Uppror Media Group

Displaying 1-40 of 42 results

  • White Papers // Nov 2013

    Verification of Heap Manipulating Programs with Ordered Data by Extended Forest Automata

    The authors present a general framework for verifying programs with complex dynamic linked data structures whose correctness depends on ordering relations between stored data values. The underlying formalism of their framework is that of Forest Automata (FA), which has previously been developed for verification of heap-manipulating programs. They extend FA...

    Provided By Uppror Media Group

  • White Papers // Sep 2013

    General and Efficient Response Time Analysis for EDF Scheduling

    Response Time Analysis (RTA) is one of the key problems in real-time system design. This paper proposes new RTA methods for EDF scheduling, with general system models where workload and resource availability are represented by request/demand bound functions and supply bound functions. The main idea is to derive response time...

    Provided By Uppror Media Group

  • White Papers // Sep 2013

    Combinatorial Abstraction Refinement for Feasibility Analysis

    The traditional periodic workload model for hard real-time systems has been extended by more expressive models in recent years. These models based on different classes of directed graphs allow modeling of structures like frames, branching and loops. With more expressiveness comes higher complexity of the associated analysis problems. Feasibility of...

    Provided By Uppror Media Group

  • White Papers // Jul 2013

    Skew Handling in Aggregate Streaming Queries on GPUs

    Now-a-days, the data to be processed by database systems has grown so large that any conventional, centralized technique is inadequate. At the same time, General Purpose computation on GPU (GPGPU) recently has successfully drawn attention from the data management community due to its ability to achieve significant speed-ups at a...

    Provided By Uppror Media Group

  • White Papers // Apr 2013

    Electronically-Switched Directional Antennas for Wireless Sensor Networks: A Full-Stack Evaluation

    The authors study the benefits of Electronically-Switched Directional (ESD) antennas in Wireless Sensor Networks (WSNs). ESD antennas have proved beneficial in cellular and ad-hoc networks, by increasing the communication range and by alleviating contention in directions other than the destination. The advantages in WSNs are, however, still largely to be...

    Provided By Uppror Media Group

  • White Papers // Mar 2013

    Models for Real-Time Workload: A Survey

    In this paper, the authors provide a survey on task models to characterize real-time workloads at different levels of abstraction for the design and analysis of real-time systems. It covers the classic periodic and sporadic models by Liu and Layland et al., their extensions to describe recurring and branching structures...

    Provided By Uppror Media Group

  • White Papers // Jan 2013

    An Integrated Specification and Verification Technique for Highly Concurrent Data Structures

    The authors present a technique for automatically verifying safety properties of concurrent programs, in particular programs which rely on subtle dependencies of local states of different threads, such as lock-free implementations of stacks and queues in an environment without garbage collection. Their technique addresses the joint challenges of infinite-state specifications,...

    Provided By Uppror Media Group

  • White Papers // Dec 2012

    Understanding Link Dynamics in Wireless Sensor Networks With Dynamically Steerable Directional Antennas

    By radiating the power in the direction of choice, Electronically Switched Directional (ESD) antennas can reduce network contention and avoid packet loss. There exists some ESD antennas for wireless sensor networks, but so far researchers have mainly evaluated their directionality. There are no studies regarding the link dynamics of ESD...

    Provided By Uppror Media Group

  • White Papers // Jul 2012

    Monotonic Abstraction for Programs with Multiply-Linked Structures

    The authors investigate the use of monotonic abstraction and back-ward reachability analysis as means of performing shape analysis on programs with multiply pointed structures. By encoding the heap as a vertex- and edge-labeled graph, they can model the low level behavior exhibited by programs written in the C programming language....

    Provided By Uppror Media Group

  • White Papers // May 2012

    Measurement-Based Evaluation of Robust Linear Precoding for Downlink CoMP

    The authors study the design and evaluation of joint processing Coordinated Multi-Point (CoMP) downlink transmission. Precoders will then be designed based on outdated Channel State Information (CSI), so interference cannot be eliminated completely as by an ideal Zero-Forcing (ZF) solution. They here strive to design and evaluate realistic linear transmit...

