Crown

Displaying 1-40 of 57 results

  • White Papers // Jun 2013

    HGrid: A Data Model for Large Geospatial Data Sets in HBase

    Cloud-based infrastructures enable applications to collect and analyze massive amounts of data. Whether these applications are newly developed or they are being evolved from existing RDBMS-based implementations, NoSQL databases offer an attractive platform with which to address this challenge. However, developers find it difficult to effectively manage data in NoSQL...

    Provided By Crown

  • White Papers // Dec 2012

    A Three-Dimensional Data Model in HBase for Large Time-Series Dataset Analysis

    In the transition of applications from the traditional enterprise infrastructures to cloud infrastructures, scalable database management system plays an important role in efficiently managing and analyzing unprecedented massive amount of data. Compared to RDBMSs, NoSQL databases are more attractive in addressing this challenge. However, it is not easy to manage...

    Provided By Crown

  • White Papers // Nov 2012

    Spectral-Energy Efficiency Tradeoff in Multicell Cellular Networks With Adaptive Relay Cooperation

    By observing that the Relay Stations (RSs) will receive a signal replica of the users' transmissions during the broadcast phase, the authors propose an adaptive relay cooperation scheme. The RSs will utilize the readily available signal replica and the additional diversity naturally inherent in them to either perform CO-operative Multi-Point...

    Provided By Crown

  • White Papers // Nov 2012

    LP-Based Optimization of Storage and Retrieval for Distributed Video-on-Demand

    The authors first formulate the optimization problem to an integer program. To address its tractability, they propose a novel, effective and implementable heuristic. The heuristic, termed LP-SR decomposes the problem into two computationally efficient Linear Programs (LPs) for segment storage and retrieval, respectively. The strength of LP-SR is that it...

    Provided By Crown

  • White Papers // Oct 2012

    An Update Model for Network Coding in Cloud Storage Systems

    The fast emerging cloud services have received a tremendous amount of attention in both industry and academia. Storage services such as Dropbox and iCloud enabled one to share files among multiple users or devices. Providing the benefits of network coding in distributed systems such as Peer-to-Peer file sharing and multimedia...

    Provided By Crown

  • White Papers // Aug 2012

    Optimal Matching Between Energy Consumption of Base Stations and Traffic Load in Green Cellular Networks

    Energy efficiency has become significantly important in designing future green mobile communication systems. In this paper, a novel energy efficiency metric, which is per energy per area capacity, is proposed to quantify the matching degree between energy consumption of Base Stations (BSs) and the traffic load. Based on BS power...

    Provided By Crown

  • White Papers // Dec 2011

    BSNet: A Three-Layer Business Service Correlation Network Model

    With the advancement of enterprise information system, Services-Oriented Business Ecosystem (SOBE) has become an important pattern for the organization and management of the massive business services. At the same time, Internet Of Service (IOS) provides a business model in which service vendors and consumers can interactive with each other via...

    Provided By Crown

  • White Papers // Sep 2011

    LLSiWSN: A New Range-Free Localization Algorithm for Large Scale Wireless Sensor Networks

    This paper is proposed a range-free localization algorithm in WSN technology. Effective use some useful information for localization algorithm during sensor node deploy process, to avoid distance-based localization algorithm when in complex environments ranging difficulties, while the same time, avoid the extensive use GPS node of anchor-free localization algorithm with...

    Provided By Crown

  • White Papers // Sep 2011

    An Emerging Concept for 4G+ Wireless Cellular Networks: Terminal Relaying

    The technological foundation of Fourth Generation (4G) cellular systems was outlined in the Long Term Evolution Advanced (LTE-A) standards which enable communication rates of 100 Megabits per second for mobile communications and 1 Gigabit per second for nomadic ones. In LTE-A the deployment of wireless intermediate communication-assisting nodes, known as...

    Provided By Crown

  • White Papers // Aug 2011

    Data Quality Maximization in Sensor Networks With a Mobile Sink

    In this paper, the authors consider a wireless sensor network with a mobile sink moving along a fixed trajectory without stop to collect data. They assume that a few powerful and high-capacity sensors deployed nearby the trajectory are the gateways, which are able to communicate with the sink directly when...

