Scientific Research

Displaying 121-160 of 609 results

  • White Papers // Nov 2013

    Development of Battery-Less Wireless Current Sensor Node Utilizing Charging Time of Capacitors with Wide Measurement Range

    The authors report a novel battery-less wireless current sensor node without an Analog to Digital Converter (ADC). If a capacitor is charged using a Current Transformer (CT) and a rectifying circuit, the charging time depends on the current flowing through a power line. In the case that the node transmits...

    Provided By Scientific Research

  • White Papers // Nov 2013

    PSO for CWSN Using Adaptive Channel Estimation

    Wireless Sensor Network (WSN) is used in various applications. A main performance factor for WSN is the battery life that depends on energy consumption on the sensor. To reduce the energy consumption, an energy efficient transmission technique is required. Cluster Wireless Sensor Network (CWSN) groups the sensors that have the...

    Provided By Scientific Research

  • White Papers // Nov 2013

    Toward a Multi-Hop, Multi-Path Fault-Tolerant and Load Balancing Hierarchical Routing Protocol for Wireless Sensor Network

    In this paper, the authors describe a novel energy-aware multi-hop cluster-based fault-tolerant load balancing hierarchical routing protocol for a self-organizing Wireless Sensor Network (WSN), which takes into account the broadcast nature of radio. The main idea is using hierarchical fuzzy soft clusters enabling non-exclusive overlapping clusters, thus allowing partial multiple...

    Provided By Scientific Research

  • White Papers // Oct 2013

    Performance Analysis of an Autoconfiguration Addressing Protocol for Ad Hoc Networks

    A Mobile Ad hoc NETwork (MANET) is a group of mobile nodes which cooperatively and spontaneously form an IP-based network with no centralized administration. Autoconfiguration protocols are important in maintaining Mobile Ad hoc NETworks (MANETs). In this paper, the authors present an auto configuration protocol called the One-Step Addressing (OSA)...

    Provided By Scientific Research

  • White Papers // Oct 2013

    Estimation of Two-Dimensional Correction Factors for Min-Sum Decoding of Regular LDPC Code

    In this paper, Two-Dimensional (2D) correction scheme is proposed to improve the performance of conventional Min-Sum (MS) decoding of regular low density parity check codes. The adopted algorithm to obtain the correction factors is simply based on estimating the Mean Square Difference (MSD) between the transmitted codeword and the posteriori...

    Provided By Scientific Research

  • White Papers // Oct 2013

    A Survey of Software Test Estimation Techniques

    Software testing has become a complex endeavor, owing to the multiple levels of testing that are required, such as component testing, integration testing, and system testing, as well as the types of testing that need to be carried out, such as functional testing, performance testing, and security testing. Software testing...

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  • White Papers // Oct 2013

    Track Paging an Optimal Method for Minimizing Paging and Signaling Cost in Mobile IP

    Mobile IP is an Internet standards protocol, which enhances the existing Internet Protocol (IP) to accommodate mobility. In mobile IP protocol, to find the exact location of mobile node for transferring incoming packets to them has a lot of signaling cost. So increasing the performance and decreasing the signaling cost...

    Provided By Scientific Research

  • White Papers // Oct 2013

    Energy Efficient Packet-Duration-Value Based MAC Protocol for Wireless Sensor Networks

    Medium Access Control (MAC) protocol consists of sets of rules that determine which node is allowed to access the transmission medium. It provides mechanism for collision avoidance such that interfering sensor nodes do not transmit at the same time. In the literature, researchers have proposed different MAC protocols with features...

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  • White Papers // Oct 2013

    Saturated Power Control Scheme for Kalman Filtering via Wireless Sensor Networks

    The authors investigate the Kalman filtering problem via wireless sensor networks over fading channels. When part or all of the observation measurements are lost in a random fashion, they obtain the conclusion that the packet dropout probabilities depend upon the time-varying channel gains and the transmission power levels used by...

