Iowa State University

Displaying 1-40 of 156 results

  • White Papers // Sep 2013

    Energy Saving Techniques for Phase Change Memory (PCM)

    In recent years, the energy consumption of computing systems has increased and a large fraction of this energy is consumed in main memory. Towards this, researchers have proposed use of non-volatile memory, such as Phase Change Memory (PCM), which has low read latency and power; and nearly zero leakage power....

    Provided By Iowa State University

  • White Papers // May 2013

    Replication Based Storage Systems With Local Repair

    The authors consider the design of regenerating codes for distributed storage systems that enjoy the property of local, exact and uncoded repair, i.e., upon failure, a node can be regenerated by simply downloading packets from the surviving nodes and the number of surviving nodes contacted is strictly smaller than the...

    Provided By Iowa State University

  • White Papers // Apr 2013

    Reduce, Reuse, Recycle (R3): a Design Methodology for Sparse Matrix Vector Multiplication on Reconfigurable Platforms

    Sparse Matrix Vector multiplication (SpMV) is an important computational kernel in many scientific computing applications. Pipelining multiply-accumulate operations shifts SpMV from a computationally bounded kernel to an I/O bounded kernel. In this paper, the authors propose design methodology and hardware architecture for SpMV that seeks to utilize system memory bandwidth...

    Provided By Iowa State University

  • White Papers // Feb 2013

    A Multi-Faceted Approach to FPGA-Based Trojan Circuit Detection

    In recent years, the vulnerability of chips to hardware Trojans has garnered a great deal of attention. Three general approaches to detecting Trojans embedded in FPGA circuits were explored in the context of the 2012 CSAW embedded systems challenge: functional testing, power analysis, and direct analysis of the bit-file. These...

    Provided By Iowa State University

  • White Papers // Oct 2012

    Repairable Replication-Based Storage Systems Using Resolvable Designs

    The authors consider the design of regenerating codes for distributed storage systems at the Minimum Bandwidth Regeneration (MBR) point. The codes allow for a repair process that is exact and uncoded, but table-based. These codes were introduced in prior work and consist of an outer MDS code followed by an...

    Provided By Iowa State University

  • White Papers // Aug 2012

    Design and Evaluation of a Delay-Based FPGA Physically Unclonable Function

    A new Physically Unclonable Function (PUF) variant was developed on an FPGA, and its quality evaluated. It is conceptually similar to PUFs developed using standard SRAM cells, except it utilizes general FPGA reconfigurable fabric, which offers several advantages. Comparison between the authors approach and other PUF designs indicates that their...

    Provided By Iowa State University

  • White Papers // Aug 2012

    ZigBee-Assisted Power Saving Management for Mobile Devices

    WiFi transmission can consume much energy on energy-constrained mobile devices. To improve energy efficiency, the Power Saving Management (PSM) has been standardized and applied. The standard PSM, however, may not deliver satisfactory energy efficiency in many cases as the wakeup strategy adopted by it cannot adapt dynamically to traffic pattern...

    Provided By Iowa State University

  • White Papers // Jul 2012

    Impact of Network Conditions on Delay-Stable Communications in Closed Industrial Control Networks

    To properly operate closed industrial control networks, it is required that communication with nearly constant delay bounds be supported. The authors introduced FlexTDMA in order to provide this support, and with minimal delay-jitter in an asynchronous network, under unicast communication. In this paper the authors consider how periodic on-off traffic...

    Provided By Iowa State University

  • White Papers // Jul 2012

    Delay-Stable Communications in Simultaneous Multicast Networks

    To properly operate closed industrial control networks, it is required that communication with nearly constant delay bounds be supported. The authors introduced FlexTDMA in order to provide this support, and with minimal delay-jitter in an asynchronous network, under unicast communication. In this paper, the authors consider providing this support for...

    Provided By Iowa State University

  • White Papers // May 2012

    Trustworthiness of Random Network Coded Information in Untrustworthy Networks

    The authors examine the trustworthiness of random network coded information in untrustworthy networks, where the network nodes provide false data purposely or unknowingly and data transmissions are subject to channel errors. The trustworthiness of information x is defined as the probability of x being true. They show that the trustworthiness...

