Dresden University of Technology

Displaying 1-40 of 90 results

  • White Papers // May 2014

    Latency-Aware Elastic Scaling for Distributed Data Stream Processing Systems

    Elastic scaling allows a data stream processing system to react to a dynamically changing query or event workload by automatically scaling in or out. Thereby, both unpredictable load peaks as well as underload situations can be handled. However, each scaling decision comes with a latency penalty due to the required...

    Provided By Dresden University of Technology

  • White Papers // Apr 2014

    PowerCass: Energy Efficient, Consistent Hashing Based Storage for Micro Clouds Based Infrastructure

    Consistent hash based storage systems are used in many real world applications for which energy is one of the main cost factors. However, these systems are typically designed and deployed without any mechanisms to save energy at times of low demand. The authors present an energy conserving implementation of a...

    Provided By Dresden University of Technology

  • White Papers // Apr 2014

    Lightweight Automatic Resource Scaling for Multi-Tier Web Applications

    Dynamic resource scaling is a key property of cloud computing. Users can acquire or release required capacity for their applications on-the-fly. The most widely used and practical approach for dynamic scaling based on predefined policies (rules). For example, IaaS providers such as RightScale ask application owners to manually set the...

    Provided By Dresden University of Technology

  • White Papers // Nov 2013

    Power-Latency Trade-offs in Virtualized Environments

    The adoption of server virtualization and cloud computing has enabled high flexibility of service execution in the Internet. It also promises the efficient use of resources including power. At present, the cloud infrastructure (physical machines and cloud platforms) and the services employing the infrastructure are managed by independent entities. As...

    Provided By Dresden University of Technology

  • White Papers // Nov 2013

    Combining Error Detection and Transactional Memory for Energy-efficient Computing below Safe Operation Margins

    The power envelope has become a major issue for the design of computer systems. One way of reducing energy consumption is to downscale the voltage of microprocessors. However, this does not come without costs. By decreasing the voltage, the likelihood of failures increases drastically and without mechanisms for reliability, the...

    Provided By Dresden University of Technology

  • White Papers // Oct 2013

    Elastic and Fault Tolerant Event Stream Processing Using StreamMine3G

    The massive amount of new data being generated each day by data sources such as Smartphone and sensor devices calls for new techniques to process such continues streams of data. Event Stream Processing (ESP) addresses this problem and enables users to process such data streams in (soft) real-time allowing the...

    Provided By Dresden University of Technology

  • White Papers // Jul 2013

    StreamMine3G OneClick Deploy & Monitor ESP Applications With A Single Click

    In this paper, the authors present StreamMine3G OneClick, a web based application relieving users from the burden of the complex installation and setup process of Event Stream Processing (ESP) systems such as StreamMine3G in cloud environments. Using StreamMine3G OneClick, users just upload their application logic and choose their favorite cloud...

    Provided By Dresden University of Technology

  • White Papers // Jul 2013

    RAIC Integration for Network Storages on Mobile Devices

    Systems to combine multiple network and online storage targets with implied redundancy, security and fault tolerance, so-called RAICs, have recently seen renewed discussion due to the growing popularity of convenient cloud storage service offerings. For mobile device access to RAICs, less research results are available. A \"Smartphone for the future\"...

    Provided By Dresden University of Technology

  • White Papers // Jul 2013

    Power Consumption Estimation Models for Processors, Virtual Machines, and Servers

    The power consumption of presently available internet servers and data centers is not proportional to the work they accomplish. The scientific community is attempting to address this problem in a number of ways, for example, by employing dynamic voltage and frequency scaling, selectively switching off idle or underutilized servers, and...

    Provided By Dresden University of Technology

  • White Papers // Jun 2013

    Towards Flexible Data Sharing in Multi-Device Mobility Scenarios

    For most people, computers have evolved from large stationary machines into a multitude of interconnected personal and mobile devices which can be and are used at any convenient time. Likewise, the handling of data has evolved from the traditional input-processing-output chain into more sophisticated flows which involve splitting, joining, duplication,...

