University of Oslo

Displaying 1-40 of 53 results

  • White Papers // Jan 2013

    Bridging Requirements Engineering and Business Process Management

    Requirement elicitation is one of the earliest phases of a requirement engineering lifecycle. However, even though years of research have gone into seeking machine support for requirements engineering, the methods used are still highly manual and the vision of automatic transfer of business analysis requirements into IT systems supporting the...

    Provided By University of Oslo

  • White Papers // Jan 2012

    Learning-Based Routing in Mobile Wireless Sensor Networks

    Limited energy supply is a chief concern when dealing with Wireless Sensor Networks (WSNs). Thus, among other issues, routing protocols for WSNs should be designed with the goal of being energy efficient in the first place. For static networks this is already a challenge, given that different domains and application...

    Provided By University of Oslo

  • White Papers // Sep 2011

    Distributed Spectrum Sensing in Cognitive Radio Networks With Fairness Consideration: Efficiency of Correlated Equilibrium

    Cooperative spectrum sensing improves the reliability of detection. However, if the secondary users are selfish, they may not collaborate for sensing. In order to address this problem, Medium Access Control (MAC) protocols can be designed to enforce cooperation among secondary users for spectrum sensing. In this paper, the authors investigate...

    Provided By University of Oslo

  • White Papers // Sep 2011

    Fostering the Usage of Process Models for Supporting Departments in Organizations

    Modeling business processes in organizations tends to be cost-, time and resource-intensive. Therefore, it is surprising that the achieved models are mostly used in a limited way. Although, the supporting departments such as Knowledge Management, Quality Management and Change Management have access to the models, the rate of use is...

    Provided By University of Oslo

  • White Papers // May 2011

    A Model-Driven Approach to Develop Adaptive Firmwares

    In a near future it is expected that most things the people rely on in their everyday life will contain sensors and electronic based information, have computing power, run embedded software and connect to networks. A multitude of heterogeneous things will operate in a highly dynamic environment and will collaborate...

    Provided By University of Oslo

  • White Papers // Apr 2011

    The State-of-the-Art in Personalized Recommender Systems for Social Networking

    With the explosion of Web 2.0 application such as blogs, social and professional networks, and various other types of social media, the rich online information and various new sources of knowledge flood users and hence pose a great challenge in terms of information overload. It is critical to use intelligent...

    Provided By University of Oslo

  • White Papers // Mar 2011

    Secure Satellite Communication Systems Design With Individual Secrecy Rate Constraints

    In this paper, the authors study multibeam satellite secure communication through PHYsical (PHY) layer security techniques, i.e., joint power control and beamforming. By first assuming that the Channel State Information (CSI) is available and the beamforming weights are fixed, a novel secure satellite system design is investigated to minimize the...

    Provided By University of Oslo

  • White Papers // Mar 2011

    Stir: Spontaneous Social Peer-to-Peer Streaming

    Dealing with a high churn rate is very challenging in live peer-to-peer streaming. State-of-the-art studies try to mitigate the problem by exploiting peer dynamic models, analyzing traces from real world systems, or using enhanced coding techniques, e.g., network coding. Applications of social networking in peer-to-peer systems, especially on file sharing,...

    Provided By University of Oslo

  • White Papers // Feb 2011

    Two-Way Training Design for Discriminatory Channel Estimation in Wireless MIMO systems

    This paper examines the use of two-way training in Multiple-Input Multiple-Output (MIMO) wireless systems to discriminate the channel estimation (and, thus, data detection) performance between two receivers, namely, a Legitimate Receiver (LR) and an Unauthorized Receiver (UR). This paper extends upon the Discriminatory Channel Estimation (DCE) proposed in the authors'...

    Provided By University of Oslo

  • White Papers // Feb 2011

    Hierarchical Coalition Formation Game of Relay Transmission in IEEE 802.16m

    One of the main features of IEEE 802.16m is the relay transmission which could not only extend the service coverage, but also improve the Quality-of-Service (QoS) to the mobile stations. In this paper, the authors consider the cooperation among relay stations and mobile stations to improve the performance of relay...

