University of Delaware

Displaying 1-40 of 44 results

  • White Papers // Mar 2013

    Modeling the Navigation Behavior of Dynamic Web Applications

    In order to manage the growing complexity of web applications, there is a need to abstract and model different system behaviors which simplify the process of analysis, designing, verification, testing and maintenance to improve the quality and reliability of web applications. Navigation of a web application is the sequence of...

    Provided By University of Delaware

  • White Papers // Feb 2013

    Energy-Based Performance Evaluation of Various Routing Protocols in Infrastructure-Less Opportunistic Networks

    Opportunistic networks (Oppnets) provide the communication facilities in the network scenarios where the end-to-end path between the source and the destination never exists or may last only for an unpredictable and very short period of time. The disconnections and re-connections between the nodes are very common in Oppnets. In this...

    Provided By University of Delaware

  • White Papers // Sep 2012

    E-Governance: Past, Present and Future in India

    Online working of a government or providing its services online to its citizens at their door step is known as E-Governance. E-Governance is E-Commerce technology means online availability of government services. The technology and the methods used in E-Governance project provide a roadmap for efficient delivery of services at the...

    Provided By University of Delaware

  • White Papers // Jun 2012

    Optimal Component Selection Problem for Cots Based Software System Under Consensus Recovery Block Scheme: A Goal Programming Approach

    Cost, reliability and time are the three main quality attributes of a software system. Now days much software are designed on COTS component in order to facilitate timely development with reduced cost and improved reliability. Software designed to handle critical control systems have very high reliability requirements. Fault tolerance is...

    Provided By University of Delaware

  • White Papers // May 2012

    Traffic Optimization Through Information Dissemination

    It is a known fact today that VANETs are going to play an increasingly important role in vehicular communication in the future. The impact of these networks especially to solve the problem of traffic optimization and control is significant. Traffic Optimization through Information Dissemination (TOID) is an algorithm based on...

    Provided By University of Delaware

  • White Papers // Feb 2012

    Maximal Throughput Routing in Wireless Linear Networks

    To design an efficient wireless routing scheme, both the physical characteristics of wireless links and the related networking activities must be taken into account. Simply applying the routing algorithms used in wired networks has been shown to be a suboptimal approach because of the fundamental differences between wireless and wired...

    Provided By University of Delaware

  • White Papers // Feb 2012

    Spectral Efficiency of Cooperative Relaying With Imperfect Channel Estimation

    It is well known that cooperative relaying has the potential to improve the performance of end-to-end wireless communications. However, compared to point-to-point communications, implementing cooperative relaying requires much more overhead. For example, more complicated coordination and transmission schemes are required. In this paper, the spectral efficiency of cooperative relaying is...

    Provided By University of Delaware

  • White Papers // Feb 2012

    Energy Efficiency of Distributed Cooperative Relaying

    Distributed cooperative relaying is an attractive method to combat fading in wireless communications because of its performance advantages, simplicity, scalability, and low overhead. In, the spectral efficiency of two previously pro-posed distributed relaying strategies is investigated: timer-based Best-Select relaying and M-group Dis-STBC All-Select relaying. From the perspective of spectral efficiency,...

    Provided By University of Delaware

  • White Papers // Feb 2012

    Energy-Efficient Best-Select Relaying in Wireless Cooperative Networks

    Due to the exponentially-increasing energy consumption of wireless mobile networks, energy efficiency has become an important metric in designing these networks. In this paper, the authors present an analysis of the energy efficiency of best-select relaying, where a single best relay is chosen to relay the source message, and compare...

    Provided By University of Delaware

  • White Papers // Jan 2012

    Energy Efficiency of Cooperative Beamforming in Wireless Ad-Hoc Networks

    Energy efficiency is a critical issue in wireless communication networks since most of the communication devices have limited energy capacity. Various strategies for maximizing energy efficiency have been proposed. In this paper, the authors analyze the energy efficiency of cooperative beamforming where the source and relay nodes construct a virtual...

