Imperial College London

Displaying 1-40 of 109 results

  • White Papers // Oct 2013

    Managing Emergencies Optimally Using a Random Neural Network-Based Algorithm

    Emergency rescues require that first responders provide support to evacuate injured and other civilians who are obstructed by the hazards. In this case, the emergency personnel can take actions strategically in order to rescue people maximally, efficiently and quickly. The paper studies the effectiveness of a Random Neural Network (RNN)-based...

    Provided By Imperial College London

  • White Papers // Jun 2013

    SQOWL2: Transactional Type Inference for OWL 2 DL in an RDBMS

    SQOWL2 is a compiler which allows an RDBMS to support sound reasoning of SROIQ(D) description logics, by implementing ontologies expressed in the OWL 2 DL language as a combination of tables and triggers in the RDBMS. The reasoning process is divided into two phases of classification of the T-Box and...

    Provided By Imperial College London

  • White Papers // May 2013

    Mobile Network Anomaly Detection and Mitigation: The NEMESYS Approach

    Mobile malware and mobile network attacks are becoming a significant threat that accompanies the increasing popularity of smart phones and tablets. Thus in this paper, the authors present their research vision that aims to develop a network-based security solution combining analytical modeling, simulation and learning, together with billing and control-plane...

    Provided By Imperial College London

  • White Papers // Apr 2013

    Low-Complexity Scheduling Policies for Energy Harvesting Communication Networks

    A time-slotted multiple access wireless system with N transmitting nodes, each equipped with an Energy Harvesting (EH) device and a rechargeable battery of finite capacity, is studied. The energy arrival process at each node is modeled as an independent two-state Markov process, such that a node either harvests one unit...

    Provided By Imperial College London

  • White Papers // Oct 2012

    WikiSensing: An Online Collaborative Approach for Sensor Data Management

    This paper presents a new methodology for collaborative sensor data management known as WikiSensing. It is a novel approach that incorporates online collaboration with sensor data management. The authors introduce the work on this research by describing the motivation and challenges of designing and developing an online collaborative sensor data...

    Provided By Imperial College London

  • White Papers // Jun 2012

    Lightweight Resource Scaling for Cloud Applications

    Elastic resource provisioning is a key feature of cloud computing, allowing users to scale up or down resource allocation for their applications at run-time. To date, most practical approaches to managing elasticity are based on allocation/de-allocation of the Virtual Machine (VM) instances to the application. This VM-level elasticity typically incurs...

    Provided By Imperial College London

  • White Papers // Jun 2012

    Resilient Emergency Evacuation Using Opportunistic Communications

    The authors describe an emergency Evacuation Support System (ESS) that employs short-range wireless communications among mobile devices carried by civilians. Emergency information is disseminated via opportunistic contacts between Communication Nodes (CNs), and each CN provides adaptive step-by-step navigation directions for its user during evacuation. Using mobile devices and opportunistic communications...

    Provided By Imperial College London

  • White Papers // May 2012

    Privacy-Preserving Location and Mobility Management to Support Tether-Free Patients in Ad-Hoc Networks

    A major driver of healthcare cost is the inefficiencies associated keeping less-critical patients overnight in the hospital when these patients could be treated as outpatients and received comparable quality of care. To this end, the authors propose the concept of tether-free patient to support patient mobility and ensure privacy-preserving healthcare....

    Provided By Imperial College London

  • White Papers // Mar 2012

    MODACLOUDS: A Model-Driven Approach for the Design and Execution of Applications on Multiple Clouds

    Cloud computing is emerging as a major trend in the ICT industry. While most of the attention of the research community is focused on considering the perspective of the cloud providers, offering mechanisms to support scaling of resources and interoperability and federation between clouds, the perspective of developers and operators...

    Provided By Imperial College London

  • White Papers // Mar 2012

    MODACLOUDS, a Model-Driven Approach for the Design and Execution of Applications on Multiple Clouds

    Cloud computing is emerging as a major trend in the ICT industry. While most of the attention of the research community is focused on considering the perspective of the Cloud providers, offering mechanisms to support scaling of resources and interoperability and federation between Clouds, the perspective of developers and operators...

