WorldWideScience

Sample records for networks ieee transactions

  1. Editorial for the IEEE Transactions on Power Electronics, January 2009

    DEFF Research Database (Denmark)

    Blaabjerg, Frede

    2009-01-01

    I am entering the fourth year as the Editor in Chief of the IEEE TRANSACTIONS ON POWER ELECTRONICS. A position like this becomes more and more important for the technical field as publishing in a peer-reviewed highly ranked journal has influence on the industrial and academic career. It is a way...

  2. Editorial for IEEE Transactions on Power Electronics

    DEFF Research Database (Denmark)

    Blaabjerg, Frede

    2007-01-01

    , this popularity creates a transient problem for many authors. The impact factor of the TRANSACTIONS has dropped significantly. This parameter was not important years ago for the PELS Society, but now, universities all over the world try to benchmark and one of their factors are publications in high impact...

  3. Editorial for IEEE Transactions on Power Electronics, January 2013

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Lehman, Brad

    2013-01-01

    The editors discuss the health of the Transactions, the rate of article submission, the time from submission to publication, and the Journal Citation Reports (JCR) Impact Factor of the Transactions and contributing factors for that value. They note that the Transactions have only 100-150 articles...... should increase the impact factor of the IEEE TRANSACTIONS ON POWER ELECTRONICS (TPEL). In 2007, TPEL published 2600 pages, and it has gradually been increased to 4000 pages in 2011, 5000 pages in 2012, and 5500 pages are projected for 2013. We have decided to publish 12 printed issues so every month...... a new issue will be printed. A graph is provided showing the number of regular papers received in the past years as well as the number of published pages in the TPEL. Finally they note that in 2008, TPEL obtained a record high value for the impact factor (as shown in a figure) but in 2009 it was reduced...

  4. 2012 IEEE Vehicular Networking Conference (VNC)

    NARCIS (Netherlands)

    Altintas, Onur; Chen, Wai; Heijenk, Geert; Oh, Hyun Seo; Chung, Jong-Moon; Dressler, Falko; Kargl, Frank; Pau, Giovanni; Schoch, Elmar

    2012-01-01

    On behalf of the Organizing Committee, we would like to welcome you to the fourth edition of the IEEE Vehicular Networking Conference in Seoul, Korea. IEEE VNC is a unique conference sponsored by both IEEE Communications Society and Intelligent Transportation Systems Society. It brings together

  5. Special NSREC 2016 Issue of the IEEE Transactions on Nuclear Science Comments by the Editors

    Science.gov (United States)

    Fleetwood, Daniel M.; Brown, Dennis; Girard, Sylvain; Gerardin, Simone; Quinn, Heather; Kobayashi, Daisuke; Esqueda, Ivan Sanchez; Robinson, William

    2017-01-01

    The January 2017 special issue of the IEEE Transactions on Nuclear Science (TNS) contains selected papers from the 53rd annual IEEE International Nuclear and Space Radiation Effects Conference (NSREC) held July 11-15, 2016, in Portland, OR, USA. The 2016 IEEE NSREC was sponsored by the IEEE Nuclear and Plasma Sciences Society. 98 of the 104 papers presented in Portland were submitted for consideration for this year's special issue. The papers that appear in this special issue successfully completed the review process before the deadline. A few additional papers may appear in subsequent issues of the Transactions.

  6. Networks and transaction costs

    DEFF Research Database (Denmark)

    Henning, Christian H.C.A.; Henningsen, Geraldine; Henningsen, Arne

    -multiple output stochastic Ray production function to generate relative shadow prices of three inputs and two outputs traded by farms. At a second stage a structural equation system is derived from the first order conditions of farm’s profit maximization to estimate simultaneously the of commodity specific...... transaction cost functions for all traded farm inputs and outputs. Estimation results based on a sample of 315 Polish farms imply a significant influence of social network structures on farm’s transaction costs. Moreover, estimated transaction costs correspond to a reasonable amount of farm specific shadow...... prices....

  7. Networks and Transaction Costs

    OpenAIRE

    Henning, Christian; Henningsen, Geraldine; Henningsen, Arne

    2011-01-01

    Based on the well-known fact that social networks can provide effective mechanisms that help to increase the trust level between two trade partners, we apply a simple game-theoretical framework to derive transaction costs as a high risk of opportunistic behavior in a repeated trade relation determined by the density and size of trading networks. In the empirical part of the paper we apply a two stage procedure to estimate the impact of social network structures on farm’s transaction costs obs...

  8. Transactional Network Platform: Applications

    Energy Technology Data Exchange (ETDEWEB)

    Katipamula, Srinivas; Lutes, Robert G.; Ngo, Hung; Underhill, Ronald M.

    2013-10-31

    In FY13, Pacific Northwest National Laboratory (PNNL) with funding from the Department of Energy’s (DOE’s) Building Technologies Office (BTO) designed, prototyped and tested a transactional network platform to support energy, operational and financial transactions between any networked entities (equipment, organizations, buildings, grid, etc.). Initially, in FY13, the concept demonstrated transactions between packaged rooftop air conditioners and heat pump units (RTUs) and the electric grid using applications or "agents" that reside on the platform, on the equipment, on a local building controller or in the Cloud. The transactional network project is a multi-lab effort with Oakridge National Laboratory (ORNL) and Lawrence Berkeley National Laboratory (LBNL) also contributing to the effort. PNNL coordinated the project and also was responsible for the development of the transactional network (TN) platform and three different applications associated with RTUs. This document describes two applications or "agents" in details, and also summarizes the platform. The TN platform details are described in another companion document.

  9. Interoperability in wireless sensor networks based on IEEE 1451 standard

    OpenAIRE

    Higuera Portilla, Jorge Eduardo; Polo Cantero, José

    2012-01-01

    The syntactic and semantic interoperability is a challenge of the Wireless Sensor Networks (WSN) with smart sensors in pervasive computing environments to increase their harmonization in a wide variety of applications. This chapter contains a detailed description of interoperability in heterogeneous WSN using the IEEE 1451 standard. This work focuses on personal area networks (PAN) with smart sensors and actuators. Also, a technical, syntactic and semantic levels of interoperability based on ...

  10. Delay Analysis of GTS Bridging between IEEE 802.15.4 and IEEE 802.11 Networks for Healthcare Applications.

    Science.gov (United States)

    Misić, Jelena; Sherman Shen, Xuemin

    2009-01-01

    We consider interconnection of IEEE 802.15.4 beacon-enabled network cluster with IEEE 802.11b network. This scenario is important in healthcare applications where IEEE 802.15.4 nodes comprise patient's body area network (BAN) and are involved in sensing some health-related data. BAN nodes have very short communication range in order to avoid harming patient's health and save energy. Sensed data needs to be transmitted to an access point in the ward room using wireless technology with higher transmission range and rate such as IEEE 802.11b. We model the interconnected network where IEEE 802.15.4-based BAN operates in guaranteed time slot (GTS) mode, and IEEE 802.11b part of the bridge conveys GTS superframe to the 802.11b access point. We then analyze the network delays. Performance analysis is performed using EKG traffic from continuous telemetry, and we discuss the delays of communication due the increasing number of patients.

  11. Attacks on IEEE 802.11 wireless networks

    Directory of Open Access Journals (Sweden)

    Dejan Milan Tepšić

    2013-06-01

    Full Text Available Security of wireless computer networks was initially secured with the WEP security protocol, which relies on the RC4 encryption algorithm and the CRC algorithm to check the integrity. The basic problems of the WEP are a short initialization vector, unsafe data integrity checking, using a common key, the lack of mechanisms for management and exchange of keys, the lack of protection from the endless insertion of the same package into the network, the lack of authentication of access points and the like. The consequences of these failures are easy attacks against the WEP network, namely their complete insecurity. Therefore, the work began on the IEEE 802.11i protocol, which should radically improve the security of wireless networks. Since the development of a protocol lasted, the WPA standard was released to offset the security gap caused by the WEP. The WPA also relies on RC4 and CRC algorithms, but brings temporary keys and the MIC algorithm for data integrity. The 802.1X authentication was introduced and common keys are no longer needed, since it is possible to use an authentication server. The length of the initialization vector was increased and the vector is obtained based on the packet serial number, in order to prevent the insertion of the same packet into the network. The weakness of the WPA security mechanism is the use of a common key. WPA2 (802.11i later appeared. Unlike the WPA mechanism that worked on old devices with the replacement of software, WPA2 requires new network devices that can perform AES encryption. AES replaces the RC4 algorithm and delivers much greater security. Data integrity is protected by encryption. Despite progress, there are still weaknesses in wireless networks. Attacks for denial of service are possible as well as spoofing package headers attacks. For now, it is not advisable to use wireless networks in environments where unreliability and unavailability are not tolerated. Introduction In the entire history of

  12. Basic security measures for IEEE 802.11 wireless networks

    Directory of Open Access Journals (Sweden)

    Oscar P. Sarmiento

    2010-05-01

    Full Text Available This article presents a tutorial/discussion of three commonly-used IEEE 802.11 wireless network security standards: WEP, WPA and WPA2. A detailed analysis of the RC4 algorithm supporting WEP is presented, including its vulnera-bilities. The WPA and WPA2 encryption protocols’ most relevant aspects and technical characteristics are reviewed for a comparative analysis of the three standards in terms of the security they provide. Special attention has been paid to WEP encryption by using an educational simulation tool written in C++ Builder for facilitating the unders-tanding of this protocol at academic level. Two practical cases of wireless security configurations using Cisco net-working equipment are also presented: configuring and enabling WPA-Personal and WPA2-Personal (these being security options used by TKIP and AES, respectively.