    Provided By University of Delaware

  • White Papers // Jan 2012

    Towards an Integrated Multiscale Simulation of Turbulent Clouds on PetaScale Computers

    The development of precipitating warm clouds is affected by several effects of small-scale air turbulence including enhancement of droplet-droplet collision rate by turbulence, entrainment and mixing at the cloud edges, and coupling of mechanical and thermal energies at various scales. Large-scale computation is a viable research tool for quantifying these...

    Provided By University of Delaware

  • White Papers // Aug 2011

    Polytasks: A Compressed Task Representation for HPC Runtimes

    The increased number of execution units in many-core processors is driving numerous paradigm changes in parallel systems. Previous techniques that focused solely upon obtaining correct results are being rendered obsolete unless they can also provide results efficiently. This paper dives into the particular problem of efficiently supporting fine-grained task creation...

    Provided By University of Delaware

  • White Papers // Aug 2011

    TIDeFlow: The Time Iterated Dependency Flow Execution Model

    The many-core revolution brought forward by recent advances in computer architecture has created immense challenges in the writing of parallel programs for High Performance Computing (HPC). Development of parallel HPC programs remains an art, and a universal doctrine for synchronization, scheduling and execution in general has not been found for...

    Provided By University of Delaware

  • White Papers // Aug 2011

    Keynesian Fiscal Stimulus: What Have We Learned From The Great Recession?

    What have we learned from the Great Recession about Keynesian fiscal stimulus? This paper contains five sections that develop the following five points: there is confusion about what constitutes Keynesian fiscal stimulus; Economists are deeply divided about fiscal stimulus; A fundamental error has been committed by an influential economist in...

    Provided By University of Delaware

  • White Papers // Aug 2011

    OPELL and PM: A Case Study on Porting Shared Memory Programming Models to Accelerators Architectures

    Limits on applications and hardware technologies have put a stop to the frequency race during the 2000s. Designs now can be divided into homogeneous and heterogeneous ones. Homogeneous types are the easiest to use since most tool-chains and system software do not need too much of a rewrite. On the...

    Provided By University of Delaware

  • White Papers // Jul 2011

    Exploring Fine-Grained Task-Based Execution on Multi-GPU Systems

    Using multi-GPU systems, including GPU clusters, is gaining popularity in scientific computing. However, when using multiple GPUs concurrently, the conventional data parallel GPU programming paradigms, e.g., CUDA, cannot satisfactorily address certain issues, such as load balancing, GPU resource utilization, overlapping fine-grained computation with communication, etc. In this paper, the authors...

    Provided By University of Delaware

  • White Papers // Apr 2011

    Importance Filtering for Image Retargeting

    Content-aware image retargeting has attracted a lot of interests recently. The key and most challenging issue for this task is how to balance the tradeoff between preserving the important contents and minimizing the visual distortions on the consistency of the image structure. In this paper, the authors present a novel...

    Provided By University of Delaware

  • White Papers // Apr 2011

    Misbehaviors in TCP SACK Generation

    While analyzing CAIDA Internet traces of TCP traffic to detect instances of data reneging, the authors frequently observed seven misbehaviors in the generation of SACKs. These misbehaviors could result in a data sender mistakenly thinking data reneging occurred. With one misbehavior, the worst case could result in a data sender...

    Provided By University of Delaware

  • White Papers // Feb 2011

    Spectral Efficiency of Distributed Cooperative Relaying

    Cooperative relaying has been shown to be an effective method to combat fading in wireless communications. Among relaying strategies, distributed ones are more attractive because of the simplicity, scalability, robustness and low overhead incurred. In this paper, two previously proposed distributed relaying strategies are investigated: Timer-based Best-Select relaying and M-group...

    Provided By University of Delaware

  • White Papers // Feb 2011

    Robust Cooperative Relaying in an Amplify-and-Forward Network

    It has been shown that cooperative communication can significantly improve performance by utilizing distributed relay nodes. In most cases, cooperative communication systems have been designed and evaluated assuming perfect Channel State Information (CSI). Due to the feedback delay of the estimated CSI, a level of uncertainty in the channel estimates...