    Provided By Dresden University of Technology

  • White Papers // May 2013

    Integration of Information Systems in Cloud Computing for Establishing a Long-term Profitable Customer Portfolio

    Cloud service providers are interested both in a revenue maximizing allocation of their limited capacity resources (as goal of revenue management) and the establishment of long-term business relations with their clients (as goal of customer relationship management). Confronted with these partly diametric objectives, the paper introduces a framework for integrating...

    Provided By Dresden University of Technology

  • White Papers // May 2013

    Complexity in Enterprise Architectures - Conceptualization and Introduction of a Measure From a System Theoretic Perspective

    Measurability is the essential basis for management. Although the management of complexity is a central task of CIOs and IT-architects, literature has not proposed a concrete measure to quantify complexity in enterprise architectures so far. Against this background the contribution of this paper is the introduction of a system theoretic...

    Provided By Dresden University of Technology

  • White Papers // May 2013

    The Blurring Boundaries of Work-Related and Personal Media Use: A Grounded Theory Study on the Employee's Perspective

    The ongoing consumerization of Information Technology (IT) demands to rethink the traditional paradigms of media use at the workplace. Past research has focused on the use of company IT resources for personal purposes (e.g., 'Cyber-loafing') and primarily emphasized the adverse effects. This study takes a wider perspective and includes the...

    Provided By Dresden University of Technology

  • White Papers // May 2013

    An IT Architecture Enabling Flexible Adjustment of Exploration/exploitation Trade-Off

    The trade-off between exploration of new ideas and exploitation of certainties create a need for managing a balance between those two concepts within organizations. To align with an associated strategy, the authors suggest an IT architecture with an embedded mechanism to manage this balance when trying new approaches. A prototype...

    Provided By Dresden University of Technology

  • White Papers // May 2013

    A Probabilistic Model for Estimating the Power Consumption of Processors and Network Interface Cards

    Many of the proposed mechanisms aiming to achieve energy-aware adaptations in server environments rely on the existence of models that estimate the power consumption of the server as well as its individual components. Most existing or proposed models employ performance (hardware) monitoring counters and the CPU utilization to estimate power...

    Provided By Dresden University of Technology

  • White Papers // Mar 2013

    Leveraging Transactional Memory for Energy-Efficient Computing Below Safe Operation Margins

    The power envelope has become a major issue for the design of computer systems. One way of reducing energy consumption is to downscale the voltage of microprocessors. However, this does not come without costs. By decreasing the voltage, the likelihood of failures increases drastically and without mechanisms for reliability, the...

    Provided By Dresden University of Technology

  • White Papers // Feb 2013

    Managing the Cloud Service Lifecycle From the User's View

    The concept of Cloud Computing has become indispensable in recent years. The use of distributed computing resources facilitates primarily infinite scalability and cost reductions by pay per use agreements. However, the management of cloud services is extensive with regard to the Cloud Service Lifecycle phases. The analysis of operational Cloud...

    Provided By Dresden University of Technology

  • White Papers // Jan 2013

    Personal Cloud Management Cockpit With Social or Market-Driven Asset Exchange

    Digital and physical assets such as software, data and hardware resources have historically been exchanged in a product-style wholesome transfer. Now, the rise of Cloud Computing and the increasing delivery of Everything-as-a-Service in an Internet of Services require new techniques for users to perform asset discovery, exchange and management. This...

    Provided By Dresden University of Technology

  • White Papers // Jan 2013

    Experimental Evaluation of NUMA Effects on Database Management Systems

    NUMA systems with multiple CPUs and large main memories are common today. Consequently, DataBase Management Systems (DBMSs) in data centers are deployed on NUMA systems. They serve a wide range of database use-cases, single large applications having high performance needs as well as many small applications that are consolidated on...

    Provided By Dresden University of Technology

  • White Papers // Dec 2012

    Does Live Migration of Virtual Machines Cost Energy?

    Live migration, the process of moving a Virtual Machine (VM) interruption-free between physical hosts is a core concept in modern data centers. Power management strategies use live migration to consolidate services in a cluster environment and switch off underutilized machines to save power. However, most migration models do not consider...

