University of Virginia

Displaying 1-40 of 96 results

  • White Papers // Feb 2014

    Extra Bits on SRAM and DRAM Errors - More Data from the Field

    Several recent publications have shown that memory errors are common in high-performance computing systems, due to hardware faults in the memory subsystem. With exascale-class systems predicted to have 100-350x more DRAM and SRAM than current systems, these faults are predicted to become more common. Therefore, further study of the faults...

    Provided By University of Virginia

  • White Papers // Jul 2013

    PCF: A Portable Circuit Format for Scalable Two-Party Secure Computation

    A secure computation protocol for a function f (x; y) must leak no information about inputs x; y during its execution; thus it is imperative to compute the function f in a data-oblivious manner. Traditionally, this has been accomplished by compiling f into a Boolean circuit. Previous approaches, however, have...

    Provided By University of Virginia

  • White Papers // May 2012

    A Model and Decision Procedure for Data Storage in Cloud Computing

    Cloud computing offers many possibilities for prospective users; there are however many different storage and compute services to choose from between all the cloud providers and their multiple datacenters. In this paper, the authors focus on the problem of selecting the best storage services according to the application's requirements and...

    Provided By University of Virginia

  • White Papers // Mar 2012

    A Systematic Study of Automated Program Repair: Fixing 55 Out of 105 Bugs for $8 Each

    There are more bugs in real-world programs than human programmers can realistically address. This paper evaluates two research questions: "What fraction of bugs can be repaired automatically?" and "How much does it cost to repair a bug automatically?" In previous work, the authors presented GenProg, which uses genetic programming to...

    Provided By University of Virginia

  • White Papers // Mar 2012

    Synthesizing API Usage Examples

    Key program interfaces are sometimes documented with usage examples: concrete code snippets that characterize common use cases for a particular data type. While such documentation is known to be of great utility, it is burdensome to create and can be incomplete, out of date, or not representative of actual practice....

    Provided By University of Virginia

  • White Papers // Dec 2011

    Relationship Between Career Program Characteristics and Job Satisfaction in a City Based Local Authority

    According to the human resource development literature, career program has two salient characteristics: career planning and career management. Recent studies in this area reveal that the ability of management to properly implement such career program characteristics may have a significant impact on job satisfaction. Although the nature of this relationship...

    Provided By University of Virginia

  • White Papers // Dec 2011

    Assessing the Value of Cloudbursting: A Case Study of Satellite Image Processing on Windows Azure

    To perform computational experiments at greater scale and in less time, enterprises are increasingly looking to dynamically expand their computing capabilities through the temporary addition of cloud resources (aka "Cloud-bursting"). Computational infrastructure can be dismantled in minutes with no long-term capital investments. However, research is needed to identify which properties...

    Provided By University of Virginia

  • White Papers // Jun 2011

    GuardRails: A Data-Centric Web Application Security Framework

    Modern web application frameworks have made it easy to create powerful web applications. Developing a secure web application, however, still requires a developer to posses a deep understanding of security vulnerabilities and attacks. Even for experienced developers it is tedious, if not impossible, to find and eliminate all vulnerabilities. This...

    Provided By University of Virginia

  • White Papers // Jun 2011

    Kicking The Dog: Korea's Bureaucratic Resistance To Globalization In Reaction To Democratization

    Seven years have passed since the Korean economy was engulfed by the 1997 Asian Financial Crisis. Arguably, the country is still not fully recovered from the catastrophe almost a decade later. In those intervening years, numerous books and papers have attempted to diagnose the origins of the extraordinarily sharp downturn...

    Provided By University of Virginia

  • White Papers // May 2011

    Private Editing Using Untrusted Cloud Services

    The authors present a general methodology for protecting the confidentiality and integrity of user data for a class of on-line editing applications. The key insight is that many of these applications are designed to perform most of their data-dependent computation on the client side, so it is possible to maintain...