    Provided By University of Delaware

  • White Papers // Jan 2011

    Location-Aware Cooperative Routing in Multihop Wireless Networks

    Geographic routing is a scalable routing scheme for wireless networks, where nodes make local routing decisions using position information. Cooperative transmissions utilize spatial diversity to combat fading in wireless channels. In this paper, the authors incorporate cooperative transmissions into geographic routing, and propose the Location-Aware Cooperative Routing (LACR). In LACR,...

    Provided By University of Delaware

  • White Papers // Jan 2011

    CSR: Cooperative Source Routing Using Virtual MISO in Wireless Ad Hoc Networks

    Cooperative transmissions combat various fading effects in wireless communications by employing multiple antennas from different nodes to achieve spatial diversity. Virtual Multiple-Input Single-Output (MISO) is one instance of cooperative transmissions capable of achieving higher receiving SNR, which can either extend the transmission range or increase the transmission rate. While the...

    Provided By University of Delaware

  • White Papers // Jan 2011

    Scalability and Scheduling in an Agent Architecture

    For a given agent goal or objective there will be many different possible task execution paths for achieving the goal. One method for achieving the goal is to algorithmically determine the "Best" execution path execute that path. One question that arises with this strategy is what to do in the...

    Provided By University of Delaware

  • White Papers // Aug 2010

    Does Foreign Intellectual Property Rights Protection Affect U.S. Exports And FDI?

    Using GMM models on a panel data of fifty-three countries, the authors examine whether stronger foreign IPR protection stimulates international transactions of U.S. multinational firms. The empirical results suggest that foreign countries that strengthen their IPR protection, especially those with strong imitative ability, can attract more international transactions from U.S....

    Provided By University of Delaware

  • White Papers // May 2010

    Performance Analysis of Cooley-Tukey FFT Algorithms for a Many-Core Architecture

    Given that many-core architectures are becoming the mainstream framework for high performance computing, it is important to develop a performance model for many-core architectures to assist parallel algorithms design and applications performance tuning. In this paper, the authors propose a performance modeling technique for parallel Cooley-Tukey FFT algorithms, for an...

    Provided By University of Delaware

  • White Papers // Mar 2010

    Knowledge-capital, International Trade And Foreign Direct Investment: A Sectoral Analysis

    The Knowledge-Capital (KC) model of MNEs is now a widely adopted empirical approach to explaining the location and production decisions of global firms based on both horizontal and vertical motivations. While most of the existing studies have focused on highly aggregated national data, the authors extend this model to sectoral...

    Provided By University of Delaware

  • White Papers // Feb 2010

    Partitioned One-Bit Feedback for Cooperative Beamforming

    Recently, it has been shown that a cooperative beamforming scheme can achieve considerable gain using node cooperation. Due to the distributed nature of cooperating nodes, it is necessary to obtain phase synchronization such that the common message transmitted from the different cooperating nodes can be added coherently at the receiver....

    Provided By University of Delaware

  • White Papers // Feb 2010

    Organizational Power and Information Security Implementation

    This purpose of this paper is to show how the implementation of information systems security policies in an organization can be improved by applying a power exercise model. It argues that stakeholders' awareness of the power being exercised by the policy enforcers, affects the success of the policy implementation. The...

    Provided By University of Delaware

  • White Papers // Jan 2010

    Dynamic Load Balancing on Single-And Multi-GPU Systems

    The computational power provided by many-core Graphics Processing Units (GPUs) has been exploited in many applications. The programming techniques currently employed on these GPUs are not sufficient to address problems exhibiting irregular, and unbalanced workload. The problem is exacerbated when trying to effectively exploit multiple GPUs concurrently, which are commonly...

    Provided By University of Delaware

  • White Papers // Sep 2009

    Government Intervention To Prevent Bankruptcy: The Effect Of Blind-Bidding Laws On Movie Theaters

    In the 1970s motion picture studios used blind bidding and non-refundable guarantees to reduce the risks of producing large budget films. However, theater owners claimed that blind bidding and guarantees shifted the risk to them and increased the likelihood of bankruptcy. In response to lobbying by theater owners, twenty-four states...