    Provided By Imperial College London

  • White Papers // Mar 2012

    NaaS: Network-as-a-Service in the Cloud

    Cloud computing realises the vision of utility computing. Tenants can benefit from on-demand provisioning of computational resources according to a pay-per-use model and can outsource hardware purchases and maintenance. Tenants, however, have only limited visibility and control over network resources. Even for simple tasks, tenants must resort to inefficient overlay...

    Provided By Imperial College London

  • White Papers // Mar 2012

    Pervasive Emergency Support Systems for Building Evacuation

    An emergency situation taking place inside a confined space, such as a building, is a challenging task due to the presence of dynamic conditions. Pervasive systems can prove beneficial for the evacuation procedure, as they can provide directions to the evacuees regarding the best available exit. In this paper, the...

    Provided By Imperial College London

  • White Papers // Jan 2012

    Towards a Program Logic for JavaScript

    JavaScript has become the most widely used language for client-side web programming. The dynamic nature of JavaScript makes understanding its code notoriously difficult, leading to buggy programs and a lack of adequate static-analysis tools. The authors believe that logical reasoning has much to offer JavaScript: a simple description of program...

    Provided By Imperial College London

  • White Papers // Dec 2011

    Migrating Auctioneers on Internet Auctions for Improved Utility and Performance

    The paper studies a technique to improve the utility and performance of an automated auction application where the auctioneer and bidders communicate through the Internet. The lack of quality-of-service guarantees from site to site can severely influence the results of an auction by affecting the seller's income rate, auction fairness,...

    Provided By Imperial College London

  • White Papers // Oct 2011

    Secure Execution of Distributed Session Programs

    The development of the SJ Framework for session-based distributed programming is part of recent and ongoing research into integrating session types and practical, real-world programming languages. SJ programs featuring session types (protocols) are statically checked by the SJ compiler to verify the key property of communication safety, meaning that parties...

    Provided By Imperial College London

  • White Papers // Sep 2011

    Energy Efficient Resource Allocation Strategy for Cloud Data Centres

    Cloud computing data centres are emerging as new candidates for replacing traditional data centres. Cloud data centres are growing rapidly in both number and capacity to meet the increasing demands for highly-responsive computing and massive storage. Making the data centre more energy efficient is a necessary task. In this paper,...

    Provided By Imperial College London

  • White Papers // Aug 2011

    A New Distributed Optimization Framework for Hybrid Ad-Hoc Networks

    The continuously increasing demand for resources in modern networks urges for more efficient resource allocation. Such an allocation of resources to network users can be formulated as an optimization problem. However, the existence of wireless links in modern networks and the competition for resources by multimedia applications turn the optimization...

    Provided By Imperial College London

  • White Papers // Jun 2011

    Hierarchical Mobility Control for Data Ferries Under Constrained Message Delays

    The authors consider the problem of controlling mobile data ferries for message delivery among disconnected, scattered domains in a highly partitioned network. Existing work on data ferry control mostly focuses on predetermined ferry routes, assuming full observations at the ferry and no explicit Quality of Service (QoS) constraints on the...

    Provided By Imperial College London

  • White Papers // Jun 2011

    The Emergence Of Leadership In Social Networks

    The authors study a networked version of the minority game in which agents can choose to follow the choices made by a neighbouring agent in a social network. They show that for a wide variety of networks a leadership structure always emerges, with most agents following the choice made by...

    Provided By Imperial College London

  • White Papers // May 2011

    Intelligent Navigation Systems for Building Evacuation

    Intelligent navigation systems can significantly improve the evacuation of civilians in urban emergencies by providing dynamic directions to the evacuees as the hazard spreads. In this paper, the authors propose two distributed and adaptive systems for building evacuation. The first system, called Intelligent Evacuation System (IES), is composed of a...