    Provided By University of Virginia

  • White Papers // Apr 2011

    Feasibility of Dynamic Binary Parallelization

    This paper proposes DBP, an automatic technique that transparently parallelizes a sequential binary executable while it is running. A prototype implementation in simulation was able to increase sequential execution speeds by up to 1.96x, averaged over three benchmarks suites. Fundamental issues in microprocessor technologies have led designers to increase the...

    Provided By University of Virginia

  • White Papers // Apr 2011

    Interest Rates And Inflation

    For some time now the author have been intrigued by the apparent relationship between the behavior of various interest rates and that of inflation. As a physicist, the author views economics the same way the author views physical systems. Namely, describe them by a model which is amenable to mathematical...

    Provided By University of Virginia

  • White Papers // Mar 2011

    An Analysis of Using High-Frequency Sinusoidal Illumination to Measure the 3D Shape of Translucent Objects

    Using optical triangulation methods to measure the shape of translucent objects is difficult because subsurface scattering contaminates measurements of the "Direct" reflection at the surface. A number of recent papers have shown that high-frequency sinusoidal illumination patterns allow isolating this direct component, which in turn enables accurate estimation of the...

    Provided By University of Virginia

  • White Papers // Mar 2011

    Analytic Error Modeling for Imprecise Arithmetic Circuits

    Imprecise hardware challenges the traditional notion that correctness is an immutable priority, by systematically trading off efficacy (precision) against efficiency (power, area, performance, and cost). Evaluating the impact of such tradeoffs on output quality using, e.g., Monte Carlo simulations is a time-consuming and non-deterministic process. This paper presents two analytic...

    Provided By University of Virginia

  • White Papers // Mar 2011

    Extending SAT Solvers to Cryptographic Problems

    Cryptography ensures the con confidentiality and authenticity of information but often relies on unproven assumptions. SAT solvers are a powerful tool to test the hardness of certain problems and have successfully been used to test hardness assumptions. This paper extends a SAT solver to efficiently work on cryptographic problems. The...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Where Is the Data? Why You Cannot Debate CPU Vs. GPU Performance Without the Answer

    General Purpose GPU Computing (GPGPU) has taken off in the past few years, with great promises for increased desktop processing power due to the large number of fast computing cores on high-end graphics cards. Many publications have demonstrated phenomenal performance and have reported speedups as much as 1000x over code...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Improving Region Selection Through Loop Completion

    Dynamic binary translation is a powerful technique for program analysis and modification that operates on binary code as it executes, thus availing itself of information only available at run-time. However, by intervening between the software and hardware, a significant slowdown may be introduced into program execution, which can hinder widespread...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Improving Indirect Branch Translation in Dynamic Binary Translators

    Dynamic Binary Translators (DBTs) have a wide range of applications including program instrumentation, dynamic optimization, and security. One of the main issues with DBTs is their performance overhead. A significant part of this overhead is caused by Indirect Branch (IB) translation. In this paper, the authors show that the percentage...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Distributed Uplink Resource Allocation in Cognitive Radio Networks - Part II: Equilibria and Algorithms for Joint Access Point Selection and Power Allocation

    The main objective of this two part paper is to formulate and address the problem of distributed uplink resource allocation in multi-carrier Cognitive Radio Networks (CRN) with multiple Access Points (APs). When the APs operate on non-overlapping spectrum bands, such problem is essentially a joint spectrum decision and spectrum sharing...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Joint Distributed Access Point Selection and Power Allocation in Cognitive Radio Networks

    Spectrum management has been identified as a crucial step towards enabling the technology of the Cognitive Radio Network (CRN). Most of the current works dealing with spectrum management in the CRN focus on a single task of the problem, e.g., spectrum sensing, spectrum decision, spectrum sharing or spectrum mobility. In...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Efficient Privacy-Preserving Biometric Identification

    The authors present an efficient matching protocol that can be used in many privacy-preserving biometric identification systems in the semi-honest setting. The most general technical contribution is a new backtracking protocol that uses the byproduct of evaluating a garbled circuit to enable efficient oblivious information retrieval. They also present a...