    Provided By University of Delaware

  • White Papers // Aug 2009

    Lightweight Scheme for Generating Stealthy Probes

    Probing based approaches have been effectively used for network monitoring in the past. Probes such as ICMP pings provide an effective tool for detecting compromised nodes which try to delay or drop traffic. But an intelligent attacker may evade detection by giving preferential treatment to probe traffic. This is usually...

    Provided By University of Delaware

  • White Papers // Jul 2009

    The Complexity of RP Selection in Multicast Channelization

    Rendezvous Point (RP) selection for multicast groups is the problem of selecting a node to serve as the RP-host for a multicast group. The authors consider rendezvous point selection in the context of channelization where groups have been established based on user preferences for a set of available flows. Thus,...

    Provided By University of Delaware

  • White Papers // Jul 2009

    Improved Topology Control Algorithms for Simple Mobile Networks

    Topology control is the problem of assigning powers to the nodes of an ad hoc network so as to create a specified network topology while minimizing the energy consumed by the network nodes. Topology control in mobile wireless ad hoc networks under the Simple Mobile Network (SMN) Model was introduced....

    Provided By University of Delaware

  • White Papers // Jul 2009

    Financial Crisis, Monetary Policy Reform And The Monetary Transmission Mechanism In Turkey

    Turkey experienced a financial crisis in 2000-2001 which led to significant financial reforms. The reforms resulted in a switch to a floating exchange rate, granted greater central bank independence and pursuit of a more credible monetary policy. Investigation of the channels of monetary policy in both periods finds that monetary...

    Provided By University of Delaware

  • White Papers // Jun 2009

    Spreadsheet-Based Ultrasensitive Magnetic Field Sensor Design Tool Using Microsoft Excel

    A spreadsheet-based preliminary design and noise consideration system is presented in this paper. The system is developed using Microsoft Excel. It allows users to optimize the various parameters of magnetic field sensor designs with the goal of SQUID-like sensitivity. Users can input design parameters including materials, junction areas, and magnetic...

    Provided By University of Delaware

  • White Papers // Jun 2009

    PerfSONAR: Instantiating a Global Network Measurement Framework

    perfSONAR is a web services-based infrastructure for collecting and publishing network performance monitoring. A primary goal of perfSONAR is making it easier to solve end-to-end performance problems on paths crossing several networks. It contains a set of services delivering performance measurements in a federated environment. These services act as an...

    Provided By University of Delaware

  • White Papers // May 2009

    Tile Percolation: An OpenMP Tile Aware Parallelization Technique for the Cyclops-64 Multicore Processor

    Programming a multicore processor is difficult. It is even more difficult if the processor has software-managed memory hierarchy, e.g. the IBM Cyclops-64 (C64). A widely accepted parallel programming solution for multicore processor is OpenMP. Currently, all OpenMP directives are only used to decompose computation code (such as loop iterations, tasks,...

    Provided By University of Delaware

  • White Papers // Mar 2009

    Practical Computation of Optimal Schedules in Multihop Wireless Networks

    Interference and collisions greatly limit the throughput of mesh networks that use contention-based MAC protocols such as 802.11. Significantly higher throughput is achievable if transmissions are scheduled. However, traditional methods to compute optimal schedules are computationally intractable (unless co-channel interference is neglected). This paper presents a practical technique to compute...

    Provided By University of Delaware

  • White Papers // Mar 2009

    The Impact of Channel Usage Information on the Throughput Achieved by 802.11-Style MACs in Urban Mesh Networks

    It is well known that in dense mesh networks, CSMA-based MACs such as IEEE 802.11 achieve lower throughput than optimal spatial TDMA. This paper explores the degree to which the difference in throughput is partly due to a lack of channel usage information and the degree to which the difference...

    Provided By University of Delaware

  • White Papers // Feb 2009

    Automatically Capturing Source Code Context of NL-Queries for Software Maintenance and Reuse

    As software systems continue to grow and evolve, locating code for maintenance and reuse tasks becomes increasingly difficult. Existing static code search techniques using natural language queries provide little support to help developers determine whether search results are relevant, and few recommend alternative words to help developers reformulate poor queries....