    Provided By Dresden University of Technology

  • White Papers // Dec 2012

    Performance Analysis of a Handover Mechanism for a Mobile Wireless Sensor Network

    Several applications have been proposed for mobile wireless sensor networks. Some of these applications require the transfer of a large amount of data in a short period of time. This is challenging, since the mobile node may be required to repeatedly establish a link with multiple relay nodes which proceed...

    Provided By Dresden University of Technology

  • White Papers // Nov 2012

    Flexible Data Distribution Policy Language and Gateway Architecture

    Concerns about the security and reliability of data storage in online systems, alias cloud storage services, have led to the design of application-independent storage overlays and controllers which guarantee security and optimality with regards to the requirements of their users. In roaming and multi-user environments, the configuration and rules steering...

    Provided By Dresden University of Technology

  • White Papers // Nov 2012

    Analysis of Overhead and Profitability in Nested Cloud Environments

    The on-demand provisioning of computing and storage resources and the corresponding pay-as-you-go billing have made cloud computing a popular paradigm to achieve a high technological utility. While most use cases can adequately be covered by the offers of existing public cloud providers, the granularity in provisioning and pricing is not...

    Provided By Dresden University of Technology

  • White Papers // Sep 2012

    Dynamic Voltage and Frequency Scaling in Multimedia Servers

    In this paper, the authors experimentally investigate the scope and usefulness of Dynamic Voltage and Frequency Scaling (DVFS) in multimedia servers. For their experiment, they considered four scaling policies, two heterogeneous servers, and two different application scenarios. In the first scenario, they used an IO-Intensive multimedia downloading application while in...

    Provided By Dresden University of Technology

  • White Papers // Sep 2012

    Linear Precoding in MISO Cognitive Channels with Causal Primary Message

    The coexistence of a Single-Input Single-Output (SISO) primary link and a Multiple-Input Single-Output (MISO) secondary link is considered in an extended cognitive radio channel setup, where the secondary transmitter has to obtain ("Learn") the primary message in a first phase rather than having non-causal knowledge of it. An achievable rate...

    Provided By Dresden University of Technology

  • White Papers // Sep 2012

    Vertical Scaling for Prioritized VMs Provisioning

    The elastic scaling of services permits one to meet service provisioning requirements (i.e., not to violate its SLAs), and to efficiently use available resources (i.e., to minimize the cost of running the application). In this paper, the authors describe a novel online controller design built on top of the Xen...

    Provided By Dresden University of Technology

  • White Papers // Sep 2012

    Autonomous Participation in Cloud Services

    A Cyber-Physical System (CPS) is a combination of multiple physical devices connected and organized by a central controlling infrastructure using a feedback-loop mechanism. In order to increase the autonomy of CPS they must be connected to rich cloud services (e.g., social software and elastic resource services) enabling more sophisticated decision...

    Provided By Dresden University of Technology

  • White Papers // Sep 2012

    A Highly-Virtualising Cloud Resource Broker

    Cloud computing infrastructure services encompass temporally, spatially and structurally coarse-grained access to computing resources. This prevents a genuine pay-per-use model for the consumer and effectively leads to over-reservation and inadequate tariffs especially for short-term, small-scale computations. The authors propose an economically motivated compensation approach to increase the granularity and utility...

    Provided By Dresden University of Technology

  • White Papers // Aug 2012

    Spot-On for Timed Instances: Striking a Balance Between Spot and On-Demand Instances

    Infrastructure as a Service (IaaS) providers currently have no knowledge of the time frame customers intend to lease resources. However, scheduling in the absence of lease time information leads to wasted resources in times of decreasing demand. The authors explore how IaaS providers can use lease times to optimize resource...

    Provided By Dresden University of Technology

  • White Papers // Jul 2012

    The Application of Business Intelligence to Higher Education: Technical and Managerial Perspectives

    Business-intelligence has proven to be an effective means of improving the decision-making within an organization. While traditionally applied to profit making private companies BI has recently been applied to public institutions as well. The authors present a case study of the application of BI to a public university. The details...

    Provided By Dresden University of Technology

  • White Papers // May 2012

    Universal Cheat-Proof Pricing for Multiple Access Channels Without SIC Under QoS Requirements

    This paper studies universal cheat-proof pricing by a repeated game for the general Multiple Access Channel (MAC) without Successive Interference Cancelation (SIC). The authors model the system by three entities: regulator, system optimizer and users. The regulator is designed to ensure the Signal-to-Interference plus Noise Ratio (SINR) based Quality-of-Service (QoS)...