    Provided By Scientific Research

  • White Papers // Oct 2013

    On Energy-Efficient Time Synchronization for Wireless Sensors Under Large-Scale and Small-Scale Fading Effects

    In this paper, the existing trade-off between time synchronization quality and energy is studied for both large-scale and small-scale fading wireless channels. The authors analyze the clock offset estimation problem using one-way, two-way and N-way message exchange mechanisms affected by Gaussian and exponentially distributed impairments. Their main contribution is a...

    Provided By Scientific Research

  • White Papers // Oct 2013

    A U-Shaped UWB Antenna with Band-Notched Performance

    As stated in Federal Communications Commission (FCC), the Ultra-WideBand (UWB) radio systems use the designated 3.1 - 10.6GHz frequency band. Due to this large frequency range, there would be interference with WLAN technologies such as IEEE 802.11 a (5.15 - 5.35GHz, 5.725 - 5.825GHz). An ultra-wideband antenna with controllable band-notched...

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  • White Papers // Oct 2013

    Tri-Band Fractal Antennas for RFID Applications

    RFID stands for Radio Frequency IDentification, a term that describes any system of identification wherein an electronic device that uses radio frequency or magnetic field variations to communicate is attached to an item. The RFID is a rapidly developing technology. It's used in many applications such as logistics, ticketing, security,...

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  • White Papers // Oct 2013

    Performance Assessment for LTE-Advanced Networks with Uniform Fractional Guard Channel Over Soft Frequency Reuse Scheme

    Dropping probability of handoff calls and blocking probability of new calls are two important Quality of Service (QoS) measures for LTE-advanced networks. Applying QoS for Cell edge users in soft frequency reuse scheme in LTE system is a challenge as they already suffer from limited resources. Assigning some resources for...

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  • White Papers // Oct 2013

    Assisted Channel Estimation with Dynamic Allocation Pilot Subcarriers for OFDM Communications

    The channel estimation is a fundamental step in a transmission system whose performances are directly related to the severity of this step in the reception process. The estimation quality is highly dependent on variations of the channel propagation. In this paper, a transmission system based on OFDM (Orthogonal Frequency Division...

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  • White Papers // Sep 2013

    New Theoretical Aspects of Software Engineering for Development Applications and E-Learning

    In this paper, the authors present new theoretical aspects of software engineering which oriented on product lines for building applied systems and software product families from readymade reusable components in conditions of program factories. These aspects are the new disciplines such as the theory of component programming; models variability and...

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  • White Papers // Sep 2013

    Measuring Qualities of XML Schema Documents

    The eXtensible Markup Language (XML) is becoming a de-facto standard for exchanging information among the web applications. Efficient implementation of web application needs to be efficient implementation of XML and XML schema document. The quality of XML document has great impact on the design quality of its schema document. Therefore,...

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  • White Papers // Sep 2013

    Towards Enhanced Program Comprehension for Service Oriented Architecture (SOA) Systems

    Service Oriented Architecture (SOA) is an emerging paradigm for orchestrating software components to build new composite applications that enable businesses, government agencies and other organizations to collaborate across institutional boundaries. SOA offers new languages and a variety of software development tools that enable software engineers to configure software as services...

    Provided By Scientific Research

  • White Papers // Sep 2013

    Improving Parallelism in Software Development Process

    Software development process basically consists of phases, planned and executed in series: feasibility study; requirements; design and implementation, prior to production and maintenance. At the end of each phase, there may be an official management decision (go/not go) depending upon cost, time or other reasons. Within each phase or across-phases,...

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  • White Papers // Sep 2013

    Robust Cubic-Based 3-D Localization for Wireless Sensor Networks

    The rapid progress of wireless communication and the availability of many small-sized, light-weighted and low-cost communication and computing devices now-a-days have greatly impacted the development of wireless sensor network. Localization using sensor network has attracted much attention for its comparable low-cost and potential use with monitoring and targeting purposes in...