    Provided By Imperial College London

  • White Papers // May 2011

    Rule-Based Verification of Network Protocol Implementations Using Symbolic Execution

    The secure and correct implementation of network protocols for resource discovery, device configuration and network management is complex and error-prone. Protocol specifications contain ambiguities, leading to implementation flaws and security vulnerabilities in network daemons. Such problems are hard to detect because they are often triggered by complex sequences of packets...

    Provided By Imperial College London

  • White Papers // May 2011

    Packets Traveling in Non-Homogeneous Networks

    This paper considers a probability model for travel of a packet from a source node to a destination node in a large non-homogeneous multiple hop network with unreliable routing tables. Use of a random model is justified by the lack of precise information that can be used in each step...

    Provided By Imperial College London

  • White Papers // Apr 2011

    PHP Aspis: Using Partial Taint Tracking to Protect Against Injection Attacks

    Web applications are increasingly popular victims of security attacks. Injection attacks, such as Cross Site Scripting or SQL Injection, are a persistent problem. Even though developers are aware of them, the suggested best practices for protection are error prone: unless all user input is consistently filtered, any application may be...

    Provided By Imperial College London

  • White Papers // Apr 2011

    YA-MAC: Handling Unified Unicast and Broadcast Traffic in Multi-Hop Wireless Sensor Networks

    This paper introduces YA-MAC, an agile Medium Access Control (MAC) protocol to provide high throughput for both unicast and broadcast traffic in Duty-Cycled Multi-hop Wireless Sensor Networks (DCM-WSN). YA-MAC is implemented under the UPMA framework in TinyOS and is evaluated on TelosB and MicaZ testbeds. The authors observe that YAMAC...

    Provided By Imperial College London

  • White Papers // Mar 2011

    Network Routing Control With G-Networks

    G-Networks are queueing networks in which the novel idea of 'Negative customers' has been introduced. In contrast with the regular customers, called positive customers and treated in the normal way by a server, negative customers are also included. "Negative customers" and "Signals" can act in the network in several ways:...

    Provided By Imperial College London

  • White Papers // Mar 2011

    Energy-Aware Routing in the Cognitive Packet Network

    An Energy Aware Routing Protocol (EARP) is proposed to minimise a performance metric that combines the total consumed power in the network and the QoS that is specified for the flows. The algorithm uses source routing based on the functionalities provided by the Cognitive Packet Network (CPN), running autonomously at...

    Provided By Imperial College London

  • White Papers // Mar 2011

    Noise, Risk Premium, And Bubble

    The existence of the pricing kernel is shown to imply the existence of an ambient information process that generates market filtration. This information process consists of a signal component concerning the value of the random variable X that can be interpreted as the timing of future cash demand, and an...

    Provided By Imperial College London

  • White Papers // Mar 2011

    Constrained Mixture Models For Asset Returns Modelling

    The estimation of asset return distributions is crucial for determining optimal trading strategies. In this paper, the authors describe the constrained mixture model, based on a mixture of Gamma and Gaussian distributions, to provide an accurate description of price trends as being clearly positive, negative or ranging while accounting for...

    Provided By Imperial College London

  • White Papers // Mar 2011

    Unobtrusive Behavioral and Activity-Related Multimodal Biometrics: The ACTIBIO Authentication Concept

    Unobtrusive Authentication using ACTIvity-Related and Soft BIOmetrics (ACTIBIO) is an EU Specific Targeted REsearch Project (STREP) where new types of biometrics are combined with state-of-the-art unobtrusive technologies in order to enhance security in a wide spectrum of applications. The project aims to develop a modular, robust, multimodal biometrics security authentication...

    Provided By Imperial College London

  • White Papers // Jan 2011

    UKAIRO: Internet-Scale Bandwidth Detouring

    The performance of content distribution on the Internet is crucial for many services. While popular content can be delivered efficiently to users by caching it using content delivery networks, the distribution of less popular content is often constrained by the bandwidth of the Internet path between the content server and...