    Provided By Iowa State University

  • White Papers // May 2012

    An Ad Hoc Group Signature Scheme for Accountable and Anonymous Access to Outsourced Data

    This paper presents a group signature scheme called adhoc sign for dynamically formed groups, to support accountable and anonymous access to outsourced data. Each user is assigned a certain set of attributes and the secrets associated with these attributes when joining the system; the access to outsourced data is regulated...

    Provided By Iowa State University

  • White Papers // Apr 2012

    Spectrum Decision for Efficient Routing in Cognitive Radio Network

    The Cognitive Radio (CR) nodes in a Cognitive Radio Network (CRN) do not have license to use specific spectrum band. Instead, they use the spectrum bands of the licensed Primary Users (PU) without interfering with the PU. When the PU becomes active, interfering CRs should leave to another available spectrum...

    Provided By Iowa State University

  • White Papers // Apr 2012

    Dynamic Test Input Generation for Database Applications to Achieve High Mutation Score

    Automatic generation of test cases for database applications has attracted researchers from both academia and industry. Typically in database application, the quality of test cases for the host language (e.g., Java) is evaluated on the basis of the number of lines, statements and blocks covered by the test cases, whereas,...

    Provided By Iowa State University

  • White Papers // Mar 2012

    Hybrid Network-Erasure Coding Protection of Multi-Source, Multi-Sink Multicast Sessions in WSNs

    In this paper, the authors consider the problem of providing fault tolerant operation for multicast networks with multiple sources, e.g., sensors, and delivering data to a pre-defined set of destinations, e.g., sinks. They propose an algorithm that combines network and erasure coding to provide resilience against a predefined number of...

    Provided By Iowa State University

  • White Papers // Feb 2012

    Field Size of Random Network Coding in Untrustworthy Networks

    The authors examine the probability of symbol error and the throughput with random network coding in untrustworthy networks, where the network nodes provide false data purposely or unknowingly and the information transmission is subject to channel error. They show that there exists an optimum field size that maximizes the throughput...

    Provided By Iowa State University

  • White Papers // Jan 2012

    LBA: Lifetime Balanced Data Aggregation in Low Duty Cycle Sensor Networks

    This paper proposes LBA, a lifetime balanced data aggregation scheme for asynchronous and duty cycle sensor networks under an application-specific requirement of end-to-end data delivery delay bound. In contrast to existing aggregation schemes that focus on reducing the energy consumption and extending the operational lifetime of each individual node, LBA...

    Provided By Iowa State University

  • White Papers // Nov 2011

    Modeling Web Usage Profiles of Cloud Services for Utility Cost Analysis

    Early proponents of public cloud computing have come to identify cost savings a key factor for adoption. However, the adoption and hosting of a web application in the cloud does not provide any such guarantees. This is in part due to the utility pricing model that dictates the cost of...

    Provided By Iowa State University

  • White Papers // Nov 2011

    ZigBee-Assisted WiFi Transmission for Multi-Interface Mobile Devices

    It has been common for a mobile device to have WiFi and Bluetooth interfaces. As the ZigBee technology becomes more mature, it will not be surprising to see the ZigBee interface commonly embedded in mobile devices together with WiFi and other interfaces in the near future. To leverage the ZigBee...

    Provided By Iowa State University

  • White Papers // Sep 2011

    Real Interference Alignment and Degrees of Freedom Region of Wireless X Networks

    The authors consider a single hop wireless X network with K transmitters and J receivers, all with single antenna. Each transmitter conveys for each receiver an independent message. The channel is assumed to have constant coefficients. They develop interference alignment scheme for this setup and derived several achievable degrees of...

    Provided By Iowa State University

  • White Papers // Aug 2011

    Distributed Power Control and Coding-Modulation Adaptation in Wireless Networks Using Annealed Gibbs Sampling

    In wireless networks, the transmission rate of a link is determined by received signal strength, interference from simultaneous transmissions, and available coding-modulation schemes. Rate allocation is a key problem in wireless network design, but a very challenging problem because: wireless interference is global, i.e., a transmission interfere all other simultaneous...