    Provided By Crown

  • White Papers // Jul 2011

    Compressed Sensing Construction of Spectrum Map for Routing in Cognitive Radio Networks

    Cooperative relay enables general multi-hop Cognitive Radio Networks (CRN) over Cognitive Radios (CR) and nodes of Primary System (PS). However, successful CR networking such as routing relies on the knowledge of radio resource availability associated with location, which is a challenge of traditional spectrum sensing. The authors introduce the concept...

    Provided By Crown

  • White Papers // Jun 2011

    CultureBee : A Fully Wireless Monitoring and Control System for Protecting Cultural Heritage

    This paper presents a component based wireless monitoring and control system. The system is introduced from both the system architecture and function point of view. The paper begins with the introduction of the component design and the communication interaction between them. The system is composed by three components, the wireless...

    Provided By Crown

  • White Papers // Apr 2011

    AMPHIBIA: A Cognitive Virtualization Platform for End-to-End Slicing

    To cope with the increasingly diversifying services, QoS, and network architectures, network virtualization is a promising technology that enables the concurrent deployment of multiple network technologies on a shared network. Considering recent advances of wireless technologies, it is crucial to extend virtual networks to wireless domains. The authors refer to...

    Provided By Crown

  • White Papers // Apr 2011

    Closed-Form Expressions for the Exact Cram?r-Rao Bounds of Timing Recovery Estimators From BPSK and Square-QAM Transmissions

    In this paper, the authors derive for the first time analytical expressions for the Cram?r-Rao Lower Bounds (CRLBs) of timing recovery estimators from Binary Phase Shift Keying (BPSK) and square Quadrature Amplitude Modulation (QAM) transmissions. The bounds are derived in the presence of Additive White Gaussian Noise (AWGN). Moreover, the...

    Provided By Crown

  • White Papers // Jan 2011

    Low Power Noise Detection Circuit Utilizing Switching Activity Measurement Method

    Noise often limits the performance of transmitted signals and degrades signals quality. Moreover, stochastic nature of noise makes it difficult to predict, and hence, is hard to detect. In hardware implementation, the reduction of noise can only be optimized in the baseband where complex and intensive computation is executed using...

    Provided By Crown

  • White Papers // Jan 2011

    Behavior-Based Telecom Tariff Service Design With Neural Network Approach

    This paper presents a behavior-based telecommunication tariff service design model. Unlike traditional service design models, which includes demographic attributes to design telecommunication tariff services, this model only uses history data about telecommunication customer behavior, such as voice service usage, text service usage, and multimedia service usage to design new tariff...

    Provided By Crown

  • White Papers // Dec 2010

    Downlink TCP Performance Enhancement at Handoff for FMIPv6-Enabled Nodes

    TCP's downlink performance during FMIPv6- enabled IEEE802.11g handoff is examined. The use of a user initiated Handoff Notification, sent prior to handoff, and is proposed. Therefore, the correspondent node is aware of the handoff induced disruption, hence avoiding dropping the congestion window size and triggering Fast Retransmission mechanisms. During handoff,...

    Provided By Crown

  • White Papers // Oct 2010

    Supporting Periodic, Strong Re-Authentication in MANET Scenarios

    A Security Association (SA), established by strong authentication, between a node pair in a Mobile Ad hoc NETwork (MANET) could be lost when its route is disconnected. In contrast, in good channel conditions and stable topology, routing protocols such as the Optimized Link State Routing (OLSR) do not refresh routes...

    Provided By Crown

  • White Papers // Oct 2010

    Infrastructure for Multi-Level Secure Service-Oriented Architecture (MLS-SOA)

    Service-Oriented Architecture (SOA) is the premier application framework for integrating complex heterogeneous computing systems in business and government. To utilize SOA in sensitive military systems, however, the issue of Multi-Level Security (MLS) must be addressed. MLS requirements call for strict separation and limit interaction between classification levels. However, many Web...