    Provided By University of Oslo

  • White Papers // Jan 2011

    How Much Training is Needed Against Smart Jamming?

    This paper studies training-based transmissions over Multiple-Input Multiple-Output (MIMO) fading channels in the presence of jamming. Each transmission block consists of a training phase and a data transmission phase. From an information theoretic viewpoint, the authors formulate a max-min problem on the energy allocation between the two phases. The legitimate...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Efficient Cooperative Protocols for General Outage-Limited Multihop Wireless Networks

    Due to the limited energy supplies of nodes in wireless networks, achieving energy efficiency is crucial for extending the lifetime of these networks. Thus, the authors study efficient power allocations and transmission protocols for outage-restricted multihop wireless networks based on cooperative transmission. In such multihop networks, a number of nodes,...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Maximizing the Capacity of Wireless Networks Using Multi-Cell Access Schemes

    The authors propose a novel method for improving wireless network capacity by resorting to a so-called "Multi-Cell Access" (MCA) scheme. An MCA scheme is reminiscent of the conventional multiple access problem in multi-user networks. However, in an MCA scheme cells (rather than users) compete for access. Furthermore, an example of...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Combining Space-Time Block Codes and Multiplexing in Correlated MIMO Channels: An Antenna Assignment Strategy

    Multiplexing and space-time coding are competing ways of extracting capacity out of MIMO wireless systems. The authors address the problem of finding an optimal combination of these approaches over a MIMO array when a priori knowledge about correlation is available at the transmitter. Their approach is in the form of...

    Provided By University of Oslo

  • White Papers // Jan 2011

    A Closed-Form Precoder for Spatial Multiplexing Over Correlated MIMO Channels

    Multiple Input and Multiple Output (MIMO) systems, employing several transmit and receive antennas at both ends, are capable of providing a large increase in capacity compared to traditional single antenna systems,. This increase in capacity is however dependent upon the fact that the channels from a transmitter to a receiver...

    Provided By University of Oslo

  • White Papers // Jan 2011

    A Simple Greedy Scheme for Multicell Capacity Maximization

    The authors study joint optimization of transmit power and scheduling in a multicell wireless network. Despite promising significant gains, this problem is known to be NP-hard and thus difficult to tackle in practice. However, they show that this problem lends itself to analysis for large wireless networks which allows simpler...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Extending Orthogonal Block Codes With Partial Feedback

    Since the work of Alamouti, Space-Time Block Coding (STBC) has been an intensive area of research, with several original design strategies having been put forward recently. Because of the decoding simplicity they offer, orthogonal design approaches have been in particular focus lately. However, as was shown in, truly orthogonal full-rate...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Spatial Multiplexing Over Correlated MIMO Channels With a Closed Form Precoder

    Multiple Input and Multiple Output (MIMO) systems, employing several transmit and receive antennas at both ends, are capable of providing a large increase in capacity compared to traditional single antenna systems. This increase in capacity is however dependent upon the fact that the channels from a transmitter to a receiver...

    Provided By University of Oslo

  • White Papers // Nov 2010

    Testing The Invariance Of Expectations Models Of Inflation

    The New-Keynesian Phillips Curve (NKPC) includes expected future inflation to explain current inflation. Such models are estimated by replacing the expected value by the future outcome, using Instrumental Variables or Generalized Method of Moments methods. However, the underlying theory does not allow for various non-stationarities - although crises, breaks and...

    Provided By University of Oslo

  • White Papers // Oct 2010

    Hedonic Coalition Formation for Distributed Task Allocation Among Wireless Agents

    Autonomous wireless agents such as unmanned aerial vehicles, mobile base stations, or self-operating wireless nodes present a great potential for deployment in next-generation wireless networks. While current literature has been mainly focused on the use of agents within robotics or software engineering applications, the authors propose a novel usage model...