    Provided By Scientific Research

  • White Papers // Sep 2013

    Adaptive Terminal-Modality-Based Joint Call Admission Control for Heterogeneous Cellular Networks

    The coexistence of different Radio Access Technologies (RATs) requires a need for Common Radio Resource Management (CRRM) to support the provision of Quality of Service (QoS) and the efficient utilization of radio resources. The provision of QoS is an important and challenging issue in the design of integrated services packet...

    Provided By Scientific Research

  • White Papers // Sep 2013

    Simplified the QoS Factor for the Ad-Hoc Network Using Fuzzy Technique

    Quality of Service (QoS) is a tool to measure the efficiency of the ad-hoc network. QoS is a complex function because it depends mainly on four factors (throughput, packet delivery ratio, end-to-end delay and jitter). These four factors are functions of internal factors and are variables with the time. In...

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  • White Papers // Aug 2013

    Three-Dimensional Simulations with Fields and Particles in Software and Inflector Designs

    As already pointed out, fields and particles are two the most important modeling paradigms in pure and applied science at all. Particles are primarily used in one of the two ways in large scientific applications. Particles and fields represent two major modeling paradigms in pure and applied science at all....

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  • White Papers // Aug 2013

    Data Timed Sending (DTS) Energy Efficient Protocol for Wireless Sensor Networks: Simulation and Testbed Verification

    The Data Timed Sending (DTS) protocol contributes to the energy savings in Wireless Sensor Networks (WSNs) and prolongs the sensor nodes' battery lifetime. DTS saves energy by transmitting short packets, without data payload, from the sensor nodes to the base station or the cluster head according to the Time Division...

    Provided By Scientific Research

  • White Papers // Aug 2013

    Design and Implementation of Remotely Controlled Vehicle Anti-Theft System Via GSM Network

    In this paper, the authors are to build a secured and reliable vehicle anti-theft system which will have the ability to access the vehicle subsystems from a remote location where there is GSM network. And also, the design method involves the interfacing of GSM/GPRS modem module with the vehicle ignition...

    Provided By Scientific Research

  • White Papers // Aug 2013

    Smart Street Lighting Control and Monitoring System for Electrical Power Saving by Using VANET

    The huge amount of electrical power of many countries is consumed in lighting the streets. However, vehicles pass with very low rate in specific periods of time and parts of the streets are not occupied by vehicles over time. In this paper, the authors propose a system that automatically switches...

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  • White Papers // Aug 2013

    Call Admission Control in HAP W-CDMA Cellular Systems

    Among various radio sources which control different dependencies/functions, in this paper, the authors will talk about the Call Admission Control (CAC), and they are supposed to confine their concentration on W-CDMA which is based on high raised platforms, since during the recent years remarkable amount of attention has been focused...

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  • White Papers // Aug 2013

    Face Recognition Using Chain Codes

    Face recognition is an active area of biometrics. This paper investigates the use of chain codes as features for recognition purpose. Firstly a segmentation method, based on skin color model was applied, followed by contour detection then the chain codes of the contours were determined. The first difference of chain...

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  • White Papers // Aug 2013

    Student Experience and Ubiquitous Learning in Higher Education: Impact of Wireless and Cloud Applications

    Mobile learning apps for Smartphone and tablet computer devices have entered Higher Education (HE) market. While universities are investing in new technologies, they also look into cost reduction strategies, including cloud computing. The authors draw upon a case study of a successful migration to mobile virtual environment and effective use...

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  • White Papers // Jul 2013

    Computational Performances of OFDM Using Different FFT Algorithms

    In this paper, an intuitive comparison of the computational performance of Orthogonal Frequency Division Multiplexing (OFDM) system has been made in terms of complex calculations required using Different Fourier Transform (DFT) techniques. The different transform techniques are introduced such as Discrete Fourier Transform (DFT) and various types of Fast Fourier...

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  • White Papers // Jul 2013

    Introducing Intelligent Agents Potential Into a Competent Integral Multi-Agent Sensor Network Simulation Architecture Design

    In this paper, the authors spot several key issues concerning WSN design process and how to introduce intelligence in the motes. Due to the nature of these networks, debugging after deployment is unrealistic, thus an efficient testing method is required. WSN simulators perform the task, but still code implementing mote...

