Scientific Research Publishing

Displaying 1-40 of 176 results

  • White Papers // Mar 2012

    Improved Radio Network Dimensioning for Real-Time Polling Service on IEEE 802.16 Wireless Networks With QoS Consideration

    Recently, applications of real-time Polling Service (rtPS) in IEEE 802.16 wireless networks have gained considerable popularity. These applications generate large amounts of real time traffic in the network and thus maintaining the Quality of Service (QoS) such as packet delay requirement in rtPS dominant networks is critical. Existing dimensioning methodology...

    Provided By Scientific Research Publishing

  • White Papers // Mar 2012

    An Integrative Comparison of Energy Efficient Routing Protocols in Wireless Sensor Network

    Many advances have been made in sensor technologies which are as varied as the applications; and many more are in progress. It has been reasonable to design and develop small size sensor nodes of low cost and low power. In this paper, the authors have explored some energy-efficient routing protocols...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    Energy Efficient Non-Cooperative Methods for Resource Allocation in Cognitive Radio Networks

    In a cognitive radio network wherein primary and secondary users coexist, an efficient power allocation method represents one of the most important key aspects. This paper provides a novel approach based on a game theory framework to solve this problem in a distributed and fair way. Formulated as an optimization...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    Utilizing Colored Pheromones and Helping Ants for Wireless Mesh Networks Routing

    Improving routing algorithm performance not only leads to appreciate the quality of data transmission, but also increases the speed of data transfer. In this paper, the authors propose a hybrid method which is a combination of traffic classification by the help of colored pheromones and helping ants method in the...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    An Improved Name Disambiguation Method Based on Atom Cluster

    An improved name disambiguation method based on atom cluster. Aiming at the method of character-related properties of similarity based on information extraction depends on the character information, a new name disambiguation method is proposed, and improved k-means algorism for name disambiguation is proposed in this paper. The cluster analysis cluster...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    NAMD Package Benchmarking on the Base of Armenian Grid Infrastructure

    The parallel scaling (parallel performance up to 48 cores) of NAMD package has been investigated by estimation of the sensitivity of interconnection on speedup and benchmark results - testing the parallel performance of Myrinet, Infini-band and Gigabit Ethernet networks. The system of ApoA1 of 92 K atoms, as well as...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    An improved Artificial Immune System based Network Intrusion Detection by Using Rough Set

    With the increasing worldwide network attacks, Intrusion Detection (ID) has become a popular research topic in last decade. Several artificial intelligence techniques such as neural networks and fuzzy logic have been applied in ID. The results are varied. The intrusion detection accuracy is the main focus for Intrusion Detection Systems...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    General Purpose Wireless Communication System Using Data Acquisition

    A sensor-enabled and RFID-integrated, Wireless Data Acquisition System (WDAS) that has similar functionality as Multiple Input Multiple Output (MIMO) systems for health-care applications has been developed, simulated and implemented. The system can accept various measurements via sensors placed on patients or elders and transmit information wirelessly to base station at...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    Training Based Channel Estimation in MIMO-OFDM Systems

    OFDM combined with the MIMO technique has become a core and attractive technology in future wireless communication systems and can be used to both improve capacity and quality of mobile wireless systems. Accurate and efficient channel estimation plays a key role in MIMO-OFDM communication systems, which is typically realized by...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    A New Energy Efficient Data Gathering Approach in Wireless Sensor Networks

    Data gathering in wireless sensor networks is one of the important operations in these networks. These operations require energy consumption. Due to the limited energy of nodes, the energy productivity should be considered as a key objective in design of sensor networks. Therefore, the clustering is a suitable method that...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    Usage of Pythagorean Triple Sequence in OSPF

    Internet Service Providers (ISPs) have an obligation to observe the conditions set in the Service Level Agreements (SLA) with their customers. One of the conditions is to ensure that ISPs minimize the duration of the loss of connectivity. Losses of connectivity are common occurrences most especially in networks with larger...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    A Simple Encryption Keys Creation Scheme in Wireless Ad Hoc Networks

    A Mobile Ad hoc NETwork (MANET) is a collection of mobile nodes that temporarily integrate with each other to form a network. Such a network does not require the existence of a typical network infrastructure. There is no central entity with the authority to administer the services and configurations of...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    Layer-Wise Topology Design for Cost Effective IP-Optical Networks