    Provided By University of Virginia

  • White Papers // Feb 2011

    A Sub-0.5V Lattice-Based Public-Key Encryption Scheme for RFID Platforms in 130nm CMOS

    Implementing public-key cryptography on passive RFID tags is very challenging due to the limited die size and power available. Typical public-key algorithms require complex logical components such as modular exponentiation in RSA. The authors demonstrate the feasibility of implementing public-key encryption on low-power, low cost passive RFID tags to large-scale...

    Provided By University of Virginia

  • White Papers // Jan 2011

    Bandwidth Allocation in Hexagonal Wireless Sensor Networks for Real-Time Communications

    This paper presents an algorithm for bandwidth allocation for delay-sensitive traffic in multi-hop wireless sensor networks. The solution considers both periodic as well as a periodic real-time traffic in an unified manner. The authors also present a distributed MAC protocol that conforms to the bandwidth allocation and thus satisfies the...

    Provided By University of Virginia

  • White Papers // Jan 2011

    Enviro-Track: Towards an Environmental Computing Paradigm for Distributed Sensor Networks

    Distributed sensor networks are quickly gaining recognition as viable embedded computing platforms. Current techniques for programming sensor networks are cumbersome, inflexible, and low-level. This paper introduces EnviroTrack, an object-based distributed middleware system that raises the level of programming abstraction by providing a convenient and powerful interface to the application developer...

    Provided By University of Virginia

  • White Papers // Jan 2011

    Thunder: Towards Practical, Zero Cost Acoustic Localization for Outdoor Wireless Sensor Networks

    Localization for outdoor wireless sensor networks has been a challenge for real applications. Although many solutions have been proposed, few of them can be used in real applications because of their high cost, low accuracy or infeasibility due to practical issues. In this paper, the authors propose a practical acoustic...

    Provided By University of Virginia

  • White Papers // Jan 2011

    A Performance Study of General Purpose Applications on Graphics Processors

    Graphic Processors Unit (GPUs), with many light-weight data-parallel cores, can provide substantial parallel computational power to accelerate general purpose applications. To best utilize the GPU's parallel computing resources, it is crucial to understand how GPU architectures and programming models can be applied to different categories of traditionally CPU applications. In...

    Provided By University of Virginia

  • White Papers // Jan 2011

    Accelerating Compute-Intensive Applications With GPUs and FPGAs

    Accelerators are special purpose processors designed to speed up compute-intensive sections of applications. Two extreme endpoints in the spectrum of possible accelerators are FPGAs and GPUs, which can often achieve better performance than CPUs on certain workloads. FPGAs are highly customizable, while GPUs provide massive parallel execution resources and high...

    Provided By University of Virginia

  • White Papers // Jan 2011

    CMP Design Space Exploration Subject to Physical Constraints

    This paper explores the multi-dimensional design space for chip multiprocessors, exploring the inter-related variables of core count, pipeline depth, superscalar width, L2 cache size, and operating voltage and frequency, under various area and thermal constraints. The results show the importance of joint optimization. Thermal constraints dominate other physical constraints such...

    Provided By University of Virginia

  • White Papers // Jan 2011

    An Entity Maintenance and Connection Service for Sensor Networks

    In this paper, the authors present a middleware architecture for coordination services in sensor networks that facilitates interaction between groups of sensors which monitor different environmental events. It sits on top of the native routing infrastructure and exports the abstraction of mobile communication endpoints maintained at the locations of such...

    Provided By University of Virginia

  • White Papers // Jan 2011

    A Communication Architecture and Programming Abstractions for Real-Time Embedded Sensor Networks

    Data distribution in embedded real-time sensor networks requires new protocols and programming environments that achieve time-sensitive message delivery and provide useful abstractions to the application programmer. Attainment of these goals requires changes to multiple layers of the communication protocol stack. In this paper, the authors review a protocol suite developed...

    Provided By University of Virginia

  • White Papers // Jan 2011

    Heterogeneous Chip Multiprocessor Design for Virtual Machines

    Multi-core architectures provide an alternative to increasing clock frequencies to improve performance of modern processors. The best design for these chip multiprocessors, including structure sizes or whether to use homogeneous or heterogeneous cores, remains open for exploration. One potential design path involves using heterogeneous cores that are specialized for a...