    Provided By University of Oslo

  • White Papers // Sep 2010

    Distributed Spectrum Sensing for Cognitive Radio Networks With Heterogeneous Traffic

    Cooperative spectrum sensing improves reliability and the detection performance of sensing. However, the fully cooperative scenario may not be realistic to assume in many cases. The authors consider a cognitive radio network with heavy traffic users and light traffic users and analyze their behavior towards sensing using the concept of...

    Provided By University of Oslo

  • White Papers // Aug 2010

    The Reliability Performance of Wireless Multi-Hop Networks With Apparent Link-Failures

    The links in an ad hoc or wireless mesh network are normally kept alive by the exchange of beacons between neighboring nodes. These beacons are prone to collisions with traffic from hidden nodes. If several beacons are lost due to overlapping transmissions, the node expecting the beacons erroneously assumes that...

    Provided By University of Oslo

  • White Papers // Aug 2010

    Optimized Group Communication for Tactical Military Networks

    In tactical networks there is a need for group communication applications, such as position and information sharing (Situational Awareness data), and Push-To-Talk (PTT) voice communication. This paper focuses on group communication in tactical military ad hoc networks, where most of the nodes are interested receivers. In this case, an efficient...

    Provided By University of Oslo

  • White Papers // Jun 2010

    Heterogeneous Firms Or Heterogeneous Workers?

    The authors expect trade liberalization to give rise to aggregate productivity gains, as the least efficient firms are forced out, and labor is reallocated towards the best performing firms. But the positive intra-industry reallocation effects rely on the assumption that exporters' superior performance is due to intrinsic firm efficiency. They...

    Provided By University of Oslo

  • White Papers // May 2010

    5G - Service Continuity in Heterogeneous Environments

    This paper introduces service continuity as the main driver for 5G systems. It addresses user- and service-aspects in recently opened LTE networks, and identifies the system challenges. The main challenges are related to radio coverage, especially for the provision of high data rates for indoor users. The paper covers also...

    Provided By University of Oslo

  • White Papers // Apr 2010

    Information Storage, Reduction and Dissemination in Sensor Networks: A Survey

    There is a large body of work addressing information storage, reduction, and dissemination in Wireless Sensor Networks (WSNs), but there seems to be no contribution giving a survey of this literature. In this paper, the authors take on such a challenge and review previous WSN research and further presents a...

    Provided By University of Oslo

  • White Papers // Apr 2010

    Automatically Deriving UML Sequence Diagrams From Use Cases

    Use cases are commonly used to structure and document requirements during requirement elicitation while sequence diagrams are often used during the analysis phase to document use cases as objects' interactions. Since creating such sequence diagrams is mostly manual, automated support would provide significant, practical help. Additionally, traceability could be easily...

    Provided By University of Oslo

  • White Papers // Feb 2010

    Quality-And Context-Aware Neighbor Selection for Layered Peer-to-Peer Streaming

    Layered streaming is being considered as the most promising approach to adapt to bandwidth variations and heterogeneous end users in streaming applications. The goal of a layered streaming protocol is not only to optimize the average playback skip rate as in single-layer streaming, but also to maximize possible quality level...

    Provided By University of Oslo

  • White Papers // Feb 2010

    Comparing The Welfare Of Growing Economies

    Economies that currently have the same productive capacity may implement different growth rates. This entails that it is insufficient to base international comparisons of welfare solely on current well-being, or introducing the potential for future growth in an arbitrary manner. NNP-based measures trade off current well-being and the potential for...

    Provided By University of Oslo

  • White Papers // Feb 2010

    Formal Semantics and Analysis of Behavioral AADL Models in Real-Time Maude

    AADL is a standard for modeling embedded systems that is widely used in avionics and other safety-critical applications. However, the AADL standard lacks at present a formal semantics, and this severely limits both unambiguous communication among model developers, and the development of simulators and formal analysis tools. In this paper,...