    Provided By Crown

  • White Papers // Oct 2010

    Efficiency of Multiparty Networking Protocols Over Mobile Tactical Radios on VHF Bands

    Multiparty routing protocols for resource constraint VHF Mobile Tactical Networks are studied by employing a modeling platform that integrates VHF tactical radio signal measurement data and practical network deployment scenarios. The standard approach of Simplified Multicast Forwarding based on the 2-hop neighborhood information and a typical alternative using 1-hop network...

    Provided By Crown

  • White Papers // Oct 2010

    A Novel Reduced-Complexity Group Detection Structure in MIMO Frequency Selective Fading Channels

    In this paper a novel reduced complexity detection method named modified symbol flipping method is introduced and its advantages on reducing the burden of the calculations at the receiver compared to the optimum maximum likelihood detection method on multiple input-multiple output frequency selective fading channels are explained. The initial concept...

    Provided By Crown

  • White Papers // Aug 2010

    Adaptive Turbo Trellis Coded Modulation Aided Distributed Space-Time Trellis Coding for Cooperative Communications

    In this contribution, the authors propose an adaptive Turbo Trellis Coded Modulation (TTCM) aided Distributed Space-Time Trellis Coding (STTC) scheme for cooperative communication over quasi-static Rayleigh fading channels. An Adaptive TTCM (ATTCM) scheme is employed by the source node during the first transmission period for reliably conveying the source bits...

    Provided By Crown

  • White Papers // Jul 2010

    Exact Bit Error Rate of MIMO MRC Systems With Cochannel Interference and Rayleigh Fading

    In this paper, the authors present a new method for deriving exact expressions for the average Bit Error Rate (BER) of Multiple-Input Multiple-Output (MIMO) wireless systems with transmit beamforming and Maximal Ratio Combining (MRC) reception, known as MIMO MRC, in the presence of co-channel interference. It is assumed that both...

    Provided By Crown

  • White Papers // Jun 2010

    A Lightweight Currency-Based P2P VoD Incentive Mechanism

    Users in a Peer-To-Peer Video on Demand (P2P VoD) system are allowed to watch any video file at any point in time and to use VCR operations like fast forward, rewind and pause at any time, which decreases their ability to help each other and offload the server. Encouraging peers...

    Provided By Crown

  • White Papers // Jun 2010

    Linear Minimum Mean-Squared Error Channel Estimation for Per-Subcarrier Antenna Selection

    The linear minimum Mean-Squared Error (MSE) channel estimator for systems employing per-subcarrier transmit antenna selection is developed. It is shown that the frequency domain correlations after the selection process is approximated well using a simple explicit function. Performance of resultant estimators, which assume a certain correlation model, deteriorates quickly at...

    Provided By Crown

  • White Papers // Jun 2010

    Distributed Source-Coding, Channel-Coding and Modulation for Cooperative Communications

    In this contribution, the authors propose a novel Distributed Source-coding, Channel-coding and Modulation (DSCM) scheme for cooperative communications. The proposed DSCM scheme is designed for ensuring the decoding convergence of its constituent component codes, namely, the Variable Length Code (VLC) and two Coded Modulation (CM) schemes. The source node encodes...

    Provided By Crown

  • White Papers // May 2010

    A DSL-Based Approach to Software Development and Deployment on Cloud

    With the advent of Cloud computing massively scalable and cost effective IT resources can be accessed and used seamlessly. Various APIs are made available for manipulating the infrastructure of the Cloud and its data models and for applying the deployment tools. Cloud computing promotes a new approach to software development....

    Provided By Crown

  • White Papers // Apr 2010

    An Optimum Network Selection Solution for Multihomed Hosts Using Hopfield Networks

    The interworking of heterogeneous network technologies to provide improved coverage and QoS differentiation has attracted some interest within the community. Within 3GPP, some work has focused on the interworking between 3G and 2G and also Wireless LAN (WLAN) systems. Within the IEEE, a Layer 2 triggering mechanism for intersystem handoff,...

    Provided By Crown

  • White Papers // Mar 2010

    Cyber Crime Strategy

    The Cyber Security Strategy identifies criminal use of cyber space as one of the three principal threats to cyber security alongside state and terrorist use. This paper sets out the Home Office's approach to tackling cyber crime, showing how the authors will tackle such crimes directly through the provision of...