    Provided By Dresden University of Technology

  • White Papers // May 2012

    Connecting Spatially Coupled LDPC Code Chains

    Recently, iterative processing on spatially coupled sparse graphs has received a lot of attention in the literature. Codes constructed from connected Spatially Coupled Low-Density Parity-Check Code (SC-LDPCC) chains are proposed and analyzed. It is demonstrated that connecting coupled chains results in improved iterative decoding performance. The constructed protograph ensembles have...

    Provided By Dresden University of Technology

  • White Papers // May 2012

    Analysis of the Power Consumption of a Multimedia Server Under Different DVFS Policies

    Dynamic Voltage and Frequency Scaling (DVFS) has been a useful power management strategy in embedded systems, mobile devices, and wireless sensor networks. Recently, it has also been proposed for servers and data centers in conjunction with service consolidation and optimal resource-pool sizing. In this paper, the authors experimentally investigate the...

    Provided By Dresden University of Technology

  • White Papers // May 2012

    Analysis of the Power and Hardware Resource Consumption of Servers Under Different Load Balancing Policies

    Most Internet applications employ some kind of load balancing policies in a cluster setting to achieve reliable service provision as well as to deal with a resource bottleneck. However, these policies may not ensure the utilization of all of the hardware resources in a server equally efficiently. This paper experimentally...

    Provided By Dresden University of Technology

  • White Papers // Mar 2012

    Evaluation of the Reliability of RSSI for Indoor Localization

    In wireless sensor networks, nodes can be static or mobile, depending on the application requirements. Dealing with mobility can pose some formidable challenges in protocol design, particularly, at the link and network layers. These difficulties require mobility adaption algorithms to efficiently localize mobile nodes and predict the quality of link...

    Provided By Dresden University of Technology

  • White Papers // Mar 2012

    Cooperative Feeder Links for Relay Enhanced Networks

    Heterogeneous networks are gaining more and more interest as one means to cope with the expected data rise in future mobile networks. The upgrade of cellular macro networks by placing relay nodes, as one option, has the benefit of avoiding any wired backhaul network, but has to be paid by...

    Provided By Dresden University of Technology

  • White Papers // Mar 2012

    Cyclostationary Detection of Cognitive Radio Systems Using GFDM Modulation

    A cognitive radio should be able to detect unused spectrum band and to change its transmission parameters in order to transmit within these free bands. To achieve this, reliable detection of incumbent signals as well as of other opportunistic signals that are using the said spectrum, is necessary. Generalized Frequency...

    Provided By Dresden University of Technology

  • White Papers // Jan 2012

    A Semantic Extension of a Hierarchical Storage Management System for Small and Medium-Sized Enterprises

    The number of company data deposited in hierarchical storage management systems heavily increases. Thus, new approaches are necessary to keep track of a data pool. This paper introduces a Semantic Storage Extension (SSE) for existing hierarchical storage management systems that allows them to exploit semantic relations between files and use...

    Provided By Dresden University of Technology

  • White Papers // Dec 2011

    Dynamic Replication Technique for Micro-Clouds Based Distributed Storage System

    In this paper, the authors investigate a dynamic replica placement strategy to achieve minimum repair time during a complete loss of datacenter in large-scale distributed object storage systems while keeping the high availability and durability of the system as well as its balanced load and minimum network latency. Specifically, they...

    Provided By Dresden University of Technology

  • White Papers // Nov 2011

    AN-Encoding Compiler: Building Safety-Critical Systems with Commodity Hardware

    In the future, the authors expect commodity hardware to be used in safety-critical applications. However, in the future commodity hardware is expected to become less reliable and more susceptible to soft errors because of decreasing feature size and reduced power supply. Thus, software-implemented approaches to deal with unreliable hardware will...