  13. Basic security measures for IEEE 802.11 wireless networks

    Directory of Open Access Journals (Sweden)

    Oscar P. Sarmiento

    2008-05-01

    Full Text Available This article presents a tutorial/discussion of three commonly-used IEEE 802.11 wireless network security standards: WEP, WPA and WPA2. A detailed analysis of the RC4 algorithm supporting WEP is presented, including its vulnera-bilities. The WPA and WPA2 encryption protocols’ most relevant aspects and technical characteristics are reviewed for a comparative analysis of the three standards in terms of the security they provide. Special attention has been paid to WEP encryption by using an educational simulation tool written in C++ Builder for facilitating the unders-tanding of this protocol at academic level. Two practical cases of wireless security configurations using Cisco net-working equipment are also presented: configuring and enabling WPA-Personal and WPA2-Personal (these being security options used by TKIP and AES, respectively.

  14. GE networked mass storage solutions supporting IEEE network mass storage model

    Science.gov (United States)

    Herzog, Donald

    1993-01-01

    The General Electric Government Communications Systems Department (GE/GCSD) has developed a near real time digital data storage and retrieval system that extends the capabilities currently available in today's marketplace. This system called DuraStore uses commercially available rotary tape drive technology with ANSI/IEEE standards for automated magnetic tape based data storage. It uses a nonproprietary approach to satisfy a wide range of data rates and storage capabilities requirements and is compliant with the IEEE Network Storage Model. Rotary tape drives, standard interfaces, application specific hardware/software, networked automated tape libraries, library administrator, write protection, volume/physical media linkages, and maximum resource utilization are addressed.

  15. Capacity and performance study of IEEE 802.11e in WLANs and ad hoc networks

    OpenAIRE

    Mjøberg, Frank Roar

    2007-01-01

    This master thesis focuses on the IEEE 802.11e Enhanced Distribution Channel Access (EDCA). The IEEE 802.11e protocol became an IEEE standard in November 2005 and is a very popular research topic. Even though the protocol has been tested for faults and errors a long time there are still research topics to explore. This thesis will try to answer some of those topics. The main topic in this thesis is how the IEEE 802.11e MAC operates in a multihop ad hoc network. We discuss and evaluated th...

  16. Design Optimization of Cyber-Physical Distributed Systems using IEEE Time-sensitive Networks (TSN)

    DEFF Research Database (Denmark)

    Pop, Paul; Lander Raagaard, Michael; Craciunas, Silviu S.

    2016-01-01

    In this paper we are interested in safety-critical real-time applications implemented on distributed architectures supporting the Time-SensitiveNetworking (TSN) standard. The ongoing standardization of TSN is an IEEE effort to bring deterministic real-time capabilities into the IEEE 802.1 Ethernet...

  17. ANDSF-Assisted Vertical Handover Decisions in the IEEE 802.11/LTE-Advanced Network

    OpenAIRE

    Xenakis, Dionysis; Passas, Nikos; Merakos, Lazaros; Verikoukis, Christos

    2016-01-01

    To address the challenging issues of energy-efficiency and seamless connectivity in heterogeneous networks, 3GPP and IEEE have recently incorporated several architectural and functional enhancements to the baseline operation of their standards for cellular and wireless local area network access, respectively. Based on the 3GPP Access Network Discovery and Selection Function (ANDSF) as well as the advanced measurement capabilities provided by the IEEE 802.11-2012 and the 3GPP Long Term Evoluti...

  18. Proceedings of the IEEE 2003 Neural Networks for Signal Processing Workshop

    DEFF Research Database (Denmark)

    Larsen, Jan

    methodology and real-world application domains and is widely entering into everyday solutions adopted by research and industry, going far beyond “traditional” neural networks and academic examples. As reflected in this collection, contemporary neural networks for signal processing combine many ideas from......This proceeding contains refereed papers presented at the thirteenth IEEE Workshop on Neural Networks for Signal Processing (NNSP’2003), held at the Atria-Mercure Conference Center, Toulouse, France, September 17-19, 2003. The Neural Networks for Signal Processing Technical Committee of the IEEE...... Signal Processing Society organized the workshop with sponsorship of the Signal Processing Society and the co-operation of the IEEE Neural Networks Society. The IEEE Press published the previous twelve volumes of the NNSP Workshop proceedings in a hardbound volume. This year, the bound volume...

  19. 2011 IEEE Vehicular Networking Conference (VNC): Demo Summaries

    NARCIS (Netherlands)

    Altintas, O.; Chen, W.; Heijenk, Geert; Dressler, F.; Ekici, E.; Kargl, Frank; Shigeno, H.; Dietzel, Stefan

    2011-01-01

    Foreword For the first time in its history, IEEE VNC has included this year’s demonstrations in its program. Demonstrations play an important role to expose the research community to practical aspects of research and to foster cross-fertilization among researchers both in academia and in industry.

  20. Research on IEEE 802.22.1 Beacon Networks Application%IEEE 802.22.1信标网络应用研究

    Institute of Scientific and Technical Information of China (English)

    杨大全

    2012-01-01

    Several IEEE 802.22.1 beacon devices are used to build beacon network by self-organization. IEEE 802.22.1 beacon protocol is introduced, and the decision strategies of beacon networks in the process of establishing and maintenance are discussed. IEEE 802.22.1 beacon networks sensing and information detection in WRAN device are introduced. The maximum latency before scheduling a quiet period that will ensure to capture the full information of the beacon network is given.%多个IEEE 802.22.1信标设备将自组织成信标网络.介绍了IEEE 802.22.1标准中定义的自组织方案;讨论了信标网络建立与维持过程中的判决策略;介绍了无线区域网络(WRAN)设备对IEEE 802.22.1信标网络的识别与信息获取机制;给出了确保实现对信标网络信息解析所需要安排的最大时延.

  1. Transaction costs and social networks in productivity measurement

    DEFF Research Database (Denmark)

    Henningsen, Geraldine; Henningsen, Arne; Henning, Christian H. C. A.

    2015-01-01

    and support. Hence, we use measures of a firm’s access to social networks as a proxy for the transaction costs the firm faces. We develop a microeconomic production model that takes into account transaction costs and networks. Using a data set of 384 Polish farms, we empirically estimate this model......We argue that in the presence of transaction costs, observed productivity measures may in many cases understate the true productivity, as production data seldom distinguish between resources entering the production process and resources of a similar type that are sacrificed for transaction costs....... Hence, both the absolute productivity measures and, more importantly, the productivity ranking will be distorted. A major driver of transaction costs is poor access to information and contract enforcement assistance. Social networks often catalyse information exchange as well as generate trust...

  2. Software-defined networking model for smart transformers with ISO/IEC/IEEE 21451 sensors

    Directory of Open Access Journals (Sweden)

    Longhua Guo

    2017-06-01

    Full Text Available The advanced IEC 61850 smart transformer has shown an improved performance in monitoring, controlling, and protecting the equipment in smart substations. However, heterogeneity, feasibility, and network control problems have limited the smart transformer’s performance in networks. To address these issues, a software-defined networking model was proposed using ISO/IEC/IEEE 21451 networks. An IEC-61850-based network controller was designed as a new kind of intelligent electrical device (IED. The proposed data and information models enhanced the network awareness ability and facilitated the access of smart sensors in transformer to communication networks. The performance evaluation results showed an improved efficiency.

  3. Transaction costs and social networks in productivity measurement

    DEFF Research Database (Denmark)

    Henningsen, Geraldine; Henningsen, Arne; Henning, Christian H. C. A.