    Traffic engineering and topology design considering multilayer configuration have become more important. While multilayer design studies usually discuss the traffic engineering issue or reliability, this paper focuses on network construction cost in studying multilayer topology design. The number of ports for the IP layer and the maximum number of Wavelength...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2011

    Fast Handoff for 802.11 Wireless Network

    Whenever the mobile station moves from the range of one access point and comes to the range of another access point a handoff process is occurred. This process takes a long time when using the IEEE 802.11 standard handoff and this delay affect the real time and multimedia applications. This...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2011

    Sequential Tests for the Detection of Voice Activity and the Recognition of Cyber Exploits

    The authors consider the problem of automated Voice Activity Detection (VAD), in the presence of noise. To attain this objective, they introduce a Sequential Detection of Change Test (SDCT), designed at the independent mixture of Laplacian and Gaussian distributions. They analyze and numerically evaluate the proposed test for various noisy...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2011

    Application of Heuristic (1-Opt Local Search) and Metaheuristic (Ant Colony Optimization) Algorithms for Symbol Detection in MIMO Systems

    Heuristic and metaheuristic techniques are used for solving computationally hard optimization problems. Local search is a heuristic technique while Ant Colony Optimization (ACO), inspired by the ants' foraging behavior, is one of the most recent metaheuristic technique. These techniques are used for solving optimization problems. Multiple-Input Multiple-Output (MIMO) detection problem...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2011

    An Enhanced Secure Heuristic-Stochastic Routing Arithmetic in MPLS Network

    To improve routing security in MPLS network, base on the stochastic routing algorithm, the authors propose a proactive mechanism they call Enhanced Secure Heuristic-Stochastic Routing (ESHSR), which brings to bear Bayesian principle, explores the existence of multiple routes and forces packets to take alternate paths probabilistically. In this paper, the...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2011

    Turbo Codes A New PCCC Design

    Coding techniques have always been a major area of scientific interest. Due to this interest, many coding schemes were invented. Eventually, their implementation in various systems contributed in the evolvement of Wireless Communications. A breakthrough was definitely Turbo coding. Particularly, the concept of joining two or more convolutional encoders in...

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  • White Papers // Nov 2011

    Impact of Channel Dynamics, Combined Nonlinearities and ASE Noise on Transmission Performance of all Optical Star WDM Networks

    For all optical Wavelength Division Multiplexing (WDM) network based on G.653 fibers, the authors investigate the quality factor deterioration due to combined nonlinear effects and Amplified Spontaneous Emission (ASE) noise for system parameters based on ITU-T Recommendation G.692. The investigation: emphasizes on Stimulated Raman Scattering (SRS) and Four Wave Mixing...

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  • White Papers // Sep 2011

    Wireless Power Generation Strategy Using EAP Actuated Energy Harvester for Marine Information Acquisition

    The energy of a radio wave is reduced through the dispersion, the refraction and the absorption because the medium transferring the vibration of a radio wave is the seawater. In the end the reduced energy of a radio wave causes the reduced transmitting length for communication, the long postponed communication...

    Provided By Scientific Research Publishing

  • White Papers // Sep 2011

    An Energy-Based Stochastic Model for Wireless Sensor Networks

    The authors propose an energy-based stochastic model of Wireless Sensor Networks (WSNs) where each sensor node is randomly and alternatively in an active and a sleep mode. They first investigate the sensor model and derive the formula of the steady-state probability when there are a number of data packets in...

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  • White Papers // Sep 2011

    Wireless Sensor Network for Monitoring Maturity Stage of Fruit

    In this paper, the authors present a wireless sensor network for monitoring the maturity stage of fruit. A dual-polarization coupled patch sensor, which is robust to environmental changes, was designed to operate at 2.45 GHz. It was attached to a Durian fruit for a period of days to measure the...

    Provided By Scientific Research Publishing

  • White Papers // Sep 2011

    Novel Semi-blind Channel Estimation Schemes for Rayleigh Flat Fading MIMO Channels

    In this paper, the authors propose two novel semi-blind channel estimation techniques based on QR decomposition for Rayleigh flat fading Multiple Input Multiple Output (MIMO) channel using various pilot symbols. In the first technique, the flat-fading MIMO channel matrix H can be decomposed as an upper triangular matrix R and...