    Provided By University of Oslo

  • White Papers // Jan 2010

    Deployed Wireless Sensors

    The distribution of randomly deployed wireless sensors plays an important role in the quality of the methods used for data acquisition and signal reconstruction. Mathematically speaking, the estimation of the distribution of randomly deployed sensors can be related to computing the spectrum of Vandermonde matrices with non-uniform entries. In this...

    Provided By University of Oslo

  • White Papers // Jan 2010

    A Distributed Coalition Formation Framework for Fair User Cooperation in Wireless Networks

    Cooperation in wireless networks allows single antenna devices to improve their performance by forming virtual multiple antenna systems. However, performing a distributed and fair cooperation constitutes a major challenge. In this paper, the authors model cooperation in wireless networks through a game theoretical algorithm derived from a novel concept from...

    Provided By University of Oslo

  • White Papers // Jan 2010

    Governing Third-Party Development Through Platform Boundary Resources

    Third-party development is increasingly relevant for software platform owners seeking to generate complementary assets in the form of applications. The governance of such development involves two seemingly conflicting goals: the maintenance of platform control and the transfer of design capability to users. A key element in simultaneously accommodating these goals...

    Provided By University of Oslo

  • White Papers // Jan 2010

    Mixed Language Programming for High-Performance Computing Applications

    First, different styles of programming in the languages Fortran 77, C, C++, and Python are reviewed and exemplified in the context of representing and computing with sparse matrices. Special emphasis is paid to a promising multi-language environment based on using Python for administrative tasks and Fortran or C/C++ for the...

    Provided By University of Oslo

  • White Papers // Dec 2009

    Chameleon: Adaptive Peer-to-Peer Streaming With Network Coding

    Layered streaming can be used to adapt to the available download capacity of an end-user, and such adaptation is very much required in real world HTTP media streaming. The multiple layer codec has become more refined, as SVC (the scalable extension of the H.264/AVC standard) has been standardized with a...

    Provided By University of Oslo

  • White Papers // Nov 2009

    Differential Space-Time Coded Cooperation for Decode-and-Forward Based Wireless Relay Networks

    Estimating Channel State Information (CSI) in the fast fading conditions is very challenging. In this paper, a simple structure for cooperative diversity in decode-and-forward mode is examined, in which the transmitter, the relay, and the receiver do not know the CSI. In this scheme, transmission of information is done in...

    Provided By University of Oslo

  • White Papers // Nov 2009

    Distributed Coalition Formation Games for Secure Wireless Transmission

    Cooperation among wireless nodes has been recently proposed for improving the PHYsical layer (PHY) security of wireless transmission in the presence of multiple eavesdroppers. While existing PHY security literature answered the question "What are the link-level secrecy rate gains from cooperation?", this paper attempts to answer the question of "How...

    Provided By University of Oslo

  • White Papers // Oct 2009

    Increasing the Secrecy Capacity by Cooperation in Wireless Networks

    Physical layer security is an emerging security field that explores the possibilities of achieving perfect secrecy data transmission between the intended network nodes, while possible malicious nodes that eavesdrop the communication obtain zero information. In this paper, the authors observe how node cooperation improves the physical layer security of a...

    Provided By University of Oslo

  • White Papers // Sep 2009

    The Nornir Run-Time System for Parallel Programs Using Kahn Process Networks

    Shared-memory concurrency is the prevalent paradigm used for developing parallel applications targeted towards small- and middle-sized machines, but experience has shown that it is hard to use. This is largely caused by synchronization primitives which are low-level, inherently nondeterministic, and, consequently, non-intuitive to use. In this paper, the authors present...

    Provided By University of Oslo

  • White Papers // Jul 2009

    A Network-Layer Proxy for Bandwidth Aggregation and Reduction of IP Packet Reordering

    With today's widespread deployment of wireless technologies, it is often the case that a single communication device can select from a variety of access networks. At the same time, there is an ongoing trend towards integration of multiple network interfaces into end-hosts, such as cell phones with HSDPA, Bluetooth and...