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  • White Papers // Jul 2013

    EEICCP - Energy Efficient Protocol for Wireless Sensor Networks

    In this paper, energy efficient inter cluster coordination protocol developed for the wireless sensor networks has been proposed. By controlling the topology, longevity and the scalability of the network can be increased. Clustering sensor node is an effective topology for the energy constrained networks. So cluster based algorithm has been...

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  • White Papers // Jul 2013

    Hadoop Based Defense Solution to Handle Distributed Denial of Service (DDoS) Attacks

    Distributed Denial of Service (DDoS) attacks continues to grow as a threat to organizations worldwide. From the first known attack in 1999 to the highly publicized operation Ababil, the DDoS attacks have a history of flooding the victim network with an enormous number of packets, hence exhausting the resources and...

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  • White Papers // Jul 2013

    All-Optical EXOR for Cryptographic Application Based on Spatial Solitons

    Spatial solitons are optical beams that propagate without changing their shape, thanks to the balance between nonlinear effect (self-focusing) and diffraction. This balance effect has demonstrated to be stable in two-dimensional waveguides. In this paper, the authors present an all-optical EXOR for cryptographic application based on spatial soliton beams. The...

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  • White Papers // Jul 2013

    Diffusion Analysis of Message Expansion in STITCH-256

    Cryptographic hash functions are built up from individual components, namely pre-processing, step transformation, and final processing. Some of the hash functions, such as SHA-256 and STITCH-256, employ non-linear message expansion in their pre-processing stage. However, STITCH-256 was claimed to produce high diffusion in its message expansion. In a cryptographic algorithm,...

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  • White Papers // Jul 2013

    Design and Simulation of a PIFA Antenna for the Use in 4G Mobile Telecommunications Networks

    In this paper, the authors describe the design and simulation by HFSS simulator of a probe-fed and multi-band Planar Inverted-F Antenna (PIFA) for the 4G mobile networks. The antenna works in 8 bands. Five bands are auctioned by FCC for 4G (LTE and WiMax) such 710 MHz, 1900 MHz (PCS),...

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  • White Papers // Jun 2013

    Vertical Handover Management for VoIP Session over Broadband Wireless Networks

    Today, wireless LAN (IEEE 802.11g/n) has been the dominant wireless network that can provide high data rates in a limited coverage area. While emerging mobile WiMAX (IEEE 802.16e) can provide a wireless broadband access to mobile users in a wide coverage area. These two different technologies will co-exist while complementing...

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  • White Papers // Jun 2013

    Energy Saving in WSN with Directed Connectivity

    Wireless Sensor Networks have been implemented in many indoor applications such as offices, hospitals, laboratories for monitoring the parameters such as temperature, humidity etc. Most of the applications have used omnidirectional antennas. In randomly deployed ad hoc wireless sensor networks, this may be useful to achieve coverage and connectivity with...

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  • White Papers // Jun 2013

    OMT-G Modeling and Cloud Implementation of a Reference Database of Addressing in Morocco

    A reference database of addressing is an important resource for urban applications. The efficiency of an addressing sys-tem depends on both data quality and technical architecture. Data must respect a standard model that is flexible to meet different cases in the field. The technical architecture should be service oriented to...

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  • White Papers // Jun 2013

    An Efficient Approach for Agile Web Based Project Estimation: AgileMOW

    There exist numerous sophisticated models and methods for estimating the size, cost and schedule of software projects. However, the ability to accurately predict the software cost of web based software for agile software projects is still dubious. The most appropriate web based software cost estimation in an agile software development...

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  • White Papers // Jun 2013

    Opportunistic Unicast and Multicast Routing Protocol for VANET

    Vehicular Ad hoc NETwork (VANET) is a new paradigm of wireless network. Reliable and efficient unicast and multi-cast routing protocols are critical for VANETs. As a possible solution, Opportunistic Routing (OR) has received much attention recently. This paper focuses on the aspect of soft security by building trust opportunistic forwarding...