    2015-01-01

    . Hence, both the absolute productivity measures and, more importantly, the productivity ranking will be distorted. A major driver of transaction costs is poor access to information and contract enforcement assistance. Social networks often catalyse information exchange as well as generate trust...... and support. Hence, we use measures of a firm’s access to social networks as a proxy for the transaction costs the firm faces. We develop a microeconomic production model that takes into account transaction costs and networks. Using a data set of 384 Polish farms, we empirically estimate this model...... and compare different parametric, semiparametric, and nonparametric model specifications. Our results generally support our hypothesis. Especially, large trading networks and dense household networks have a positive influence on a farm’s productivity. Furthermore, our results indicate that transaction costs...

  4. Energy-aware path selection metric for IEEE 802.11s wireless mesh networking

    CSIR Research Space (South Africa)

    Mhlanga, MM

    2009-01-01

    Full Text Available The IEEE 802.11s working group has commenced activities, which would lead to the development of a standard for wireless mesh networks (WMNs). The draft of 802.11s introduces a new path selection metric called airtime link metric. However...

  5. Energy-aware path selection metric for IEEE 802.11s wireless mesh networking

    CSIR Research Space (South Africa)

    Mhlanga, MM

    2009-08-01

    Full Text Available The IEEE 802.11s working group has commenced activities, which would lead to the development of a standard for wireless mesh networks (WMNs). The draft of 802.11s introduces a new path selection metric called airtime link metric. However...

  6. Analysis and design of an on-chip retargeting engine for IEEE 1687 networks

    NARCIS (Netherlands)

    Ibrahim, Ahmed Mohammed Youssef; Kerkhoff, Hans G.

    IEEE 1687 (iJTAG) standard introduces a methodology for accessing the increasing number of embedded instruments found in modern System-on-Chips. Retargeting is defined by iJTAG as the procedure of translating instrument-level patterns to system-level scan vectors for a certain network organization.

  7. Evaluation of H.264/AVC over IEEE 802.11p vehicular networks

    Science.gov (United States)

    Rozas-Ramallal, Ismael; Fernández-Caramés, Tiago M.; Dapena, Adriana; García-Naya, José Antonio

    2013-12-01

    The capacity of vehicular networks to offer non-safety services, like infotainment applications or the exchange of multimedia information between vehicles, have attracted a great deal of attention to the field of Intelligent Transport Systems (ITS). In particular, in this article we focus our attention on IEEE 802.11p which defines enhancements to IEEE 802.11 required to support ITS applications. We present an FPGA-based testbed developed to evaluate H.264/AVC (Advanced Video Coding) video transmission over vehicular networks. The testbed covers some of the most common situations in vehicle-to-vehicle and roadside-to-vehicle communications and it is highly flexible, allowing the performance evaluation of different vehicular standard configurations. We also show several experimental results to illustrate the quality obtained when H.264/AVC encoded video is transmitted over IEEE 802.11p networks. The quality is measured considering two important parameters: the percentage of recovered group of pictures and the frame quality. In order to improve performance, we propose to substitute the convolutional channel encoder used in IEEE 802.11p for a low-density parity-check code encoder. In addition, we suggest a simple strategy to decide the optimum number of iterations needed to decode each packet received.

  8. Software defined radio for cognitive wireless sensor networks : a reconfigurable IEEE 802.15.4 reconfigurable

    OpenAIRE

    Zitouni, Rafik

    2015-01-01

    The Increasing number of Wireless Sensor Networks (WSNs) applications has led industries to design the physical layer (PHY) of these networks following the IEEE 802.15.4 standard. The traditional design of that layer is on hardware suffering from a lack of flexibility of radio parameters, such as changing both frequency bands and modulations. This problem is emphasized by the scarcity of the radio-frequency spectrum. Software Defined Radio (SDR) is an attracting solution to easily reconfigure...

  9. Provision of QoS for Multimedia Services in IEEE 802.11 Wireless Network

    Science.gov (United States)

    2006-10-01

    INFORMATION SYSTEMS TECHNOLOGY PANEL SYMPOSIUM ON „DYNAMIC COMUNICATIONS MANAGEMENT ” IST-062 October 9 - 10, 2006 Piotr Lubkowski, Jaroslaw Krygier...Provision of QoS for Multimedia Services in IEEE 802.11 Wireless Network. In Dynamic Communications Management (pp. 10-1 – 10-16). Meeting Proceedings...mechanisms have been used for managing a limited bandwidth link within the IPv6 military narrowband network. The detailed description of these

  10. VOLTTRON Lite: Integration Platform for the Transactional Network

    Energy Technology Data Exchange (ETDEWEB)

    Haack, Jereme N.; Katipamula, Srinivas; Akyol, Bora A.; Lutes, Robert G.

    2013-10-31

    In FY13, Pacific Northwest National Laboratory (PNNL) with funding from the Department of Energy’s (DOE’s) Building Technologies Office (BTO) designed, prototyped and tested a transactional network platform. The platform is intended to support energy, operational and financial transactions between any networked entities (equipment, organizations, buildings, grid, etc.). Initially, in FY13, the concept demonstrated transactions between packaged rooftop units (RTUs) and the electric grid using applications or “agents” that reside on the platform, on the equipment, on local building controller or in the Cloud. This document describes the core of the transactional network platform, the Volttron Lite™ software and associated services hosted on the platform. Future enhancements are also discussed. The appendix of the document provides examples of how to use the various services hosted on the platform.

  11. Performance Evaluation of Beacon-Enabled Mode for IEEE 802.15.4 Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    M. Udin Harun Al Rasyid

    2013-12-01

    Full Text Available IEEE 802.15.5 standard support structure of star and peer-to-peer network formation. Strating from these, the cluster tree network can be built as a special case of peer-to-peer network to increse coverage area. In this paper, we provide an performance evaluation of beacon- enabled mode for IEEE 802.15.4 wireless sensor network on star and cluster topology in order to get the maximum result to apply the appropriate topology model as needed. We conduct analysis on each topology model by using the numbers of nodes from 10 nodes to 100 nodes to analyze throughput, delay, energy consumption, and probability success packet by using NS2 simulator. The simulation results show that the throughput and the probability of success packet of cluster topology are higher than that of star topology, and the energy consumption of cluster topology is lesser than that of star topology. However, cluster topology increases the delay more than star topology. Keywords: IEEE 802.15.4, wireless sensor network, beacon-enabled mode, topology, csma/ca

  12. A Novel IEEE 802.15.4e DSME MAC for Wireless Sensor Networks.

    Science.gov (United States)

    Sahoo, Prasan Kumar; Pattanaik, Sudhir Ranjan; Wu, Shih-Lin

    2017-01-16

    IEEE 802.15.4e standard proposes Deterministic and Synchronous Multichannel Extension (DSME) mode for wireless sensor networks (WSNs) to support industrial, commercial and health care applications. In this paper, a new channel access scheme and beacon scheduling schemes are designed for the IEEE 802.15.4e enabled WSNs in star topology to reduce the network discovery time and energy consumption. In addition, a new dynamic guaranteed retransmission slot allocation scheme is designed for devices with the failure Guaranteed Time Slot (GTS) transmission to reduce the retransmission delay. To evaluate our schemes, analytical models are designed to analyze the performance of WSNs in terms of reliability, delay, throughput and energy consumption. Our schemes are validated with simulation and analytical results and are observed that simulation results well match with the analytical one. The evaluated results of our designed schemes can improve the reliability, throughput, delay, and energy consumptions significantly.

  13. Impact of Delay Spread on IEEE 802.15.4a Networks with Energy Detection Receivers

    Directory of Open Access Journals (Sweden)

    P. Medina

    2010-12-01

    Full Text Available This work analyzes the impact of delay spread on IEEE 802.15.4a networks using energy detection (ED receivers.Specifically, we review the typical values for delay spread in Ultra Wide Band (UWB systems reported to date forindoor, outdoor and industrial environments, and study how the delay spread impacts the bit-error rate with andwithout Multiuser Interference (MUI.

  14. A Novel Prioritization Scheme to Improve QoS in IEEE 802.11e Networks

    Directory of Open Access Journals (Sweden)

    Navid Tadayon

    2010-01-01

    Full Text Available IEEE 802.11 WLAN utilizes a distributed function at its MAC layer, namely, DCF to access the wireless medium. Due to its distributed nature, DCF is able to guarantee working stability in a wireless medium while maintaining the assembling and maintenance cost in a low level. However, DCF is inefficient in dealing with real-time traffics due to its incapability on providing QoS. IEEE 802.11e was introduced as a supplementary standard to cope with this problem. This standard introduces an Enhanced Distributed Coordination Function (EDCF that works based on diff-Serve model and can serve multiple classes of traffics (by using different prioritizations schemes. With the emergence of new time-sensitive applications, EDCF has proved to be yet inefficient in dealing with these kinds of traffics because it could not provide network with well-differentiated QoS. In this study, we propose a novel prioritization scheme to improve QoS level in IEEE 802.11e network. In this scheme, we replace Uniform PDF with Gamma PDF, which has salient differentiating properties. We investigate the suitability and superiority of this scheme on furnishing network with well-differentiated QoS using probabilistic analysis. We strengthen our claims by extensive simulation runs.