    Provided By Crown

  • White Papers // Mar 2010

    A Novel Ray Analogy for Enrolment of Ear Biometrics

    The ear is a maturing biometric with qualities that give it superiority over other biometrics in a number of situations; in particular the ear is relatively immune to variation due to ageing. Successful ear biometrics rely upon a well enrolled dataset, with ears normalised for position, scale and rotation. The...

    Provided By Crown

  • White Papers // Mar 2010

    On Using Gait Biometrics to Enhance Face Pose Estimation

    Many face biometrics systems use controlled environments where subjects are viewed directly facing the camera. This is less likely to occur in surveillance environments, so a process is required to handle the pose variation of the human head, change in illumination, and low frame rate of input image sequences. This...

    Provided By Crown

  • White Papers // Mar 2010

    Interactive Quality-Driven Feedback for Biometric Systems

    The application of biometric technology has so far been top-down, driven by governments and law enforcement agencies. The low demand of this technology from the public, despite its many advantages compared to the traditional means of authentication is probably due to the lack of human factor considerations in the design...

    Provided By Crown

  • White Papers // Mar 2010

    HeartID: Cardiac Biometric Recognition

    This paper examines the applicability of cardiac signals for biometric recognition. Two physiological signals are considered, namely the Electrocardiogram (ECG) and the Phonocardiogram (PCG) as it has been shown they bare adequate discriminative information in a population. Due to the idiosyncratic properties of ECG and PCG, individual algorithms are developed...

    Provided By Crown

  • White Papers // Mar 2010

    An Expression Transformation for Improving the Recognition of Expression-Variant Faces From One Sample Image Per Person

    It is known that when only one sample image per gallery person is available, as a result of the small sample size problem, the recognition performance of discriminant feature extraction methods substantially degrades. This is particularly the case when the images are under drastic facial expression variation. To address this...

    Provided By Crown

  • White Papers // Mar 2010

    Facial Feature Localization Using Graph Matching With Higher Order Statistical Shape Priors and Global Optimization

    This paper presents a graphical model for deformable face matching and landmark localization under an unknown non-rigid warp. The proposed model learns and combines statistics of both appearance and shape variations of facial images (learnt purely from a set of frontal training images) in a complex objective function in an...

    Provided By Crown

  • White Papers // Mar 2010

    The Effect of Time on the Performance of Gait Biometrics

    Many studies have shown that it is possible to recognize people by the way they walk. However, there are a number of covariate factors that affect recognition performance. The time between capturing the gallery and the probe has been reported to affect recognition the most. To date, no study has...

    Provided By Crown

  • White Papers // Mar 2010

    Local Ordinal Contrast Pattern Histograms for Spatiotemporal, Lip-Based Speaker Authentication

    The lip-region can be interpreted as either a genetic or behavioral biometric trait depending on whether static or dynamic information is used. Despite this breadth of possible application as a biometric, lip-based biometric systems are scarcely developed in scientific literature compared to other more popular traits such as face or...

    Provided By Crown

  • White Papers // Mar 2010

    Performance of Multi-Hop Whisper Cognitive Radio Networks

    In 2003, Federal Communications Commission (FCC) has released a new spectrum policy called "Interference temperature model" to improve the channel access opportunities of secondary users. Under this model, the secondary users are allowed to access the licensed spectrum simultaneously with the primary users provided that the interference at the primary...

    Provided By Crown

  • White Papers // Mar 2010

    Spectrum Aware Opportunistic Routing in Cognitive Radio Networks

    Cognitive Radio (CR) emerges as a key technology to enhance spectrum efficiency and thus creates opportunistic transmissions over links. Supporting the routing function on top of numerous opportunistic links is a must to route packets in a general Cognitive Radio Network (CRN) consisting of multi-radio systems. However, there lacks complete...

    Provided By Crown

  • White Papers // Mar 2010

    Information Epidemics in Complex Networks With Opportunistic Links and Dynamic Topology

    Wireless networks, especially Mobile Ad hoc NETworks (MANET) and Cognitive Radio Networks (CRN), are facing two new challenges beyond traditional random network model: opportunistic links with random nature due to fading and dynamic channel access, and dynamic network topology due to mobility and time varying. For a more general networking...

