Ecole Polytechnique Federale de Lausanne

Displaying 1-40 of 73 results

  • White Papers // Apr 2014

    A Computationally Efficient Limited Memory CMA-ES for Large Scale Optimization

    The authors propose a computationally efficient Limited Memory Co-variance Matrix Adaptation Evolution Strategy for large scale optimization, which they call the LM-CMA-ES. The LM-CMA-ES is a stochastic, derivative-free algorithm for numerical optimization of non-linear, non-convex optimization problems in continuous domain. Inspired by the limited memory BFGS method, the LM- CMA-ES...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2013

    Solving Shortest and Closest Vector Problems: The Decomposition Approach

    In this paper, the authors present a heuristic algorithm for solving exact, as well as approximate, SVP and CVP for lattices. This algorithm is based on a new approach which is very different from and complementary to the sieving technique. This new approach frees them from the kissing number bound...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Aug 2013

    Improving Flash Write Performance by Using Update Frequency

    Solid-State Drives (SSDs) are quickly becoming the de-fault storage medium as the cost of NAND ash memory continues to drop. However, ash memory introduces new challenges, as data cannot be efficiently updated in-place. To overcome the technology's limitations, SSDs incorporate a software Flash Translation Layer (FTL) that implements out-of-place updates,...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2013

    Practical & Provably Secure Distance-Bounding

    Distance-bounding is a practical solution to be used in security-sensitive contexts, to prevent relay attacks. Its applied cryptographic role is definitely spreading fast and it is clearly far reaching, extending from contactless payments to remote car unlocking. However, security models for distance-bounding are not well-established and, as far as the...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2013

    Task Scheduling for Highly Concurrent Analytical and Transactional Main-Memory Workloads

    Task scheduling typically employs a worker thread per hardware context to process a dynamically changing set of tasks. It is an appealing solution to exploit modern multi-core processors, as it eases parallelization and avoids unnecessary context switches and their associated costs. Naively bundling DBMS operations into tasks, however, can result...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2013

    A Prototype Implementation for the IntServ Operation Over DiffServ Networks

    Combining Integrated Services QoS mechanisms for end-to-end signaling at hosts and Differentiated Services QoS mechanisms in the network core is one proposal for overcoming the limitation of either mechanism when applied alone. In this paper, some of the open issues are discussed and a concrete proposal is presented, which maps...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2012

    CoRD: A Collaborative Framework for Distributed Data Race Detection

    Modern concurrent software is riddled with data races and these races constitute the source of many problems. Data races are hard to detect accurately before software is shipped and, once they cause failures in production, developers find it challenging to reproduce and debug them. Ideally, all data races should be...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2012

    Several Weak Bit-Commitments Using Seal-Once Tamper-Evident Devices

    Following both theoretical and practical arguments, the authors construct UC-secure bit-commitment protocols that place their strength on the sender's side and are built using tamper-evident devices, e.g., a type of distinguishable, sealed envelopes. They show that by using a second formalization of tamper-evident distinguishable envelopes they can attain better security...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2012

    Model Checking Duration Calculus: A Practical Approach

    Model checking of real-time systems with respect to Duration Calculus (DC) specifications requires the translation of DC formulae into automata-based semantics. This task is difficult to automate. The existing algorithms provide a limited DC coverage and do not support compositional verification. The authors propose a translation algorithm that advances the...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Dec 2011

    Same Queries, Different Data: Can we Predict Runtime Performance?