  15. Study on additional carrier sensing for IEEE 802.15.4 wireless sensor networks.

    Science.gov (United States)

    Lee, Bih-Hwang; Lai, Ruei-Lung; Wu, Huai-Kuei; Wong, Chi-Ming

    2010-01-01

    Wireless sensor networks based on the IEEE 802.15.4 standard are able to achieve low-power transmissions in the guise of low-rate and short-distance wireless personal area networks (WPANs). The slotted carrier sense multiple access with collision avoidance (CSMA/CA) is used for contention mechanism. Sensor nodes perform a backoff process as soon as the clear channel assessment (CCA) detects a busy channel. In doing so they may neglect the implicit information of the failed CCA detection and further cause the redundant sensing. The blind backoff process in the slotted CSMA/CA will cause lower channel utilization. This paper proposes an additional carrier sensing (ACS) algorithm based on IEEE 802.15.4 to enhance the carrier sensing mechanism for the original slotted CSMA/CA. An analytical Markov chain model is developed to evaluate the performance of the ACS algorithm. Both analytical and simulation results show that the proposed algorithm performs better than IEEE 802.15.4, which in turn significantly improves throughput, average medium access control (MAC) delay and power consumption of CCA detection.

  16. Self-Coexistence among IEEE 802.22 Networks: Distributed Allocation of Power and Channel

    Directory of Open Access Journals (Sweden)

    Sayef Azad Sakin

    2017-12-01

    Full Text Available Ensuring self-coexistence among IEEE 802.22 networks is a challenging problem owing to opportunistic access of incumbent-free radio resources by users in co-located networks. In this study, we propose a fully-distributed non-cooperative approach to ensure self-coexistence in downlink channels of IEEE 802.22 networks. We formulate the self-coexistence problem as a mixed-integer non-linear optimization problem for maximizing the network data rate, which is an NP-hard one. This work explores a sub-optimal solution by dividing the optimization problem into downlink channel allocation and power assignment sub-problems. Considering fairness, quality of service and minimum interference for customer-premises-equipment, we also develop a greedy algorithm for channel allocation and a non-cooperative game-theoretic framework for near-optimal power allocation. The base stations of networks are treated as players in a game, where they try to increase spectrum utilization by controlling power and reaching a Nash equilibrium point. We further develop a utility function for the game to increase the data rate by minimizing the transmission power and, subsequently, the interference from neighboring networks. A theoretical proof of the uniqueness and existence of the Nash equilibrium has been presented. Performance improvements in terms of data-rate with a degree of fairness compared to a cooperative branch-and-bound-based algorithm and a non-cooperative greedy approach have been shown through simulation studies.

  17. Self-Coexistence among IEEE 802.22 Networks: Distributed Allocation of Power and Channel.

    Science.gov (United States)

    Sakin, Sayef Azad; Razzaque, Md Abdur; Hassan, Mohammad Mehedi; Alamri, Atif; Tran, Nguyen H; Fortino, Giancarlo

    2017-12-07

    Ensuring self-coexistence among IEEE 802.22 networks is a challenging problem owing to opportunistic access of incumbent-free radio resources by users in co-located networks. In this study, we propose a fully-distributed non-cooperative approach to ensure self-coexistence in downlink channels of IEEE 802.22 networks. We formulate the self-coexistence problem as a mixed-integer non-linear optimization problem for maximizing the network data rate, which is an NP-hard one. This work explores a sub-optimal solution by dividing the optimization problem into downlink channel allocation and power assignment sub-problems. Considering fairness, quality of service and minimum interference for customer-premises-equipment, we also develop a greedy algorithm for channel allocation and a non-cooperative game-theoretic framework for near-optimal power allocation. The base stations of networks are treated as players in a game, where they try to increase spectrum utilization by controlling power and reaching a Nash equilibrium point. We further develop a utility function for the game to increase the data rate by minimizing the transmission power and, subsequently, the interference from neighboring networks. A theoretical proof of the uniqueness and existence of the Nash equilibrium has been presented. Performance improvements in terms of data-rate with a degree of fairness compared to a cooperative branch-and-bound-based algorithm and a non-cooperative greedy approach have been shown through simulation studies.

  18. Segmentized Clear Channel Assessment for IEEE 802.15.4 Networks.

    Science.gov (United States)

    Son, Kyou Jung; Hong, Sung Hyeuck; Moon, Seong-Pil; Chang, Tae Gyu; Cho, Hanjin

    2016-06-03

    This paper proposed segmentized clear channel assessment (CCA) which increases the performance of IEEE 802.15.4 networks by improving carrier sense multiple access with collision avoidance (CSMA/CA). Improving CSMA/CA is important because the low-power consumption feature and throughput performance of IEEE 802.15.4 are greatly affected by CSMA/CA behavior. To improve the performance of CSMA/CA, this paper focused on increasing the chance to transmit a packet by assessing precise channel status. The previous method used in CCA, which is employed by CSMA/CA, assesses the channel by measuring the energy level of the channel. However, this method shows limited channel assessing behavior, which comes from simple threshold dependent channel busy evaluation. The proposed method solves this limited channel decision problem by dividing CCA into two groups. Two groups of CCA compare their energy levels to get precise channel status. To evaluate the performance of the segmentized CCA method, a Markov chain model has been developed. The validation of analytic results is confirmed by comparing them with simulation results. Additionally, simulation results show the proposed method is improving a maximum 8.76% of throughput and decreasing a maximum 3.9% of the average number of CCAs per packet transmission than the IEEE 802.15.4 CCA method.

  19. Segmentized Clear Channel Assessment for IEEE 802.15.4 Networks

    Directory of Open Access Journals (Sweden)

    Kyou Jung Son

    2016-06-01

    Full Text Available This paper proposed segmentized clear channel assessment (CCA which increases the performance of IEEE 802.15.4 networks by improving carrier sense multiple access with collision avoidance (CSMA/CA. Improving CSMA/CA is important because the low-power consumption feature and throughput performance of IEEE 802.15.4 are greatly affected by CSMA/CA behavior. To improve the performance of CSMA/CA, this paper focused on increasing the chance to transmit a packet by assessing precise channel status. The previous method used in CCA, which is employed by CSMA/CA, assesses the channel by measuring the energy level of the channel. However, this method shows limited channel assessing behavior, which comes from simple threshold dependent channel busy evaluation. The proposed method solves this limited channel decision problem by dividing CCA into two groups. Two groups of CCA compare their energy levels to get precise channel status. To evaluate the performance of the segmentized CCA method, a Markov chain model has been developed. The validation of analytic results is confirmed by comparing them with simulation results. Additionally, simulation results show the proposed method is improving a maximum 8.76% of throughput and decreasing a maximum 3.9% of the average number of CCAs per packet transmission than the IEEE 802.15.4 CCA method.

  20. Strategies for Optimal MAC Parameters Tuning in IEEE 802.15.6 Wearable Wireless Sensor Networks.

    Science.gov (United States)

    Alam, Muhammad Mahtab; Ben Hamida, Elyes

    2015-09-01

    Wireless body area networks (WBAN) has penetrated immensely in revolutionizing the classical heath-care system. Recently, number of WBAN applications has emerged which introduce potential limits to existing solutions. In particular, IEEE 802.15.6 standard has provided great flexibility, provisions and capabilities to deal emerging applications. In this paper, we investigate the application-specific throughput analysis by fine-tuning the physical (PHY) and medium access control (MAC) parameters of the IEEE 802.15.6 standard. Based on PHY characterizations in narrow band, at the MAC layer, carrier sense multiple access collision avoidance (CSMA/CA) and scheduled access protocols are extensively analyzed. It is concluded that, IEEE 802.15.6 standard can satisfy most of the WBANs applications throughput requirements by maximum achieving 680 Kbps. However, those emerging applications which require high quality audio or video transmissions, standard is not able to meet their constraints. Moreover, delay, energy efficiency and successful packet reception are considered as key performance metrics for comparing the MAC protocols. CSMA/CA protocol provides the best results to meet the delay constraints of medical and non-medical WBAN applications. Whereas, the scheduled access approach, performs very well both in energy efficiency and packet reception ratio.