    Provided By University of Oslo

  • White Papers // Feb 2010

    Comparing The Welfare Of Growing Economies

    Economies that currently have the same productive capacity may implement different growth rates. This entails that it is insufficient to base international comparisons of welfare solely on current well-being, or introducing the potential for future growth in an arbitrary manner. NNP-based measures trade off current well-being and the potential for...

    Provided By University of Oslo

  • White Papers // Feb 2011

    Hierarchical Coalition Formation Game of Relay Transmission in IEEE 802.16m

    One of the main features of IEEE 802.16m is the relay transmission which could not only extend the service coverage, but also improve the Quality-of-Service (QoS) to the mobile stations. In this paper, the authors consider the cooperation among relay stations and mobile stations to improve the performance of relay...

    Provided By University of Oslo

  • White Papers // Jan 2010

    Deployed Wireless Sensors

    The distribution of randomly deployed wireless sensors plays an important role in the quality of the methods used for data acquisition and signal reconstruction. Mathematically speaking, the estimation of the distribution of randomly deployed sensors can be related to computing the spectrum of Vandermonde matrices with non-uniform entries. In this...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Efficient Cooperative Protocols for General Outage-Limited Multihop Wireless Networks

    Due to the limited energy supplies of nodes in wireless networks, achieving energy efficiency is crucial for extending the lifetime of these networks. Thus, the authors study efficient power allocations and transmission protocols for outage-restricted multihop wireless networks based on cooperative transmission. In such multihop networks, a number of nodes,...

    Provided By University of Oslo

  • White Papers // Nov 2009

    Differential Space-Time Coded Cooperation for Decode-and-Forward Based Wireless Relay Networks

    Estimating Channel State Information (CSI) in the fast fading conditions is very challenging. In this paper, a simple structure for cooperative diversity in decode-and-forward mode is examined, in which the transmitter, the relay, and the receiver do not know the CSI. In this scheme, transmission of information is done in...

    Provided By University of Oslo

  • White Papers // Jan 2009

    A Distributed Merge and Split Algorithm for Fair Cooperation in Wireless Networks

    This paper introduces a novel concept from coalitional game theory which allows the dynamic formation of coalitions among wireless nodes. A simple and distributed merge and split algorithm for coalition formation is constructed. This algorithm is applied to study the gains resulting from the cooperation among single antenna transmitters for...

    Provided By University of Oslo

  • White Papers // Jan 2010

    A Distributed Coalition Formation Framework for Fair User Cooperation in Wireless Networks

    Cooperation in wireless networks allows single antenna devices to improve their performance by forming virtual multiple antenna systems. However, performing a distributed and fair cooperation constitutes a major challenge. In this paper, the authors model cooperation in wireless networks through a game theoretical algorithm derived from a novel concept from...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Maximizing the Capacity of Wireless Networks Using Multi-Cell Access Schemes

    The authors propose a novel method for improving wireless network capacity by resorting to a so-called "Multi-Cell Access" (MCA) scheme. An MCA scheme is reminiscent of the conventional multiple access problem in multi-user networks. However, in an MCA scheme cells (rather than users) compete for access. Furthermore, an example of...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Combining Space-Time Block Codes and Multiplexing in Correlated MIMO Channels: An Antenna Assignment Strategy

    Multiplexing and space-time coding are competing ways of extracting capacity out of MIMO wireless systems. The authors address the problem of finding an optimal combination of these approaches over a MIMO array when a priori knowledge about correlation is available at the transmitter. Their approach is in the form of...

    Provided By University of Oslo

  • White Papers // Jan 2011

    A Closed-Form Precoder for Spatial Multiplexing Over Correlated MIMO Channels

    Multiple Input and Multiple Output (MIMO) systems, employing several transmit and receive antennas at both ends, are capable of providing a large increase in capacity compared to traditional single antenna systems,. This increase in capacity is however dependent upon the fact that the channels from a transmitter to a receiver...

