Статьи журнала - International Journal of Information Technology and Computer Science
Все статьи: 1195
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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Статья научная
The rise of popularity of Digital video in the past decade has been tremendous thereby leading to malicious copying and distribution. So the need for preservation of ownership and in tackling copyright issues has become an imminent issue. Digital Video Watermarking has been in existence as a solution for this. The paper proposes a non-blind watermarking technique based on combined DWT-DFT transforms using singular values of SVD matrix in YCbCr color space. The technique uses Fibonacci series for selection of frames to enhance security and thereby maintaining quality of original video. Watermark encryption is done by scrambling the watermark using Arnold transform. Geometric and non-geometric attacks on watermarked video have been performed to test the robustness of the proposed technique. Quality of watermarked video is measured using PSNR and NC gives the similarity between extracted and the original watermark.
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A SCPS-NP Routing Algorithm Based on Mobile IP Routing
Статья научная
Space communication protocol is a challenging problem in the future of space network. Now Mobile IP routing is very popular in the wireless communication network. The research shows the Mobile IP network has the much similar features to the space network. A Space Communications Protocol Specification Network Protocol (SCPS-NP) routing algorithm based on Mobile IP routing is proposed in the paper. Firstly, some basic knowledge about SCPS is introduced. The flooding routing algorithm in SCPS-NP protocol is studied. A new routing algorithmoptimized Mobile IP routing algorithm based on QoS is proposed. In order to verify the effects of the algorithm, A simulation model using NS2 network simulation tools is built and the comparisons between traditional Mobile IP routing and improved SCPS-NP routing are provided. The results show that optimized routing algorithm based on QoS could achieve better performance than traditional Mobile IP. Further, a working prototype based on SCPS-NP Gateway is implemented to test the algorithm’s application. It shows that algorithm based on Mobile IP routing can be used in the future space network.
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A Secure and Semi-Blind Technique of Embedding Color Watermark in RGB Image Using Curvelet Domain
Статья научная
A semi-blind and secure watermarking technique for the color image using curvelet domain has been proposed. To make the algorithm secure a Bijection mapping function has been used. The watermark also separated into color planes and each color plane into a bit planes. The most significant bit (MSB) planes of each color used as the embedding information and remaining bit planes are used as a key at the time of extraction. The MSB planes of each color of watermark image embedded into the curvelet coefficients of the blue color plane of the processed cover image. For embedding the MSB bit planes of watermark image in the cover image each curvelet coefficient of blue planes of the processed cover image has been compared with the value of its 8 connected coefficients (neighbors). The results of the watermarking scheme have been analyzed by different quality assessment metric such as PSNR, Correlation Coefficient (CC) and Mean Structure Similarity Index Measure (MSSIM). The experimental results show that the proposed technique gives the good invisibility of watermark, the quality of extracting watermark and robustness against different attacks.
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A Security Scheme against Wormhole Attack in MAC Layer for Delay Sensitive Wireless Sensor Networks
Статья научная
The main objective of this paper is to secure a cross-layer, energy efficient MAC protocol (CL-MAC) dedicated to delay sensitive wireless sensor networks (WSN) for detecting and avoiding wormhole attack. CL-MAC protocol is the result of our previous research works for which the security aspects have not been taken into consideration during its design stage. To formally prove the importance of the proposed scheme, we provide a theoretical study based on Time Petri Net to analyse some important properties related to the devastating effect of the wormhole attack and its countermeasure on the CL-MAC operations. Also, we perform an experimental evaluation through the simulation using realistic scenarios in order to show the performance of the proposal in terms of energy saving, packets loss ratio and latency. The obtained results indicate the usefulness of the formal study provided in this work when applied in security context and confirm clearly a good performance of the proposed scheme against wormhole attack.
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A Semantic Approach to the Notion of Representation and Its Application to Information Systems
Статья научная
Representation is a key concept for information systems (IS). IS is designated to provide information. However, the most available information systems such as databases using a computer are actually data storage and management systems because all they handle are data, which may be used to represent information. Therefore, a good understanding on the relationships between data, information and representation is vital for our study of information systems. And yet, it would seem that in the literature of information systems, the notion of representation has not been well studied, and in particular, how a possible representational relationship between two sets of data constructs may be systematically identified and how this representational relation may be explored for bearing on IS problems would seem worth looking at. The results of our investigation show that representation is a special type of signs created or being used by human agents to carry information about other states of affairs. Any representational relationship is realized and underpinned by information flow between components within an information channel. Moreover, representation can be quantitatively measured as long as certain conditions are met. The information content of representation reveals what you could possibly learn from it and the semantic content of representation is the proposition that a human originator intended to convey by using the representation. In addition, schema connections (i.e., connections between elements within a data schema) can be identified by examining the representational relationship between data entities.