  1. Synchronous ethernet and IEEE 1588 in telecoms next generation synchronization networks

    CERN Document Server

    2013-01-01

    This book addresses the multiple technical aspects of the distribution of synchronization in new generation telecommunication networks, focusing in particular on synchronous Ethernet and IEEE1588 technologies. Many packet network engineers struggle with understanding the challenges that precise synchronization distribution can impose on networks. The usual “why”, “when” and particularly “how” can cause problems for many engineers. In parallel to this, some other markets have identical synchronization requirements, but with their own design requirements, generating further questions. This book attempts to respond to the different questions by providing background technical information. Invaluable information on state of-the-art packet network synchronization and timing architectures is provided, as well as an unbiased view on the synchronization technologies that have been internationally standardized over recent years, with the aim of providing the average reader (who is not skilled in the art) wi...

  2. Experimental video signals distribution MMF network based on IEEE 802.11 standard

    Science.gov (United States)

    Kowalczyk, Marcin; Maksymiuk, Lukasz; Siuzdak, Jerzy

    2014-11-01

    The article was focused on presentation the achievements in a scope of experimental research on transmission of digital video streams in the frame of specially realized for this purpose ROF (Radio over Fiber) network. Its construction was based on the merge of wireless IEEE 802.11 network, popularly referred as Wi-Fi, with a passive optical network PON based on multimode fibers MMF. The proposed approach can constitute interesting proposal in area of solutions in the scope of the systems monitoring extensive, within which is required covering of a large area with ensuring of a relatively high degree of immunity on the interferences transmitted signals from video IP cameras to the monitoring center and a high configuration flexibility (easily change the deployment of cameras) of such network.

  3. Intimate Transactions: The Evolution of an Ecosophical Networked Practice

    Directory of Open Access Journals (Sweden)

    Keith Armstrong

    2005-01-01

    Full Text Available Intimate Transactions is a networked interactive installation for two participants located in different geographical locations. During a 30-minute, one-on-one session they individually and collaboratively explore a range of virtual, interactive environments mediated by digital image, sound and haptic feedback. This major work evolved from a single site, non-networked version to a multi-site, server-driven artwork that operates in mixed online/offline modes. In 2005, the work was awarded an Honorary Mention in the Prix Ars Electronica and began an international tour of several high profile festivals and arts’ venues. Intimate Transactions is a product of the Transmute Collective (http://www.intimatetransactions.com.Intimate Transactions networked inter-relational design was inspired by a range of conditions, discourses and practices drawn from scientific and critical ecologies, new media and innovative performance that I collectively name ‘ecosophical praxis’. An inherent part of this approach involves the continual development of contextualizing questions, which in turn mould the work’s practice and presentation. This paper considers the issues and implications of applying this approach during the Intimate Transactions project. The concluding questions are relevant as a guiding method for othercreative practitioners similarly interested in eco-social and eco-political engagement.

  4. Automated Measurement and Signaling Systems for the Transactional Network

    Energy Technology Data Exchange (ETDEWEB)

    Piette, Mary Ann; Brown, Richard; Price, Phillip; Page, Janie; Granderson, Jessica; Riess, David; Czarnecki, Stephen; Ghatikar, Girish; Lanzisera, Steven

    2013-12-31

    The Transactional Network Project is a multi-lab activity funded by the US Department of Energy?s Building Technologies Office. The project team included staff from Lawrence Berkeley National Laboratory, Pacific Northwest National Laboratory and Oak Ridge National Laboratory. The team designed, prototyped and tested a transactional network (TN) platform to support energy, operational and financial transactions between any networked entities (equipment, organizations, buildings, grid, etc.). PNNL was responsible for the development of the TN platform, with agents for this platform developed by each of the three labs. LBNL contributed applications to measure the whole-building electric load response to various changes in building operations, particularly energy efficiency improvements and demand response events. We also provide a demand response signaling agent and an agent for cost savings analysis. LBNL and PNNL demonstrated actual transactions between packaged rooftop units and the electric grid using the platform and selected agents. This document describes the agents and applications developed by the LBNL team, and associated tests of the applications.

  5. Energy Consumption Model and Measurement Results for Network Coding-enabled IEEE 802.11 Meshed Wireless Networks

    DEFF Research Database (Denmark)

    Paramanathan, Achuthan; Rasmussen, Ulrik Wilken; Hundebøll, Martin

    2012-01-01

    This paper presents an energy model and energy measurements for network coding enabled wireless meshed networks based on IEEE 802.11 technology. The energy model and the energy measurement testbed is limited to a simple Alice and Bob scenario. For this toy scenario we compare the energy usages...... a flexible, low cost tool to be able to measure at any given node in a meshed network. We verify the precision of our tool by comparing it to a sophisticated device. Our main results in this paper are the derivation of an analytical energy model, the implementation of a distributed energy measurement testbed...

  6. Traffic Rules in Electronic Financial Transactions (EFT Networks

    Directory of Open Access Journals (Sweden)

    Vedran Batoš

    2002-01-01

    Full Text Available This paper presents the traffic rules in the EFT (ElectronicFinancial Transactions networks, based on the implementationof the solution called Gold-Net developed and implementedby Euronet Worldwide Inc. Following the traffic rulesin EFT networks, out of its worldwide experience, Gold-Netevolved a comprehensive and expandable EFT network solutiondesigned to meet an institution's needs today and in the future.It is an ITM (Integrated Transaction Management solution,modular and expandable, and consists of a comprehensiveEFT software modules with ATM and POS driving capabilities.The combination of ATM management and the onlineconnection form the intercept processing control module. Asthe marketplace grows, this solution ensures that an ente1prisemay position itself for future growth and expanded service offerings.

  7. Performance Analysis of the IEEE 802.11p Multichannel MAC Protocol in Vehicular Ad Hoc Networks.

    Science.gov (United States)

    Song, Caixia

    2017-12-12

    Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. The safety applications require timely and reliable transmissions, while the non-safety applications require efficient and high throughput. In the IEEE 1609.4 protocol, operating interval is divided into alternating Control Channel (CCH) interval and Service Channel (SCH) interval with an identical length. During the CCH interval, nodes transmit safety-related messages and control messages, and Enhanced Distributed Channel Access (EDCA) mechanism is employed to allow four Access Categories (ACs) within a station with different priorities according to their criticality for the vehicle's safety. During the SCH interval, the non-safety massages are transmitted. An analytical model is proposed in this paper to evaluate performance, reliability and efficiency of the IEEE 802.11p and IEEE 1609.4 protocols. The proposed model improves the existing work by taking serval aspects and the character of multichannel switching into design consideration. Extensive performance evaluations based on analysis and simulation help to validate the accuracy of the proposed model and analyze the capabilities and limitations of the IEEE 802.11p and IEEE 1609.4 protocols, and enhancement suggestions are given.

  8. Performance Analysis of the IEEE 802.11p Multichannel MAC Protocol in Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Caixia Song

    2017-12-01

    Full Text Available Vehicular Ad Hoc Networks (VANETs employ multichannel to provide a variety of safety and non-safety applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. The safety applications require timely and reliable transmissions, while the non-safety applications require efficient and high throughput. In the IEEE 1609.4 protocol, operating interval is divided into alternating Control Channel (CCH interval and Service Channel (SCH interval with an identical length. During the CCH interval, nodes transmit safety-related messages and control messages, and Enhanced Distributed Channel Access (EDCA mechanism is employed to allow four Access Categories (ACs within a station with different priorities according to their criticality for the vehicle’s safety. During the SCH interval, the non-safety massages are transmitted. An analytical model is proposed in this paper to evaluate performance, reliability and efficiency of the IEEE 802.11p and IEEE 1609.4 protocols. The proposed model improves the existing work by taking serval aspects and the character of multichannel switching into design consideration. Extensive performance evaluations based on analysis and simulation help to validate the accuracy of the proposed model and analyze the capabilities and limitations of the IEEE 802.11p and IEEE 1609.4 protocols, and enhancement suggestions are given.

  9. An empirical evaluation of bufferbloat in IEEE 802.11n wireless networks

    KAUST Repository

    Showail, Ahmad

    2014-04-06

    In this paper, we analyze the impact of large, persistently-full buffers (`bufferbloat\\') on various network dynamics in IEEE 802.11n wireless networks. Bufferbloat has mostly been studied in the context of wired networks. We study the impact of bufferbloat on a variety of wireless network topologies, including wireless LAN (WLAN) and multi-hop wireless networks. Our results show that a single FTP transfer between two Linux wireless hosts can saturate the buffers in the network stack, leading to RTT delays exceeding 4.5 s in multi-hop configurations. We show that well-designed Aggregate MAC Protocol Data Unit (A-MPDU) MAC-layer frame aggregation can reduce RTT delays while simultaneously increasing network throughput. However, additional measures may still be required to meet the constraints of real-time flows (such as VoIP). Our experiments show that large buffers can deteriorate the fairness in rate allocation in parking lot based multi-hop networks.