    The authors consider MapReduce workloads that are produced by analytics applications. In contrast to ad hoc query workloads, analytics applications are comprised of fixed data flows that are run over newly arriving data sets or on different portions of an existing data set. Examples of such workloads include document analysis/indexing,...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Dec 2011

    Distributed Rate Allocation in P2P Networks with Inter-Session Network Coding

    In this paper, the authors propose a distributed rate allocation algorithm for delay minimal data delivery in overlay networks where multiple sources compete simultaneously for the available network resources. In order to efficiently utilize the network resources, they propose to use inter-session network coding. They devise a distributed algorithm that...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2011

    Distributed Sensor Failure Detection in Sensor Networks

    The authors investigate distributed sensors' failure detection in networks with a small number of defective sensors. They assume that sensors measure a smooth physical phenomenon and that defective sensors' measurements significantly differ from neighboring sensor measurements. They consider that the defective sensors are well represented by binary sparse signals. Sensor...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2011

    Network Coding for Undirected Information Exchange

    The authors consider the information exchange problem where each in a set of terminals transmits information to all other terminals in the set, over an undirected network. They show that the design of only a single network code for multicasting is sufficient to achieve an arbitrary point in the achievable...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2011

    Impact of Vehicular Communication Security on Transportation Safety

    Transportation safety, one of the main driving forces of the development of Vehicular Communication (VC) systems, relies on high-rate safety messaging (beaconing). At the same time, there is consensus among authorities, industry, and academia on the need to secure VC systems. With specific proposals in the literature, a critical question...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2011

    Privacy and Identity Management for Vehicular Communication Systems: A Position Paper

    The emerging technology of Vehicular Communications (VC) raises a number of technical problems that need to be addressed. Among those, security and privacy concerns are paramount for the wide adoption of VC. In this position paper, the authors are concerned with privacy and identity management in the context of these...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2011

    On the Road: Reflections on the Security of Vehicular Communication Systems

    Vehicular Communication (VC) systems have recently drawn the attention of industry, authorities, and academia. A consensus on the need to secure VC systems and protect the privacy of their users led to concerted efforts to design security architectures. Interestingly, the results different project contributed thus far bear extensive similarities in...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2011

    Architecture for Secure and Private Vehicular Communications

    The deployment of Vehicular Communication (VC) systems is strongly dependent on their security and privacy features. In this paper, the authors propose a security architecture for VC. The primary objectives of the architecture include the management of identities and cryptographic keys, the security of communications, and the integration of privacy...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jun 2011

    Cache-Aware Lock-Free Concurrent Hash Tries

    This paper describes an implementation of a non-blocking concurrent shared-memory hash trie based on single-word compare-and-swap instructions. Insert, lookup and remove operations modifying different parts of the hash trie can be run independent of each other and do not contend. Remove operations ensure that the unneeded memory is freed and...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // May 2011

    Chebyshev Polynomial Approximation for Distributed Signal Processing

    Unions of graph Fourier multipliers are an important class of linear operators for processing signals defined on graphs. The authors present a novel method to efficiently distribute the application of these operators to the high-dimensional signals collected by sensor networks. The proposed method features approximations of the graph Fourier multipliers...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Mar 2011

    Are Sparse Representations Really Relevant for Image Classification?

    Recent years have seen an increasing interest in sparse representations for image classification and object recognition, probably motivated by evidence from the analysis of the primate visual cortex. It is still unclear, however, whether or not sparsity helps classification. In this paper, the authors evaluate its impact on the recognition...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Feb 2011

    Autonomic SLA-Driven Provisioning for Cloud Applications

    Significant achievements have been made for automated allocation of cloud resources. However, the performance of applications may be poor in peak load periods, unless their cloud resources are dynamically adjusted. Moreover, although cloud resources dedicated to different applications are virtually isolated, performance fluctuations do occur because of resource sharing, and...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    A Real-Time Compressed Sensing-Based Personal Electrocardiogram Monitoring System

    Wireless Body Sensor Networks (WBSN) hold the promise to enable next-generation patient-centric mobile-cardiology systems. A WBSN-enabled ElectroCardioGram (ECG) monitor consists of wearable, miniaturized and wireless sensors able to measure and wirelessly report cardiac signals to a WBSN coordinator, which is responsible for reporting them to the tele-health provider. However, state-of-the-art...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Performance Profiling of Virtual Machines