    Provided By Iowa State University

  • White Papers // Aug 2011

    J-RoC: A Joint Routing and Charging Scheme to Prolong Sensor Network Lifetime

    The emerging wireless charging technology creates a controllable and perpetual energy source to provide wireless power over distance. Schemes have been proposed to make use of wireless charging to prolong the sensor network lifetime. Unfortunately, existing schemes only passively replenish sensors that are deficient in energy supply, and cannot fully...

    Provided By Iowa State University

  • White Papers // Aug 2011

    Efficient Spectrum Searching and Monitoring in Cognitive Radio Network

    Wireless spectrum is highly underutilized, where significant parts of it are used only for some time periods in an on/off manner and with large geographical variations. Such low utilization in spectrum usage resulted from currently deployed static frequency allocation policy. Apparently, in order to increase wireless spectrum utilization, more flexible...

    Provided By Iowa State University

  • White Papers // Aug 2011

    Heterogeneity-Aware Design for Automatic Detection of Problematic Road Conditions

    Improving driving safety is one major objective of forming Vehicular Ad hoc NETworks (VANETs). Existing VANETs usually assume drivers detect and report safety-related road conditions. However, drivers may not be willing to perform these duties; even they are, these duties may distract them from driving and thus make driving unsafe....

    Provided By Iowa State University

  • White Papers // Aug 2011

    Circumventing a Ring Oscillator Approach to FPGA-Based Hardware Trojan Detection

    Ring oscillators are commonly used as a locking mechanism that binds a hardware design to a specific area of silicon within an Integrated Circuit (IC). This locking mechanism can be used to detect malicious modifications to the hardware design, also known as a hardware Trojan, in situations where such modifications...

    Provided By Iowa State University

  • White Papers // Aug 2011

    A Wireless Sensor Network for Precision Agriculture and Its Performance

    The use of wireless sensor networks is essential for implementation of information and control technologies in precision agriculture. The authors present their design of network stack for such an application where sensor nodes periodically collect data from fixed locations in a field. Their design of the PHYsical (PHY) layer consists...

    Provided By Iowa State University

  • White Papers // Jun 2011

    An Automatic, Time-Based, Secure Pairing Protocol for Passive RFID

    This paper introduces the Adopted-Pet (AP) protocol, an automatic (i.e. requiring no human interaction) secure pairing protocol, adequate for the pairing between a passive RFID tag and a reader. Most pairing protocols rely for their security on a certain advantage that the legitimate devices have over any malicious users. Such...

    Provided By Iowa State University

  • White Papers // Jun 2011

    A Light-Weight Solution to Preservation of Access Pattern Privacy in Un-Trusted Clouds

    Cloud computing is a new computing paradigm that is gaining in-creased popularity. More and more sensitive user data are stored in the cloud. The privacy of users' access pattern to the data should be protected to prevent un-trusted cloud servers from inferring users' private information or launching stealthy attacks. Meanwhile,...

    Provided By Iowa State University

  • White Papers // May 2011

    Hardware Architecture for Simultaneous Arithmetic Coding and Encryption

    Arithmetic coding is increasingly being used in upcoming image and video compression standards such as JPEG2000, and MPEG-4/H.264 AVC and SVC standards. It provides an efficient way of loss-less compression and recently, it has been used for joint compression and encryption of video data. In this paper, the authors present...

    Provided By Iowa State University

  • White Papers // May 2011

    Global Biofuel Expansion And The Demand For Brazilian Land: Intensification Versus Expansion

    The authors use a spatially disaggregated model of Brazilian agriculture to assess the implications of global biofuel expansion on Brazilian land usage at the regional level. This Brazilian model is part of the FAPRI agricultural modeling system, a multimarket, multi-commodity international agricultural model, used to quantify the emergence of biofuels...

    Provided By Iowa State University

  • White Papers // Apr 2011

    Architecture for Simultaneous Coding and Encryption Using Chaotic Maps

    In this paper, the authors discuss an interpretation of arithmetic coding using chaotic maps. They present a hardware implementation using 64 bit fixed point arithmetic on Virtex- 6 FPGA (with and without using DSP slices). The encoder resources are slightly higher than a traditional AC encoder, but there are savings...