    Provided By University of Delaware

  • White Papers // Sep 2012

    E-Governance: Past, Present and Future in India

    Online working of a government or providing its services online to its citizens at their door step is known as E-Governance. E-Governance is E-Commerce technology means online availability of government services. The technology and the methods used in E-Governance project provide a roadmap for efficient delivery of services at the...

    Provided By University of Delaware

  • White Papers // Jun 2012

    Optimal Component Selection Problem for Cots Based Software System Under Consensus Recovery Block Scheme: A Goal Programming Approach

    Cost, reliability and time are the three main quality attributes of a software system. Now days much software are designed on COTS component in order to facilitate timely development with reduced cost and improved reliability. Software designed to handle critical control systems have very high reliability requirements. Fault tolerance is...

    Provided By University of Delaware

  • White Papers // Mar 2013

    Modeling the Navigation Behavior of Dynamic Web Applications

    In order to manage the growing complexity of web applications, there is a need to abstract and model different system behaviors which simplify the process of analysis, designing, verification, testing and maintenance to improve the quality and reliability of web applications. Navigation of a web application is the sequence of...

    Provided By University of Delaware

  • White Papers // Feb 2013

    Energy-Based Performance Evaluation of Various Routing Protocols in Infrastructure-Less Opportunistic Networks

    Opportunistic networks (Oppnets) provide the communication facilities in the network scenarios where the end-to-end path between the source and the destination never exists or may last only for an unpredictable and very short period of time. The disconnections and re-connections between the nodes are very common in Oppnets. In this...

    Provided By University of Delaware

  • White Papers // Feb 2010

    Organizational Power and Information Security Implementation

    This purpose of this paper is to show how the implementation of information systems security policies in an organization can be improved by applying a power exercise model. It argues that stakeholders' awareness of the power being exercised by the policy enforcers, affects the success of the policy implementation. The...

    Provided By University of Delaware

  • White Papers // Jun 2009

    Spreadsheet-Based Ultrasensitive Magnetic Field Sensor Design Tool Using Microsoft Excel

    A spreadsheet-based preliminary design and noise consideration system is presented in this paper. The system is developed using Microsoft Excel. It allows users to optimize the various parameters of magnetic field sensor designs with the goal of SQUID-like sensitivity. Users can input design parameters including materials, junction areas, and magnetic...

    Provided By University of Delaware

  • White Papers // Oct 2007

    Do Firms Adjust To A Target Board Structure?

    The authors propose that firms have economically efficient and optimal board structures which they adjust to over time. Using a partial adjustment model and a broad panel of board structure changes over the period from 1991 - 2003, they find evidence in support of this hypothesis. Over any two year...

    Provided By University of Delaware

  • White Papers // Sep 2008

    Multiple TCP Connections Improve HTTP Throughput ? Myth or Fact?

    The earlier research showed that HTTP over TCP suffers from aggravated Head-Of-Line (HOL) blocking in browsing conditions found in the developing world. The paper proposed a multistreamed transport such as SCTP to alleviate HOL blocking. Using emulations the paper showed that a single multistreamed SCTP association reduced HOL blocking and...

    Provided By University of Delaware

  • White Papers // Apr 2011

    Importance Filtering for Image Retargeting

    Content-aware image retargeting has attracted a lot of interests recently. The key and most challenging issue for this task is how to balance the tradeoff between preserving the important contents and minimizing the visual distortions on the consistency of the image structure. In this paper, the authors present a novel...

    Provided By University of Delaware

  • White Papers // Jan 2011

    Scalability and Scheduling in an Agent Architecture

    For a given agent goal or objective there will be many different possible task execution paths for achieving the goal. One method for achieving the goal is to algorithmically determine the "Best" execution path execute that path. One question that arises with this strategy is what to do in the...

    Provided By University of Delaware

  • White Papers // Feb 2009

    Automatically Capturing Source Code Context of NL-Queries for Software Maintenance and Reuse

    As software systems continue to grow and evolve, locating code for maintenance and reuse tasks becomes increasingly difficult. Existing static code search techniques using natural language queries provide little support to help developers determine whether search results are relevant, and few recommend alternative words to help developers reformulate poor queries....