    Profilers based on hardware performance counters are indispensable for performance debugging of complex software systems. All modern processors feature hardware performance counters, but current Virtual Machine Monitors (VMMs) do not properly expose them to the guest operating systems. Existing profiling tools require privileged access to the VMM to profile the...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Multi-Radio Diversity in Wireless Networks

    This paper describes the Multi-Radio Diversity (MRD) wireless system, which uses path diversity to improve loss resilience in Wireless Local Area Networks (WLANs). MRD coordinates wireless receptions among multiple radios to improve loss resilience in the face of path-dependent frame corruption over the radio. MRD incorporates two techniques to recover...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Analysis of Supportable Rates in Symmetric Blocking Wavelength Routers

    Constructing an n ? n non-blocking wavelength router using n ? n optical cross-connects may be impractical due to certain constraints such as the cost or space limitations. Moreover, in many cases the traffic requirements can be handled without a non-blocking router. In this paper, the authors study blocking wavelength...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Indexing Data-Oriented Overlay Networks

    The application of structured overlay networks to implement index structures for data-oriented applications such as peer-to-peer databases or peer-to-peer information retrieval, requires highly efficient approaches for overlay construction, as changing application requirements frequently lead to re-indexing of the data and hence (re-)construction of overlay networks. This problem has so far...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Online Broadcasting With Network Coding

    Consider a source broadcasting M packets to N receivers over independent erasure channels, where perfect feedback is available from the receivers to the source, and the source is allowed to use coding. The authors investigate offline and online algorithms that optimize delay, both through theoretical analysis as well as simulation...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Survivable Mapping Algorithm by Ring Trimming (SMART) for Large IP-Over-WDM Networks

    The authors develop a fast and efficient algorithm that finds a survivable (i.e., robust to single fiber failures) mapping of IP topology on the mesh of fibers in IP-over-WDM networks; they call it SMART. A number of algorithms solving this problem can be found in the literature. Since ILP solutions...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    On Survivable Routing of Mesh Topologies in IP-Over-WDM Networks

    Generally, there are two approaches for providing survivability of IP-over-WDM networks: protection and restoration. Protection uses pre-computed backup paths applied in the case of a failure. Restoration finds dynamically a new path, once a failure has occurred. Protection is less resource efficient (the resources are committed without prior knowledge of...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Local Binary Patterns as an Image Preprocessing for Face Authentication

    One of the major problems in face authentication systems is to deal with variations in illumination. In a realistic scenario, it is very likely that the lighting condition of the probe image does not correspond to those of the gallery image, hence there is a need to handle such variations....

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Robust Routing for Dynamic Wireless Networks Based on Stable Embeddings

    Routing packets is a central function of multi-hop wireless networks. Traditionally, there have been two paradigms for routing, either based on the geographical coordinates of the nodes (geographic routing), or based on the connectivity graph (topology-based routing). The former implicitly assumes that geometry determines connectivity, whereas the latter does not...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Dec 2010

    TPC-E vs. TPC-C: Characterizing the New TPC-E Benchmark via an I/O Comparison Study

    TPC-E is a new OLTP benchmark recently approved by the Transaction Processing Performance Council (TPC). In this paper, the authors compare TPC-E with the familiar TPCC benchmark in order to understand the behavior of the new TPC-E benchmark. In particular, they compare the I/O access patterns of the two benchmarks...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Dec 2010

    Flash in a DBMS: Where and How?

    For the past 40 years, Hard Disk Drives (HDDs) have been the building blocks of storage systems. The mechanics of HDDs rotating platters dictate their performance limitations: latencies dominated by mechanical delays (seeks and rotational latencies), throughputs for random accesses much lower than sequential accesses, interference between multiple concurrent workloads...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Nov 2010

    Improving OLTP concurrency through Early Lock Release

    Since the beginning of the multi-core era, database systems research has restarted focusing on increasing concurrency. Even though database systems have been able to accommodate concurrent requests, the exploding number of available cores per chip has surfaced new difficulties. More and more transactions can be served in parallel (since more...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2010