    Provided By Crown

  • White Papers // Nov 2012

    Spectral-Energy Efficiency Tradeoff in Multicell Cellular Networks With Adaptive Relay Cooperation

    By observing that the Relay Stations (RSs) will receive a signal replica of the users' transmissions during the broadcast phase, the authors propose an adaptive relay cooperation scheme. The RSs will utilize the readily available signal replica and the additional diversity naturally inherent in them to either perform CO-operative Multi-Point...

    Provided By Crown

  • White Papers // Dec 2010

    Downlink TCP Performance Enhancement at Handoff for FMIPv6-Enabled Nodes

    TCP's downlink performance during FMIPv6- enabled IEEE802.11g handoff is examined. The use of a user initiated Handoff Notification, sent prior to handoff, and is proposed. Therefore, the correspondent node is aware of the handoff induced disruption, hence avoiding dropping the congestion window size and triggering Fast Retransmission mechanisms. During handoff,...

    Provided By Crown

  • White Papers // Apr 2010

    An Optimum Network Selection Solution for Multihomed Hosts Using Hopfield Networks

    The interworking of heterogeneous network technologies to provide improved coverage and QoS differentiation has attracted some interest within the community. Within 3GPP, some work has focused on the interworking between 3G and 2G and also Wireless LAN (WLAN) systems. Within the IEEE, a Layer 2 triggering mechanism for intersystem handoff,...

    Provided By Crown

  • White Papers // Oct 2010

    A Novel Reduced-Complexity Group Detection Structure in MIMO Frequency Selective Fading Channels

    In this paper a novel reduced complexity detection method named modified symbol flipping method is introduced and its advantages on reducing the burden of the calculations at the receiver compared to the optimum maximum likelihood detection method on multiple input-multiple output frequency selective fading channels are explained. The initial concept...

    Provided By Crown

  • White Papers // Mar 2004

    The Effects of Computer Games on Young Children - A Review of the Research

    This review has considered various studies which have investigated the effects of computer games on young children and which have found there to be both positive and negative consequences. Little research has been carried out into non-arcade electronic game playing as this was originally perceived as a harmless and enjoyable...

    Provided By Crown

  • White Papers // Aug 2001

    Development of Cordwood Boiler System

    Wood fuel heating has usually been by means of logs, these being produced from woodlands by crosscutting and splitting. This is often in the form of open fires or wood burning stoves. In some cases these provide a full heat supply for the building. This is where the benefits of...

    Provided By Crown

  • White Papers // Aug 2001

    Risk Assessment for Fish Passage Through Small, Low-Head Turbines

    This paper discusses and provides information about Low-Head Turbines. Small, low-head run-of river hydroelectric sites are often perceived as potentially damaging to fisheries interests, especially on migratory salmonid rivers. One of the main risks occurs during the downstream migration phase of salmonid smolts (mainly spring) and parr (mainly autumnal), as...

    Provided By Crown

  • White Papers // Feb 2003

    Prolongation of the Deployment and Monitoring of a Multiple Oscillating Water Column Wave Energy Converter

    This paper gives a brief background to the origins of the prototype device and presents the methodology for the analysis of the prototype conversion efficiency, calculated for the period of the sea trials as 34.5%. The prolongation of the sea trials period allowed the generation of physical data from which...

    Provided By Crown

  • White Papers // Jun 2001

    An Evaluation of Herbicides for Post-Emergence Use in Short Rotation Coppice

    The objective of this paper was to evaluate the safety and efficacy of a range of herbicides and mixtures of herbicides, with both contact and residual activity, for the post-emergence control of weeds in newly planted willow short rotation coppice (SRC). One of the most common causes of SRC crop...

    Provided By Crown

  • White Papers // Jan 2003

    A Further Evaluation of Herbicides for Post-Emergence Use in Short Rotation Coppice

    The objective of this paper was to evaluate the safety and efficacy of a range of herbicides and mixtures of herbicides, with both contact and residual activity, for the post-emergence control of weeds in newly planted willow short rotation coppice (SRC). One of the most common causes of SRC crop...