    Provided By Iowa State University

  • White Papers // Apr 2011

    Performance Modeling and Simulation Studies of MAC Protocols in Sensor Network Performance

    The use of wireless sensor networks is essential for implementation of information and control technologies in precision agriculture. The authors present their design of network stack for such an application where sensor nodes periodically collect data from fixed locations in a field. Their design of the PHYsical (PHY) layer consists...

    Provided By Iowa State University

  • White Papers // Apr 2011

    Teaching Graphics Processing and Architecture using a Hardware Prototyping Approach

    Since its introduction over two decades ago, graphics hardware has continued to evolve to improve rendering performance and increase programmability. While most undergraduate courses in computer graphics focus on rendering algorithms and programming APIs, the authors have recently created an undergraduate senior elective course that focuses on graphics processing and...

    Provided By Iowa State University

  • White Papers // Mar 2011

    Interference Alignment and Degrees of Freedom Region of Cellular Sigma Channel

    The authors investigate the Degrees of Freedom (DoF) region of a cellular network, where the cells can have overlapping areas. Within an overlapping area, the mobile users can access multiple base stations. They consider a case where there are two base stations both equipped with multiple antennas. The mobile stations...

    Provided By Iowa State University

  • White Papers // Feb 2011

    Superposition Noisy Network Coding

    The authors present a superposition coding scheme for communication over a network, which combines partial decode and forward and noisy network coding. This hybrid scheme is termed as superposition noisy network coding. The scheme is designed and analyzed for single relay channel, single source multicast network and multiple source multicast...

    Provided By Iowa State University

  • White Papers // Feb 2011

    Uplink Channel Assignment in Cognitive Radio WMNs Using Physical Layer Network Coding

    In this paper, the authors introduce a low overhead scheme for the uplink channel allocation within a single cell of Cognitive Radio Wireless Mesh Network (CR-WMNs). The scheme does not rely on using a Common Control Channel (CCC). The mechanism is based on Physical layer Network Coding (PNC), in which...

    Provided By Iowa State University

  • White Papers // Jan 2011

    Content-Based Network Adaptive Wireless Transmission of Remote Surveillance Video

    Due to advances in network technology and the prevalence of wireless networks, it has become possible to realize Remote Video Surveillance (RVS) applications as a low cost system using existing infrastructure. However such applications require enormous bandwidth for video transmission and a serious bottleneck is the non-availability of required bandwidth,...

    Provided By Iowa State University

  • White Papers // Jan 2011

    Secure DVR Protocol Using Factual Correctness

    The routing protocols in use today operate on implicit trust among the different routing elements. Specifically, the Distance Vector Routing (DVR) protocols compute updates and routing tables in a distributed manner, and consequently fail to ensure the factual correctness of the routing updates, which is very critical for secure routing....

    Provided By Iowa State University

  • White Papers // Jan 2011

    Eliminating SQL Injection Attacks - A Transparent Defense Mechanism

    The widespread adoption of web services as an instant means of information dissemination and various other transactions, has essentially made them a key component of today's Internet infrastructure. Web-based systems comprise both of infrastructure components and of application specific code. Various organizations have started extensively deploying Intrusion Detection/Prevention Systems and...

    Provided By Iowa State University

  • White Papers // Jan 2011

    Assembling Composite Web Services From Autonomous Components

    Web services are fast emerging as the technology of choice to build distributed information systems in multiple domains including e-Business and e-Science. An important challenge is to develop methodologies and tools that enable (semi-) automatic composition of services by taking into account the functional, non-functional and behavioral requirements of the...

    Provided By Iowa State University

  • White Papers // Jan 2011

    Local and On-the-Fly Choreography-Based Web Service Composition

    The authors present a goal-directed, local and on-the-fly algorithm for verifying the existence of and synthesizing a choreographer for Web service composition. They use i/o-automata to represent the (existing/component) services, the desired functionality of the composition, and a choreographer to achieve the desired service by composing the existing ones. As...