    Provided By Imperial College London

  • White Papers // Nov 2010

    SQPR: Stream Query Planning With Reuse

    When users submit new queries to a Distributed Stream Processing System (DSPS), a query planner must allocate physical resources, such as CPU cores, memory and network bandwidth, from a set of hosts to queries. Allocation decisions must provide the correct mix of resources required by queries, while achieving an efficient...

    Provided By Imperial College London

  • White Papers // Nov 2010

    Multiplicity Computing: A Vision of Software Engineering for Next-Generation Computing Platform Applications

    New technologies have recently emerged to challenge the very nature of computing: multicore processors, virtualized operating systems and networks, and data-center clouds. One can view these technologies as forming levels within a new, global computing platform. The authors aim to open a new area of research, called multiplicity computing, that...

    Provided By Imperial College London

  • White Papers // Oct 2010

    Safe Parallel Programming With Session Java

    The session-typed programming language Session Java (SJ) has proved to be an effective tool for distributed programming, promoting productivity and compile-time safety. This paper investigates the use of SJ for session-typed parallel programming, and introduces new language primitives for chained iteration and multi-channel communication. These primitives allow the efficient coordination...

    Provided By Imperial College London

  • White Papers // Oct 2010

    Conditional Density Models For Asset Pricing

    The authors model the dynamics of asset prices and associated derivatives by consideration of the dynamics of the conditional probability density process for the value of an asset at some specified time in the future. In the case where the asset is driven by Brownian motion, an associated "Master equation"...

    Provided By Imperial College London

  • White Papers // Oct 2010

    Constrained Nonsmooth Utility Maximization On The Positive Real Line

    The authors maximize the expected utility of terminal wealth in an incomplete market where there are cone constraints on the investor's portfolio process and the utility function is not assumed to be strictly concave or differentiable. They establish the existence of the optimal solutions to the primal and dual problems...

    Provided By Imperial College London

  • White Papers // Oct 2010

    Simulating the Power Consumption of Computer Networks

    The authors introduce a high-fidelity simulation model to evaluate the power consumption of computer networks derived from measured data on routers. To this end, they design and use a power consumption profiling system to parameterize the electrical power consumption of network elements in terms of data traffic. A model validation...

    Provided By Imperial College London

  • White Papers // Oct 2010

    Information-Based Models For Finance And Insurance

    In financial markets, the information that traders have about an asset is reflected in its price. The arrival of new information then leads to price changes. The 'Information-based framework' of Brody, Hughston and Macrina (BHM) isolates the emergence of information, and examines its role as a driver of price dynamics....

    Provided By Imperial College London

  • White Papers // Sep 2010

    Asset Pricing With Random Information Flow

    In the information-based approach to asset pricing the market filtration is modeled explicitly as a superposition of signals concerning relevant market factors and independent noise. The rate at which the signal is revealed to the market then determines the overall magnitude of asset volatility. By letting this information flow rate...

    Provided By Imperial College London

  • White Papers // Sep 2010

    Towards a Radio-Controlled Time Synchronized Wireless Sensor Network

    Wireless sensor networks are deployed to monitor real-world phenomena, and are seeing growing demand in commerce and industry. These networks can benefit from time synchronized clocks on distributed nodes. The precision of time synchronization depends on error elimination or reliable estimation of errors associated with synchronization message delays. This paper...

    Provided By Imperial College London

  • White Papers // Aug 2010

    A Sensor Network to Profile the Electrical Power Consumption of Computer Networks

    The authors introduce a sensor network to measure the individual power consumption of a large number of network elements in near-real time. A main application of this system is to obtain profiles of the power usage of network elements, i.e., a parameterization of power consumption with respect to workload. They...

    Provided By Imperial College London

  • White Papers // Jul 2009

    Connectivity Dynamics for Vehicular Ad-Hoc Networks in Signalized Road Systems

    In this paper, the authors analyze the connectivity dynamics of vehicular ad-hoc networks in a generic signalized urban route. Given the velocity profile of an urban route as a function of space and time, they utilize a fluid model to characterize the general vehicular traffic flow, and a stochastic model...