    Provided By University of Virginia

  • White Papers // Dec 2010

    Modeling and Analyzing NBTI in the Presence of Process Variation

    With continuous scaling of transistors in each technology generation, NBTI and Process Variation (PV) have become very important silicon reliability problems for the microprocessor industry. In this paper, the authors develop an analytical model to capture the impact of NBTI in the presence of PV for use in architecture simulations....

    Provided By University of Virginia

  • White Papers // Dec 2010

    Looking For Local Labor-Market Effects Of The NAFTA

    Using US Census data for 1990 and 2000, the authors estimate effects of the NAFTA agreement on the US wages. They look for any indication of effects of the agreement on local labor markets dependent on industries vulnerable to import competition from Mexico, and workers employed in industries competing with...

    Provided By University of Virginia

  • White Papers // Dec 2010

    Looking For Local-Labor-Market Effects Of NAFTA

    Using US Census data for 1990 and 2000, the authors estimate effects of the NAFTA agreement on the US wages. They look for any indication of effects of the agreement on the local labor markets dependent on industries vulnerable to import competition from Mexico, and the workers employed in industries...

    Provided By University of Virginia

  • White Papers // Dec 2010

    Applicability of the Willow Architecture for Cloud Management

    The differences between grids and clouds arguably include objectives, organization, scale, and workload. By examining these fundamental characteristics and requirements in detail, the authors assess the degree to which a generic management infrastructure for grid computing can be applied to cloud infrastructures. The analysis is further refined by considering a...

    Provided By University of Virginia

  • White Papers // Dec 2010

    Relaxing Non-Volatility for Fast and Energy-Efficient STT-RAM Caches

    Spin-Transfer Torque RAM (STT-RAM) is an emerging non-volatile memory technology that is a potential universal memory that could replace SRAM in processor caches. This paper presents a novel approach for redesigning STT-RAM memory cells to reduce the high dynamic energy and slow write latencies. The authors lower the retention time...

    Provided By University of Virginia

  • White Papers // Dec 2010

    Fault Tolerance and Scaling in e-Science Cloud Applications: Observations From the Continuing Development of MODISAzure

    It can be natural to believe that many of the traditional issues of scale have been eliminated or at least greatly reduced via cloud computing. That is, if one can create a seemingly well-functioning cloud application that operates correctly on small or moderate-sized problems, then the very nature of cloud...

    Provided By University of Virginia

  • White Papers // Dec 2010

    CSAL: A Cloud Storage Abstraction Layer to Enable Portable Cloud Applications (work-in-Progress)

    One of the large impediments for adoption of cloud computing is perceived vendor lock-in with respect to both low-level resource management and application level storage services. Application portability is essential to both avoid lock-in as well as leverage the ever changing landscape of cloud offerings. The authors present a storage...

    Provided By University of Virginia

  • White Papers // Dec 2010

    Shouting To Be Heard In Advertising

    Advertising competes for consumer attention, but attention is scarce. More profitable senders send more messages to break through the clutter. There may be multiple equilibria: more messages in aggregate induce more "Shouting to be heard" among senders trying to break through the advertising clutter, which creates a "Lottery ticket" dimension...

    Provided By University of Virginia

  • White Papers // Oct 2010

    A Human Study of Fault Localization Accuracy

    Localizing and repairing defects are critical software engineering activities. Not all programs and not all bugs are equally easy to debug, however. They present formal models, backed by a human study involving 65 participants (from both academia and industry) and 1830 total judgments, relating various software- and defect-related features to...

    Provided By University of Virginia

  • White Papers // Feb 2010

    Using Height Sensors for Biometric Identification in Multi-Resident Homes

    In this paper the authors evaluate the use of height for biometric identification of residents, by mounting ultrasonic distance sensors above the doorways in a home. Height sensors are cheap, are convenient for the residents, are simple to install in an existing home, and are perceived to be less invasive...