    Provided By Uppror Media Group

  • White Papers // May 2012

    Avoiding Overages by Deferred Aggregate Demand for PEV Charging on the Smart Grid

    The authors model the aggregate overnight demand for electricity by a large community of (possibly hybrid) Plug-in Electric Vehicles (PEVs) each of whose power demand follows a prescribed profile and is interruptible. Rather than a spot-price system for household consumers (which would necessarily need to be operated by automated means...

    Provided By Uppror Media Group

  • White Papers // Apr 2012

    Bounding and Shaping the Demand of Mixed-Criticality Sporadic Tasks

    The authors derive demand-bound functions for mixed-criticality sporadic tasks, and use these to determine EDF-schedulability. Tasks have different demand-bound functions for each criticality mode. They show how to shift execution demand from high-to low-criticality mode by tuning the relative deadlines. This paper allows the user to shape the demand characteristics...

    Provided By Uppror Media Group

  • White Papers // Apr 2012

    Hardness Results for Static Priority Real-Time Scheduling

    Real-time systems are often modeled as a collection of tasks, describing the structure of the processor's workload. In the literature, task-models of different expressiveness have been developed, ranging from the traditional periodic task model to highly expressive graph-based models. For dynamic priority schedulers, it has been shown that the schedulability...

    Provided By Uppror Media Group

  • White Papers // Mar 2012

    A Ubiquitous Publish/Subscribe Platform for Wireless Sensor Networks with Mobile Mules

    Existing publish/subscribe architectures for wireless sensors networks only support stationary sensors interconnected with each other. They cannot handle mobile sensors or remote sensors that are sparsely deployed. In this paper, the authors propose a novel ubiquitous publish/subscribe system that supports data access from both mobile sensors and stationary sensors. Their...

    Provided By Uppror Media Group

  • White Papers // Mar 2012

    An Optimisation-Based Approach for Wireless Sensor Deployment in Mobile Sensing Environments

    The authors consider a novel application in wireless sensor networks where mobile phones and wireless sensors can collaborate to collect sensing data. Although mobile phones can perform sensing at different locations, it is a challenge to provide stable sensing quality and availability over the entire area. One approach is to...

    Provided By Uppror Media Group

  • White Papers // Mar 2012

    A Location-Based Publish/Subscribe Framework for Wireless Sensors and Mobile Phones

    Wireless Sensor Networks (WSNs) have been widely deployed for environmental monitoring and urban sensing applications. With the advancement of mobile phones, mobile users have increasing demands for sensing data relevant to their locations and activities. It is crucial to support reliable ubiquitous sensing for mobile users to retrieve sensing data...

    Provided By Uppror Media Group

  • White Papers // Jan 2012

    Counter-Example Guided Fence Insertion under TSO

    The authors give a sound and complete fence insertion procedure for concurrent finite-state programs running under the classical TSO memory model. This model allows \"Write to read\" relaxation corresponding to the addition of an unbounded store buffer between each processor and the main memory. They introduce a novel machine model,...

    Provided By Uppror Media Group

  • White Papers // Jan 2012

    B-IFDMA - A Power Efficient Multiple Access Scheme for Non-Frequency-Adaptive Transmission

    Within the EU FP6 Integrated Projects WINNER and WINNER II, multiple access schemes for frequency-adaptive and non-frequency-adaptive transmission for a future broadband mobile wireless system are investigated. This paper presents a novel power efficient multiple access scheme for non-frequency-adaptive uplink transmission denoted Block Interleaved Frequency Division Multiple Access (B-IFDMA), which...

    Provided By Uppror Media Group

  • White Papers // Oct 2011

    On Kalman Filtering With Fading Wireless Channels Governed by Power Control

    The authors study stochastic stability for Kalman filtering over fading wireless channels where variable channel gains are counteracted by the use of power control to alleviate the effects of packet drops. The Kalman filter and the controller are located at a single gateway which acquires data from the wireless sensors....

    Provided By Uppror Media Group

  • White Papers // Sep 2011

    Effective and Efficient Scheduling of Certifiable Mixed-Criticality Sporadic Task Systems

    An increasing trend in embedded system design is to integrate components with different levels of criticality into a shared hardware platform for better cost and power efficiency. Such mixed-criticality systems are subject to certifications at different levels of rigorousness, for validating the correctness of different subsystems on various confidence levels....