    Provided By Scientific Research Publishing

  • White Papers // Sep 2011

    ANCAEE: A Novel Clustering Algorithm for Energy Efficiency in Wireless Sensor Networks

    One of the major constraints of wireless sensor networks is limited energy available to sensor nodes because of the small size of the batteries they use as source of power. Clustering is one of the routing techniques that have been using to minimize sensor nodes' energy consumption during operation. In...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    An Improved MPH-Based Delay-Constrained Steiner Tree Algorithm

    In order to optimize cost and decrease complexity with a delay upper bound, the delay-constrained Steiner tree problem is addressed. Base on the new Delay-Constrained MPH (DCMPH) algorithm and through improving on the select path, an improved MPH-based delay-constrained Steiner tree algorithm is presented in this paper. With the new...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Enterprise Service Bus: A Performance Evaluation

    The flexibility offered by an Enterprise Service Bus (ESB) in enabling various applications to exchange data makes it a very important middleware layer that is responsible for transporting data in a Service-Oriented Architecture (SOA). The popularity of the ESB has given rise to a number of Commercial Off The Shelf...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    MAC Sub-Layer Analysis With Channel Estimation in Broadband Power Line Communication

    Broadband Power Line Communication (BPLC) gained a lot of interest because of low cost and high performance communication network in access area. In this paper PHYsical (PHY) layer and Medium Access Control (MAC) sub-layer of BPLC are considered. Furthermore, effects of Bit Error Rate (BER) are analyzed in MAC sub-layer....

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    A Effective Method for Properties Access in MAC Layer of ZigBee

    The attribute access methods of MAC layer in wireless communication network is researched. Aiming at conquering the problem of the shared ZigBee wireless channel resulting multi-channel device conflicts when using the data channel at the same time, therefore, the protocol is improved and a method used to access the properties...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Survey on Spam Filtering Techniques

    In the recent years spam became as a big problem of Internet and electronic communication. There developed a lot of techniques to fight them. In this paper the overview of existing e-mail spam filtering methods is given. The classification, evaluation, and comparison of traditional and learning-based methods are provided. Some...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Usage of Erlang Formula in IP Networks

    This paper is concerning of Erlang formulas practical approval and their usage with video flow transfer in IP networks. Erlang formulas were simulated in MATLAB program. Practical verification was realized in defined environment by using of designed video source. The result is comparison of loss calculated by MAT-LAB and loss...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Maximizing Resilient Throughput in Peer-To-Peer Network

    A unique challenge in P2P network is that the peer dynamics (departure or failure) cause unavoidable disruption to the downstream peers. While many works have been dedicated to consider fault resilience in peer selection, little understanding is achieved regarding the solvability and solution complexity of this problem from the optimization...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Multiple Targets Tracking Using Kinematics in Wireless Sensor Networks

    Target tracking is considered as one of the cardinal applications of a wireless sensor network. Tracking multiple targets is more challenging than tracking a single target in a wireless sensor network due to targets' movement in different directions, targets' speed variations and frequent connectivity failures of low powered sensor nodes....

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  • White Papers // Aug 2011

    Performance Analysis of an Enhanced Load Balancing Scheme for Wireless Sensor Networks

    Research interest in sensor networks routing largely considers minimization of energy consumption as a major performance criterion to provide maximum sensors network lifetime. When considering energy conservation, routing protocols should also be designed to achieve fault tolerance in communications. Moreover, due to dynamic topology and random deployment, incorporating reliability into...

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  • White Papers // Aug 2011

    Modeling of Data Reduction in Wireless Sensor Networks

    In this paper, the authors present a stochastic model for data in a Wireless Sensor Network (WSN) using random field theory. The model captures the space-time behavior of the underlying phenomenon being observed by the network. They present results regarding the size and spatial distribution of the regions of the...

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  • White Papers // Aug 2011

    Characterization Process of MOSFET With Virtual Instrumentation for DP4T RF Switch - A Review

    With the increasing interest in radio frequency switch by using the CMOS circuit technology for the wireless communication systems is in demand. A traditional n-MOS Single-Pole Double-Throw (SPDT) switch has good performances but only for a single operating frequency. For multiple operating frequencies, to transmitting or receiving information through the...

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  • White Papers // Jul 2011

    A High-Level Architecture for Intrusion Detection on Heterogeneous Wireless Sensor Networks: Hierarchical, Scalable and Dynamic Reconfigurable

    Networks protection against different types of attacks is one of most important posed issue into the network and information security domains. This problem on Wireless Sensor Networks (WSNs), in attention to their special properties, has more importance. Now, there are some of proposed solutions to protect Wireless Sensor Networks (WSNs)...