    Provided By Crown

  • White Papers // Mar 2010

    Cyber Crime Strategy

    The Cyber Security Strategy identifies criminal use of cyber space as one of the three principal threats to cyber security alongside state and terrorist use. This paper sets out the Home Office's approach to tackling cyber crime, showing how the authors will tackle such crimes directly through the provision of...

    Provided By Crown

  • White Papers // Sep 2009

    Policies for Self Tuning Home Networks

    A Home Network (HN) is usually managed by a user who does not possess knowledge and skills required to perform management tasks. When abnormalities are detected, it is desirable to let the network tune itself under the direction of certain policies. However, self tuning tasks usually require coordination between several...

    Provided By Crown

  • White Papers // Dec 2008

    A Transmodel Based XML Schema for the Google Transit Feed Specification With a GTFS / Transmodel Comparison

    This paper compares the Google Transit Feed Specification (GTFS) with then equivalent elements from Transmodel and then out lines a proposal to create a Transmodel based XML schema for exchanging transit stop and timetable data. The schema would be fully compatible and interoperable with both Google s GTFS and Transmodel...

    Provided By Crown

  • White Papers // Feb 2010

    Practitioner Guide: How To Create A Talent Management Strategy That Reflects Diversity

    This paper is for HR professionals rather than at line or senior managers. It will give the ideas on how to communicate with and influence senior managers, line managers and staff. Appendix A gives some background on the origin of this paper. Every talent management approach is affected by the...

    Provided By Crown

  • White Papers // May 2010

    A DSL-Based Approach to Software Development and Deployment on Cloud

    With the advent of Cloud computing massively scalable and cost effective IT resources can be accessed and used seamlessly. Various APIs are made available for manipulating the infrastructure of the Cloud and its data models and for applying the deployment tools. Cloud computing promotes a new approach to software development....

    Provided By Crown

  • White Papers // Mar 2010

    A Novel Ray Analogy for Enrolment of Ear Biometrics

    The ear is a maturing biometric with qualities that give it superiority over other biometrics in a number of situations; in particular the ear is relatively immune to variation due to ageing. Successful ear biometrics rely upon a well enrolled dataset, with ears normalised for position, scale and rotation. The...

    Provided By Crown

  • White Papers // Mar 2010

    On Using Gait Biometrics to Enhance Face Pose Estimation

    Many face biometrics systems use controlled environments where subjects are viewed directly facing the camera. This is less likely to occur in surveillance environments, so a process is required to handle the pose variation of the human head, change in illumination, and low frame rate of input image sequences. This...

    Provided By Crown

  • White Papers // Mar 2010

    Interactive Quality-Driven Feedback for Biometric Systems

    The application of biometric technology has so far been top-down, driven by governments and law enforcement agencies. The low demand of this technology from the public, despite its many advantages compared to the traditional means of authentication is probably due to the lack of human factor considerations in the design...

    Provided By Crown

  • White Papers // Mar 2010

    HeartID: Cardiac Biometric Recognition

    This paper examines the applicability of cardiac signals for biometric recognition. Two physiological signals are considered, namely the Electrocardiogram (ECG) and the Phonocardiogram (PCG) as it has been shown they bare adequate discriminative information in a population. Due to the idiosyncratic properties of ECG and PCG, individual algorithms are developed...

    Provided By Crown

  • White Papers // Mar 2010

    An Expression Transformation for Improving the Recognition of Expression-Variant Faces From One Sample Image Per Person

    It is known that when only one sample image per gallery person is available, as a result of the small sample size problem, the recognition performance of discriminant feature extraction methods substantially degrades. This is particularly the case when the images are under drastic facial expression variation. To address this...

    Provided By Crown

  • White Papers // Mar 2010

    Facial Feature Localization Using Graph Matching With Higher Order Statistical Shape Priors and Global Optimization

    This paper presents a graphical model for deformable face matching and landmark localization under an unknown non-rigid warp. The proposed model learns and combines statistics of both appearance and shape variations of facial images (learnt purely from a set of frontal training images) in a complex objective function in an...