    Provided By University of Virginia

  • White Papers // May 2010

    QueueTrak: Automated Line Length Detection Using a Wireless Sensor Network

    This paper describes QueueTrak, an automated wireless sensor system designed to detect and report the length of lines in retail environments. QueueTrak has two components. First, it uses a series of custom active infrared sensors to detect the length of a line in a store or restaurant. Second, a web...

    Provided By University of Virginia

  • White Papers // Apr 2010

    Melange: Supporting Heterogeneous QoS Requirements in Delay Tolerant Sensor Networks

    In sparse mobile sensor networks, nodes have a small number of neighbors with intermittent connectivity. This paper presents a new networking protocol for this type of network, aimed at maximizing system performance in terms of both delay and reliability. The system is motivated by the observation that many applications on...

    Provided By University of Virginia

  • White Papers // Dec 2009

    IAA: Interference Aware Anticipatory Algorithm for Scheduling and Routing Periodic Real-Time Streams in Wireless Sensor Networks

    This paper provides a polynomial time heuristic for the real-time communication scheduling problem in multi-hop wireless sensor networks. Wireless networks add a new dimension to the real-time communication problem because of interference: a transmission cannot be scheduled on a radio link if another transmission is scheduled on any interfering link....

    Provided By University of Virginia

  • White Papers // Dec 2010

    CSAL: A Cloud Storage Abstraction Layer to Enable Portable Cloud Applications (work-in-Progress)

    One of the large impediments for adoption of cloud computing is perceived vendor lock-in with respect to both low-level resource management and application level storage services. Application portability is essential to both avoid lock-in as well as leverage the ever changing landscape of cloud offerings. The authors present a storage...

    Provided By University of Virginia

  • White Papers // Apr 2010

    EScience in the Cloud: A MODIS Satellite Data Reprojection and Reduction Pipeline in the Windows Azure Platform

    The combination of low-cost sensors, low-cost commodity computing, and the Internet is enabling a new era of data-intensive science. The dramatic increase in this data availability has created a new challenge for scientists: how to process the data. Scientists today are envisioning scientific computations on large scale data but are...

    Provided By University of Virginia

  • White Papers // Mar 2010

    Automatically Exporting TinyOS Modules as Web Services

    As embedded devices become increasingly useful and ubiquitous, it will be important to incorporate them into enterprise applications through Web services and service-oriented architectures. Existing approaches have limitations in terms of either resource consumption or burden on the programmer. This paper presents a new framework to automatically export TinyOS modules...

    Provided By University of Virginia

  • White Papers // Aug 2010

    U.S. International Equity Investment

    U.S. investors are the largest group of international equity investors in the world, but to date conclusive evidence on which types of foreign firms are able to attract U.S. investment is not available. Authors use a comprehensive dataset of all U.S. investment in all foreign equities to address this issue....

    Provided By University of Virginia

  • White Papers // Dec 2010

    Looking For Local-Labor-Market Effects Of NAFTA

    Using US Census data for 1990 and 2000, the authors estimate effects of the NAFTA agreement on the US wages. They look for any indication of effects of the agreement on the local labor markets dependent on industries vulnerable to import competition from Mexico, and the workers employed in industries...

    Provided By University of Virginia

  • White Papers // Jan 2011

    Thunder: Towards Practical, Zero Cost Acoustic Localization for Outdoor Wireless Sensor Networks

    Localization for outdoor wireless sensor networks has been a challenge for real applications. Although many solutions have been proposed, few of them can be used in real applications because of their high cost, low accuracy or infeasibility due to practical issues. In this paper, the authors propose a practical acoustic...

    Provided By University of Virginia

  • White Papers // Sep 2009

    Towards Stable Network Performance in Wireless Sensor Networks

    Many applications in wireless sensor networks require communication performance that is both consistent and high quality. Unfortunately, performance of current network protocols can vary significantly because of various interferences and environmental changes. Current protocols estimate link quality based on the reception of probe packets over a short time period is...