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  • White Papers // Jul 2011

    An Exploratory Study of Experimental Tools for Wireless Sensor Networks

    The objective of this contribution is to present expositive review content on currently available experimental tools/services/concepts used for most emerging field Wireless Sensor Network that has capability to change many of the Information Communication aspects in the upcoming era. Currently due to high cost of large number of sensor nodes...

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  • White Papers // Jun 2011

    A New Kind of Dynamic Key Protocol for Wireless Sensor Network

    For the source limitations and vulnerabilities of the sensor nodes of Wireless Sensor Networks, the authors propose the new kind of dynamic key protocol for wireless sensor network, using the unidirection of hash function and the thinking of Hill to study the dynamic key matrix. Through theoretical analysis of some...

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  • White Papers // Jun 2011

    Cross Layer Design for Cooperative Transmission in Wireless Sensor Networks

    Several protocols and schemes have been proposed to reduce energy consumption in Wireless Sensor Networks (WSNs). In this paper, the authors employ farcoopt, a cross layer design approach with the concept of cooperation among the nodes with best farthest neighbor scheme to increase the Quality of Service (QoS), reduce energy...

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  • White Papers // Jun 2011

    MDS and Trilateration Based Localization in Wireless Sensor Network

    Localization of sensor nodes is crucial in Wireless Sensor Network because of applications like surveillance, tracking, navigation etc. Various optimization techniques for localization have been proposed in literature by different researchers. In this paper, the authors propose a two phase hybrid approach for localization using Multidimensional Scaling and trilateration, namely,...

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  • White Papers // Aug 2010

    Distance Measurement Model Based on RSSI in WSN

    The relationship between RSSI (Received Signal Strength Indication) values and distance is the foundation and the key of ranging and positioning technologies in wireless sensor networks. Log-Normal Shadowing Model (LNSM), as a more general signal propagation model, can better describe the relationship between the RSSI value and distance, but the...

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  • White Papers // Aug 2010

    A Real-Time-Enabled, Blackboard-Based, Publish/Subscribe Architecture for Wireless Sensor Nodes

    Wireless sensor network nodes have only limited resources concerning memory and battery life-time. Memory can be efficiently used by sharing data, and the life-time of a battery can be extended, when the node has long power saving sleep-phases. The authors propose a publish/subscribe architecture that achieves these two aims. The...

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  • White Papers // Jul 2010

    Performance Analysis of Downlink MIMO WCDMA Systems Using Antenna Selection in Transmitter and MRC Plus LDD in Receiver Over Correlated Nakagami-Fading Channels

    In this paper Bit Error Rate (BER) performance is analyzed for Multiple Input-Multiple Output (MIMO) communications systems using antenna selection in the transmitter, Maximal Ratio Combining (MRC) and Linear De-correlating Detector (LDD) in the receiver in Wide band Code Division Multiple Access (WCDMA) downlink channels with correlated Nakagami fading. The...

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  • White Papers // Jun 2010

    Interference Management for DS-CDMA Systems Through Closed-Loop Power Control, Base Station Assignment, and Beamforming

    In this paper, the authors propose a Smart Step closed-loop Power Control (SSPC) algorithm and a Base Station Assignment method based on Minimizing the Transmitter Power (BSA-MTP) technique in a Direct Sequence-Code Division Multiple Access (DS-CDMA) receiver with frequency-selective Rayleigh fading. This receiver consists of three stages. In the first...

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  • White Papers // May 2009

    SAGE: A Strong Privacy-Preserving Scheme Against Global Eavesdropping for eHealth Systems

    The eHealth system is envisioned as a promising approach to improving health care through information technology, where security and privacy are crucial for its success and large-scale deployment. In this paper, the authors propose a strong privacy preserving Scheme Against Global Eavesdropping, named SAGE, for eHealth systems. The proposed SAGE...

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  • White Papers // Feb 2011

    A Novel Cross-Layer Scheduling Algorithm for OFDMA-Based WiMAX Networks

    IEEE 802.16e based WiMAX networks promise a desirable available quality of service for mobile users and scheduling algorithms provide the best effective use of network resources in it. In this paper, the authors propose a novel cross-layer scheduling algorithm for OFDMA-based WiMAX networks. Their scheme employs a priority function at...