    Provided By University of Delaware

  • White Papers // Mar 2010

    Knowledge-capital, International Trade And Foreign Direct Investment: A Sectoral Analysis

    The Knowledge-Capital (KC) model of MNEs is now a widely adopted empirical approach to explaining the location and production decisions of global firms based on both horizontal and vertical motivations. While most of the existing studies have focused on highly aggregated national data, the authors extend this model to sectoral...

    Provided By University of Delaware

  • White Papers // Apr 2011

    Misbehaviors in TCP SACK Generation

    While analyzing CAIDA Internet traces of TCP traffic to detect instances of data reneging, the authors frequently observed seven misbehaviors in the generation of SACKs. These misbehaviors could result in a data sender mistakenly thinking data reneging occurred. With one misbehavior, the worst case could result in a data sender...

    Provided By University of Delaware

  • White Papers // Aug 2010

    Does Foreign Intellectual Property Rights Protection Affect U.S. Exports And FDI?

    Using GMM models on a panel data of fifty-three countries, the authors examine whether stronger foreign IPR protection stimulates international transactions of U.S. multinational firms. The empirical results suggest that foreign countries that strengthen their IPR protection, especially those with strong imitative ability, can attract more international transactions from U.S....

    Provided By University of Delaware

  • White Papers // Feb 2009

    Networking With Cooperative Communications: Holistic Design and Realistic Evaluation

    Cooperative communications fundamentally changes the abstraction of a wireless link and offers significant potential advantages for wireless networks. However, much of the existing work on cooperative systems focuses on their physical layer capabilities. Such systems are evaluated with idealized scenarios where coordination, control signaling, and other costs are assumed to...

    Provided By University of Delaware

  • White Papers // Sep 2009

    Government Intervention To Prevent Bankruptcy: The Effect Of Blind-Bidding Laws On Movie Theaters

    In the 1970s motion picture studios used blind bidding and non-refundable guarantees to reduce the risks of producing large budget films. However, theater owners claimed that blind bidding and guarantees shifted the risk to them and increased the likelihood of bankruptcy. In response to lobbying by theater owners, twenty-four states...

    Provided By University of Delaware

  • White Papers // Aug 2011

    Keynesian Fiscal Stimulus: What Have We Learned From The Great Recession?

    What have we learned from the Great Recession about Keynesian fiscal stimulus? This paper contains five sections that develop the following five points: there is confusion about what constitutes Keynesian fiscal stimulus; Economists are deeply divided about fiscal stimulus; A fundamental error has been committed by an influential economist in...

    Provided By University of Delaware

  • White Papers // Jul 2009

    Financial Crisis, Monetary Policy Reform And The Monetary Transmission Mechanism In Turkey

    Turkey experienced a financial crisis in 2000-2001 which led to significant financial reforms. The reforms resulted in a switch to a floating exchange rate, granted greater central bank independence and pursuit of a more credible monetary policy. Investigation of the channels of monetary policy in both periods finds that monetary...

    Provided By University of Delaware

  • White Papers // Jan 2011

    CSR: Cooperative Source Routing Using Virtual MISO in Wireless Ad Hoc Networks

    Cooperative transmissions combat various fading effects in wireless communications by employing multiple antennas from different nodes to achieve spatial diversity. Virtual Multiple-Input Single-Output (MISO) is one instance of cooperative transmissions capable of achieving higher receiving SNR, which can either extend the transmission range or increase the transmission rate. While the...

    Provided By University of Delaware

  • White Papers // Aug 2009

    Lightweight Scheme for Generating Stealthy Probes

    Probing based approaches have been effectively used for network monitoring in the past. Probes such as ICMP pings provide an effective tool for detecting compromised nodes which try to delay or drop traffic. But an intelligent attacker may evade detection by giving preferential treatment to probe traffic. This is usually...