    Provided By Dresden University of Technology

  • White Papers // Nov 2013

    Combining Error Detection and Transactional Memory for Energy-efficient Computing below Safe Operation Margins

    The power envelope has become a major issue for the design of computer systems. One way of reducing energy consumption is to downscale the voltage of microprocessors. However, this does not come without costs. By decreasing the voltage, the likelihood of failures increases drastically and without mechanisms for reliability, the...

    Provided By Dresden University of Technology

  • White Papers // May 2014

    Latency-Aware Elastic Scaling for Distributed Data Stream Processing Systems

    Elastic scaling allows a data stream processing system to react to a dynamically changing query or event workload by automatically scaling in or out. Thereby, both unpredictable load peaks as well as underload situations can be handled. However, each scaling decision comes with a latency penalty due to the required...

    Provided By Dresden University of Technology

  • White Papers // Apr 2014

    Lightweight Automatic Resource Scaling for Multi-Tier Web Applications

    Dynamic resource scaling is a key property of cloud computing. Users can acquire or release required capacity for their applications on-the-fly. The most widely used and practical approach for dynamic scaling based on predefined policies (rules). For example, IaaS providers such as RightScale ask application owners to manually set the...

    Provided By Dresden University of Technology

  • White Papers // Apr 2014

    PowerCass: Energy Efficient, Consistent Hashing Based Storage for Micro Clouds Based Infrastructure

    Consistent hash based storage systems are used in many real world applications for which energy is one of the main cost factors. However, these systems are typically designed and deployed without any mechanisms to save energy at times of low demand. The authors present an energy conserving implementation of a...

    Provided By Dresden University of Technology

  • White Papers // Sep 2009

    Energy Efficiency Improvements Through Micro Sites in Cellular Mobile Radio Networks

    Efforts to increase the energy efficiency of information and communication systems in general and cellular mobile radio networks in particular have recently gained momentum. Besides positive environmental effects, lowering the energy consumption of mobile radio systems appears beneficial from an economical perspective. In this regard, the deployment of small, low...

    Provided By Dresden University of Technology

  • White Papers // Feb 2010

    Traffic Demand and Energy Efficiency in Heterogeneous Cellular Mobile Radio Networks

    Optimization of the energy efficiency is considered not only to positively contribute to the ecological assessment, but gains in importance from operator's point of view as well, since energy costs for running a mobile radio network have an increasing share of the operational expenditure. From this perspective, the utilization of...

    Provided By Dresden University of Technology

  • White Papers // Aug 2009

    Faithful Virtualization on a Real-Time Operating System

    The combination of a real-time executive and off-the-shelf time-sharing operating systems has the potential of providing both predictability and the comfort of a large application base. Isolation between the components is required to protect the real-time subsystem from a significant class of faults in the (Ever-Growing) time-sharing operating systems but...

    Provided By Dresden University of Technology

  • White Papers // Dec 2009

    Closing the Gap Between Modelling and Java

    Model-Driven Software Development is based on standardised models that are refined, transformed and eventually translated into executable code using code generators. However, creating plain text from well-structured models creates a gap that implies several drawbacks: Developers cannot continue to use their model-based tool machinery, relations between model elements and code...

    Provided By Dresden University of Technology

  • White Papers // Jun 2009

    Pulsed Multi-Layered Image Filtering: A VLSI Implementation

    Image convolution similar to the receptive fields found in mammalian visual pathways has long been used in conventional image processing in the form of Gabor masks. However, no VLSI implementation of parallel, multi-layered pulsed processing has been brought forward which would emulate this property. The authors present a technical realization...

    Provided By Dresden University of Technology

  • White Papers // Dec 2010

    Multi-Case Multi-Objective Simulated Annealing (MC-MOSA): New Approach to Adapt Simulated Annealing to Multi-Objective Optimization

    In this paper a new approach is proposed for the adaptation of the simulated annealing search in the field of the Multi-Objective Optimization (MOO). This new approach is called Multi-Case Multi-Objective Simulated Annealing (MC-MOSA). It uses some basics of a well-known recent Multi-Objective Simulated Annealing proposed by Ulungu et al.,...