    Provided By Scientific Research Publishing

  • White Papers // Sep 2011

    Novel Semi-blind Channel Estimation Schemes for Rayleigh Flat Fading MIMO Channels

    In this paper, the authors propose two novel semi-blind channel estimation techniques based on QR decomposition for Rayleigh flat fading Multiple Input Multiple Output (MIMO) channel using various pilot symbols. In the first technique, the flat-fading MIMO channel matrix H can be decomposed as an upper triangular matrix R and...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2008

    CA-AODV: Congestion Adaptive AODV Routing Protocol for Streaming Video in Mobile Ad Hoc Networks

    Whenever streaming of multimedia based data such as video, audio and text is performed traffic will be more and network becomes congested in mobile ad hoc networks. The present routing protocols are not able to cope up with this situation. It is observed that network congestion is the dominant reason...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2008

    Towards High Quality VoIP in 3G Networks an Empirical Approach

    Third Generation (3G) packet switched WCDMA networks with High-Speed Downlink Packet Access (HSDPA) are currently being deployed worldwide to provide wireless broadband connectivity. When introducing HSDPA in 3G networks the end user experience and system capacity with voice over IP applications improve considerably. When later on adding also high-speed uplink...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2008

    OCDMA/OCDMA Overloading Scheme for Cellular DS-CDMA Using Orthogonal Gold Codes and Complex Scrambling

    Overloading is a method to extend capacity limitation of multiple access techniques. The system becomes overloaded, when the number of users exceeds the signal dimensions. One of the efficient schemes to overload a CDMA system is to use two sets of Orthogonal signal waveforms (O/O). In this paper, the BER...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2008

    Distributed Relay Diversity Systems for OFDM-Based Networks

    In this paper, distributed relay diversity systems are analyzed, modeled and evaluated in an Orthogonal Frequency Division Multiplexing (OFDM) based networks. The investigated distributed relay diversity schemes extend the ideas of a single hop transmit antenna schemes such as Cyclic Delay Diversity (CDD), Space Time Transmit Diversity (STTD), transmit Coherent...

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  • White Papers // Aug 2008

    Joint Adaptive Modulation and Power Allocation in Cognitive Radio Networks

    Link adaptation is an important issue in the design of cognitive radio networks, which aims at making efficient use of system resources. In this paper, the authors propose and investigate a joint adaptive modulation and power allocation algorithm in cognitive radio networks. Specifically, the modulation scheme and transmit power are...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2008

    Cluster-Based Design for Two-Hop Cellular Networks

    Optimal resource allocation with an objective of maximizing the system capacity is an NP-hard problem in multi-hop cellular networks. Hence, different heuristic algorithms have been developed over the years that would improve the network system capacity. In this paper, a novel cluster-based architecture is proposed for a two-hop cellular network...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    Energy Efficient Non-Cooperative Methods for Resource Allocation in Cognitive Radio Networks

    In a cognitive radio network wherein primary and secondary users coexist, an efficient power allocation method represents one of the most important key aspects. This paper provides a novel approach based on a game theory framework to solve this problem in a distributed and fair way. Formulated as an optimization...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    Utilizing Colored Pheromones and Helping Ants for Wireless Mesh Networks Routing

    Improving routing algorithm performance not only leads to appreciate the quality of data transmission, but also increases the speed of data transfer. In this paper, the authors propose a hybrid method which is a combination of traffic classification by the help of colored pheromones and helping ants method in the...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    An Improved Name Disambiguation Method Based on Atom Cluster

    An improved name disambiguation method based on atom cluster. Aiming at the method of character-related properties of similarity based on information extraction depends on the character information, a new name disambiguation method is proposed, and improved k-means algorism for name disambiguation is proposed in this paper. The cluster analysis cluster...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    NAMD Package Benchmarking on the Base of Armenian Grid Infrastructure

    The parallel scaling (parallel performance up to 48 cores) of NAMD package has been investigated by estimation of the sensitivity of interconnection on speedup and benchmark results - testing the parallel performance of Myrinet, Infini-band and Gigabit Ethernet networks. The system of ApoA1 of 92 K atoms, as well as...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    An improved Artificial Immune System based Network Intrusion Detection by Using Rough Set

    With the increasing worldwide network attacks, Intrusion Detection (ID) has become a popular research topic in last decade. Several artificial intelligence techniques such as neural networks and fuzzy logic have been applied in ID. The results are varied. The intrusion detection accuracy is the main focus for Intrusion Detection Systems...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2012

    General Purpose Wireless Communication System Using Data Acquisition

    A sensor-enabled and RFID-integrated, Wireless Data Acquisition System (WDAS) that has similar functionality as Multiple Input Multiple Output (MIMO) systems for health-care applications has been developed, simulated and implemented. The system can accept various measurements via sensors placed on patients or elders and transmit information wirelessly to base station at...