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A Semantic Metadata Enrichment Software Ecosystem based on Metadata and Affinity Models
Статья научная
Information systems need to be more flexible and to allow users to find content related to their context and interests. Metadata harvesting and metadata enrichments could represent a way to help users to find content and events according to their interests. However, metadata are underused and represents an interoperability challenge. This paper presents a new framework, called SMESE, and the implementation of its prototypes that consists of its semantic metadata model, a mapping ontology model and a user interest affinity model. This proposed framework makes these models interoperable with existing metadata models. SMESE also proposes a decision support process supporting the activation and deactivation of software features related to metadata. To consider context variability into account in modeling context-aware properties, SMESE makes use of an autonomous process that exploits context information to adapt software behavior using an enhanced metadata framework. When the user chooses preferences in terms of system behavior, the semantic weight of each feature is computed. This weight quantifies the importance of the feature for the user according to their interests. This paper also proposed a semantic metadata analysis ecosystem to support data harvesting according to a metadata model and a mapping ontology model. Data harvesting is coupled with internal and external enrichments. The initial SMESE prototype represents more than 400 millions of relationships (triplets). To conclude, this paper also presents the design and implementation of different prototypes of SMESE applied to digital ecosystems.
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Статья научная
This work presents a method that enables Arabic NLP community to build scalable lexical resources. The proposed method is low cost and efficient in time in addition to its scalability and extendibility. The latter is reflected in the ability for the method to be incremental in both aspects, processing resources and generating lexicons. Using a corpus; firstly, tokens are drawn from the corpus and lemmatized. Secondly, finite state transducers (FSTs) are generated semi-automatically. Finally, FSTs are used to produce all possible inflected verb forms with their full morphological features. Among the algorithm's strength is its ability to generate transducers having 184 transitions, which is very cumbersome, if manually designed. The second strength is a new inflection scheme of Arabic verbs; this increases the efficiency of FST generation algorithm. The experimentation uses a representative corpus of Modern Standard Arabic. The number of semi-automatically generated transducers is 171. The resulting open lexical resources coverage is high. Our resources cover more than 70% Arabic verbs. The built resources contain 16,855 verb lemmas and 11,080,355 fully, partially and not vocalized verbal inflected forms. All these resources are being made public and currently used as an open package in the Unitex framework available under the LGPL license.
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A Simple Model of Mapping of Land Surface Temperature from Satellite Digital Images in Bangladesh
Статья научная
Land Surface Temperature is a key parameter in energy budget models, estimating soil moisture, forest detection and forecasting, monitoring the state of the crops and many other applications. In this work, a method has been developed to retrieve land surface temperature using the National Oceanic and Atmospheric Administration (NOAA) of USA, Advanced Very High Resolution Radiometer (AVHRR) satellite images. The land surface temperature has been determined taking AVHRR images from February to December in a year. Seasonal variations have also been studied. The results have been presented in the false color composition (fcc) map for each month. Studying the resulting maps it is found that there is a marked spatial and seasonal variations in the surface temperature among different regions of the country. We could not compare our result with the measured data as, till now, no measured data of surface temperature is available for our country. But it is observed that our result is well in conformity with the observed air temperature of the country. This method can thus be used for long term monitoring of surface parameters for the country. The long term study of surface temperature can be very much important for sustainable land resources development and to understand the effect of possible environmental changes.
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Статья научная
Processing of meteorological satellite image data provides a wealth of information useful in earth surface and environmental applications. Particularly, it is important for the estimation of different parameters of surface energy budget. In this work, a method has been developed to estimation of hourly incoming solar radiation on the surface of Bangladesh using NOAA-AVHRR satellite digital images. The model is based on the statistical regressions between the ground truth and satellite estimated values. Hundreds of full resolution images (1.1 km) for two months of the year have been processed using ERDAS IMAGINE software. Ground solar global irradiation for one place has been estimated for two months through this application. The efficiency of this method for calculating surface insolation has been checked by estimating the relative deviation between the estimated Irradiation and measured Irradiation. The method can be used for calculation of hourly irradiation over areas in a tropical environment.
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A Simulation Based Performance Comparison of AODV and DSDV Mobile Ad Hoc Networks
Статья научная
Mobile Ad hoc Network (MANET) is formed by a group of autonomous mobile nodes connected by wireless links, in which there is no backbone infrastructure. In this work, an attempt has been made to understand the characteristics/behavior of Ad hoc On Demand Distance Vector (AODV) and Destination Sequence Distance Vector (DSDV) routing protocols when operating in more challenging environment such as frequent change in network topology and node density. The performance differentials are analyzed using throughput, Packet Delivery Ratio and normalized routing load which shall provide an insight about the sensitivity of the protocols under consideration when exposed in more challenging environment. Simulation based analysis of the protocols have been done using NS-2.