    Provided By Dresden University of Technology

  • White Papers // Jul 2011

    SecCSIE: A Secure Cloud Storage Integrator for Enterprises

    Cloud computing services eliminate the need for local storage thereby lowering operational and maintenance costs. However, security and privacy concerns regarding the out-sourced data prevail. Especially in enterprise environments, sensitive internal and customer data accumulate, which are usually subject to strong legal regulations. Therefore, all the files and information need...

    Provided By Dresden University of Technology

  • White Papers // Jan 2010

    Liquidity Constrained Exporters: Trade And Futures Hedging

    The authors present a model of risk averse exporting firm subject to liquidity constraints. The firm enters an unbiased futures market to hedge exchange rate risk and may not be able to satisfy high margin calls. Then the firm is forced to prematurely liquidate the futures position. They show that...

    Provided By Dresden University of Technology

  • White Papers // Jul 2009

    Import Tariff Led Export Under-Invoicing

    Prolonged worldwide economic depression forces some economists and policy makers to demand for a tougher regulation to protect their domestic economy. If implemented, this may lead to a high tariff and non-tariff regime that ruled the pre-globalised world economy. This paper examines the consequences of a tariff protected trade regime....

    Provided By Dresden University of Technology

  • White Papers // May 2009

    Aid, Growth And Decentralization

    This paper examines whether the federal structure of aid-receiving countries matters in explaining aid effectiveness. Following the decentralization theorem, the devolution of powers should increase aid effectiveness, since local decision-makers are better informed about local needs. At the same time, decentralization has reverse effects, e.g., through coordination problems, excessive regulation,...

    Provided By Dresden University of Technology

  • White Papers // Jan 2011

    International Trade And The Role Of Market Transparency

    The paper examines the economic role of market transparency on the decision problems of an international firm. Transparency is described in terms of the informativeness of a publicly observable signal. With higher transparency, the signal conveys more precise information about the random foreign exchange rate. The authors analyze the interaction...

    Provided By Dresden University of Technology

  • White Papers // May 2010

    Tariffs And Imports Mis-Invoicing Under Oligopoly

    Mis-match of trade statistics between developed and developing countries indicate a substantial mis-invoicing of trade figures, primarily by developing country traders. This is due to the inflexible exchange rate regimes, severe import restrictions and export subsidies prevailing in LDCs. In this paper, the authors focus on the import under-invoicing due...

    Provided By Dresden University of Technology

  • White Papers // Apr 2009

    Regional Age Structure And Economic Growth: An Econometric Study For German Regions

    This paper analyses the impact of the regional age structure on growth of German regions. Based on a neoclassical growth model an augmented Solow model was derived and estimated in a spatial econometric approach. Besides labor and human capital, public spendings and urbanisation measures are controlled for. Adding the age...

    Provided By Dresden University of Technology

  • White Papers // Apr 2011

    Information Value, Export And Hedging

    The paper analyzes the interactions between the precision of information, trade and welfare within a decision framework of an exporting firm. Information in a financial market is described in terms of a publicly observable signal. With higher transparency, the signal conveys more precise information about the random foreign exchange rate....

    Provided By Dresden University of Technology

  • White Papers // Jan 2010

    Strategic Pricing Of Financial Options

    The mainstream model of option pricing is based on an exogenously given process of price movements. The implication of this assumption is that price movements are not affected by actions of market participants. However, if the authors assume that there are indeed impacts on the price movements it no longer...

    Provided By Dresden University of Technology

  • White Papers // Jun 2010

    Asymptotically Good LDPC Convolutional Codes With AWGN Channel Thresholds Close to the Shannon Limit

    Ensembles of asymptotically regular Low-Density ParityCheck (LDPC) block codes can be obtained by terminating regular LDPC Convolutional (LDPCC) codes,. The slight irregularity resulting from the termination of the convolutional codes leads to substantially better Belief Propagation (BP) decoding thresholds compared to their tail-biting version or the block codes they are...

    Provided By Dresden University of Technology

  • White Papers // Jun 2010

    Equal Gain MIMO Beamforming in the RF Domain for OFDM-WLAN Systems

    Equal Gain Beam-forming (EGB) schemes are typically applied in the baseband domain and hence require complex RF transceivers. In order to simplify the circuitry and energy consumption of the MIMO transceiver, in this paper the authors consider an EGB scheme that operates in the RF domain by means of analog...