  10. Spectrum-efficient multi-channel design for coexisting IEEE 802.15.4 networks: A stochastic geometry approach

    KAUST Repository

    Elsawy, Hesham

    2014-07-01

    For networks with random topologies (e.g., wireless ad-hoc and sensor networks) and dynamically varying channel gains, choosing the long term operating parameters that optimize the network performance metrics is very challenging. In this paper, we use stochastic geometry analysis to develop a novel framework to design spectrum-efficient multi-channel random wireless networks based on the IEEE 802.15.4 standard. The proposed framework maximizes both spatial and time domain frequency utilization under channel gain uncertainties to minimize the number of frequency channels required to accommodate a certain population of coexisting IEEE 802.15.4 networks. The performance metrics are the outage probability and the self admission failure probability. We relax the single channel assumption that has been used traditionally in the stochastic geometry analysis. We show that the intensity of the admitted networks does not increase linearly with the number of channels and the rate of increase of the intensity of the admitted networks decreases with the number of channels. By using graph theory, we obtain the minimum required number of channels to accommodate a certain intensity of coexisting networks under a self admission failure probability constraint. To this end, we design a superframe structure for the coexisting IEEE 802.15.4 networks and a method for time-domain interference alignment. © 2002-2012 IEEE.

  11. Efficient Beacon Collision Resolution Procedure for IEEE 802.15.4 /Zigbee Wireless Personal Area Networks

    Directory of Open Access Journals (Sweden)

    Bassam A. Zafar

    2017-04-01

    Full Text Available While IEEE 802.15.4/Zigbee is a promising technology for Wireless Personal Area Networks, several transmission problems are not yet resolved. In particular, the problem of beacon transmission interferences is causing the device connection loss to the network. In order to resolve this problem, we present a new distributed and reactive procedure for beacon collision resolution. It is an extension of the alignment procedure to reorganize randomly the beacon transmission time when a collision has occurred. The detail of the proposed procedure will be fully described and analyzed. The performance of our approach is performed by simulations. The results show that our approach reduces the collision probability and the device disconnections consequently.

  12. On the Feasibility of Wireless Multimedia Sensor Networks over IEEE 802.15.5 Mesh Topologies.

    Science.gov (United States)

    Garcia-Sanchez, Antonio-Javier; Losilla, Fernando; Rodenas-Herraiz, David; Cruz-Martinez, Felipe; Garcia-Sanchez, Felipe

    2016-05-05

    Wireless Multimedia Sensor Networks (WMSNs) are a special type of Wireless Sensor Network (WSN) where large amounts of multimedia data are transmitted over networks composed of low power devices. Hierarchical routing protocols typically used in WSNs for multi-path communication tend to overload nodes located within radio communication range of the data collection unit or data sink. The battery life of these nodes is therefore reduced considerably, requiring frequent battery replacement work to extend the operational life of the WSN system. In a wireless sensor network with mesh topology, any node may act as a forwarder node, thereby enabling multiple routing paths toward any other node or collection unit. In addition, mesh topologies have proven advantages, such as data transmission reliability, network robustness against node failures, and potential reduction in energy consumption. This work studies the feasibility of implementing WMSNs in mesh topologies and their limitations by means of exhaustive computer simulation experiments. To this end, a module developed for the Synchronous Energy Saving (SES) mode of the IEEE 802.15.5 mesh standard has been integrated with multimedia tools to thoroughly test video sequences encoded using H.264 in mesh networks.

  13. BOB-RED queue management for IEEE 802.15.4 wireless sensor networks

    Directory of Open Access Journals (Sweden)

    Wu Jean-Lien

    2011-01-01

    Full Text Available Abstract Multimedia services over resource constrained wireless sensor networks (WSNs face a performance bottleneck issue from the gateway node to the sink node. Therefore, the queue management at the gateway node is crucial for diversified messages conveyed from the front nodes to the sink node. In this article, beacon order-based random early detection (BOB-RED queue management is proposed. BOB-RED is a dynamic adaptation scheme based on adjusting beacon interval and superframe duration in the IEEE 802.15.4 MAC superframe accompanied with RED queue management scheme to increase the transmission efficiency of multimedia over WSNs. We focus on the performance improvement upon different traffic loads over WSNs. Evaluation metrics include end-to-end delay, packet delivery ratio, and energy consumption in IEEE 802.15.4 beacon enabled mode. Simulation results show that BOB-RED can effectively decrease end-to-end delay and energy consumption compared to the DropTail scheme.

  14. Packetizing OCP Transactions in the MANGO Network-on-Chip

    DEFF Research Database (Denmark)

    Bjerregaard, Tobias; Sparsø, Jens

    2006-01-01

    The scaling of CMOS technology causes a widening gap between the performance of on-chip communication and computation. This calls for a communication-centric design flow. The MANGO network-on-chip architecture enables globally asynchronous locally synchronous (GALS) system-on-chip design, while...... transactions are packetized and transmitted across the shared network, and illustrate how this affects the end-to-end performance. A high predictability of the latency of communication on shared links is shown in a MANGO-based demonstrator system...

  15. Delay efficient cooperation in public safety vehicular networks using LTE and IEEE 802.11p

    KAUST Repository

    Atat, Rachad

    2012-01-01

    Cooperative schemes for critical content distribution over vehicular networks are presented and analyzed. The first scheme is based on unicasting from the base station, whereas the second is based on threshold based multicasting. Long Term Evolution (LTE) is used for long range communications with the base station (BS) and 802.11p is considered for inter-vehicle collaboration on the short range. A high mobility environment with correlated shadowing is adopted. Both schemes are shown to outperform non-cooperative unicasting and multicasting, respectively, when the appropriate 802.11p power class is used. The first scheme achieves the best performance among the compared methods, and a practical approximation of that scheme is shown to be close to optimal performance. © 2012 IEEE.

  16. A study of IEEE 802.15.4 security framework for wireless body area networks.

    Science.gov (United States)

    Saleem, Shahnaz; Ullah, Sana; Kwak, Kyung Sup

    2011-01-01

    A Wireless Body Area Network (WBAN) is a collection of low-power and lightweight wireless sensor nodes that are used to monitor the human body functions and the surrounding environment. It supports a number of innovative and interesting applications, including ubiquitous healthcare and Consumer Electronics (CE) applications. Since WBAN nodes are used to collect sensitive (life-critical) information and may operate in hostile environments, they require strict security mechanisms to prevent malicious interaction with the system. In this paper, we first highlight major security requirements and Denial of Service (DoS) attacks in WBAN at Physical, Medium Access Control (MAC), Network, and Transport layers. Then we discuss the IEEE 802.15.4 security framework and identify the security vulnerabilities and major attacks in the context of WBAN. Different types of attacks on the Contention Access Period (CAP) and Contention Free Period (CFP) parts of the superframe are analyzed and discussed. It is observed that a smart attacker can successfully corrupt an increasing number of GTS slots in the CFP period and can considerably affect the Quality of Service (QoS) in WBAN (since most of the data is carried in CFP period). As we increase the number of smart attackers the corrupted GTS slots are eventually increased, which prevents the legitimate nodes to utilize the bandwidth efficiently. This means that the direct adaptation of IEEE 802.15.4 security framework for WBAN is not totally secure for certain WBAN applications. New solutions are required to integrate high level security in WBAN.

  17. A Study of IEEE 802.15.4 Security Framework for Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Kyung Sup Kwak

    2011-01-01

    Full Text Available A Wireless Body Area Network (WBAN is a collection of low-power and lightweight wireless sensor nodes that are used to monitor the human body functions and the surrounding environment. It supports a number of innovative and interesting applications, including ubiquitous healthcare and Consumer Electronics (CE applications. Since WBAN nodes are used to collect sensitive (life-critical information and may operate in hostile environments, they require strict security mechanisms to prevent malicious interaction with the system. In this paper, we first highlight major security requirements and Denial of Service (DoS attacks in WBAN at Physical, Medium Access Control (MAC, Network, and Transport layers. Then we discuss the IEEE 802.15.4 security framework and identify the security vulnerabilities and major attacks in the context of WBAN. Different types of attacks on the Contention Access Period (CAP and Contention Free Period (CFP parts of the superframe are analyzed and discussed. It is observed that a smart attacker can successfully corrupt an increasing number of GTS slots in the CFP period and can considerably affect the Quality of Service (QoS in WBAN (since most of the data is carried in CFP period. As we increase the number of smart attackers the corrupted GTS slots are eventually increased, which prevents the legitimate nodes to utilize the bandwidth efficiently. This means that the direct adaptation of IEEE 802.15.4 security framework for WBAN is not totally secure for certain WBAN applications. New solutions are required to integrate high level security in WBAN.