    Provided By Imperial College London

  • White Papers // Jul 2009

    Optimal Transmission Probabilities in VANETs With Inhomogeneous Node Distribution

    In a Vehicular Ad-hoc NETwork (VANET), the amount of interference from neighboring nodes to a communication link is governed by the vehicle density dynamics in vicinity and transmission probability of terminals. It is obvious that vehicles are distributed non-homogeneously along a road segment due to traffic controls and speed limits...

    Provided By Imperial College London

  • White Papers // Jun 2011

    Hierarchical Mobility Control for Data Ferries Under Constrained Message Delays

    The authors consider the problem of controlling mobile data ferries for message delivery among disconnected, scattered domains in a highly partitioned network. Existing work on data ferry control mostly focuses on predetermined ferry routes, assuming full observations at the ferry and no explicit Quality of Service (QoS) constraints on the...

    Provided By Imperial College London

  • White Papers // Dec 2009

    Energy-Efficient Broadcasts in Wireless Sensor Networks With Multiple Virtual Channels

    Multichannel solutions are increasingly used to cope with the problem of low capacity in sensor networks resulting from high contention during wake-up periods of nodes. The authors can consider wake-up schedules as virtual channels, because nodes using different schedules cannot communicate with each other. In this paper, they show that...

    Provided By Imperial College London

  • White Papers // Mar 2009

    Preamble Sampling MAC Protocols With Persistent Receivers in Wireless Sensor Networks

    The authors provide an analytical framework for preamble sampling techniques for MAC protocols in wireless sensor networks, from which they derive closed-form formulas for lifetime and reliability calculations. In addition to take into account transmitter behavior that controls the form and the content of the transmitted preamble, their model also...

    Provided By Imperial College London

  • White Papers // Feb 2010

    Randomized Scheduling Algorithm for Data Aggregation in Wireless Sensor Networks

    The authors consider a wireless sensor network in which a routing tree has been established to transmit the information from a set of source nodes to a data sink. The existing algorithms to schedule the transmission slots in a way that allows the data to be compressed as it moves...

    Provided By Imperial College London

  • White Papers // Jul 2010

    A Test-Based Scheduling Protocol (TBSP) for Periodic Data Gathering in Wireless Sensor Networks

    The authors propose TBSP, a TDMA protocol for gathering information periodically from multiple data sources to a central location across multiple hops. TBSP incurs a lower overhead than the existing protocols because it only requires the sensor nodes to keep track of their own schedule, whereas in the existing protocols...

    Provided By Imperial College London

  • White Papers // May 2008

    Clique-Based Location Estimations for Wireless Sensors in GPS-Free Environments

    In this paper, the authors present a distributed, self-organizing, localization method for wireless sensors and a scheme for reducing position estimate errors by employing a novel concept of cliques of nodes. They describe an applicable theoretical foundation of peer-to-peer Distance-Vector (DV) exchange algorithm, which can operate without any manual pre-configuration....

    Provided By Imperial College London

  • White Papers // Apr 2009

    Link Residual-Time Estimation for VANET Cross-Layer Design

    Traditional network design may underestimate the dependencies between different layers of the protocol stack and fail to exploit the direct coupling of physical-layer operations to the network topology. In the case of a highly dynamic network, as observed in vehicular communications, the network architecture needs to be able to optimally...

    Provided By Imperial College London

  • White Papers // Jan 2009

    Link Classification and Residual Time Estimation Through Adaptive Modeling for VANETs

    Vehicular ad hoc networks design has drawn a lot of research attention. High node mobility, an inherent characteristic of VANETs, results in short lived links and rapid topology changes; this makes traditional ad-hoc protocols inefficient for vehicle to vehicle communication. In this paper, the authors propose a cross-layer approach, where...

    Provided By Imperial College London

  • White Papers // Apr 2008

    On the Design of a Quality-of-Service Driven Routing Protocol for Wireless Cooperative Networks

    In this paper, a quality-of-service driven routing protocol is proposed for wireless cooperative networks. The key contribution of the proposed protocol is to bring the performance gain of cooperative diversity from the physical layer up to the networking layer. Specifically, the proposed protocol uses a distributed algorithm to select the...