    Provided By University of Virginia

  • White Papers // Apr 2010

    Recovery Boosting: A Technique to Enhance NBTI Recovery in SRAM Arrays

    Negative Bias Temperature Instability (NBTI) is an important lifetime reliability problem in microprocessors. SRAM-based structures within the processor are especially susceptible to NBTI since one of the PMOS devices in the memory cell always has an input of '0'. Previously proposed recovery techniques for SRAM cells aim to balance the...

    Provided By University of Virginia

  • White Papers // Dec 2010

    Modeling and Analyzing NBTI in the Presence of Process Variation

    With continuous scaling of transistors in each technology generation, NBTI and Process Variation (PV) have become very important silicon reliability problems for the microprocessor industry. In this paper, the authors develop an analytical model to capture the impact of NBTI in the presence of PV for use in architecture simulations....

    Provided By University of Virginia

  • White Papers // Jan 2011

    Bandwidth Allocation in Hexagonal Wireless Sensor Networks for Real-Time Communications

    This paper presents an algorithm for bandwidth allocation for delay-sensitive traffic in multi-hop wireless sensor networks. The solution considers both periodic as well as a periodic real-time traffic in an unified manner. The authors also present a distributed MAC protocol that conforms to the bandwidth allocation and thus satisfies the...

    Provided By University of Virginia

  • White Papers // Apr 2010

    Predictive Dependency Constraint Directed Self-Healing for Wireless Sensor Networks

    Wireless sensor networks are now being considered for mission critical applications, which are often largely unattended and need to operate reliably for years. However, due to the real world communication, sensing and failure realities, clock drift, and node faults, the system performance may degrade significantly over time. It is highly...

    Provided By University of Virginia

  • White Papers // Dec 2009

    ACR: Active Collision Recovery in Dense Wireless Sensor Networks

    Packet collision causes packet loss and wastes resources in wireless networks. It becomes even worse in dense WSNs, due to burst-traffic and congestion around sinks. In this paper, the authors propose a novel protocol to recover collided packets. The experiments on a testbed reveal that collisions between long packets and...

    Provided By University of Virginia

  • White Papers // Feb 2010

    Bundle: A Group Based Programming Abstraction for Cyber Physical Systems

    This paper describes a novel group based programming abstraction called a 'Bundle' for Cyber Physical Systems (CPS). Similar to other programming abstractions, a Bundle creates logical collections of sensing devices. However, previous abstractions were focused on Wireless Sensor Networks (WSN) and did not address key aspects of CPS. Bundles elevate...

    Provided By University of Virginia

  • White Papers // Jul 2009

    Enabling Task Parallelism in the CUDA Scheduler

    General purpose computing on Graphics Processing Units (GPUs) introduces the challenge of scheduling independent tasks on devices designed for data parallel or SPMD applications. This paper proposes an issue queue that merges workloads that would underutilize GPU processing resources such that they can be run concurrently on an NVIDIA GPU....

    Provided By University of Virginia

  • White Papers // Dec 2009

    Flashpower: A Detailed Power Model for Nand Flash Memory

    Flash memory is widely used in consumer electronics products, such as cell-phones and music players, and is increasingly displacing hard disk drives as the primary storage device in laptops, desktops, and even servers. There is a rich micro architectural design space for flash memory and there are several architectural options...

    Provided By University of Virginia

  • White Papers // Jun 2010

    A Performance Study for Iterative Stencil Loops on GPUs With Ghost Zone Optimizations

    Iterative Stencil Loops (ISLs) are used in many applications and tiling is a well-known technique to localize their computation. When ISLs are tiled across a parallel architecture, there are usually halo regions that need to be updated and exchanged among different Processing Elements (PEs). In addition, synchronization is often used...

    Provided By University of Virginia

  • White Papers // Oct 2009

    Avoiding Cache Thrashing Due to Private Data Placement in Last-Level Cache for Manycore Scaling

    Without high-bandwidth broadcast, large numbers of cores require a scalable point-to-point interconnect and a directory protocol. In such cases, a shared, inclusive Last Level Cache (LLC) can improve data sharing and avoid three way communications for shared reads. However, if inclusion encompasses thread-private data, two problems arise with the shared...