    Provided By Crown

  • White Papers // Mar 2010

    The Effect of Time on the Performance of Gait Biometrics

    Many studies have shown that it is possible to recognize people by the way they walk. However, there are a number of covariate factors that affect recognition performance. The time between capturing the gallery and the probe has been reported to affect recognition the most. To date, no study has...

    Provided By Crown

  • White Papers // Sep 2009

    Adaptive Client-Impostor Centric Score Normalization: A Case Study in Fingerprint Verification

    Cohort-based score normalization as exemplified by the T-norm (for Test normalization) has been the state-of the-art approach to account for the variability of signal quality in testing. On the other hand, user-specific score normalization such as the Z-norm and the F-norm, designed to handle variability in performance across different reference...

    Provided By Crown

  • White Papers // Sep 2009

    Fingerprint Recognition Performance in Rugged Outdoors and Cold Weather Conditions

    This paper reports on tests of the performance of fingerprint recognition technology in rugged outdoor conditions, with an especial concentration on the performance in cold weather. The authors analyze: Chip versus optical fingerprint scanner technology, recognition performance and image quality, and user/device interaction. A outdoor fingerprint door access system was...

    Provided By Crown

  • White Papers // Mar 2010

    Local Ordinal Contrast Pattern Histograms for Spatiotemporal, Lip-Based Speaker Authentication

    The lip-region can be interpreted as either a genetic or behavioral biometric trait depending on whether static or dynamic information is used. Despite this breadth of possible application as a biometric, lip-based biometric systems are scarcely developed in scientific literature compared to other more popular traits such as face or...

    Provided By Crown

  • White Papers // Dec 2009

    On Decoding, Mutual Information, and Antenna Selection Diversity for Quasi-Orthogonal STBC With Minimum Decoding Complexity

    ABBA codes are an important class of quasi orthogonal space-time block codes proposed by Tirkkonen et al.. Recently, they have become more attractive for practical applications because Yuen et al. have shown that ABBA codes allow pair-wise real-symbol decoding (or equivalently, single-complex symbol decoding) complexity; it is the Minimum Decoding...

    Provided By Crown

  • White Papers // Dec 2009

    Joint Frame Synchronization and Carrier Frequency Offset Estimation in Multicarrier Systems

    Orthogonal Frequency Division Multiplexing (OFDM) is an effective technique to combat multipath fading,. In OFDM, the insertion of a guard interval between symbol blocks called Cyclic Prefix (CP) mitigates Inter-Symbol Interference (ISI). OFDM has been adopted as the modulation scheme for a DAB (Digital Audio Broadcasting) system, ADSL (Asymmetry Digital...

    Provided By Crown

  • White Papers // Dec 2009

    Performance Analysis and Optimal Signal Designs for Minimum Decoding Complexity ABBA Codes

    ABBA codes, a class of Quasi-orthogonal Space-Time Block Codes (QSTBC), have been proposed to increase the code rate of Orthogonal Space-Time Block Codes (OSTBC). Since ABBA QSTBC have low complexity pair-wise complex-symbol decoding and performs better than OSTBC, they have been widely studied for coherent and noncoherent transmissions, beamforming, and...

    Provided By Crown

  • White Papers // Jun 2010

    A Lightweight Currency-Based P2P VoD Incentive Mechanism

    Users in a Peer-To-Peer Video on Demand (P2P VoD) system are allowed to watch any video file at any point in time and to use VCR operations like fast forward, rewind and pause at any time, which decreases their ability to help each other and offload the server. Encouraging peers...

    Provided By Crown

  • White Papers // Jan 2011

    Behavior-Based Telecom Tariff Service Design With Neural Network Approach

    This paper presents a behavior-based telecommunication tariff service design model. Unlike traditional service design models, which includes demographic attributes to design telecommunication tariff services, this model only uses history data about telecommunication customer behavior, such as voice service usage, text service usage, and multimedia service usage to design new tariff...