    The Improbable Differential Attack: Cryptanalysis of Reduced Round CLEFIA

    In this paper the authors present a new statistical cryptanalytic technique that they call improbable differential cryptanalysis which uses a differential that is less probable when the correct key is used. The authors provide data complexity estimates for this kind of attacks and they also show a method to expand...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2010

    Tracking of Mobile Devices Through Bluetooth Contacts

    The authors investigate if it is possible to reconstruct a mobile phone's mobility using its Bluetooth contacts with other mobile devices, some of which are equipped with GPS receivers. The data mining analysis, based on two different data sets, shows that in certain environments coarse grained mobility of a significant...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2010

    Improving API Documentation for Java-Like Languages

    The Javadoc paradigm for displaying API documentation to users is quite popular, with similar variants existing for many mainstream languages. However, two user interface design properties of Javadoc may reduce its utility when displaying documentation for APIs that make use of inheritance and parametric polymorphism. First, Javadoc does not show...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2010

    Thermal-Aware Compilation for Register Window-Based Embedded Processors

    The development of compiler-based mechanisms to optimize the thermal profile of large register files to improve the processor reliability has become an important issue. Thermal hotspots have been known to cause severe reliability issues, while the thermal profile of the devices is also related to the leakage power consumption and...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2010

    Tracking Games in Mobile Networks

    Users of mobile networks can change their identifiers in regions called mix zones in order to defeat the attempt of third parties to track their location. Mix zones must be deployed carefully in the network to reduce the cost they induce on mobile users and to provide high location privacy....

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2010

    Using Social Software for Teamwork and Collaborative Project Management in Higher Education

    This paper discusses the potential role of social software in supporting teamwork and collaborative project management in higher education. Based on the fact that social software has been widely spread among young students nowadays, using it for collaborative learning is believed to increase students' involvement and create learning incentives. Two...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Apr 2014

    A Computationally Efficient Limited Memory CMA-ES for Large Scale Optimization

    The authors propose a computationally efficient Limited Memory Co-variance Matrix Adaptation Evolution Strategy for large scale optimization, which they call the LM-CMA-ES. The LM-CMA-ES is a stochastic, derivative-free algorithm for numerical optimization of non-linear, non-convex optimization problems in continuous domain. Inspired by the limited memory BFGS method, the LM- CMA-ES...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2013

    Task Scheduling for Highly Concurrent Analytical and Transactional Main-Memory Workloads

    Task scheduling typically employs a worker thread per hardware context to process a dynamically changing set of tasks. It is an appealing solution to exploit modern multi-core processors, as it eases parallelization and avoids unnecessary context switches and their associated costs. Naively bundling DBMS operations into tasks, however, can result...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Aug 2013

    Improving Flash Write Performance by Using Update Frequency

    Solid-State Drives (SSDs) are quickly becoming the de-fault storage medium as the cost of NAND ash memory continues to drop. However, ash memory introduces new challenges, as data cannot be efficiently updated in-place. To overcome the technology's limitations, SSDs incorporate a software Flash Translation Layer (FTL) that implements out-of-place updates,...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2009

    A Flexible DSP Block to Enhance FPGA Arithmetic Performance

    The authors propose a new DSP block for use in modern high-performance FPGAs. Current DSP blocks contain fixed bit-width multipliers that can be combined efficiently to form larger multipliers. Their approach is similar, but includes a bypass layer following the partial product generator that exposes the compressor tree used for...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Apr 2007

    Optimal Polynomial-Time Interprocedural Register Allocation for High-Level Synthesis Using SSA Form

    An optimal, polynomial-time algorithm for interprocedural register allocation in high-level synthesis and ASIP design is presented. The algorithm determines the minimum number of registers required to store all scalar variables in an application without spilling any to memory. Although an optimal polynomial-time algorithm has been presented in the past for...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Apr 2007