    Provided By University of Virginia

  • White Papers // Jan 2011

    A Performance Study of General Purpose Applications on Graphics Processors

    Graphic Processors Unit (GPUs), with many light-weight data-parallel cores, can provide substantial parallel computational power to accelerate general purpose applications. To best utilize the GPU's parallel computing resources, it is crucial to understand how GPU architectures and programming models can be applied to different categories of traditionally CPU applications. In...

    Provided By University of Virginia

  • White Papers // Jan 2011

    Accelerating Compute-Intensive Applications With GPUs and FPGAs

    Accelerators are special purpose processors designed to speed up compute-intensive sections of applications. Two extreme endpoints in the spectrum of possible accelerators are FPGAs and GPUs, which can often achieve better performance than CPUs on certain workloads. FPGAs are highly customizable, while GPUs provide massive parallel execution resources and high...

    Provided By University of Virginia

  • White Papers // Oct 2009

    Differentiating the Roles of IR Measurement and Simulation for Power and Temperature-Aware Design

    In temperature-aware design, the presence or absence of a heatsink fundamentally changes the thermal behavior with important design implications. In recent years, chip-level InfraRed (IR) thermal imaging has been gaining popularity in studying thermal phenomena and thermal management, as well as reverse-engineering chip power consumption. Unfortunately, IR thermal imaging needs...

    Provided By University of Virginia

  • White Papers // Jul 2009

    Autonomous Defenses for Security Attacks in Pervasive CPS Infrastructure

    Cyber-Physical Systems (CPS) integrate computation with sensing, control, and physical systems and will enable development of next-generation services and smart infrastructure across many application domains. However, a significant impediment to the use of CPS in trusted and trustworthy systems is their vulnerability to security attacks. Some properties of CPS that...

    Provided By University of Virginia

  • White Papers // Jun 2009

    Performance Modeling and Automatic Ghost Zone Optimization for Iterative Stencil Loops on GPUs

    Iterative Stencil Loops (ISLs) are used in many applications and tiling is a well-known technique to localize their computation. When ISLs are tiled across a parallel architecture, there are usually halo regions that need to be updated and exchanged among different Processing Elements (PEs). In addition, synchronization is often used...

    Provided By University of Virginia

  • White Papers // Apr 2010

    Object Localization Using RFID

    Object localization is a key primitive in pervasive computing environments, where numerous applications depend on the rapid and accurate position estimation of objects. This paper presents a general RFID - based localization framework that reliably determines the positions of objects with unprecedented accuracy and speed. This is achieved by varying...

    Provided By University of Virginia

  • White Papers // Dec 2009

    On Mitigating Covert Channels in RFID-Enabled Supply Chains

    In a competitive business environment, RFID technology can help a business to optimize its supply chain. However, it may also enable an adversary using covert channels to surreptitiously learn sensitive information about the supply chain of a target business. The authors argue that the tracking of tags and the compromising...

    Provided By University of Virginia

  • White Papers // Jun 2010

    Accelerating Enterprise Solid-State Disks With Non-Volatile Merge Caching

    Flash memory is now widely used in the design of Solid-State Disks (SSDs) as they are able to sustain significantly higher I/O rates than even high-performance hard disks, while using significantly less power. These characteristics make SSDs especially attractive for use in enterprise storage systems, and it is predicted that...

    Provided By University of Virginia

  • White Papers // Jun 2009

    Balancing Soft Error Coverage With Lifetime Reliability in Redundantly Multithreaded Processors

    Silicon reliability is a key challenge facing the micro-processor industry. Processors need to be designed such that they are resilient against both soft errors and lifetime reliability phenomena. However, techniques developed to address one class of reliability problems may impact other aspects of silicon reliability. In this paper, the authors...