    Provided By Crown

  • White Papers // Sep 2011

    LLSiWSN: A New Range-Free Localization Algorithm for Large Scale Wireless Sensor Networks

    This paper is proposed a range-free localization algorithm in WSN technology. Effective use some useful information for localization algorithm during sensor node deploy process, to avoid distance-based localization algorithm when in complex environments ranging difficulties, while the same time, avoid the extensive use GPS node of anchor-free localization algorithm with...

    Provided By Crown

  • White Papers // Sep 2011

    An Emerging Concept for 4G+ Wireless Cellular Networks: Terminal Relaying

    The technological foundation of Fourth Generation (4G) cellular systems was outlined in the Long Term Evolution Advanced (LTE-A) standards which enable communication rates of 100 Megabits per second for mobile communications and 1 Gigabit per second for nomadic ones. In LTE-A the deployment of wireless intermediate communication-assisting nodes, known as...

    Provided By Crown

  • White Papers // Jun 2011

    CultureBee : A Fully Wireless Monitoring and Control System for Protecting Cultural Heritage

    This paper presents a component based wireless monitoring and control system. The system is introduced from both the system architecture and function point of view. The paper begins with the introduction of the component design and the communication interaction between them. The system is composed by three components, the wireless...

    Provided By Crown

  • White Papers // Jul 2010

    Exact Bit Error Rate of MIMO MRC Systems With Cochannel Interference and Rayleigh Fading

    In this paper, the authors present a new method for deriving exact expressions for the average Bit Error Rate (BER) of Multiple-Input Multiple-Output (MIMO) wireless systems with transmit beamforming and Maximal Ratio Combining (MRC) reception, known as MIMO MRC, in the presence of co-channel interference. It is assumed that both...

    Provided By Crown

  • White Papers // Aug 2009

    Service Engineering for Inter-Domain Overlay Networks

    In recent years application-level networking (e.g. overlay networks, P2P networks) has become key enabling architecture for supporting distributed services on the Internet. The authors consider overlays to have delay and cost requirements and thus there exists an optimal distribution of the overlay traffic (the service engineering problem) across multi-domain underlay...

    Provided By Crown

  • White Papers // Nov 2012

    LP-Based Optimization of Storage and Retrieval for Distributed Video-on-Demand

    The authors first formulate the optimization problem to an integer program. To address its tractability, they propose a novel, effective and implementable heuristic. The heuristic, termed LP-SR decomposes the problem into two computationally efficient Linear Programs (LPs) for segment storage and retrieval, respectively. The strength of LP-SR is that it...

    Provided By Crown

  • White Papers // Mar 2010

    Performance of Multi-Hop Whisper Cognitive Radio Networks

    In 2003, Federal Communications Commission (FCC) has released a new spectrum policy called "Interference temperature model" to improve the channel access opportunities of secondary users. Under this model, the secondary users are allowed to access the licensed spectrum simultaneously with the primary users provided that the interference at the primary...

    Provided By Crown

  • White Papers // Jun 2010

    Linear Minimum Mean-Squared Error Channel Estimation for Per-Subcarrier Antenna Selection

    The linear minimum Mean-Squared Error (MSE) channel estimator for systems employing per-subcarrier transmit antenna selection is developed. It is shown that the frequency domain correlations after the selection process is approximated well using a simple explicit function. Performance of resultant estimators, which assume a certain correlation model, deteriorates quickly at...

    Provided By Crown

  • White Papers // Jun 2009

    Cooperative Amplify-and-Forward With Trellis Coded Modulation

    In a cooperative communication network, individual users are encouraged not only to transmit their own data, but also relay other user's data. This relaying transmission creates spatial diversity to combat the effect of individual severe fading and path loss. Since cooperative users utilize some degree of their transmission freedom for...

    Provided By Crown

  • White Papers // Mar 2010

    Spectrum Aware Opportunistic Routing in Cognitive Radio Networks

    Cognitive Radio (CR) emerges as a key technology to enhance spectrum efficiency and thus creates opportunistic transmissions over links. Supporting the routing function on top of numerous opportunistic links is a must to route packets in a general Cognitive Radio Network (CRN) consisting of multi-radio systems. However, there lacks complete...

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