    Interconnect Optimization for High-Level Synthesis of SSA Form Programs

    Register allocation for programs in Static Single Assignment (SSA) form has a polynomial-time solution because interference graphs for procedures in this representation are chordal graphs. This paper explores a complementary problem which is NP-complete: the assignment of registers to variables in order to minimize interconnect costs. In particular, the authors...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2008

    MPSoC Design Using Application-Specific Architecturally Visible Communication

    In this paper, the authors advocate the placement of Architecturally Visible Communication (AVC) buffers between adjacent cores in MPSoCs to provide high-throughput communication for streaming applications. Producer/consumer relationships map poorly onto cache-based MPSoCs. Instead, they instantiate application specific AVC buffers on top of a distributed consistent and coherent cache-based system...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2010

    On the Complexity of the Port Assignment Problem for Binary Commutative Operators in High-Level Synthesis

    In this paper, the author's present formulation of the port assignment problem for binary commutative operators tries to minimize the number of wires connected to both the left and right inputs of the operator; intuitively, this minimizes the total number of inputs connected to both inputs, which reduces the size...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2009

    Scalable and Low Cost Design Approach for Variable Block Size Motion Estimation (VBSME)

    Variable Block Size Motion Estimation (VBSME) in state-of-the-art video coding standards is one of the key features which improves the coding efficiency significantly compared to the previous standards. VBSME hardware design is a challenging task due to its complexity. The processing power requirement for VBSME depends on many factors such...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Aug 2007

    Optimal Polynomial-Time Interprocedural Register Allocation for High-Level Synthesis and ASIP Design

    Register allocation, in high-level synthesis and ASIP design, is the process of determining the number of registers to include in the resulting circuit or processor. The goal is to allocate the minimum number of registers such that no scalar variable is spilled to memory. Previously, an optimal polynomial-time algorithm for...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2009

    Architectural Support for the Orchestration of Fine-Grained Multiprocessing for Portable Streaming Applications

    Handheld devices are expected to start using fine-grained ASIC accelerators to meet energy-efficiency requirements of increasingly complex applications, e.g., video decoding and reconfigurable radio. To avoid overhead, static multiprocessor schedules are preferable for orchestrating fine-grained accelerators. However, as modern applications use accelerators in irregular patterns, static scheduling leads to low...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jun 2009

    Exploiting Fast Carry-Chains of FPGAs for Designing Compressor Trees

    Fast carry chains featuring dedicated adder circuitry is a distinctive feature of modern FPGAs. The carry chains bypass the general routing network and are embedded in the logic blocks of FPGAs for fast addition. Conventional intuition is that such carry chains can be used only for implementing carry-propagate addition; state-of-the-art...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jun 2009

    Using 3D Integration Technology to Realize Multi-Context FPGAs

    In this paper, the authors advocate the use of 3D integration technology to stack a DRAM on top of an FPGA. The DRAM will store future FPGA contexts. A configuration is read from the DRAM into a latch array on the DRAM layer while the FPGA executes; the new configuration...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2009

    Economic Aspects of Cloud Computing

    The new paradigm of cloud computing is taking over individual and business computation tasks. The cloud is dissociated from super-computers offering computational services in the early information age by the following. Cloud computing provides a solid framework for resource planning, the most crucial problem of the IT industry, as well...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jul 2009

    Pathchecker: An RFID Application for Tracing Products in Supply-Chains

    This paper presents an application of RFIDs for supply-chain management. In the application, it considers two types of readers. On one part, one has readers that will mark tags at given points. After that, these tags can be checked by another type of readers to tell whether a tag has...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2009

    Malicious Traffic Detection in Local Networks With Snort

    Snort is an open source Network Intrusion Detection System combining the benefits of signature, protocol and anomaly based inspection and is considered to be the most widely deployed IDS/IPS technology worldwide. However, Snort's deployment in a large corporate network poses different problems in terms of performance or rule selection. This...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Multi-Radio Diversity in Wireless Networks