    Provided By Uppror Media Group

  • White Papers // May 2011

    Mobile Sources in an Information-Centric Network with Hierarchical Names: An Indirection Approach

    An increasing amount of information is available from mobile devices. The authors consider the problem of retrieving data from mobile sources in an information-centric network architecture called Named Data Networking. They propose an approach in which indirection points locally map requests for persistent data names to requests for temporary location...

    Provided By Uppror Media Group

  • White Papers // Apr 2011

    Resource Sharing Protocols for Real-Time Task Graph Systems

    Previous papers on real-time task graph models have ignored the crucial resource sharing problem. Due to the non-deterministic branching behavior, resource sharing in graph-based task models is significantly more difficult than in the simple periodic or sporadic task models. In this paper, the authors address this problem with several different...

    Provided By Uppror Media Group

  • White Papers // Apr 2011

    On the Tractability of Digraph-Based Task Models

    In formal analysis of real-time systems, a major concern is the analysis efficiency. As the expressiveness of models grows, so grows the complexity of their analysis. A recently proposed model, the Digraph Real-time Task model (DRT), offers high expressiveness well beyond traditional periodic task models. Still, the associated feasibility problem...

    Provided By Uppror Media Group

  • White Papers // Apr 2011

    Evaluation and Enhancement of TCP With Network Coding in Wireless Multihop Networks

    In this paper, the authors, based on NS-2 simulator, evaluate the performances of different TCP protocols with network coding in wireless multihop networks, and then propose two schemes to enhance the performances of TCPs with network coding. In particular the network coding scheme considered and used here is COPE, which...

    Provided By Uppror Media Group

  • White Papers // Mar 2011

    Stability of State Estimation Over Sensor Networks With Markovian Fading Channels

    Stochastic stability for centralized Kalman filtering over a wireless sensor network with correlated fading channels is studied. On their route to the gateway, sensor packets, possibly aggregated with measurements from several nodes, may be dropped because of fading links. By assuming the network states to be Markovian, the authors establish...

    Provided By Uppror Media Group

  • White Papers // Mar 2011

    Implementation and Empirical Comparison of Partitioning-based Multi-core Scheduling

    Recent theoretical studies have shown that partitioning-based scheduling has better real-time performance than other scheduling paradigms like global scheduling on multi-cores. Especially, a class of partitioning-based scheduling algorithms (called semi-partitioned scheduling), which allow to split a small number of tasks among different cores, offer very high resource utilization. The major...

    Provided By Uppror Media Group

  • White Papers // Jan 2011

    The Digraph Real-Time Task Model

    Models for real-time systems have to balance the inherently contradicting goals of expressiveness and analysis efficiency. Current, task models with tractable feasibility tests have limited expressiveness, restricting their ability to model many systems accurately. In particular, they are all recurrent, preventing the modeling of structures like mode switches, local loops,...

    Provided By Uppror Media Group

  • White Papers // Oct 2010

    Fixed-Priority Multiprocessor Scheduling: Beyond Liu & Layland Utilization Bound

    The increasing interests in multicore raise the question whether utilization bounds for uniprocessor scheduling can be generalized to the multiprocessor setting. Recently, this has been shown for the famous Liu and Layland utilization bound by applying novel task splitting techniques. However, parametric utilization bounds that can guarantee higher utilizations (up...

    Provided By Uppror Media Group

  • White Papers // Jul 2010

    Utility of Joint Processing Schemes

    Joint processing between base stations has been shown as an efficient technique to mitigate inter-cell interference and increase data rates, in particular at the cell edges. In this paper, the authors evaluate the utility of Internet applications in a joint processing enabled cluster of base stations. Utility is used to...

    Provided By Uppror Media Group

  • White Papers // Jun 2010

    Flow Augmenting Routing With Network Coding for Lifetime Maximization in Wireless Networks

    The life-time maximization routing with network coding in wireless multihop networks is considered in this paper. The problems are formulated in three different cases: no network coding, two-way network coding, and overhearing network coding. Flow Augmenting routing (FA) is used to solve the first case, and then it is extended...