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  • White Papers // Feb 2013

    Traffic-Distributed Clustering Scheme for Cluster-Based WSNs with Various Non-Uniform Traffic Fluctuations

    In Wireless Sensor Networks (WSNs), it is essential to save energy consumption at Sensor Nodes (SNs). A clustering technique is one of the approaches to save energy consumption, where several neighboring SNs form a cluster and transmit the sensed data to their Cluster Head (CH), and then the CH sends...

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  • White Papers // Jan 2013

    Public-Key Cryptosystems with Secret Encryptor and Digital Signature

    In this paper, the authors describe and compares a variety of algorithms for secure transmission of information via open communication channels based on the discrete logarithm problem that do not require search for a generator (primitive element). Modifications that simplify the cryptosystem are proposed, and, as a result, accelerate its...

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  • White Papers // Jan 2013

    Hybrid Real-Time and Preset Processing for Indoor Radio Geo-Location in Dense Multipath Environments

    The existence of various geo-location applications and their accuracy requirements enhance the necessities for suitable processing techniques to solve the indoor geo-location problems. Since, Impulse Radio Ultra-WideBand (IR-UWB) signals have very short duration pulses; they can provide very accurate ranging and geo-location capability in short range indoor radio propagation environments....

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  • White Papers // Jan 2013

    Optimizing Operating Cost of an Intrusion Detection System

    Very often it so happens that the cost of operating an Intrusion Detection System (IDS) exceeds the cost of purchasing the IDS itself. In such cases, regular operation and maintenance of the system becomes expensive. Thus, it becomes essential to reduce the operating cost of the IDS without compromising on...

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  • White Papers // Jan 2013

    A Novel Decoder Based on Parallel Genetic Algorithms for Linear Block Codes

    Genetic algorithms offer very good performances for solving large optimization problems, especially in the domain of error-correcting codes. However, they have a major drawback related to the time complexity and memory occupation when running on a uniprocessor computer. This paper proposes a parallel decoder for linear block codes, using Parallel...

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  • White Papers // Dec 2012

    Research of Web Real-Time Communication Based on Web Socket

    Regarding the limitations of traditional web real-time communication solutions such as polling, long-polling, flash plug-in, propose that using new coming Web Socket technology in the web real-time communication field, introduce the features of web socket technology, analysis the difference between web socket protocol and HTTP protocol, offer an approach to...

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  • White Papers // Jul 2009

    The Study on the Hierarchy of Internet Router-Level Topology

    Being a huge system, Internet topology structure is very complex. It can't be treated as a plane simply, and its hierarchy must be analyzed. The authors used the k-core decomposition to disentangle the hierarchical structure of Internet Router-Level Topology. By analyzing the router-lever Internet topology measuring data from CAIDA (The...

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  • White Papers // Jul 2009

    Adaptive Backoff Algorithm for IEEE 802.11 MAC Protocol

    A Mobile Ad-hoc NETwork (MANET) is a collection of mobile nodes that can communicate directly over wireless media, without the need for a pre-configured infrastructure. Several approaches have been suggested to improve Quality of Service (QoS) in IEEE 802.11-based MANETs through modifying some of the IEEE 802.11 Medium Access Control...

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  • White Papers // Aug 2009

    Performance Analysis of the D-STTD Communication System with AMC Scheme

    In this paper, the authors propose a Double-Space Time Transmit Diversity (D-STTD) communication system with Adaptive Modulation and Coding (AMC) scheme and analyze its performance using simulation experiments. The simulation results show that the probability of selecting a high Modulation and Coding Scheme (MCS) level increased as the Signal to...

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  • White Papers // Aug 2009

    TDTL Based Frequency Synthesizers with Auto Sensing Technique

    In this paper, the authors presents a frequency synthesizer architecture based on the Time delay Digital Tanlock Loop (TDTL). The loop is of the first order type. The synthesizer architecture includes an adaptation mechanism to keep the complete system in lock. The mechanism uses a frequency sensing structure to control...