    Provided By Imperial College London

  • White Papers // Mar 2010

    Simple Solutions for the Second Decade of Wireless Sensor Networking

    At 2010, the authors are at the effective end of the first decade of Wireless Sensor Network (WSN) research and that the aspects such as energy efficient routing have pretty much had their day as the sensing, computing and energy technologies have now moved on. There now seems to be...

    Provided By Imperial College London

  • White Papers // Mar 2009

    Deconstructing Internet Paths: An Approach for AS-Level Detour Route Discovery

    Detour paths provide overlay networks with improved performance and resilience. Finding good detour routes with methods that scale to millions of nodes is a challenging problem. The authors propose a novel approach for decentralised discovery of detour paths based on the observation that Internet paths that traverse overlapping sets of...

    Provided By Imperial College London

  • White Papers // Jan 2010

    Neighbor Discovery With Activity Monitoring in Multichannel Wireless Mesh Networks

    One way of improving performance of wireless mesh networks is to use multiple non-overlapping channels. At the same time, the mesh network must continuously self-adapt to varying radio conditions and topology changes. Thus, the authors propose a neighbor discovery protocol that fits the requirements of multichannel networks while dealing at...

    Provided By Imperial College London

  • White Papers // Mar 2010

    Presentation Abstract: Remote Elderly Care Monitoring in WASP

    The European project "Wireless Accessible Sensor Populations" (WASP) aims to develop cost-efficient solutions to facilitate WSN deployment and application-driven optimization. This paper addresses the deployment set-up and trials undertaken to enable continuous monitoring of elderly persons using unobtrusive (body-worn and ambient) wireless sensors. Such monitoring is intended to support elderly...

    Provided By Imperial College London

  • White Papers // Sep 2010

    Towards a Radio-Controlled Time Synchronized Wireless Sensor Network

    Wireless sensor networks are deployed to monitor real-world phenomena, and are seeing growing demand in commerce and industry. These networks can benefit from time synchronized clocks on distributed nodes. The precision of time synchronization depends on error elimination or reliable estimation of errors associated with synchronization message delays. This paper...

    Provided By Imperial College London

  • White Papers // Apr 2011

    YA-MAC: Handling Unified Unicast and Broadcast Traffic in Multi-Hop Wireless Sensor Networks

    This paper introduces YA-MAC, an agile Medium Access Control (MAC) protocol to provide high throughput for both unicast and broadcast traffic in Duty-Cycled Multi-hop Wireless Sensor Networks (DCM-WSN). YA-MAC is implemented under the UPMA framework in TinyOS and is evaluated on TelosB and MicaZ testbeds. The authors observe that YAMAC...

    Provided By Imperial College London

  • White Papers // May 2011

    Rule-Based Verification of Network Protocol Implementations Using Symbolic Execution

    The secure and correct implementation of network protocols for resource discovery, device configuration and network management is complex and error-prone. Protocol specifications contain ambiguities, leading to implementation flaws and security vulnerabilities in network daemons. Such problems are hard to detect because they are often triggered by complex sequences of packets...

    Provided By Imperial College London

  • White Papers // Apr 2011

    PHP Aspis: Using Partial Taint Tracking to Protect Against Injection Attacks

    Web applications are increasingly popular victims of security attacks. Injection attacks, such as Cross Site Scripting or SQL Injection, are a persistent problem. Even though developers are aware of them, the suggested best practices for protection are error prone: unless all user input is consistently filtered, any application may be...

    Provided By Imperial College London

  • White Papers // Nov 2010

    Multiplicity Computing: A Vision of Software Engineering for Next-Generation Computing Platform Applications

    New technologies have recently emerged to challenge the very nature of computing: multicore processors, virtualized operating systems and networks, and data-center clouds. One can view these technologies as forming levels within a new, global computing platform. The authors aim to open a new area of research, called multiplicity computing, that...