    Provided By Iowa State University

  • White Papers // May 2009

    Encoding of Network Protection Codes Against Link and Node Failures Over Finite Fields

    Link and node failures are common two fundamental problems that affect operational networks. Hence, protection of communication networks is essential to increase their reliability, performance, and operations. Much research work has been done to protect against link and node failures, and to provide reliable solutions based on pre-defined provision or...

    Provided By Iowa State University

  • White Papers // Aug 2010

    Protection Against Link Errors and Failures Using Network Coding

    The authors propose a network-coding based scheme to protect multiple bidirectional unicast connections against adversarial errors and failures in a network. The network consists of a set of bidirectional primary path connections that carry the uncoded traffic. The end nodes of the bidirectional connections are connected by a set of...

    Provided By Iowa State University

  • White Papers // Aug 2009

    On Delay Constrained Multicast Capacity of Large-Scale Mobile Ad-Hoc Networks

    Wireless technology has provided an infrastructure-free and fast-deployable method to establish communication, and has inspired many emerging networks including Mobile Ad hoc NETworks (MANETs), which has broad potential applications in personal area networks, emergency/rescue operations, and military battlefield applications. For example, the ZebraNet is a MANET used to monitor and...

    Provided By Iowa State University

  • White Papers // Oct 2009

    Assessing the Performance of Macromolecular Sequence Classifiers

    Machine learning approaches offer some of the most cost-effective approaches to building predictive models (e.g., classifiers) in a broad range of applications in computational biology. Comparing the effectiveness of different algorithms requires reliable procedures for accurately assessing the performance (e.g., accuracy, sensitivity, and specificity) of the resulting predictive classifiers. The...

    Provided By Iowa State University

  • White Papers // Mar 2009

    Package-Based Description Logics

    The success of the world wide web can be partially attributed to the net-work effect : The absence of central control on the content and the organization of the web allows thousands of independent actors to contribute resources (web pages) that are interlinked to form the web. Ongoing efforts to...

    Provided By Iowa State University

  • White Papers // Sep 2009

    The Asymptotic Behavior of Minimum Buffer Size Requirements in Large P2P Streaming Networks

    The growth of real-time content streaming over the Internet has resulted in the use of Peer-To-Peer (P2P) approaches for scalable content delivery. In such P2P streaming systems, each peer maintains a playout buffer of content chunks which it attempts to fill by contacting other peers in the network. The objective...

    Provided By Iowa State University

  • White Papers // Sep 2009

    Memory Consistency Conditions for Self-Assembly Programming

    Perhaps the two most significant theoretical questions about the programming of self-assembling agents are: necessary and sufficient conditions to produce a unique terminal assembly, and error correction. The authors address both questions, by reducing two well-studied models of tile assembly to models of Distributed Shared Memory (DSM), in order to...

    Provided By Iowa State University

  • White Papers // Sep 2009

    Fast Algorithm for Finding Unicast Capacity of Linear Deterministic Wireless Relay Networks

    The deterministic channel model for wireless relay networks proposed by Avestimehr, Diggavi and Tse '07 has captured the broadcast and inference nature of wireless communications and has been widely used in approximating the capacity of wireless relay networks. The authors generalized the max-flow min-cut theorem to the linear deterministic wireless...

    Provided By Iowa State University

  • White Papers // Sep 2009

    Feedback-Based Collaborative Secrecy Encoding Over Binary Symmetric Channels

    In this paper the authors propose a feedback scheme for transmitting secret messages between two legitimate parties, over an eavesdropped communication link. Relative to Wyner's traditional encoding scheme, the feedback-based encoding often yields larger rate-equivocation regions and achievable secrecy rates. More importantly, by exploiting the channel randomness inherent in the...

    Provided By Iowa State University

  • White Papers // Oct 2009

    Domain Decomposition Based High Performance Parallel Computing

    The study deals with the parallelization of finite element based Navier-Stokes codes using domain decomposition and state-of-art sparse direct solvers. There has been significant improvement in the performance of sparse direct solvers. Parallel sparse direct solvers are not found to exhibit good scalability. Hence, the parallelization of sparse direct solvers...