    Provided By University of Oslo

  • White Papers // Jan 2011

    A Simple Greedy Scheme for Multicell Capacity Maximization

    The authors study joint optimization of transmit power and scheduling in a multicell wireless network. Despite promising significant gains, this problem is known to be NP-hard and thus difficult to tackle in practice. However, they show that this problem lends itself to analysis for large wireless networks which allows simpler...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Extending Orthogonal Block Codes With Partial Feedback

    Since the work of Alamouti, Space-Time Block Coding (STBC) has been an intensive area of research, with several original design strategies having been put forward recently. Because of the decoding simplicity they offer, orthogonal design approaches have been in particular focus lately. However, as was shown in, truly orthogonal full-rate...

    Provided By University of Oslo

  • White Papers // Jan 2011

    Spatial Multiplexing Over Correlated MIMO Channels With a Closed Form Precoder

    Multiple Input and Multiple Output (MIMO) systems, employing several transmit and receive antennas at both ends, are capable of providing a large increase in capacity compared to traditional single antenna systems. This increase in capacity is however dependent upon the fact that the channels from a transmitter to a receiver...

    Provided By University of Oslo

  • White Papers // Mar 2009

    Power Allocations in Minimum-Energy SER Constrained Cooperative Networks

    In this paper, the authors propose minimum power allocation strategies for repetition-based Amplify-and-Forward (AF) relaying, given a required Symbol Error Rate (SER) at the destination. They consider the scenario where one source and multiple relays cooperate to transmit messages to the destination. They derive the optimal power allocation strategy for...

    Provided By University of Oslo

  • White Papers // Jan 2011

    How Much Training is Needed Against Smart Jamming?

    This paper studies training-based transmissions over Multiple-Input Multiple-Output (MIMO) fading channels in the presence of jamming. Each transmission block consists of a training phase and a data transmission phase. From an information theoretic viewpoint, the authors formulate a max-min problem on the energy allocation between the two phases. The legitimate...

    Provided By University of Oslo

  • White Papers // Feb 2011

    Two-Way Training Design for Discriminatory Channel Estimation in Wireless MIMO systems

    This paper examines the use of two-way training in Multiple-Input Multiple-Output (MIMO) wireless systems to discriminate the channel estimation (and, thus, data detection) performance between two receivers, namely, a Legitimate Receiver (LR) and an Unauthorized Receiver (UR). This paper extends upon the Discriminatory Channel Estimation (DCE) proposed in the authors'...

    Provided By University of Oslo

  • White Papers // May 2010

    5G - Service Continuity in Heterogeneous Environments

    This paper introduces service continuity as the main driver for 5G systems. It addresses user- and service-aspects in recently opened LTE networks, and identifies the system challenges. The main challenges are related to radio coverage, especially for the provision of high data rates for indoor users. The paper covers also...

    Provided By University of Oslo

  • White Papers // Jun 2009

    Advanced SIM Capabilities Supporting Trust-Based Applications

    The SIM cards are going through several new enhancements both in the underlying hardware and its capabilities. They are becoming secure wireless networked devices containing embedded sensors. This paper assess how this new capabilities together with the pervasiveness and security of the SIM card can support the development and design...

    Provided By University of Oslo

  • White Papers // Mar 2009

    An Analysis of the Heterogeneity and IP Packet Reordering Over Multiple Wireless Networks

    With the increasing deployment of wireless technologies, such as WLAN, HSDPA, and WiMAX, it is often the case that simultaneous coverage of several access networks is available to a single user device. In addition, devices are also often equipped with multiple network interfaces. Thus, if the authors can exploit all...

    Provided By University of Oslo

  • White Papers // Jul 2009

    A Network-Layer Proxy for Bandwidth Aggregation and Reduction of IP Packet Reordering

    With today's widespread deployment of wireless technologies, it is often the case that a single communication device can select from a variety of access networks. At the same time, there is an ongoing trend towards integration of multiple network interfaces into end-hosts, such as cell phones with HSDPA, Bluetooth and...