    Provided By University of Virginia

  • White Papers // Dec 2010

    Relaxing Non-Volatility for Fast and Energy-Efficient STT-RAM Caches

    Spin-Transfer Torque RAM (STT-RAM) is an emerging non-volatile memory technology that is a potential universal memory that could replace SRAM in processor caches. This paper presents a novel approach for redesigning STT-RAM memory cells to reduce the high dynamic energy and slow write latencies. The authors lower the retention time...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Distributed Uplink Resource Allocation in Cognitive Radio Networks - Part II: Equilibria and Algorithms for Joint Access Point Selection and Power Allocation

    The main objective of this two part paper is to formulate and address the problem of distributed uplink resource allocation in multi-carrier Cognitive Radio Networks (CRN) with multiple Access Points (APs). When the APs operate on non-overlapping spectrum bands, such problem is essentially a joint spectrum decision and spectrum sharing...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Joint Distributed Access Point Selection and Power Allocation in Cognitive Radio Networks

    Spectrum management has been identified as a crucial step towards enabling the technology of the Cognitive Radio Network (CRN). Most of the current works dealing with spectrum management in the CRN focus on a single task of the problem, e.g., spectrum sensing, spectrum decision, spectrum sharing or spectrum mobility. In...

    Provided By University of Virginia

  • White Papers // Jan 2011

    Enviro-Track: Towards an Environmental Computing Paradigm for Distributed Sensor Networks

    Distributed sensor networks are quickly gaining recognition as viable embedded computing platforms. Current techniques for programming sensor networks are cumbersome, inflexible, and low-level. This paper introduces EnviroTrack, an object-based distributed middleware system that raises the level of programming abstraction by providing a convenient and powerful interface to the application developer...

    Provided By University of Virginia

  • White Papers // Aug 2010

    Characterization of User-Perceived Quality of Service (QoS) in Mobile Devices Using Network Pairwise Comparisons

    This paper presents a user-centric and application-specific QoS assessment methodology for cellular communication networks. Specifically, it uses the Analytic Hierarchy Process (AHP) to evaluate QoS as a multi-criteria decision problem that represents how well cellular networks' data services are perceived given particular sets of application classes and relative to other...

    Provided By University of Virginia

  • White Papers // May 2011

    Private Editing Using Untrusted Cloud Services

    The authors present a general methodology for protecting the confidentiality and integrity of user data for a class of on-line editing applications. The key insight is that many of these applications are designed to perform most of their data-dependent computation on the client side, so it is possible to maintain...

    Provided By University of Virginia

  • White Papers // Jun 2011

    GuardRails: A Data-Centric Web Application Security Framework

    Modern web application frameworks have made it easy to create powerful web applications. Developing a secure web application, however, still requires a developer to posses a deep understanding of security vulnerabilities and attacks. Even for experienced developers it is tedious, if not impossible, to find and eliminate all vulnerabilities. This...

    Provided By University of Virginia

  • White Papers // Sep 2009

    Privacy Through Noise: A Design Space for Private Identification

    To protect privacy in large systems, users should be able to authenticate against a central server without disclosing their identity to others. Private identification protocols based on public key cryptography are computationally expensive and cannot be implemented on small devices like RFID tags. Symmetric key protocols, on the other hand,...

    Provided By University of Virginia

  • White Papers // Feb 2011

    A Sub-0.5V Lattice-Based Public-Key Encryption Scheme for RFID Platforms in 130nm CMOS

    Implementing public-key cryptography on passive RFID tags is very challenging due to the limited die size and power available. Typical public-key algorithms require complex logical components such as modular exponentiation in RSA. The authors demonstrate the feasibility of implementing public-key encryption on low-power, low cost passive RFID tags to large-scale...

    Provided By University of Virginia

  • White Papers // Feb 2011

    Efficient Privacy-Preserving Biometric Identification

    The authors present an efficient matching protocol that can be used in many privacy-preserving biometric identification systems in the semi-honest setting. The most general technical contribution is a new backtracking protocol that uses the byproduct of evaluating a garbled circuit to enable efficient oblivious information retrieval. They also present a...

    Provided By University of Virginia