    Provided By Iowa State University

  • White Papers // May 2010

    ISO Net Surplus Collection And Allocation In Restructured Wholesale Power Markets

    This paper uses 5-bus and 30-bus test cases to explore ISO net surplus (congestion rent) collections and allocations in wholesale power markets with grid congestion managed by Locational Marginal prices (LMPs). Price-sensitivity of demand and generator learning capabilities are taken as experimental treatment factors. A key finding is that conditions...

    Provided By Iowa State University

  • White Papers // Jan 2011

    Content-Based Network Adaptive Wireless Transmission of Remote Surveillance Video

    Due to advances in network technology and the prevalence of wireless networks, it has become possible to realize Remote Video Surveillance (RVS) applications as a low cost system using existing infrastructure. However such applications require enormous bandwidth for video transmission and a serious bottleneck is the non-availability of required bandwidth,...

    Provided By Iowa State University

  • White Papers // May 2011

    Global Biofuel Expansion And The Demand For Brazilian Land: Intensification Versus Expansion

    The authors use a spatially disaggregated model of Brazilian agriculture to assess the implications of global biofuel expansion on Brazilian land usage at the regional level. This Brazilian model is part of the FAPRI agricultural modeling system, a multimarket, multi-commodity international agricultural model, used to quantify the emergence of biofuels...

    Provided By Iowa State University

  • White Papers // Sep 2011

    Real Interference Alignment and Degrees of Freedom Region of Wireless X Networks

    The authors consider a single hop wireless X network with K transmitters and J receivers, all with single antenna. Each transmitter conveys for each receiver an independent message. The channel is assumed to have constant coefficients. They develop interference alignment scheme for this setup and derived several achievable degrees of...

    Provided By Iowa State University

  • White Papers // Jun 2009

    An Effective Method for Combating Malicious Scripts Clickbots

    Online advertising has been suffering serious click fraud problem. Fraudulent publishers can generate false clicks using malicious scripts embedded in their web pages. Even widely-used security techniques like iframe cannot prevent such attack. In this paper, the authors propose a framework and associated methodologies to automatically and quickly detect and...

    Provided By Iowa State University

  • White Papers // Aug 2011

    Distributed Power Control and Coding-Modulation Adaptation in Wireless Networks Using Annealed Gibbs Sampling

    In wireless networks, the transmission rate of a link is determined by received signal strength, interference from simultaneous transmissions, and available coding-modulation schemes. Rate allocation is a key problem in wireless network design, but a very challenging problem because: wireless interference is global, i.e., a transmission interfere all other simultaneous...

    Provided By Iowa State University

  • White Papers // Aug 2009

    Health Insurance Coverage Estimates For Iowa

    The U.S. Census Bureau recently released new model?]based estimates of the size of the uninsured population for all counties and states in the United States. These data, produced under the Small Area Health Insurance Estimates (SAHIE) program, describe characteristics of the uninsured population by age, sex, and income level for...

    Provided By Iowa State University

  • White Papers // Feb 2011

    Uplink Channel Assignment in Cognitive Radio WMNs Using Physical Layer Network Coding

    In this paper, the authors introduce a low overhead scheme for the uplink channel allocation within a single cell of Cognitive Radio Wireless Mesh Network (CR-WMNs). The scheme does not rely on using a Common Control Channel (CCC). The mechanism is based on Physical layer Network Coding (PNC), in which...

    Provided By Iowa State University

  • White Papers // May 2010

    Debt- Versus Equity-financing In Auction Designs

    A social planner wishes to launch a project but the contenders capable of running the project are cash-constrained and may default. To signal their capabilities, the contenders may finance their bids through debt or equity, depending on the mechanism chosen by the social planner. When moral hazard is absent, it...

    Provided By Iowa State University

  • White Papers // Apr 2010

    Optimized Sink Mobility for Energy and Delay Efficient Data Collection in FWSNs

    Network fragmentation is a potential problem in Wireless Sensor Networks (WSNs) due to many reasons like, node failures or environmental conditions (obstacles) that prevent connected deployments. One approach to cope with this problem is to have a Mobile Sink node (MS) patrol the network field and collect the data from...