  18. Measuring the Influence of Networks on Transaction Costs Using a Nonparametric Regression Technique

    DEFF Research Database (Denmark)

    Henningsen, Geraldine; Henningsen, Arne; Henning, Christian H.C.A.

    All business transactions as well as achieving innovations take up resources, subsumed under the concept of transaction costs. One of the major factors in transaction costs theory is information. Firm networks can catalyse the interpersonal information exchange and hence, increase the access to n...

  19. The Performance Evaluation of an IEEE 802.11 Network Containing Misbehavior Nodes under Different Backoff Algorithms

    Directory of Open Access Journals (Sweden)

    Trong-Minh Hoang

    2017-01-01

    Full Text Available Security of any wireless network is always an important issue due to its serious impacts on network performance. Practically, the IEEE 802.11 medium access control can be violated by several native or smart attacks that result in downgrading network performance. In recent years, there are several studies using analytical model to analyze medium access control (MAC layer misbehavior issue to explore this problem but they have focused on binary exponential backoff only. Moreover, a practical condition such as the freezing backoff issue is not included in the previous models. Hence, this paper presents a novel analytical model of the IEEE 802.11 MAC to thoroughly understand impacts of misbehaving node on network throughput and delay parameters. Particularly, the model can express detailed backoff algorithms so that the evaluation of the network performance under some typical attacks through numerical simulation results would be easy.

  20. Packet size optimization for goodput and energy efficiency enhancement in slotted IEEE 802.15.4 networks

    NARCIS (Netherlands)

    Zhang, Y.; Shu, F.

    2009-01-01

    To address system goodput and energy efficiency enhancement, this paper studies packet size optimization for IEEE 802.15.4 networks. Taking into account of the CSMA-CA contention, protocol overhead, and channel condition, new analytical models are proposed to calculate the goodput and the energy

  1. Mathematical modeling of a radio-frequency path for IEEE 802.11ah based wireless sensor networks

    Science.gov (United States)

    Tyshchenko, Igor; Cherepanov, Alexander; Dmitrii, Vakhnin; Popova, Mariia

    2017-09-01

    This article discusses the process of creating the mathematical model of a radio-frequency path for an IEEE 802.11ah based wireless sensor networks using M atLab Simulink CAD tools. In addition, it describes occurring perturbing effects and determining the presence of a useful signal in the received mixture.

  2. IEEE 802.11 Networks: A Simple Model Geared Towards Offloading Studies and Considerations on Future Small Cells

    DEFF Research Database (Denmark)

    Garcia, Luis Guilherme Uzeda; Rodriguez, Ignacio; Catania, Davide

    2013-01-01

    WiFi is the prevalent wireless access technology in local area deployments and is expected to play a major role in a mobile operator’s data offloading strategy. As a result, having simple tools that are able to assess the offloading potential of IEEE 802.11 networks is vital. In this paper, we...

  3. Link Investigation of IEEE 802.15.4 Wireless Sensor Networks in Forests

    Science.gov (United States)

    Ding, Xingjian; Sun, Guodong; Yang, Gaoxiang; Shang, Xinna

    2016-01-01

    Wireless sensor networks are expected to automatically monitor the ecological evolution and wildlife habits in forests. Low-power links (transceivers) are often adopted in wireless sensor network applications, in order to save the precious sensor energy and then achieve long-term, unattended monitoring. Recent research has presented some performance characteristics of such low-power wireless links under laboratory or outdoor scenarios with less obstacles, and they have found that low-power wireless links are unreliable and prone to be affected by the target environment. However, there is still less understanding about how well the low-power wireless link performs in real-world forests and to what extent the complex in-forest surrounding environments affect the link performances. In this paper, we empirically evaluate the low-power links of wireless sensors in three typical different forest environments. Our experiment investigates the performance of the link layer compatible with the IEEE 802.15.4 standard and analyzes the variation patterns of the packet reception ratio (PRR), the received signal strength indicator (RSSI) and the link quality indicator (LQI) under diverse experimental settings. Some observations of this study are inconsistent with or even contradict prior results that are achieved in open fields or relatively clean environments and thus, provide new insights both into effectively evaluating the low-power wireless links and into efficiently deploying wireless sensor network systems in forest environments. PMID:27355957

  4. Link Investigation of IEEE 802.15.4 Wireless Sensor Networks in Forests.

    Science.gov (United States)

    Ding, Xingjian; Sun, Guodong; Yang, Gaoxiang; Shang, Xinna

    2016-06-27

    Wireless sensor networks are expected to automatically monitor the ecological evolution and wildlife habits in forests. Low-power links (transceivers) are often adopted in wireless sensor network applications, in order to save the precious sensor energy and then achieve long-term, unattended monitoring. Recent research has presented some performance characteristics of such low-power wireless links under laboratory or outdoor scenarios with less obstacles, and they have found that low-power wireless links are unreliable and prone to be affected by the target environment. However, there is still less understanding about how well the low-power wireless link performs in real-world forests and to what extent the complex in-forest surrounding environments affect the link performances. In this paper, we empirically evaluate the low-power links of wireless sensors in three typical different forest environments. Our experiment investigates the performance of the link layer compatible with the IEEE 802.15.4 standard and analyzes the variation patterns of the packet reception ratio (PRR), the received signal strength indicator (RSSI) and the link quality indicator (LQI) under diverse experimental settings. Some observations of this study are inconsistent with or even contradict prior results that are achieved in open fields or relatively clean environments and thus, provide new insights both into effectively evaluating the low-power wireless links and into efficiently deploying wireless sensor network systems in forest environments.

  5. On the Network Convergence Process in RPL over IEEE 802.15.4 Multihop Networks: Improvement and Trade-Offs

    Directory of Open Access Journals (Sweden)

    Hamidreza Kermajani

    2014-07-01

    Full Text Available The IPv6 Routing Protocol for Low-power and Lossy Networks (RPL has been recently developed by the Internet Engineering Task Force (IETF. Given its crucial role in enabling the Internet of Things, a significant amount of research effort has already been devoted to RPL. However, the RPL network convergence process has not yet been investigated in detail. In this paper we study the influence of the main RPL parameters and mechanisms on the network convergence process of this protocol in IEEE 802.15.4 multihop networks. We also propose and evaluate a mechanism that leverages an option available in RPL for accelerating the network convergence process. We carry out extensive simulations for a wide range of conditions, considering different network scenarios in terms of size and density. Results show that network convergence performance depends dramatically on the use and adequate configuration of key RPL parameters and mechanisms. The findings and contributions of this work provide a RPL configuration guideline for network convergence performance tuning, as well as a characterization of the related performance trade-offs.

  6. On the network convergence process in RPL over IEEE 802.15.4 multihop networks: improvement and trade-offs.

    Science.gov (United States)

    Kermajani, Hamidreza; Gomez, Carles

    2014-07-07

    The IPv6 Routing Protocol for Low-power and Lossy Networks (RPL) has been recently developed by the Internet Engineering Task Force (IETF). Given its crucial role in enabling the Internet of Things, a significant amount of research effort has already been devoted to RPL. However, the RPL network convergence process has not yet been investigated in detail. In this paper we study the influence of the main RPL parameters and mechanisms on the network convergence process of this protocol in IEEE 802.15.4 multihop networks. We also propose and evaluate a mechanism that leverages an option available in RPL for accelerating the network convergence process. We carry out extensive simulations for a wide range of conditions, considering different network scenarios in terms of size and density. Results show that network convergence performance depends dramatically on the use and adequate configuration of key RPL parameters and mechanisms. The findings and contributions of this work provide a RPL configuration guideline for network convergence performance tuning, as well as a characterization of the related performance trade-offs.

  7. Green Frame Aggregation Scheme for IEEE 802.11n Networks

    KAUST Repository

    Alaslani, Maha S.