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A Study and Critical Survey on Service Reusability Metrics
Статья научная
The software productivity and quality can be improved by the systematic reuse of software. Reuse and reusability are the two important factors in the software development. Reusability is a prime principle in service oriented architecture. For realizing the reuse of service, the adequacy of ability of service reuse should be properly quantified. The quantification of reuse needs a suite of metrics and many metrics are also available. Each research and publication focuses on different qualities of service to propose a set of metrics for service reusability. This paper studies the service reusability to understand the concept and survey the reusability metrics. The purpose of the paper is exploring the available service reusability metrics for further research.
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Статья научная
Semantic search engines(SSE) are more efficient than other web engines because in this era of busy life everyone wants an exact answer to his question which only semantic engines can provide. The immense increase in the volume of data, traditional search engines has increased the number of answers to satisfy the user. This creates the problem to search for the desired answer. To solve this problem, the trend of developing semantic search engines is increasing day by day. Semantic search engines work to extract the best answer of user queries which exactly fits with it. Traditional search engines are keyword based which means that they do not know the meaning of the words which we type in our queries. Due to this reason, the semantic search engines super pass the conventional search engines because they give us meaningful and well-defined information. In this paper, we will discuss the background of Semantic searching, about semantic search engines; the technology used for the semantic search engines and some of the existing semantic search engines on various factors are compared.
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A Survey Based Study on Fog Computing Awareness
Статья научная
In this day and age, the rise in technological advancements has the potential to improve and transform our lives every day. The rapid technology innovation can have a great impact on our business operations. Currently, Cloud computing services are popular and offer a wide range of opportunities for their customers. This paper presents a survey on a more recent computing architecture paradigm known as Fog Computing. Fog networking is a beneficial solution that offers the greater facility of data storage, enhanced computing, and networking resources. This new concept of fog complements cloud solution by facilitating its customers with better security, real-time analysis improved efficiency. To get a clear picture and understanding of how fog computing functions, we have performed an extensive literature review. We also presented a comparative study of fog computing with cloud and grid computing architectures. In this study, we have conducted a survey that led us to the conclusion that fog computing solution is still not applicable and implemented in most of the IoT industries due to the lack of awareness and the high architecture’s cost. Results of the study also indicate that optimized data storage and security are a few of the factors that can motivate organizations to implement the Fog computing architecture. Furthermore, the challenges related to fog computing solution are reviewed for progressive developments in the future.
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A Survey On Emotion Classification From Eeg Signal Using Various Techniques and Performance Analysis
Статья научная
In this paper, the human emotions are analyzed from EEG Signal (Electroencephalogram) with different kinds of situation. Emotions are very important in different activity and decision making. Various feature extraction techniques like discrete wavelet transform, Higher Order crossings, Independent component analysis is used to extract the particular features. Those features are used to classify the emotions with different groups like arousal and valence level using different classification techniques like Neural networks, Support vector machine etc.. Based on these emotion groups analyze the performance and accuracy for the classification are determined.
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A Survey of Catadioptric Omnidirectional Camera Calibration
Статья научная
For dozen years, computer vision becomes more popular, in which omnidirectional camera has a larger field of view and widely been used in many fields, such as: robot navigation, visual surveillance, virtual reality, three-dimensional reconstruction, and so on. Camera calibration is an essential step to obtain three-dimensional geometric information from a two-dimensional image. Meanwhile, the omnidirectional camera image has catadioptric distortion, which need to be corrected in many applications, thus the study of such camera calibration method has important theoretical significance and practical applications. This paper firstly introduces the research status of catadioptric omnidirectional imaging system; then the image formation process of catadioptric omnidirectional imaging system has been given; finally a simple classification of omnidirectional imaging method is given, and we discussed the advantages and disadvantages of these methods.
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A Survey of Unipath Routing Protocols for Mobile Ad Hoc Networks
Статья научная
A MANET (Mobile Ad hoc NETwork) is an interconnection of mobile devices by wireless links forming a dynamic topology without much physical network infrastructure such as routers, servers, access points/cables or centralized administration. Routing is a mechanism of exchanging data between the source node and the destination node. Several protocols are used to perform routing the information from the source node to the destination node. The main aim of this paper is to explore the working principles of each unipath routing protocol. The unipath routing protocols are divided into Table-Driven (Proactive), On-demand (Reactive), Hybrid routing protocols.
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