    Provided By Iowa State University

  • White Papers // Jun 2009

    Firing Cost And Firm Size: A Study Of Sri Lanka's Severance Pay System

    Sri Lanka's Termination of Employment of Workmen Act (TEWA) requires that firms with 15 or more employees justify layoffs and provide generous severance pay to displaced workers, with smaller firms being exempted. Although formally subject to TEWA, firms in Export Processing Zones (EPZs) may have been partially exempt from TEWA...

    Provided By Iowa State University

  • White Papers // Dec 2009

    Low-Complexity Scheduling Algorithms for Multi-Channel Downlink Wireless Networks

    This paper considers the problem of designing scheduling algorithms for multi-channel (e.g., OFDM) wireless downlink networks with n users/OFDM sub-channels. For this system, while the classical MaxWeight algorithm is known to be throughput-optimal, its buffer-overflow performance is very poor (formally, the authors show it has zero rate function in their...

    Provided By Iowa State University

  • White Papers // Aug 2009

    Survivability Strategies in Multihop Wireless Networks

    Survivability is an important network characteristic that provides a certain level of data delivery guarantees. The degree of survivability is usually governed by the data transfer mechanism or protocol that delivers data from source to destination. In this paper, the authors survey and discuss a variety of survivability issues, challenges...

    Provided By Iowa State University

  • White Papers // May 2009

    A Power-Efficient Scheme for Securing Multicast in Hierarchical Sensor Networks

    Hierarchical architectures are more and more widely adopted for organizing wireless sensor networks. In such architectures, middle-tier nodes take important roles, and preventing a malicious node from impersonating a middle-tier node and injecting falsified messages becomes critical. In this paper, the authors propose an energy efficient, distributed scheme to secure...

    Provided By Iowa State University

  • White Papers // Mar 2010

    Mandates, Tax Credits, And Tariffs: Does The U.S. Biofuels Industry Need Them All?

    Expanded mandates under the Renewable Fuel Standard provide ethanol and biodiesel producers a guaranteed future market at volumes that exceed what they have produced in the past. Despite having these mandates in place, biofuel producers continue to support tax credits and ethanol import tariffs. An examination of how the new...

    Provided By Iowa State University

  • White Papers // Aug 2009

    On-Demand Node Reclamation and Replacement for Guaranteed Area Coverage in Long-Lived Sensor Networks

    To achieve required sensing coverage for a very long period of time is an important and challenging problem in sensor network design. Recently, Tong et al. have proposed a Node Replacement and Reclamation (NRR) strategy, and designed an Adaptive Rendezvous-based Two-tier Scheduling (ARTS) scheme. However, the ARTS scheme only considers...

    Provided By Iowa State University

  • White Papers // Oct 2010

    Effects Of Credit Constraints On Productivity And Rural Household Income In China

    Agricultural production is strongly conditioned by the fact that inputs are transformed into outputs with considerable time lags, causing the rural household to balance its budget during the season when there are high expenditures for input purchases and consumption and few revenues. With limited access to credit, the budget balance...

    Provided By Iowa State University

  • White Papers // Jun 2010

    How Wireless Power Charging Technology Affects Sensor Network Deployment and Routing

    As wireless power charging technology emerges, some basic principles in sensor network design are changed accordingly. Existing sensor node deployment and data routing strategies cannot exploit wireless charging technology to minimize overall energy consumption. Hence, in this paper, the authors investigate the impact of wireless charging technology on sensor network...

    Provided By Iowa State University

  • White Papers // Apr 2009

    Land-Use Credits To Corn Ethanol: Accounting For Distillers Dried Grains With Solubles As A Feed Substitute In Swine Rations

    Many studies on the impact of biofuels on greenhouse gas emissions do not consider indirect land-use change and land use avoided because of co-products utilization. This paper provides estimates of the land-use credit for corn ethanol when its by-product - Distillers Dried Grains with Solubles (DDGS) - is used in...

    Provided By Iowa State University

  • White Papers // Aug 2011

    J-RoC: A Joint Routing and Charging Scheme to Prolong Sensor Network Lifetime

    The emerging wireless charging technology creates a controllable and perpetual energy source to provide wireless power over distance. Schemes have been proposed to make use of wireless charging to prolong the sensor network lifetime. Unfortunately, existing schemes only passively replenish sensors that are deficient in energy supply, and cannot fully...