    Provided By University of Oslo

  • White Papers // Jan 2010

    Governing Third-Party Development Through Platform Boundary Resources

    Third-party development is increasingly relevant for software platform owners seeking to generate complementary assets in the form of applications. The governance of such development involves two seemingly conflicting goals: the maintenance of platform control and the transfer of design capability to users. A key element in simultaneously accommodating these goals...

    Provided By University of Oslo

  • White Papers // Aug 2010

    The Reliability Performance of Wireless Multi-Hop Networks With Apparent Link-Failures

    The links in an ad hoc or wireless mesh network are normally kept alive by the exchange of beacons between neighboring nodes. These beacons are prone to collisions with traffic from hidden nodes. If several beacons are lost due to overlapping transmissions, the node expecting the beacons erroneously assumes that...

    Provided By University of Oslo

  • White Papers // Aug 2010

    Optimized Group Communication for Tactical Military Networks

    In tactical networks there is a need for group communication applications, such as position and information sharing (Situational Awareness data), and Push-To-Talk (PTT) voice communication. This paper focuses on group communication in tactical military ad hoc networks, where most of the nodes are interested receivers. In this case, an efficient...

    Provided By University of Oslo

  • White Papers // Apr 2010

    Information Storage, Reduction and Dissemination in Sensor Networks: A Survey

    There is a large body of work addressing information storage, reduction, and dissemination in Wireless Sensor Networks (WSNs), but there seems to be no contribution giving a survey of this literature. In this paper, the authors take on such a challenge and review previous WSN research and further presents a...

    Provided By University of Oslo

  • White Papers // May 2011

    A Model-Driven Approach to Develop Adaptive Firmwares

    In a near future it is expected that most things the people rely on in their everyday life will contain sensors and electronic based information, have computing power, run embedded software and connect to networks. A multitude of heterogeneous things will operate in a highly dynamic environment and will collaborate...

    Provided By University of Oslo

  • White Papers // May 2009

    Strategies for Variability Transformation at Run-Time

    More and more approaches propose to use Software Product Lines (SPLs) modelling techniques to implement dynamic adaptive systems. The resulting Dynamic Software Product Lines (DSPLs) present new challenges since the variability transformations used to derive alternative configurations have to be intensively used at runtime. This paper proposes to use the...

    Provided By University of Oslo

  • White Papers // Jun 2009

    Incremental Reasoning for Multiple Inheritance

    Object-orientation supports code reuse and incremental programming. Multiple inheritance increases the power of code reuse, but complicates the binding of method calls and thereby program analysis. Behavioral sub-typing allows program analysis under an open world assumption; i.e., under the assumption that class hierarchies are extensible. However, method redefinition is severely...

    Provided By University of Oslo

  • White Papers // Feb 2010

    Formal Semantics and Analysis of Behavioral AADL Models in Real-Time Maude

    AADL is a standard for modeling embedded systems that is widely used in avionics and other safety-critical applications. However, the AADL standard lacks at present a formal semantics, and this severely limits both unambiguous communication among model developers, and the development of simulators and formal analysis tools. In this paper,...

    Provided By University of Oslo

  • White Papers // Sep 2011

    Distributed Spectrum Sensing in Cognitive Radio Networks With Fairness Consideration: Efficiency of Correlated Equilibrium

    Cooperative spectrum sensing improves the reliability of detection. However, if the secondary users are selfish, they may not collaborate for sensing. In order to address this problem, Medium Access Control (MAC) protocols can be designed to enforce cooperation among secondary users for spectrum sensing. In this paper, the authors investigate...

    Provided By University of Oslo

  • White Papers // Sep 2010

    Distributed Spectrum Sensing for Cognitive Radio Networks With Heterogeneous Traffic

    Cooperative spectrum sensing improves reliability and the detection performance of sensing. However, the fully cooperative scenario may not be realistic to assume in many cases. The authors consider a cognitive radio network with heavy traffic users and light traffic users and analyze their behavior towards sensing using the concept of...