    Provided By Uppror Media Group

  • White Papers // Jun 2010

    Dynamic Load Balancing in 3GPP LTE Multi-Cell Networks With Heterogeneous Services

    Load balancing among multi-cells in 3GPP Long Term Evolution (LTE) networks with heterogeneous services is investigated. It is formulated as a multi-objective optimization problem, the objectives of which are load balancing index of services with QoS requirements and network utility of other services. The constraints are physical resource limits and...

    Provided By Uppror Media Group

  • White Papers // May 2010

    Combining Abstract Interpretation with Model Checking for Timing Analysis of Multicore Software

    It is predicted that multicore will be increasingly used in future embedded real-time systems for high performance and low energy consumption. The major obstacle is that the authors may not predict and provide any guarantee on real-time properties of software on such platforms. The shared memory bus is among the...

    Provided By Uppror Media Group

  • White Papers // Apr 2010

    Minimizing Multi-Resource Energy for Real-Time Systems with Discrete Operation Modes

    Energy conservation is an important issue in the design of embedded systems. Dynamic Voltage Scaling (DVS) and Dynamic Power Management (DPM) are two widely used techniques for saving energy in such systems. In this paper, the authors address the problem of minimizing multi-resource energy consumption concerning both CPU and devices....

    Provided By Uppror Media Group

  • White Papers // Mar 2010

    Cross-Layer Optimization of Wireless Multi-Hop Networks with Network Coding

    In this paper, the authors present a cross-layer algorithm for joint optimization of congestion control, routing, and scheduling in wireless multi-hop networks with network coding. They introduce virtual flow variables in the formulation of capacity region of the networks. The utility maximization problem subject to constraints on the capacity region...

    Provided By Uppror Media Group

  • White Papers // Dec 2009

    Constrained Optimisation Over Massive Databases

    Constrained optimisation is increasingly considered by industry as a major candidate to cope with hard problems of practical relevance. However, the approach of exploiting, in those scenarios, current constraint or mathematical programming solvers has severe limitations, which clearly demand new methods: data is usually stored in potentially very-large databases, and...

    Provided By Uppror Media Group

  • White Papers // Jul 2009

    Cost Design for Cross-Layer Resource Allocation in Cognitive Radio Ad Hoc Networks

    In this paper, cost function for routing is studied. By introduction of improved cost function, an improved algorithm is proposed. Compared with the original algorithm, the improved algorithm is more stable and the feasible solution obtained is closer to the upper bound of optimal solution. The optimal solution lies between...

    Provided By Uppror Media Group

  • White Papers // May 2009

    New Response Time Bounds for Fixed Priority Multiprocessor Scheduling

    Recently, there have been several promising techniques developed for schedulability analysis and response time analysis for multiprocessor systems based on over-approximation. This paper contains two contributions. First, to improve the analysis precision, the authors apply Baruah's window analysis framework to response time analysis for sporadic tasks on multiprocessor systems where...

    Provided By Uppror Media Group

  • White Papers // Nov 2008

    Innovations-Based State Estimation With Wireless Sensor Networks

    The authors study a state estimation architecture for sensor networks, where several sensors transmit quantized innovations to a central estimator. Transmission is via a wireless channel, which is prone to fading leading to random packet loss. State estimation is carried out at the gateway via a time-varying Kalman filter which...

    Provided By Uppror Media Group

  • White Papers // Jul 2008

    Improving Scalability of Model-Checking for Minimizing Buffer Requirements of Synchronous Dataflow Graphs

    Synchronous DataFlow (SDF) is a well-known model of computation for dataflow-oriented applications such as signal processing and multimedia. It is important to minimize the buffer size requirements of the source code generated from a given SDF model, since memory space is often a scarce resource for these applications due to...

    Provided By Uppror Media Group

  • White Papers // May 2008

    New Schedulability Test Conditions for Non-preemptive Scheduling on Multiprocessor Platforms

    The authors study the schedulability analysis problem for non-preemptive scheduling algorithms on multiprocessors. To their best knowledge, the only known work on this problem is the test condition proposed by the researcher for non-preemptive EDF scheduling, which will reject a task set with arbitrarily low utilization if it contains a...