    Provided By Imperial College London

  • White Papers // Oct 2011

    Secure Execution of Distributed Session Programs

    The development of the SJ Framework for session-based distributed programming is part of recent and ongoing research into integrating session types and practical, real-world programming languages. SJ programs featuring session types (protocols) are statically checked by the SJ compiler to verify the key property of communication safety, meaning that parties...

    Provided By Imperial College London

  • White Papers // Feb 2009

    Adaptive Packet Prioritisation for Wireless Sensor Networks

    The cost of a large wireless sensor network consisting of hundreds of devices may only be justified if it is deployed for multiple monitoring tasks. Introducing multiple tasks to the system however raises concerns regarding resource contention and Quality of Service (QoS). For example, rapid response tasks may have strict...

    Provided By Imperial College London

  • White Papers // Aug 2010

    A Sensor Network to Profile the Electrical Power Consumption of Computer Networks

    The authors introduce a sensor network to measure the individual power consumption of a large number of network elements in near-real time. A main application of this system is to obtain profiles of the power usage of network elements, i.e., a parameterization of power consumption with respect to workload. They...

    Provided By Imperial College London

  • White Papers // May 2008

    A Multiple Criteria, Measurement-Based Admission Control Mechanism for Self-Aware Networks

    High demand and network congestion, can prevent multimedia applications and users from obtaining the network service they require for a successful operation. A way to control traffic congestion and satisfy all users' QoS requirements, without overprovisioning, is Admission Control (AC). This work presents a measurement-based AC mechanism, which improves the...

    Provided By Imperial College London

  • White Papers // Oct 2010

    Simulating the Power Consumption of Computer Networks

    The authors introduce a high-fidelity simulation model to evaluate the power consumption of computer networks derived from measured data on routers. To this end, they design and use a power consumption profiling system to parameterize the electrical power consumption of network elements in terms of data traffic. A model validation...

    Provided By Imperial College London

  • White Papers // Jun 2008

    Experimental Insights Into Quality of Information

    In this paper the authors examine the Quality of Information (QoI) at the output of a wireless sensor network by considering the difference between the monitored environment and the interpreted data produced by the network. Using practical examples in an experimental setting, they hope that their pragmatic approach may shed...

    Provided By Imperial College London

  • White Papers // May 2008

    Random Re-Routing With Traffic Reduction for Wireless Sensor Networks

    Wireless Sensor Networks carry much traffic of routine data that are measured by sensors which monitor the environment. When unusual events occur, high priority traffic are generated to report some additional and important data urgently. It is necessary to avoid the volume of background traffic delaying the smaller stream of...

    Provided By Imperial College London

  • White Papers // Mar 2011

    Network Routing Control With G-Networks

    G-Networks are queueing networks in which the novel idea of 'Negative customers' has been introduced. In contrast with the regular customers, called positive customers and treated in the normal way by a server, negative customers are also included. "Negative customers" and "Signals" can act in the network in several ways:...

    Provided By Imperial College London

  • White Papers // Apr 2010

    QoI-Aware Wireless Sensor Network Management for Dynamic Multi-Task Operations

    QoI-aware WSN O&M represents a broad area of research challenges that this paper only begins to address. Contrary to other research focusing on the network utility maximization problem with predefined utility functions, this paper employs a novel runtime design perspective where the WSN learns and optimizes the network utility by...

    Provided By Imperial College London

  • White Papers // Apr 2010

    Utility-Based Gateway Deployment for Supporting Multi-Domain DTNs

    Due to technology or policy constraints, communications across network domains usually require the intervention of gateways, and their proper deployment is crucial to the overall performance. In this paper, the authors study the problem of placing static gateways in mobile DTNs consisting of multiple domains. Given a limited gateway budget,...