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  • White Papers // Aug 2009

    A Novel Blind Channel Estimation for a 2x2 MIMO System

    A novel blind channel estimation method based on a simple coding scheme for a 2 by 2 Multiple-Input Multiple-Output (MIMO) system is described. The proposed algorithm is easy to implement in comparison with conventional blind estimation algorithms, as it is able to recover the channel matrix without performing Singular Value...

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  • White Papers // Aug 2009

    Iterative Detection and Decoding with PIC Algorithm for MIMO-OFDM Systems

    In multipath environments, Multiple-Input Multiple-Output wireless communication system can increase spectral efficiency. Furthermore, to achieve high data rate wireless communications, space-time communication systems need to be in wideband frequency selective channels. In this paper, the authors propose a new iterative detection and decoding scheme based on Parallel Interference Cancel (PIC)...

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  • White Papers // Aug 2009

    Research on Error's Distribution in Triangle Location Algorithm

    The error will inevitably appear in triangle location in WSNs (Wireless Sensor Networks), and the analysis of its character is very important for a reliable location algorithm. To research the error in triangle location algorithm, a triangle location model is set up, the condition of the minimal error is got...

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  • White Papers // Aug 2009

    Authentication and Secret Message Transmission Technique Using Discrete Fourier Transformation

    In this paper, a novel technique, Authentication and Secret Message Transmission using Discrete Fourier Transformation (ASMTDFT) has been proposed to authenticate an image and also some secret message or image can be transmitted over the network. Instead of direct embedding a message or image within the source image, choosing a...

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  • White Papers // Aug 2009

    Regulation of Queue Length in Router Based on an Optimal Scheme

    Based on the proportionally fair scheme that Kelly proposed to solve the optimization problems for utility function in networks and in order to improve the congestion control performance for the queue in router, the linear and terminal sliding Active Queue Management (AQM) algorithms are designed. Especially in the terminal sliding...

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  • White Papers // Aug 2009

    Notification Services for the Server-Based Certificate Validation Protocol

    The Server-Based Certificate Validation Protocol allows PKI clients to delegate to a server the construction or validation of certification paths. The protocol's specification focuses on the communication between the server and the client and its security. It does not discuss how the servers can efficiently locate the necessary PKI resources...

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  • White Papers // Aug 2009

    Research on Financial Distress Prediction with Adaptive Genetic Fuzzy Neural Networks on Listed Corporations of China

    To design a multi-population adaptive genetic BP algorithm, crossover probability and mutation probability are self-adjusted according to the standard deviation of population fitness in this paper. Then a hybrid model combining fuzzy neural network and multi-population adaptive genetic BP algorithm - Adaptive Genetic Fuzzy Neural Network (AGFNN) is proposed to...

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  • White Papers // Aug 2009

    Enhancing Delay in MANET Using OLSR Protocol

    The performance of a Mobile Ad-hoc NEtwork (MANET) is closely related to the capability of the implemented routing protocol to adapt itself to unpredictable changes of topology network and link status. The Optimized Link State Routing (OLSR) protocol is a one key of the proactive routing protocols for MANETs. It...

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  • White Papers // Aug 2009

    Network Delay Model for Overlay Network Application

    The network delay measurement in large scale overlay system become impossible due to the Internet expansion. So, in this paper, the authors introduce a method of modeling network delay with AS and geographic distance. This paper presents a method to model network delay for overlay network application. The network topology...

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  • White Papers // Aug 2009

    Load Control for Overloaded MPLS/DiffServ Networks during SLA Negotiation

    In end-to-end QoS provisioning some bandwidth portions on the link may be reserved for certain traffic classes (and for particular set of users) so the congestion problem of concurrent flows (traversing the network simultaneously) can appear. It means that in overloaded and poorly connected MPLS/DS networks the CR (Constraint-based Routing)...