    Provided By Uppror Media Group

  • White Papers // Mar 2012

    A Ubiquitous Publish/Subscribe Platform for Wireless Sensor Networks with Mobile Mules

    Existing publish/subscribe architectures for wireless sensors networks only support stationary sensors interconnected with each other. They cannot handle mobile sensors or remote sensors that are sparsely deployed. In this paper, the authors propose a novel ubiquitous publish/subscribe system that supports data access from both mobile sensors and stationary sensors. Their...

    Provided By Uppror Media Group

  • White Papers // May 2011

    Mobile Sources in an Information-Centric Network with Hierarchical Names: An Indirection Approach

    An increasing amount of information is available from mobile devices. The authors consider the problem of retrieving data from mobile sources in an information-centric network architecture called Named Data Networking. They propose an approach in which indirection points locally map requests for persistent data names to requests for temporary location...

    Provided By Uppror Media Group

  • White Papers // Apr 2013

    Electronically-Switched Directional Antennas for Wireless Sensor Networks: A Full-Stack Evaluation

    The authors study the benefits of Electronically-Switched Directional (ESD) antennas in Wireless Sensor Networks (WSNs). ESD antennas have proved beneficial in cellular and ad-hoc networks, by increasing the communication range and by alleviating contention in directions other than the destination. The advantages in WSNs are, however, still largely to be...

    Provided By Uppror Media Group

  • White Papers // Dec 2012

    Understanding Link Dynamics in Wireless Sensor Networks With Dynamically Steerable Directional Antennas

    By radiating the power in the direction of choice, Electronically Switched Directional (ESD) antennas can reduce network contention and avoid packet loss. There exists some ESD antennas for wireless sensor networks, but so far researchers have mainly evaluated their directionality. There are no studies regarding the link dynamics of ESD...

    Provided By Uppror Media Group

  • White Papers // Dec 2009

    Constrained Optimisation Over Massive Databases

    Constrained optimisation is increasingly considered by industry as a major candidate to cope with hard problems of practical relevance. However, the approach of exploiting, in those scenarios, current constraint or mathematical programming solvers has severe limitations, which clearly demand new methods: data is usually stored in potentially very-large databases, and...

    Provided By Uppror Media Group

  • White Papers // May 2009

    New Response Time Bounds for Fixed Priority Multiprocessor Scheduling

    Recently, there have been several promising techniques developed for schedulability analysis and response time analysis for multiprocessor systems based on over-approximation. This paper contains two contributions. First, to improve the analysis precision, the authors apply Baruah's window analysis framework to response time analysis for sporadic tasks on multiprocessor systems where...

    Provided By Uppror Media Group

  • White Papers // Jan 2012

    Counter-Example Guided Fence Insertion under TSO

    The authors give a sound and complete fence insertion procedure for concurrent finite-state programs running under the classical TSO memory model. This model allows \"Write to read\" relaxation corresponding to the addition of an unbounded store buffer between each processor and the main memory. They introduce a novel machine model,...

    Provided By Uppror Media Group

  • White Papers // Jan 2013

    An Integrated Specification and Verification Technique for Highly Concurrent Data Structures

    The authors present a technique for automatically verifying safety properties of concurrent programs, in particular programs which rely on subtle dependencies of local states of different threads, such as lock-free implementations of stacks and queues in an environment without garbage collection. Their technique addresses the joint challenges of infinite-state specifications,...

    Provided By Uppror Media Group

  • White Papers // Apr 2012

    Bounding and Shaping the Demand of Mixed-Criticality Sporadic Tasks

    The authors derive demand-bound functions for mixed-criticality sporadic tasks, and use these to determine EDF-schedulability. Tasks have different demand-bound functions for each criticality mode. They show how to shift execution demand from high-to low-criticality mode by tuning the relative deadlines. This paper allows the user to shape the demand characteristics...

    Provided By Uppror Media Group

  • White Papers // Apr 2012

    Hardness Results for Static Priority Real-Time Scheduling

    Real-time systems are often modeled as a collection of tasks, describing the structure of the processor's workload. In the literature, task-models of different expressiveness have been developed, ranging from the traditional periodic task model to highly expressive graph-based models. For dynamic priority schedulers, it has been shown that the schedulability...