    Provided By Dresden University of Technology

  • White Papers // Sep 2010

    Beamforming in Underlay Cognitive Radio: Null-Shaping Constraints and Greedy User Selection

    In a multiuser cognitive radio setting, multiple secondary systems coexist with multiple primary systems. The authors assume the secondary systems consist of transmitter-receiver pairs, and each transmitter is equipped with multiple antennas while all receivers use a single antenna. In this setting, the secondary transmitters are to operate under the...

    Provided By Dresden University of Technology

  • White Papers // Sep 2010

    Pricing in Noncooperative Interference Channels for Improved Energy-Efficiency

    The authors consider non-cooperative energy-efficient resource allocation in the interference channel. Energy-efficiency is achieved when each system pays a price proportional to its allocated transmit power. In non-cooperative game-theoretic notation, the power allocation chosen by the systems corresponds to the Nash equilibrium. They study the existence and characterize the uniqueness...

    Provided By Dresden University of Technology

  • White Papers // Mar 2012

    Cyclostationary Detection of Cognitive Radio Systems Using GFDM Modulation

    A cognitive radio should be able to detect unused spectrum band and to change its transmission parameters in order to transmit within these free bands. To achieve this, reliable detection of incumbent signals as well as of other opportunistic signals that are using the said spectrum, is necessary. Generalized Frequency...

    Provided By Dresden University of Technology

  • White Papers // Sep 2012

    Linear Precoding in MISO Cognitive Channels with Causal Primary Message

    The coexistence of a Single-Input Single-Output (SISO) primary link and a Multiple-Input Single-Output (MISO) secondary link is considered in an extended cognitive radio channel setup, where the secondary transmitter has to obtain ("Learn") the primary message in a first phase rather than having non-causal knowledge of it. An achievable rate...

    Provided By Dresden University of Technology

  • White Papers // May 2012

    Connecting Spatially Coupled LDPC Code Chains

    Recently, iterative processing on spatially coupled sparse graphs has received a lot of attention in the literature. Codes constructed from connected Spatially Coupled Low-Density Parity-Check Code (SC-LDPCC) chains are proposed and analyzed. It is demonstrated that connecting coupled chains results in improved iterative decoding performance. The constructed protograph ensembles have...

    Provided By Dresden University of Technology

  • White Papers // May 2012

    Universal Cheat-Proof Pricing for Multiple Access Channels Without SIC Under QoS Requirements

    This paper studies universal cheat-proof pricing by a repeated game for the general Multiple Access Channel (MAC) without Successive Interference Cancelation (SIC). The authors model the system by three entities: regulator, system optimizer and users. The regulator is designed to ensure the Signal-to-Interference plus Noise Ratio (SINR) based Quality-of-Service (QoS)...

    Provided By Dresden University of Technology

  • White Papers // Sep 2012

    Dynamic Voltage and Frequency Scaling in Multimedia Servers

    In this paper, the authors experimentally investigate the scope and usefulness of Dynamic Voltage and Frequency Scaling (DVFS) in multimedia servers. For their experiment, they considered four scaling policies, two heterogeneous servers, and two different application scenarios. In the first scenario, they used an IO-Intensive multimedia downloading application while in...

    Provided By Dresden University of Technology

  • White Papers // Dec 2012

    Does Live Migration of Virtual Machines Cost Energy?

    Live migration, the process of moving a Virtual Machine (VM) interruption-free between physical hosts is a core concept in modern data centers. Power management strategies use live migration to consolidate services in a cluster environment and switch off underutilized machines to save power. However, most migration models do not consider...

    Provided By Dresden University of Technology

  • White Papers // Dec 2012

    Performance Analysis of a Handover Mechanism for a Mobile Wireless Sensor Network

    Several applications have been proposed for mobile wireless sensor networks. Some of these applications require the transfer of a large amount of data in a short period of time. This is challenging, since the mobile node may be required to repeatedly establish a link with multiple relay nodes which proceed...