    Provided By University of Delaware

  • White Papers // Feb 2011

    Spectral Efficiency of Distributed Cooperative Relaying

    Cooperative relaying has been shown to be an effective method to combat fading in wireless communications. Among relaying strategies, distributed ones are more attractive because of the simplicity, scalability, robustness and low overhead incurred. In this paper, two previously proposed distributed relaying strategies are investigated: Timer-based Best-Select relaying and M-group...

    Provided By University of Delaware

  • White Papers // Feb 2009

    Using Temporal Correlation for Fault Localization in Dynamically Changing Networks

    A mobile ad-hoc network creates a dynamic environment where node mobility can cause periodic changes in routes. Most existing fault localization algorithms assume availability of complete and/or deterministic dependency model. Such assumptions can not be made in the dynamically changing networks. This paper is aimed at developing a fault diagnosis...

    Provided By University of Delaware

  • White Papers // Jan 2011

    Location-Aware Cooperative Routing in Multihop Wireless Networks

    Geographic routing is a scalable routing scheme for wireless networks, where nodes make local routing decisions using position information. Cooperative transmissions utilize spatial diversity to combat fading in wireless channels. In this paper, the authors incorporate cooperative transmissions into geographic routing, and propose the Location-Aware Cooperative Routing (LACR). In LACR,...

    Provided By University of Delaware

  • White Papers // Mar 2009

    The Impact of Channel Usage Information on the Throughput Achieved by 802.11-Style MACs in Urban Mesh Networks

    It is well known that in dense mesh networks, CSMA-based MACs such as IEEE 802.11 achieve lower throughput than optimal spatial TDMA. This paper explores the degree to which the difference in throughput is partly due to a lack of channel usage information and the degree to which the difference...

    Provided By University of Delaware

  • White Papers // Jul 2009

    Improved Topology Control Algorithms for Simple Mobile Networks

    Topology control is the problem of assigning powers to the nodes of an ad hoc network so as to create a specified network topology while minimizing the energy consumed by the network nodes. Topology control in mobile wireless ad hoc networks under the Simple Mobile Network (SMN) Model was introduced....

    Provided By University of Delaware

  • White Papers // Jul 2009

    The Complexity of RP Selection in Multicast Channelization

    Rendezvous Point (RP) selection for multicast groups is the problem of selecting a node to serve as the RP-host for a multicast group. The authors consider rendezvous point selection in the context of channelization where groups have been established based on user preferences for a set of available flows. Thus,...

    Provided By University of Delaware

  • White Papers // Mar 2009

    Practical Computation of Optimal Schedules in Multihop Wireless Networks

    Interference and collisions greatly limit the throughput of mesh networks that use contention-based MAC protocols such as 802.11. Significantly higher throughput is achievable if transmissions are scheduled. However, traditional methods to compute optimal schedules are computationally intractable (unless co-channel interference is neglected). This paper presents a practical technique to compute...

    Provided By University of Delaware

  • White Papers // Aug 2011

    TIDeFlow: The Time Iterated Dependency Flow Execution Model

    The many-core revolution brought forward by recent advances in computer architecture has created immense challenges in the writing of parallel programs for High Performance Computing (HPC). Development of parallel HPC programs remains an art, and a universal doctrine for synchronization, scheduling and execution in general has not been found for...

    Provided By University of Delaware

  • White Papers // Jul 2011

    Exploring Fine-Grained Task-Based Execution on Multi-GPU Systems

    Using multi-GPU systems, including GPU clusters, is gaining popularity in scientific computing. However, when using multiple GPUs concurrently, the conventional data parallel GPU programming paradigms, e.g., CUDA, cannot satisfactorily address certain issues, such as load balancing, GPU resource utilization, overlapping fine-grained computation with communication, etc. In this paper, the authors...

    Provided By University of Delaware

  • White Papers // Jan 2012

    Towards an Integrated Multiscale Simulation of Turbulent Clouds on PetaScale Computers

    The development of precipitating warm clouds is affected by several effects of small-scale air turbulence including enhancement of droplet-droplet collision rate by turbulence, entrainment and mixing at the cloud edges, and coupling of mechanical and thermal energies at various scales. Large-scale computation is a viable research tool for quantifying these...