    Provided By Uppror Media Group

  • White Papers // Apr 2011

    On the Tractability of Digraph-Based Task Models

    In formal analysis of real-time systems, a major concern is the analysis efficiency. As the expressiveness of models grows, so grows the complexity of their analysis. A recently proposed model, the Digraph Real-time Task model (DRT), offers high expressiveness well beyond traditional periodic task models. Still, the associated feasibility problem...

    Provided By Uppror Media Group

  • White Papers // Apr 2011

    Resource Sharing Protocols for Real-Time Task Graph Systems

    Previous papers on real-time task graph models have ignored the crucial resource sharing problem. Due to the non-deterministic branching behavior, resource sharing in graph-based task models is significantly more difficult than in the simple periodic or sporadic task models. In this paper, the authors address this problem with several different...

    Provided By Uppror Media Group

  • White Papers // Jan 2011

    The Digraph Real-Time Task Model

    Models for real-time systems have to balance the inherently contradicting goals of expressiveness and analysis efficiency. Current, task models with tractable feasibility tests have limited expressiveness, restricting their ability to model many systems accurately. In particular, they are all recurrent, preventing the modeling of structures like mode switches, local loops,...

    Provided By Uppror Media Group

  • White Papers // Oct 2010

    Fixed-Priority Multiprocessor Scheduling: Beyond Liu & Layland Utilization Bound

    The increasing interests in multicore raise the question whether utilization bounds for uniprocessor scheduling can be generalized to the multiprocessor setting. Recently, this has been shown for the famous Liu and Layland utilization bound by applying novel task splitting techniques. However, parametric utilization bounds that can guarantee higher utilizations (up...

    Provided By Uppror Media Group

  • White Papers // May 2008

    New Schedulability Test Conditions for Non-preemptive Scheduling on Multiprocessor Platforms

    The authors study the schedulability analysis problem for non-preemptive scheduling algorithms on multiprocessors. To their best knowledge, the only known work on this problem is the test condition proposed by the researcher for non-preemptive EDF scheduling, which will reject a task set with arbitrarily low utilization if it contains a...

    Provided By Uppror Media Group

  • White Papers // Apr 2008

    Cyclic Dependencies in Modular Performance Analysis

    In the analysis of component-based real-time systems, common questions are whether a particular workload can be processed in time on a given architecture, or whether a task set is schedulable given a certain availability of resources. An abstraction for modeling and analyzing such problems is the Modular Performance Analysis based...

    Provided By Uppror Media Group

  • White Papers // Jul 2012

    Monotonic Abstraction for Programs with Multiply-Linked Structures

    The authors investigate the use of monotonic abstraction and back-ward reachability analysis as means of performing shape analysis on programs with multiply pointed structures. By encoding the heap as a vertex- and edge-labeled graph, they can model the low level behavior exhibited by programs written in the C programming language....

    Provided By Uppror Media Group

  • White Papers // Nov 2013

    Verification of Heap Manipulating Programs with Ordered Data by Extended Forest Automata

    The authors present a general framework for verifying programs with complex dynamic linked data structures whose correctness depends on ordering relations between stored data values. The underlying formalism of their framework is that of Forest Automata (FA), which has previously been developed for verification of heap-manipulating programs. They extend FA...

    Provided By Uppror Media Group

  • White Papers // Jun 2010

    Flow Augmenting Routing With Network Coding for Lifetime Maximization in Wireless Networks

    The life-time maximization routing with network coding in wireless multihop networks is considered in this paper. The problems are formulated in three different cases: no network coding, two-way network coding, and overhearing network coding. Flow Augmenting routing (FA) is used to solve the first case, and then it is extended...

    Provided By Uppror Media Group

  • White Papers // Mar 2011

    Stability of State Estimation Over Sensor Networks With Markovian Fading Channels

    Stochastic stability for centralized Kalman filtering over a wireless sensor network with correlated fading channels is studied. On their route to the gateway, sensor packets, possibly aggregated with measurements from several nodes, may be dropped because of fading links. By assuming the network states to be Markovian, the authors establish...