    This paper describes the Multi-Radio Diversity (MRD) wireless system, which uses path diversity to improve loss resilience in Wireless Local Area Networks (WLANs). MRD coordinates wireless receptions among multiple radios to improve loss resilience in the face of path-dependent frame corruption over the radio. MRD incorporates two techniques to recover...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Analysis of Supportable Rates in Symmetric Blocking Wavelength Routers

    Constructing an n ? n non-blocking wavelength router using n ? n optical cross-connects may be impractical due to certain constraints such as the cost or space limitations. Moreover, in many cases the traffic requirements can be handled without a non-blocking router. In this paper, the authors study blocking wavelength...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2010

    The Improbable Differential Attack: Cryptanalysis of Reduced Round CLEFIA

    In this paper the authors present a new statistical cryptanalytic technique that they call improbable differential cryptanalysis which uses a differential that is less probable when the correct key is used. The authors provide data complexity estimates for this kind of attacks and they also show a method to expand...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Indexing Data-Oriented Overlay Networks

    The application of structured overlay networks to implement index structures for data-oriented applications such as peer-to-peer databases or peer-to-peer information retrieval, requires highly efficient approaches for overlay construction, as changing application requirements frequently lead to re-indexing of the data and hence (re-)construction of overlay networks. This problem has so far...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2009

    Hierarchical Routing Over Dynamic Wireless Networks

    A major challenge in the design of wireless ad hoc networks is the need for distributed routing algorithms that consume a minimal amount of network resources. This is particularly important in dynamic networks, where the topology can change over time, and therefore routing tables must be updated frequently. Such updates...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Apr 2010

    Gaussian Diamond Network With Adversarial Jammer

    In this paper the authors consider communication from a source to a destination over a wireless network with the help of a set of authenticated relays. They focus on a special "Diamond" network, where there is no direct link between the source and the destination; however the relay nodes help...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jun 2009

    Network Coding: From Theory to Media Streaming

    The traditional multimedia coding and streaming architectures have been challenged in the recent years with emerging applications such as wireless low-power surveillance, multimedia sensor networks, and portable devices with multimedia coding and communication capabilities. The widespread deployment of efficient communication systems combined with the proliferation of digital media content from...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // May 2011

    Chebyshev Polynomial Approximation for Distributed Signal Processing

    Unions of graph Fourier multipliers are an important class of linear operators for processing signals defined on graphs. The authors present a novel method to efficiently distribute the application of these operators to the high-dimensional signals collected by sensor networks. The proposed method features approximations of the graph Fourier multipliers...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    A Real-Time Compressed Sensing-Based Personal Electrocardiogram Monitoring System

    Wireless Body Sensor Networks (WBSN) hold the promise to enable next-generation patient-centric mobile-cardiology systems. A WBSN-enabled ElectroCardioGram (ECG) monitor consists of wearable, miniaturized and wireless sensors able to measure and wirelessly report cardiac signals to a WBSN coordinator, which is responsible for reporting them to the tele-health provider. However, state-of-the-art...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2010

    Tracking of Mobile Devices Through Bluetooth Contacts

    The authors investigate if it is possible to reconstruct a mobile phone's mobility using its Bluetooth contacts with other mobile devices, some of which are equipped with GPS receivers. The data mining analysis, based on two different data sets, shows that in certain environments coarse grained mobility of a significant...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2010

    Thermal-Aware Compilation for Register Window-Based Embedded Processors

    The development of compiler-based mechanisms to optimize the thermal profile of large register files to improve the processor reliability has become an important issue. Thermal hotspots have been known to cause severe reliability issues, while the thermal profile of the devices is also related to the leakage power consumption and...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2010

    HOLLOWS: A Power-Aware Task Scheduler for Energy Harvesting Sensor Nodes

    Energy Harvesting Sensor Nodes (EHSNs) have stringent low-energy consumption requirements, but they need to concurrently execute several types of tasks (processing, sensing, actuation, etc.). Furthermore, no accurate models exist to predict the energy harvesting income in order to adapt at run-time the executing set of prioritized tasks. In this paper,...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Local Binary Patterns as an Image Preprocessing for Face Authentication

    One of the major problems in face authentication systems is to deal with variations in illumination. In a realistic scenario, it is very likely that the lighting condition of the probe image does not correspond to those of the gallery image, hence there is a need to handle such variations....

