Information has seen exponential growth in the past few years which has led to its importance in processing it in the creation of knowledge. Representing knowledge in a required format is the need for the building a knowledgebase (KB) for Expert Systems. In this paper we carried a survey on the knowledge representation models that will help us choose a suitable model for designing and developing a KB. A detailed study is conducted on six models and comparison of the models on some non-functional attributes are carried out to enable knowledge workers to decide on the model selection.
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