    Provided By Imperial College London

  • White Papers // Jul 2009

    Enabling Inter-Domain DTN Communications by Networked Static Gateways

    Due to technology or policy constraints, communications across domains usually require the intervention of gateways, and their proper deployment is crucial to the overall system. This paper addresses the placement of static gateways in mobile DTNs. Given a limited gateway budget, the problem is to allocate this budget among selected...

    Provided By Imperial College London

  • White Papers // Jul 2009

    On the Application of Network Coding With Diversity to Opportunistic Scheduling

    In this paper, the authors study the application of network coding to opportunistic scheduling for wireless uplink channels. The key idea proposed in this paper is to always schedule the user with best channel gain for transmission, and meantime the use of network coding encourages the scheduled users to help...

    Provided By Imperial College London

  • White Papers // Feb 2010

    Public Support For Innovation, Intangible Investment And Productivity Growth In The UK Market Sector

    Pressure on public finances has increased scrutiny of public support for innovation. The authors examine two particular issues. First, there have been many recent calls for the (relatively new) UK R&D subsidy to be extended to other "Research" activities, such as software. Second, argument still rages about the efficacy of...

    Provided By Imperial College London

  • White Papers // Nov 2009

    Portfolio Decisions With Higher Order Moments

    In this paper, the authors address the global optimization of two interesting nonconvex problems in finance. They relax the normality assumption underlying the classical Markowitz mean-variance portfolio optimization model and consider the incorporation of skewness (third moment) and kurtosis (fourth moment). The investor seeks to maximize the expected return and...

    Provided By Imperial College London

  • White Papers // Aug 2008

    The Effect Of Search Frictions In Mergers

    The authors empirically study the existence and impact of search frictions in the market for corporate control in order to explain who makes acquisitions. They proxy search frictions with the board's degree of connectedness, and also with measures of geographic proximity and business similarity. Additionally, they take into account measures...

    Provided By Imperial College London

  • White Papers // Aug 2008

    On Proportional Fair Scheduling in Multi-Antenna Wireless Mesh Networks - Theoretical Analysis

    Proportional Fair Scheduling (PFS) provides good balance between throughput and fairness via multi-user diversity and game-theoretic equilibrium. Very little analytical work exists on understanding the performance of PFS. Moreover, most researches on PFS are for cellular networks and typically use linear rate model or logarithm rate model to simplify the...

    Provided By Imperial College London

  • White Papers // Jun 2008

    Fair Resource Allocation Under Rayleigh And/or Rician Fading Environments

    Proportional Fair Scheduling (PFS) provides good balance between throughput and fairness via multi-user diversity and game-theoretic equilibrium. Very little analytical work exists on understanding the performance of PFS. Most existing prior results are for networks with Rayleigh fading. In this paper, the authors provide theoretical results for PFS in general...

    Provided By Imperial College London

  • White Papers // Aug 2008

    A Distributed Scheduling Algorithm With QoS Provisions in Multi-Hop Wireless Mesh Networks

    Multi-hop Wireless Mesh Networks (WMNs) are considered a promising technology to backhaul heterogeneous data traffic from wireless access networks to the wired Internet. WMNs are expected to support various types of applications with diverse Quality of Service (QoS) requirements, such as end-to-end packet delay, throughput, and Packet-Error-Rate (PER). Recent works...

    Provided By Imperial College London

  • White Papers // Jan 2009

    An Efficient Cross-Layer Simulation Architecture for Mesh Networks

    Wireless Mesh Networks (WMNs) are emerging as a promising technology for backhauling data traffic from wireless access networks to the wired Internet. Such networks are expected to support various types of applications with different Quality of Service (QoS) requirements. In this paper, the authors provide a complete cross-layer solution for...

    Provided By Imperial College London

  • White Papers // Mar 2009

    Cross-Layer Design for QoS in Wireless Mesh Networks

    Cross-layer design for Quality of Service (QoS) in Wireless Mesh Networks (WMNs) has attracted much research interest recently. Such networks are expected to support various types of applications with different and multiple QoS and Grade-of-Service (GoS) requirements. In order to achieve this, several key technologies spanning all layers, from physical...

    Provided By Imperial College London