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  • White Papers // Sep 2009

    Efficient Bandwidth and Power Allocation Algorithms for Multiuser MIMO-OFDM Systems

    In this paper, the authors studies the problem of finding an effective subcarrier and power allocation strategy for downlink communication to multiple users in a MIMO-OFDM system with zero-forcing beamforming. The problem of minimizing total power consumption with constraint on transmission rate for users is formulated. The problem of joint...

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  • White Papers // Sep 2009

    Beam Pattern Scanning (BPS) versus Space-Time Block Coding (STBC) and Space-Time Trellis Coding (STTC)

    In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, Space-Time Block Coding (STBC) and Space-Time Trellis Coding (STTC). In BPS (also called Beam Pattern oScillation), controlled time varying weight vectors are applied to the antenna array elements mounted at...

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  • White Papers // Sep 2009

    Rain Attenuation Impact on Performance of Satellite Ground Stations for Low Earth Orbiting (LEO) Satellites in Europe

    Low Earth Orbits (LEO) satellites are used for public communication and for scientific purposes. These satellites provide opportunities for investigations for which alternative techniques are either difficult or impossible to apply. Ground stations have to be established in order to communicate with such satellites. Usually these satellites communicate with ground...

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  • White Papers // Sep 2009

    Detection, Identification and Tracking of Flying Objects in Three Dimensions Using Multistatic Radars

    Now-a-days, most of radars are monostatic in which one antenna or a pair of antennas positioned at the same point is used for transmitting and receiving electromagnetic waves. Multistatic radar systems can be used in many applications such as homeland security, anti-air defense, anti-missile defense, ship's navigation and traffic control...

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  • White Papers // Sep 2009

    Investigation into the Performance of a MIMO System Equipped with ULA or UCA Antennas: BER, Capacity and Channel Estimation

    In this paper, the authors reports on investigations into the performance of a Multiple Input Multiple Output (MIMO) wireless communication system employing a Uniform Linear Array (ULA) at the transmitter and either a Uniform Linear Array (ULA) or a Uniform Circular Array (UCA) antenna at the receiver. The transmitter is...

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  • White Papers // Sep 2009

    Two-Dwell Synchronization Techniques and Mimo Systems for Performance Improvements of 3G Mobile Communications

    In this paper, the authors considers the case of smart antennas and Multiple-Inputs Multiple-Outputs (MIMO) systems, suited for the radio access of 3G mobile communications, involving two-dimensional spatio-temporal signal processing and two-dwell procedures. The main novelty of their work is twofold: first, a two-dwell acquisition technique is here performed to...

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  • White Papers // Sep 2009

    A Scalable Architecture for Network Traffic Monitoring and Analysis Using Free Open Source Software

    The lack of current network dynamics studies that evaluate the effects of new application and protocol deployment or long-term studies that observe the effect of incremental changes on the Internet, and the change in the overall stability of the Internet under various conditions and threats has made network monitoring challenging....

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  • White Papers // Sep 2009

    A Trust Model Based on the Multinomial Subjective Logic for P2P Network

    In order to deal with the problems in P2P systems such as unreliability of the Service, security risk and attacks caused by malicious peers, a novel trust model MSL-TM based on the multinomial subjective logic is proposed. The model uses multinomial ratings and Dirichlet distribution to compute the expectation of...

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  • White Papers // Sep 2009

    A Novel Packet Switch Node Architecture for Contention Resolution in Synchronous Optical Packet Switched Networks

    Packet contention is a key issue in Optical Packet Switch (OPS) networks and finds a viable solution by including optical buffering techniques incorporating Fiber Delay Lines (FDLs) in the switch architecture. The present paper proposes a novel switch architecture for packet contention resolution in synchronous OPS network employing the packet...

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  • White Papers // Sep 2009

    A Network Intrusion Detection Model Based on Immune Multi-Agent

    A new network intrusion detection model based on immune multi-agent theory is established and the concept of multi-agents is advanced to realize the logical structure and running mechanism of immune multi-agent as well as multi-level and distributed detection mechanism against network intrusion, using the adaptability, diversity and memory properties of...