    Provided By University of Delaware

  • White Papers // Aug 2011

    Polytasks: A Compressed Task Representation for HPC Runtimes

    The increased number of execution units in many-core processors is driving numerous paradigm changes in parallel systems. Previous techniques that focused solely upon obtaining correct results are being rendered obsolete unless they can also provide results efficiently. This paper dives into the particular problem of efficiently supporting fine-grained task creation...

    Provided By University of Delaware

  • White Papers // Aug 2011

    OPELL and PM: A Case Study on Porting Shared Memory Programming Models to Accelerators Architectures

    Limits on applications and hardware technologies have put a stop to the frequency race during the 2000s. Designs now can be divided into homogeneous and heterogeneous ones. Homogeneous types are the easiest to use since most tool-chains and system software do not need too much of a rewrite. On the...

    Provided By University of Delaware

  • White Papers // May 2009

    Tile Percolation: An OpenMP Tile Aware Parallelization Technique for the Cyclops-64 Multicore Processor

    Programming a multicore processor is difficult. It is even more difficult if the processor has software-managed memory hierarchy, e.g. the IBM Cyclops-64 (C64). A widely accepted parallel programming solution for multicore processor is OpenMP. Currently, all OpenMP directives are only used to decompose computation code (such as loop iterations, tasks,...

    Provided By University of Delaware

  • White Papers // May 2012

    Traffic Optimization Through Information Dissemination

    It is a known fact today that VANETs are going to play an increasingly important role in vehicular communication in the future. The impact of these networks especially to solve the problem of traffic optimization and control is significant. Traffic Optimization through Information Dissemination (TOID) is an algorithm based on...

    Provided By University of Delaware

  • White Papers // Jan 2010

    Dynamic Load Balancing on Single-And Multi-GPU Systems

    The computational power provided by many-core Graphics Processing Units (GPUs) has been exploited in many applications. The programming techniques currently employed on these GPUs are not sufficient to address problems exhibiting irregular, and unbalanced workload. The problem is exacerbated when trying to effectively exploit multiple GPUs concurrently, which are commonly...

    Provided By University of Delaware

  • White Papers // May 2010

    Performance Analysis of Cooley-Tukey FFT Algorithms for a Many-Core Architecture

    Given that many-core architectures are becoming the mainstream framework for high performance computing, it is important to develop a performance model for many-core architectures to assist parallel algorithms design and applications performance tuning. In this paper, the authors propose a performance modeling technique for parallel Cooley-Tukey FFT algorithms, for an...

    Provided By University of Delaware

  • White Papers // Feb 2012

    Maximal Throughput Routing in Wireless Linear Networks

    To design an efficient wireless routing scheme, both the physical characteristics of wireless links and the related networking activities must be taken into account. Simply applying the routing algorithms used in wired networks has been shown to be a suboptimal approach because of the fundamental differences between wireless and wired...

    Provided By University of Delaware

  • White Papers // Feb 2012

    Spectral Efficiency of Cooperative Relaying With Imperfect Channel Estimation

    It is well known that cooperative relaying has the potential to improve the performance of end-to-end wireless communications. However, compared to point-to-point communications, implementing cooperative relaying requires much more overhead. For example, more complicated coordination and transmission schemes are required. In this paper, the spectral efficiency of cooperative relaying is...

    Provided By University of Delaware

  • White Papers // Feb 2012

    Energy Efficiency of Distributed Cooperative Relaying

    Distributed cooperative relaying is an attractive method to combat fading in wireless communications because of its performance advantages, simplicity, scalability, and low overhead. In, the spectral efficiency of two previously pro-posed distributed relaying strategies is investigated: timer-based Best-Select relaying and M-group Dis-STBC All-Select relaying. From the perspective of spectral efficiency,...

    Provided By University of Delaware

  • White Papers // Jun 2009

    PerfSONAR: Instantiating a Global Network Measurement Framework

    perfSONAR is a web services-based infrastructure for collecting and publishing network performance monitoring. A primary goal of perfSONAR is making it easier to solve end-to-end performance problems on paths crossing several networks. It contains a set of services delivering performance measurements in a federated environment. These services act as an...

    Provided By University of Delaware