    Provided By Uppror Media Group

  • White Papers // Oct 2011

    On Kalman Filtering With Fading Wireless Channels Governed by Power Control

    The authors study stochastic stability for Kalman filtering over fading wireless channels where variable channel gains are counteracted by the use of power control to alleviate the effects of packet drops. The Kalman filter and the controller are located at a single gateway which acquires data from the wireless sensors....

    Provided By Uppror Media Group

  • White Papers // Apr 2011

    Evaluation and Enhancement of TCP With Network Coding in Wireless Multihop Networks

    In this paper, the authors, based on NS-2 simulator, evaluate the performances of different TCP protocols with network coding in wireless multihop networks, and then propose two schemes to enhance the performances of TCPs with network coding. In particular the network coding scheme considered and used here is COPE, which...

    Provided By Uppror Media Group

  • White Papers // Jun 2010

    Dynamic Load Balancing in 3GPP LTE Multi-Cell Networks With Heterogeneous Services

    Load balancing among multi-cells in 3GPP Long Term Evolution (LTE) networks with heterogeneous services is investigated. It is formulated as a multi-objective optimization problem, the objectives of which are load balancing index of services with QoS requirements and network utility of other services. The constraints are physical resource limits and...

    Provided By Uppror Media Group

  • White Papers // Jul 2010

    Utility of Joint Processing Schemes

    Joint processing between base stations has been shown as an efficient technique to mitigate inter-cell interference and increase data rates, in particular at the cell edges. In this paper, the authors evaluate the utility of Internet applications in a joint processing enabled cluster of base stations. Utility is used to...

    Provided By Uppror Media Group

  • White Papers // Jul 2009

    Cost Design for Cross-Layer Resource Allocation in Cognitive Radio Ad Hoc Networks

    In this paper, cost function for routing is studied. By introduction of improved cost function, an improved algorithm is proposed. Compared with the original algorithm, the improved algorithm is more stable and the feasible solution obtained is closer to the upper bound of optimal solution. The optimal solution lies between...

    Provided By Uppror Media Group

  • White Papers // Mar 2010

    Cross-Layer Optimization of Wireless Multi-Hop Networks with Network Coding

    In this paper, the authors present a cross-layer algorithm for joint optimization of congestion control, routing, and scheduling in wireless multi-hop networks with network coding. They introduce virtual flow variables in the formulation of capacity region of the networks. The utility maximization problem subject to constraints on the capacity region...

    Provided By Uppror Media Group

  • White Papers // Nov 2008

    Innovations-Based State Estimation With Wireless Sensor Networks

    The authors study a state estimation architecture for sensor networks, where several sensors transmit quantized innovations to a central estimator. Transmission is via a wireless channel, which is prone to fading leading to random packet loss. State estimation is carried out at the gateway via a time-varying Kalman filter which...

    Provided By Uppror Media Group

  • White Papers // Jan 2012

    B-IFDMA - A Power Efficient Multiple Access Scheme for Non-Frequency-Adaptive Transmission

    Within the EU FP6 Integrated Projects WINNER and WINNER II, multiple access schemes for frequency-adaptive and non-frequency-adaptive transmission for a future broadband mobile wireless system are investigated. This paper presents a novel power efficient multiple access scheme for non-frequency-adaptive uplink transmission denoted Block Interleaved Frequency Division Multiple Access (B-IFDMA), which...

    Provided By Uppror Media Group

  • White Papers // May 2012

    Measurement-Based Evaluation of Robust Linear Precoding for Downlink CoMP

    The authors study the design and evaluation of joint processing Coordinated Multi-Point (CoMP) downlink transmission. Precoders will then be designed based on outdated Channel State Information (CSI), so interference cannot be eliminated completely as by an ideal Zero-Forcing (ZF) solution. They here strive to design and evaluate realistic linear transmit...

    Provided By Uppror Media Group

  • White Papers // May 2012

    Avoiding Overages by Deferred Aggregate Demand for PEV Charging on the Smart Grid

    The authors model the aggregate overnight demand for electricity by a large community of (possibly hybrid) Plug-in Electric Vehicles (PEVs) each of whose power demand follows a prescribed profile and is interruptible. Rather than a spot-price system for household consumers (which would necessarily need to be operated by automated means...