    Provided By Iowa State University

  • White Papers // Jan 2009

    Scheduling in Mobile Wireless Networks With Topology and Channel-State Uncertainty

    The authors study throughput-optimal scheduling/routing over mobile ad-hoc networks with time-varying (fading) channels. Traditional back-pressure algorithms (based on the work by Tassiulas and Ephremides) require instantaneous network state (topology, queues-lengths, and fading channel-state) in order to make scheduling/routing decisions. However, such instantaneous network-wide (global) information is hard to come by...

    Provided By Iowa State University

  • White Papers // Aug 2011

    A Wireless Sensor Network for Precision Agriculture and Its Performance

    The use of wireless sensor networks is essential for implementation of information and control technologies in precision agriculture. The authors present their design of network stack for such an application where sensor nodes periodically collect data from fixed locations in a field. Their design of the PHYsical (PHY) layer consists...

    Provided By Iowa State University

  • White Papers // Dec 2009

    Approximation Algorithms for Many-to-Many Traffic Grooming in WDM Mesh Networks

    A large number of network applications today allow several users to interact together using the many-to-many service mode. In many-to-many communication, also referred to as group communication, a session consists of a group of users (the authors refer to them as members), where each member transmits its traffic to all...

    Provided By Iowa State University

  • White Papers // Oct 2012

    Repairable Replication-Based Storage Systems Using Resolvable Designs

    The authors consider the design of regenerating codes for distributed storage systems at the Minimum Bandwidth Regeneration (MBR) point. The codes allow for a repair process that is exact and uncoded, but table-based. These codes were introduced in prior work and consist of an outer MDS code followed by an...

    Provided By Iowa State University

  • White Papers // Apr 2012

    Spectrum Decision for Efficient Routing in Cognitive Radio Network

    The Cognitive Radio (CR) nodes in a Cognitive Radio Network (CRN) do not have license to use specific spectrum band. Instead, they use the spectrum bands of the licensed Primary Users (PU) without interfering with the PU. When the PU becomes active, interfering CRs should leave to another available spectrum...

    Provided By Iowa State University

  • White Papers // Jul 2012

    Impact of Network Conditions on Delay-Stable Communications in Closed Industrial Control Networks

    To properly operate closed industrial control networks, it is required that communication with nearly constant delay bounds be supported. The authors introduced FlexTDMA in order to provide this support, and with minimal delay-jitter in an asynchronous network, under unicast communication. In this paper the authors consider how periodic on-off traffic...

    Provided By Iowa State University

  • White Papers // Jul 2012

    Delay-Stable Communications in Simultaneous Multicast Networks

    To properly operate closed industrial control networks, it is required that communication with nearly constant delay bounds be supported. The authors introduced FlexTDMA in order to provide this support, and with minimal delay-jitter in an asynchronous network, under unicast communication. In this paper, the authors consider providing this support for...

    Provided By Iowa State University

  • White Papers // Mar 2012

    Hybrid Network-Erasure Coding Protection of Multi-Source, Multi-Sink Multicast Sessions in WSNs

    In this paper, the authors consider the problem of providing fault tolerant operation for multicast networks with multiple sources, e.g., sensors, and delivering data to a pre-defined set of destinations, e.g., sinks. They propose an algorithm that combines network and erasure coding to provide resilience against a predefined number of...

    Provided By Iowa State University

  • White Papers // Aug 2011

    Efficient Spectrum Searching and Monitoring in Cognitive Radio Network

    Wireless spectrum is highly underutilized, where significant parts of it are used only for some time periods in an on/off manner and with large geographical variations. Such low utilization in spectrum usage resulted from currently deployed static frequency allocation policy. Apparently, in order to increase wireless spectrum utilization, more flexible...

    Provided By Iowa State University

  • White Papers // Apr 2011

    Performance Modeling and Simulation Studies of MAC Protocols in Sensor Network Performance

    The use of wireless sensor networks is essential for implementation of information and control technologies in precision agriculture. The authors present their design of network stack for such an application where sensor nodes periodically collect data from fixed locations in a field. Their design of the PHYsical (PHY) layer consists...

    Provided By Iowa State University