    Provided By Dresden University of Technology

  • White Papers // May 2012

    Analysis of the Power Consumption of a Multimedia Server Under Different DVFS Policies

    Dynamic Voltage and Frequency Scaling (DVFS) has been a useful power management strategy in embedded systems, mobile devices, and wireless sensor networks. Recently, it has also been proposed for servers and data centers in conjunction with service consolidation and optimal resource-pool sizing. In this paper, the authors experimentally investigate the...

    Provided By Dresden University of Technology

  • White Papers // Mar 2012

    Evaluation of the Reliability of RSSI for Indoor Localization

    In wireless sensor networks, nodes can be static or mobile, depending on the application requirements. Dealing with mobility can pose some formidable challenges in protocol design, particularly, at the link and network layers. These difficulties require mobility adaption algorithms to efficiently localize mobile nodes and predict the quality of link...

    Provided By Dresden University of Technology

  • White Papers // May 2012

    Analysis of the Power and Hardware Resource Consumption of Servers Under Different Load Balancing Policies

    Most Internet applications employ some kind of load balancing policies in a cluster setting to achieve reliable service provision as well as to deal with a resource bottleneck. However, these policies may not ensure the utilization of all of the hardware resources in a server equally efficiently. This paper experimentally...

    Provided By Dresden University of Technology

  • White Papers // Oct 2009

    Channel Reuse Improvement for Coexistence Between Access and In-Home PLC Systems With Dynamic Resource Allocation

    There are generally two application areas of the Broadband PowerLine Communications (PLC), which use the available power cables for the transmission of the telecommunication signals: Access networks and In-Home communications. The access domains are used by the service providers to provide the access network services to their customers, while the...

    Provided By Dresden University of Technology

  • White Papers // Jun 2009

    Analysis of Time and Frequency Domain Features of Accelerometer Measurements

    This paper addresses the signal processing aspect of wireless sensor networks. It analyzes several time and frequency domain features of measurements that are taken from 3D accelerometer sensors. The measurements represent various types of movements related to humans and cars. The aim is to obtain quantitative as well as qualitative...

    Provided By Dresden University of Technology

  • White Papers // Jan 2012

    A Semantic Extension of a Hierarchical Storage Management System for Small and Medium-Sized Enterprises

    The number of company data deposited in hierarchical storage management systems heavily increases. Thus, new approaches are necessary to keep track of a data pool. This paper introduces a Semantic Storage Extension (SSE) for existing hierarchical storage management systems that allows them to exploit semantic relations between files and use...

    Provided By Dresden University of Technology

  • White Papers // Jan 2011

    Large Scale Field Trial Results on Different Uplink Coordinated Multi-Point (CoMP) Concepts in an Urban Environment

    Coordinated Multi-Point (CoMP) concepts such as multi-cell joint detection and transmission, promising large improvements in spectral efficiency and fairness, appears to be an effective option to combat inter-cell interference in mobile communications. One major drawback of uplink joint detection is the large additional backhaul required when compared to a non-cooperative...

    Provided By Dresden University of Technology

  • White Papers // Oct 2010

    Uplink Ad Hoc Cooperation by Distributed Equalization Under a Constrained Backhaul

    Theoretical analysis of base station cooperation methods have proven their potential for solving interference limitation in today's cellular networks by showing immense capacity and fairness gains. However, a major downside of base station cooperation is the additional information exchanged amongst base stations which has been the motivation for recent work...

    Provided By Dresden University of Technology

  • White Papers // Sep 2009

    Correlation Properties of Large and Small-Scale Parameters From Multicell Channel Measurements

    Based on two multi-cell measurement campaigns in Berlin and Dresden, correlation properties for channel parameters to different sites and to adjacent sectors of the same site are investigated. Results indicate that the assumptions in the widely used 3GPP Spatial Channel Model (SCM) form an upper bound for the multi-cell correlations...

    Provided By Dresden University of Technology

  • White Papers // Jun 2011

    Testbed Federation: An Approach for Experimentation-Driven Research in Cognitive Radios and Cognitive Networking

    The sub-optimal exploitation of radio spectrum is widely accepted. Cognitive radio is a technology that aims to address this issue and improve the overall efficiency of radio spectrum utilization. However, this promising technology is far from being mature at present. In addition to theoretical research, experimentally-driven research is needed to...

    Provided By Dresden University of Technology