    Provided By University of Oslo

  • White Papers // Apr 2011

    The State-of-the-Art in Personalized Recommender Systems for Social Networking

    With the explosion of Web 2.0 application such as blogs, social and professional networks, and various other types of social media, the rich online information and various new sources of knowledge flood users and hence pose a great challenge in terms of information overload. It is critical to use intelligent...

    Provided By University of Oslo

  • White Papers // Dec 2008

    Amplify Based Double-Differential Modulation for Cooperative Communications

    In this paper, the authors propose Double-Differential (DD) modulation for Amplify-And-Forward (AAF) cooperative communications system. The proposed system works very well in the presence of carrier offsets without any channel knowledge, where the previously proposed differential AAF cooperative system breaks down. They have derived the approximate Symbol Error Rate (SER)...

    Provided By University of Oslo

  • White Papers // Jan 2012

    Learning-Based Routing in Mobile Wireless Sensor Networks

    Limited energy supply is a chief concern when dealing with Wireless Sensor Networks (WSNs). Thus, among other issues, routing protocols for WSNs should be designed with the goal of being energy efficient in the first place. For static networks this is already a challenge, given that different domains and application...

    Provided By University of Oslo

  • White Papers // Sep 2009

    The Nornir Run-Time System for Parallel Programs Using Kahn Process Networks

    Shared-memory concurrency is the prevalent paradigm used for developing parallel applications targeted towards small- and middle-sized machines, but experience has shown that it is hard to use. This is largely caused by synchronization primitives which are low-level, inherently nondeterministic, and, consequently, non-intuitive to use. In this paper, the authors present...

    Provided By University of Oslo

  • White Papers // Jan 2009

    Exploiting Reconfigurable Hardware for Network Security

    One type of network security strategy is using an Intrusion Detection System (IDS). They are implementing IDS in FPGA-based (Field Programmable Gate Array) reconfigurable hardware. This is to achieve higher speed and more efficient performance of network security, as networks develop very fast with consequently more demanding constraints. This paper...

    Provided By University of Oslo

  • White Papers // Jan 2010

    Mixed Language Programming for High-Performance Computing Applications

    First, different styles of programming in the languages Fortran 77, C, C++, and Python are reviewed and exemplified in the context of representing and computing with sparse matrices. Special emphasis is paid to a promising multi-language environment based on using Python for administrative tasks and Fortran or C/C++ for the...

    Provided By University of Oslo

  • White Papers // Apr 2010

    Automatically Deriving UML Sequence Diagrams From Use Cases

    Use cases are commonly used to structure and document requirements during requirement elicitation while sequence diagrams are often used during the analysis phase to document use cases as objects' interactions. Since creating such sequence diagrams is mostly manual, automated support would provide significant, practical help. Additionally, traceability could be easily...

    Provided By University of Oslo

  • White Papers // Apr 2009

    Access Of Experts: Information And EU Decision Making

    This paper examines patterns of participation in the large expert group system under the European Commission. The authors explore competing propositions about the character of the Commission's information system, and test four hypothesis about what affects participation in the EU expert group system. The authors separate between three kinds of...

    Provided By University of Oslo

  • White Papers // Mar 2009

    Reliability and Fault Tolerance of Ultra Low Voltage High Speed Differential CMOS

    The reliability and fault tolerance of the differential ultra low voltage gate is elaborated in this paper. The gates optimal yield and defect tolerance compared to ULV gate and standard CMOS is given. The results are obtained through Monte-Carlo simulations. The transistor is one of the key components that have...

    Provided By University of Oslo

  • White Papers // Oct 2009

    Increasing the Secrecy Capacity by Cooperation in Wireless Networks

    Physical layer security is an emerging security field that explores the possibilities of achieving perfect secrecy data transmission between the intended network nodes, while possible malicious nodes that eavesdrop the communication obtain zero information. In this paper, the authors observe how node cooperation improves the physical layer security of a...

    Provided By University of Oslo