    Provided By Scientific Research Publishing

  • White Papers // Nov 2011

    Fast Handoff for 802.11 Wireless Network

    Whenever the mobile station moves from the range of one access point and comes to the range of another access point a handoff process is occurred. This process takes a long time when using the IEEE 802.11 standard handoff and this delay affect the real time and multimedia applications. This...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    An Improved MPH-Based Delay-Constrained Steiner Tree Algorithm

    In order to optimize cost and decrease complexity with a delay upper bound, the delay-constrained Steiner tree problem is addressed. Base on the new Delay-Constrained MPH (DCMPH) algorithm and through improving on the select path, an improved MPH-based delay-constrained Steiner tree algorithm is presented in this paper. With the new...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Enterprise Service Bus: A Performance Evaluation

    The flexibility offered by an Enterprise Service Bus (ESB) in enabling various applications to exchange data makes it a very important middleware layer that is responsible for transporting data in a Service-Oriented Architecture (SOA). The popularity of the ESB has given rise to a number of Commercial Off The Shelf...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    MAC Sub-Layer Analysis With Channel Estimation in Broadband Power Line Communication

    Broadband Power Line Communication (BPLC) gained a lot of interest because of low cost and high performance communication network in access area. In this paper PHYsical (PHY) layer and Medium Access Control (MAC) sub-layer of BPLC are considered. Furthermore, effects of Bit Error Rate (BER) are analyzed in MAC sub-layer....

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    A Effective Method for Properties Access in MAC Layer of ZigBee

    The attribute access methods of MAC layer in wireless communication network is researched. Aiming at conquering the problem of the shared ZigBee wireless channel resulting multi-channel device conflicts when using the data channel at the same time, therefore, the protocol is improved and a method used to access the properties...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Survey on Spam Filtering Techniques

    In the recent years spam became as a big problem of Internet and electronic communication. There developed a lot of techniques to fight them. In this paper the overview of existing e-mail spam filtering methods is given. The classification, evaluation, and comparison of traditional and learning-based methods are provided. Some...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Usage of Erlang Formula in IP Networks

    This paper is concerning of Erlang formulas practical approval and their usage with video flow transfer in IP networks. Erlang formulas were simulated in MATLAB program. Practical verification was realized in defined environment by using of designed video source. The result is comparison of loss calculated by MAT-LAB and loss...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2011

    Maximizing Resilient Throughput in Peer-To-Peer Network

    A unique challenge in P2P network is that the peer dynamics (departure or failure) cause unavoidable disruption to the downstream peers. While many works have been dedicated to consider fault resilience in peer selection, little understanding is achieved regarding the solvability and solution complexity of this problem from the optimization...

    Provided By Scientific Research Publishing

  • White Papers // May 2011

    The Behaviour of Vertical Bell Laboratories Layered Space-Time Algorithm Combined With Multiuser Detection Schemes in Wireless Communication System

    This paper provides the performance analysis of multiuser Vertical Bell Laboratories LAyered Space-Time (V-BLAST) system receiver structures for Multiple-Input Multiple-Output (MIMO) channel at a base station with assumption of perfect channel estimation and perfect timing delay estimation. In MIMO channels the receivers such as decorrelator, Minimum Mean Square Error (MMSE)...

    Provided By Scientific Research Publishing

  • White Papers // May 2011

    Evaluation of a Heterogeneous Sensor Network Architecture for Highly Mobile Users

    This paper presents experimental results of a heterogeneous sensor network architecture, which is a combination of a wireless sensor network and a personal area network. The proposed architecture uses the IEEE 802.15.4 standard to transmit sensor data to a sensor node which in turn forwards the data using TCP/IP to...