    Provided By Uppror Media Group

  • White Papers // Mar 2012

    An Optimisation-Based Approach for Wireless Sensor Deployment in Mobile Sensing Environments

    The authors consider a novel application in wireless sensor networks where mobile phones and wireless sensors can collaborate to collect sensing data. Although mobile phones can perform sensing at different locations, it is a challenge to provide stable sensing quality and availability over the entire area. One approach is to...

    Provided By Uppror Media Group

  • White Papers // Mar 2012

    A Location-Based Publish/Subscribe Framework for Wireless Sensors and Mobile Phones

    Wireless Sensor Networks (WSNs) have been widely deployed for environmental monitoring and urban sensing applications. With the advancement of mobile phones, mobile users have increasing demands for sensing data relevant to their locations and activities. It is crucial to support reliable ubiquitous sensing for mobile users to retrieve sensing data...

    Provided By Uppror Media Group

  • White Papers // Jul 2013

    Skew Handling in Aggregate Streaming Queries on GPUs

    Now-a-days, the data to be processed by database systems has grown so large that any conventional, centralized technique is inadequate. At the same time, General Purpose computation on GPU (GPGPU) recently has successfully drawn attention from the data management community due to its ability to achieve significant speed-ups at a...

    Provided By Uppror Media Group

  • White Papers // Apr 2007

    Cost-Based Optimization of Complex Scientific Queries

    High energy physics scientists analyze large amounts of data looking for interesting events when particles collide. These analyses are easily expressed using complex queries that filter events. The authors developed a cost model for aggregation operators and other functions used in such queries and show that it substantially improves performance....

    Provided By Uppror Media Group

  • White Papers // Sep 2013

    General and Efficient Response Time Analysis for EDF Scheduling

    Response Time Analysis (RTA) is one of the key problems in real-time system design. This paper proposes new RTA methods for EDF scheduling, with general system models where workload and resource availability are represented by request/demand bound functions and supply bound functions. The main idea is to derive response time...

    Provided By Uppror Media Group

  • White Papers // Sep 2013

    Combinatorial Abstraction Refinement for Feasibility Analysis

    The traditional periodic workload model for hard real-time systems has been extended by more expressive models in recent years. These models based on different classes of directed graphs allow modeling of structures like frames, branching and loops. With more expressiveness comes higher complexity of the associated analysis problems. Feasibility of...

    Provided By Uppror Media Group

  • White Papers // Sep 2011

    Effective and Efficient Scheduling of Certifiable Mixed-Criticality Sporadic Task Systems

    An increasing trend in embedded system design is to integrate components with different levels of criticality into a shared hardware platform for better cost and power efficiency. Such mixed-criticality systems are subject to certifications at different levels of rigorousness, for validating the correctness of different subsystems on various confidence levels....

    Provided By Uppror Media Group

  • White Papers // Mar 2011

    Implementation and Empirical Comparison of Partitioning-based Multi-core Scheduling

    Recent theoretical studies have shown that partitioning-based scheduling has better real-time performance than other scheduling paradigms like global scheduling on multi-cores. Especially, a class of partitioning-based scheduling algorithms (called semi-partitioned scheduling), which allow to split a small number of tasks among different cores, offer very high resource utilization. The major...

    Provided By Uppror Media Group

  • White Papers // May 2010

    Combining Abstract Interpretation with Model Checking for Timing Analysis of Multicore Software

    It is predicted that multicore will be increasingly used in future embedded real-time systems for high performance and low energy consumption. The major obstacle is that the authors may not predict and provide any guarantee on real-time properties of software on such platforms. The shared memory bus is among the...

    Provided By Uppror Media Group

  • White Papers // Apr 2010

    Minimizing Multi-Resource Energy for Real-Time Systems with Discrete Operation Modes

    Energy conservation is an important issue in the design of embedded systems. Dynamic Voltage Scaling (DVS) and Dynamic Power Management (DPM) are two widely used techniques for saving energy in such systems. In this paper, the authors address the problem of minimizing multi-resource energy consumption concerning both CPU and devices....

    Provided By Uppror Media Group