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2011

    Survivable Mapping Algorithm by Ring Trimming (SMART) for Large IP-Over-WDM Networks

    The authors develop a fast and efficient algorithm that finds a survivable (i.e., robust to single fiber failures) mapping of IP topology on the mesh of fibers in IP-over-WDM networks; they call it SMART. A number of algorithms solving this problem can be found in the literature. Since ILP solutions...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Feb 2011

    Autonomic SLA-Driven Provisioning for Cloud Applications

    Significant achievements have been made for automated allocation of cloud resources. However, the performance of applications may be poor in peak load periods, unless their cloud resources are dynamically adjusted. Moreover, although cloud resources dedicated to different applications are virtually isolated, performance fluctuations do occur because of resource sharing, and...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2010

    Using Social Software for Teamwork and Collaborative Project Management in Higher Education

    This paper discusses the potential role of social software in supporting teamwork and collaborative project management in higher education. Based on the fact that social software has been widely spread among young students nowadays, using it for collaborative learning is believed to increase students' involvement and create learning incentives. Two...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Jan 2010

    Towards Better Entity Resolution Techniques for Web Document Collections

    As person names are non-unique, the same name on different Web pages might or might not refer to the same real-world person. This entity identification problem is one of the most challenging issues in realizing the Semantic Web or entity-oriented search. The authors address this disambiguation problem, which is very...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Mar 2010

    From Web Data to Entities and Back

    The information need of Web users is often related to their understanding and interpretation of real-world entities and their relationships. For example, some-one might be interested in information about Paris, the picturesque capital of France. This mental interpretation of humans is very challenging to capture, thus information systems need a...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Aug 2009

    Mapping Web Personal Learning Environments

    A recent trend in education and in web development is to build learning environment on top of web platforms which are carefully designed to host a plurality of software components (sometimes called widgets or plugins) which can be organized or combined (mashed-up) at user's convenience to create personalized environments. The...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Feb 2010

    Affordable SLAM Through the Co-Design of Hardware and Methodology

    Simultaneous Localization And Mapping (SLAM) is a prominent feature for autonomous robots operating in undefined environments. Application's areas such as consumer robotics appliances would clearly benefit from low-cost and compact SLAM implementations. The SLAM research community has developed several robust algorithms in the course of the last two decades. However,...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Sep 2010

    Tracking Games in Mobile Networks

    Users of mobile networks can change their identifiers in regions called mix zones in order to defeat the attempt of third parties to track their location. Mix zones must be deployed carefully in the network to reduce the cost they induce on mobile users and to provide high location privacy....

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Oct 2010

    Improving API Documentation for Java-Like Languages

    The Javadoc paradigm for displaying API documentation to users is quite popular, with similar variants existing for many mainstream languages. However, two user interface design properties of Javadoc may reduce its utility when displaying documentation for APIs that make use of inheritance and parametric polymorphism. First, Javadoc does not show...

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // May 2009

    Computer Code as a Medium for Human Communication: Are Programming Languages Improving?

    Programming languages are not only useful to command computers, they also increasingly are a medium for human communication. The authors will use the framework of distributed cognition to discuss how knowledge is shared in a team of programmers and to show that computer code plays an important role in it....

    Provided By Ecole Polytechnique Federale de Lausanne

  • White Papers // Feb 2010

    An Adaptive System for Real-Time Scalable Video Streaming With End-to-End QoS Control

    This paper presents a real-time adaptive video streaming system based on the latest standardized video codec H.264/MPEG-4 AVC scalable extension (SVC). The system provides a full MPEG-21 media access framework over heterogeneous networks and terminals with end-to-end QoS control and multimedia adaptation based on SVC. This adaptive streaming system is...

    Provided By Ecole Polytechnique Federale de Lausanne