    Provided By Scientific Research Publishing

  • White Papers // May 2011

    A Preamble-Based Broadcasting Technique for Wireless Ad Hoc Sensor Networks

    Broadcasting is a fundamental operation in any wireless networks, more so in wireless ad hoc sensor net-works, where each sensor node has limited transmission range and battery power. Although broad-casting in wireless ad hoc sensor networks has many advantages but it can cause serious problems like - broadcast storm, which...

    Provided By Scientific Research Publishing

  • White Papers // May 2011

    TCP Window Based Congestion Control -Slow-Start Approach

    Transmission Control Protocol (TCP) has undergone several transformations. Several proposals have been put forward to change the mechanisms of TCP congestion control to improve its performance. A line of re-search tends to reduce speed in the face of congestion thereby penalizing itself. In this group are the window based congestion...

    Provided By Scientific Research Publishing

  • White Papers // May 2011

    Design and Simulation of a Secure and Robust Underwater Acoustic Communication System in the Persian Gulf

    In recent years, UnderWater Acoustic (UWA) communications have received much attention as their applications have begun to shift from military toward commercial. Digital communications through UWA channels differ substantially from those in other media, such as radio channels, due to severe signal degradations caused by multipath propagation and high temporal...

    Provided By Scientific Research Publishing

  • White Papers // May 2011

    On Time-of-Arrival Statistic of Gaussian Channel Model

    A model of an angle-spread source, termed the "Gaussian Channel Model" is considered. The cumulative distribution function of the Time-of-Arrival of the multipath components is derived for an arbitrary angle spread. The simple approximate expressions for the Time-of-Arrival cumulative distribution function and probability density function are proposed. Numerical results obtained...

    Provided By Scientific Research Publishing

  • White Papers // May 2011

    On Synchronization of Pinning-Controlled Networks With Reducible and Asymmetric Coupling Matrix

    Complex dynamical networks are found to be common systems in the real world, such as genetic regulatory networks, biological neural networks, telephone graphs, etc. Therefore, lots of researchers from many fields of science and engineering are attracted to focus on analyzing their complex behaviors. Particularly, the synchronization of a complex...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2011

    Fast Sparse Multipath Channel Estimation with Smooth L0 Algorithm for Broadband Wireless Communication Systems

    Broadband wireless channels are often time dispersive and become strongly frequency selective in delay spread domain. Commonly, these channels are composed of a few dominant coefficients and a large part of coefficients are approximately zero or under noise floor. To exploit sparsity of Multi-Path Channels (MPCs), there are various methods...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2011

    Efficient Power Loading in MIMO-OFDM Based Cognitive Radio Networks

    Due to their spectrum shaping capability and high adaptability, the multi-carrier systems are considered as prime candidates for use in the Cognitive Radio (CR) networks. In these structures, the deactivation of the Primary Users' (PUs) bands makes the Secondary Users (SUs) use a limited number of sub-carriers, so the total...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2011

    Statistical Recognition Method of Binary BCH Code

    In this paper, a statistical recognition method of the binary BCH code is proposed. The method is applied to both primitive and non-primitive binary BCH code. The block length is first recognized based on the cyclic feature under the condition of the frame length known. And then candidate polynomials are...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2011

    Multi-Branch Fractional Multi-Bit Differential Detection of Continuous Phase Modulation With Decision Feedback

    Differential detection of continuous phase modulation suffers from significant intersymbol interference. To reduce bit error rate, Multi-branch Fractional Multi-bit Differential Detection (MFMDD) with decision feed-back is proposed. By introducing decision feedback in multi-bit differential detected signals, severe inter-symbol interference can be removed. Simulation results show that the proposed structure can...

    Provided By Scientific Research Publishing

  • White Papers // Feb 2011

    Pilot Placement for Time-Varying MIMO OFDM Channels With Virtual Subcarriers

    The rapid time-variation of a fading multipath environment can impair the performance of Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO OFDM). This paper proposes a pilot placement method for MIMO OFDM systems under time-varying channels with the guard band. The time-varying channel is described by complex exponential Basis Expansion Model...

    Provided By Scientific Research Publishing

  • White Papers // Aug 2009

    UWB-Based Localization in Wireless Sensor Networks

    Localization has many important applications in wireless sensor networks, such as object searching and tracking, remote navigation, location based routing etc. The distance measurements have been based on a variety of technologies, such as acoustic, infrared, and UWB (Ultra-Wide Band) media for localization purposes. In this paper, the authors propose...

    Provided By Scientific Research Publishing