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  • White Papers // Sep 2009

    A Low Power and High Speed Viterbi Decoder Based on Deep Pipelined, Clock Blocking and Hazards Filtering

    A high speed and low power Viterbi decoder architecture design based on deep pipelined, clock gating and toggle filtering has been presented in this paper. The Add-Compare-Select (ACS) and Trace Back (TB) units and its sub circuits of the decoder have been operated in deep pipelined manner to achieve high...

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  • White Papers // Oct 2009

    A Scalable Architecture Supporting QoS Guarantees Using Traffic Engineering and Policy Based Routing in the Internet

    The study of Quality of Service (QoS) has become of great importance since the Internet is used to support a wide variety of new services and applications with its legacy structure. Current Internet architecture is based on the Best Effort (BE) model, which attempts to deliver all traffic as soon...

    Provided By Scientific Research

  • White Papers // Oct 2009

    Performance Analysis of a Novel Dual-Frequency Multiple Access Relay Transmission Scheme

    In this paper, the authors present the performance analysis of a novel channel assignment scheme where two non-cooperative independent users simultaneously communicate with their destination through a single relay by using only two frequency channels. The analytic derivation of the probability of symbol error for two main relay techniques will...

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  • White Papers // Oct 2009

    Research on the Active DDoS Filtering Algorithm Based on IP Flow

    Distributed Denial-of-Service (DDoS) attacks against public web servers are increasingly common. Countering DDoS attacks are becoming ever more challenging with the vast resources and techniques increasingly available to attackers. It is impossible for the victim servers to work on the individual level of on-going traffic flows. In this paper, the...

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  • White Papers // Mar 2013

    An Ad-Hoc Low Cost Wireless Sensor Network for Smart Gas Metering

    The monitoring of power consumption has become of a great interest in recent years as well as the innovative technologies available to realize Wireless Sensor Networks (WSNs) have experienced a great growth. While smart metering technologies for electric energy are already established, as sensors power supply comes directly from power...

    Provided By Scientific Research

  • White Papers // Sep 2009

    TCP-R with EPDN: Handling out of Order Packets in Error Prone Satellite Networks

    In this paper, the authors have shown that packet reordering is common, especially in satellite networks where there are link level retransmissions and multipath routing. Moreover, traditional satellite networks exhibit high corruption rates causing packet losses. Reordering and corruption of packets decrease the TCP performance of a network, mainly because...

    Provided By Scientific Research

  • White Papers // Feb 2009

    Game Theoretic Analysis of Joint Rate and Power Allocation in Cognitive Radio Networks

    Spectrum sharing is an essential enabling functionality to allow the coexistence between Primary User (PU) and Cognitive Users (CUs) in the same frequency band. In this paper, the authors consider joint rate and power allocation in cognitive radio networks by using game theory. The optimum rates and powers are obtained...

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  • White Papers // Feb 2009

    Synchronous Dynamic Adjusting: An Anti-Collision Algorithm for an RF-UCard System

    An RF-UCard system is a contactless smartcard system with multiple chip operating systems and multiple applications. A multi-card collision occurs when more than one card within the reader's read field and thus lowers the efficiency of the system. This paper presents a novel and enhanced algorithm to solve the multi-card...

    Provided By Scientific Research

  • White Papers // Feb 2009

    Performance Analysis of Sub-Rating for Handoff Calls in HCN

    Hierarchical Cellular Networks (HCN) offer more efficient channel utilization and better Quality of Service (QoS) under the high tele-traffic condition compared to the single-tier system. One of the important measures of QoS in HCN as in any single-tier system is the handoff dropping rate. Although the existing approaches such as...

    Provided By Scientific Research

  • White Papers // Feb 2009

    On the Scalable Fairness and Efficient Active Queue Management of RED

    Internet routers generally see packets from a fast flow more often than a slow flow. This suggests that network fairness may be improved without per-flow information. In this paper, the authors propose a scheme using Most Recently Used List (MRUL)-a list storing statistics of limited active flows that sorted in...

    Provided By Scientific Research