    2015-04-01

    Frame aggregation is one of the major MAC layer enhancements in the IEEE 802.11 family that boosts the network throughput performance. It aims to achieve higher throughput by transmitting huge amount of data in a single transmit oppor- tunity. With the increasing awareness of energy e ciency, it has become vital to rethink about the design of such frame aggregation protocol. Aggregation techniques help to reduce energy consumption over ideal channel conditions. However, in a noisy channel environment, a new energy-aware frame aggregation scheme is required. In this thesis, a novel Green Frame Aggregation (GFA) scheduling scheme has been proposed and evaluated. GFA optimizes the aggregate size based on channel quality in order to minimize the consumed energy. GFA selects the optimal sub-frame size that satisfies the loss constraint for real-time applications as well as the energy budget of the ideal channel situations. The design, the implementation, and evaluation of GFA using testbed deployment is done. The experimental analysis shows that GFA outperforms the conventional frame aggregation methodology in terms of energy e ciency by about 6⇥ in the presence of severe interference conditions. Moreover, GFA also outperforms the static frame sizing method in terms of network goodput and maintains almost the same end- to-end latency.

  8. Achievable Throughput-Based MAC Layer Handoff in IEEE 802.11 Wireless Local Area Networks

    Directory of Open Access Journals (Sweden)

    Wu Haitao

    2009-01-01

    Full Text Available We propose a MAC layer handoff mechanism for IEEE 802.11 Wireless Local Area Networks (WLAN to give benefit to bandwidth-greedy applications at STAs. The proposed mechanism determines an optimal AP with the maximum achievable throughput rather than the best signal condition by estimating the AP's bandwidth with a new on-the-fly measurement method, Transient Frame Capture (TFC, and predicting the actual throughput could be achieved at STAs. Since the TFC is employed based on the promiscuous mode of WLAN NIC, STAs can avoid the service degradation through the current associated AP. In addition, the proposed mechanism is a client-only solution which does not require any modification of network protocol on APs. To evaluate the performance of the proposed mechanism, we develop an analytic model to estimate reliable and accurate bandwidth of the AP and demonstrate through testbed measurement with various experimental study methods. We also validate the fairness of the proposed mechanism through simulation studies.

  9. Experimental Performance Evaluation of Multihop IEEE 802.15.4/4g/4e Smart Utility Networks in Outdoor Environment

    Directory of Open Access Journals (Sweden)

    Chin-Sean Sum

    2017-01-01

    Full Text Available This paper presents the experimental performance evaluation results of the IEEE 802.15.4/4g/4e Smart Utility Networks (SUN in applications suited for outdoor environment. SUN is an advanced wireless communications network designed for reliable, low data rate, and low energy consumption networks for command-and-control applications like utility service, sensor network, and so on. IEEE 802.15.4g/4e is the international standard for SUN supported by multiple utility providers and product vendors. In this paper, a comprehensive field test was conducted by employing the implementation we have developed to evaluate the performance of the SUN devices based on IEEE 802.15.4/4g/4e standard. The output power of the implementation is 250 mW for extended range, reducible to 20 mW for short-range scalability and battery preservation. Results showed that in an outdoor line-of-sight environment, the achievable one-hop range of a 50 kbps SUN device was 450 m. Next, in a non-line-of-sight environment involving typical residential concrete building, the communications could be established penetrating obstructions to reach above the 11th storey, reaching the performance degradation limits at the 20th storey. Next, the network of the SUN system was proven to be capable of supporting a typical multihop tree network in a dense populated building, meeting the required performance by the standard.

  10. Optimizing the MAC Protocol in Localization Systems Based on IEEE 802.15.4 Networks.

    Science.gov (United States)

    Pérez-Solano, Juan J; Claver, Jose M; Ezpeleta, Santiago

    2017-07-06

    Radio frequency signals are commonly used in the development of indoor localization systems. The infrastructure of these systems includes some beacons placed at known positions that exchange radio packets with users to be located. When the system is implemented using wireless sensor networks, the wireless transceivers integrated in the network motes are usually based on the IEEE 802.15.4 standard. But, the CSMA-CA, which is the basis for the medium access protocols in this category of communication systems, is not suitable when several users want to exchange bursts of radio packets with the same beacon to acquire the radio signal strength indicator (RSSI) values needed in the location process. Therefore, new protocols are necessary to avoid the packet collisions that appear when multiple users try to communicate with the same beacons. On the other hand, the RSSI sampling process should be carried out very quickly because some systems cannot tolerate a large delay in the location process. This is even more important when the RSSI sampling process includes measures with different signal power levels or frequency channels. The principal objective of this work is to speed up the RSSI sampling process in indoor localization systems. To achieve this objective, the main contribution is the proposal of a new MAC protocol that eliminates the medium access contention periods and decreases the number of packet collisions to accelerate the RSSI collection process. Moreover, the protocol increases the overall network throughput taking advantage of the frequency channel diversity. The presented results show the suitability of this protocol for reducing the RSSI gathering delay and increasing the network throughput in simulated and real environments.

  11. Optimizing the MAC Protocol in Localization Systems Based on IEEE 802.15.4 Networks

    Directory of Open Access Journals (Sweden)

    Juan J. Pérez-Solano

    2017-07-01

    Full Text Available Radio frequency signals are commonly used in the development of indoor localization systems. The infrastructure of these systems includes some beacons placed at known positions that exchange radio packets with users to be located. When the system is implemented using wireless sensor networks, the wireless transceivers integrated in the network motes are usually based on the IEEE 802.15.4 standard. But, the CSMA-CA, which is the basis for the medium access protocols in this category of communication systems, is not suitable when several users want to exchange bursts of radio packets with the same beacon to acquire the radio signal strength indicator (RSSI values needed in the location process. Therefore, new protocols are necessary to avoid the packet collisions that appear when multiple users try to communicate with the same beacons. On the other hand, the RSSI sampling process should be carried out very quickly because some systems cannot tolerate a large delay in the location process. This is even more important when the RSSI sampling process includes measures with different signal power levels or frequency channels. The principal objective of this work is to speed up the RSSI sampling process in indoor localization systems. To achieve this objective, the main contribution is the proposal of a new MAC protocol that eliminates the medium access contention periods and decreases the number of packet collisions to accelerate the RSSI collection process. Moreover, the protocol increases the overall network throughput taking advantage of the frequency channel diversity. The presented results show the suitability of this protocol for reducing the RSSI gathering delay and increasing the network throughput in simulated and real environments.

  12. Scheduling strategies and throughput optimization for the Downlink for IEEE 802.11ax and IEEE 802.11ac based networks

    OpenAIRE

    Sharon, Oran; Alpert, Yaron

    2017-01-01

    The new IEEE 802.11 standard, IEEE 802.11ax, has the challenging goal of serving more users compared to its predecessor IEEE 802.11ac, enabling consistent and reliable streams of data (average throughput) per station. In this paper we explore some of the IEEE 802.11ax new mechanisms and compare between the upper bounds on the throughputs of the Downlink unidirectional UDP Multi Users (MU) triadic based on Multiple-Input-Multiple-Output (MU-MIMO) and Orthogonal Frequency Division Multiple Acce...

  13. Performance Evaluation of IEEE 802.11ah Networks With High-Throughput Bidirectional Traffic.

    Science.gov (United States)

    Šljivo, Amina; Kerkhove, Dwight; Tian, Le; Famaey, Jeroen; Munteanu, Adrian; Moerman, Ingrid; Hoebeke, Jeroen; De Poorter, Eli

    2018-01-23

    So far, existing sub-GHz wireless communication technologies focused on low-bandwidth, long-range communication with large numbers of constrained devices. Although these characteristics are fine for many Internet of Things (IoT) applications, more demanding application requirements could not be met and legacy Internet technologies such as Transmission Control Protocol/Internet Protocol (TCP/IP) could not be used. This has changed with the advent of the new IEEE 802.11ah Wi-Fi standard, which is much more suitable for reliable bidirectional communication and high-throughput applications over a wide area (up to 1 km). The standard offers great possibilities for network performance optimization through a number of physical- and link-layer configurable features. However, given that the optimal configuration parameters depend on traffic patterns, the standard does not dictate how to determine them. Such a large number of configuration options can lead to sub-optimal or even incorrect configurations. Therefore, we investigated how two key mechanisms, Restricted Access Window (RAW) grouping and Traffic Indication Map (TIM) segmentation, influence scalability, throughput, latency and energy efficiency in the presence of bidirectional TCP/IP traffic. We considered both high-throughput video streaming traffic and large-scale reliable sensing traffic and investigated TCP behavior in both scenarios when the link layer introduces long delays. This article presents the relations between attainable throughput per station and attainable number of stations, as well as the influence of RAW, TIM and TCP parameters on both. We found that up to 20 continuously streaming IP-cameras can be reliably connected via IEEE 802.11ah with a maximum average data rate of 160 kbps, whereas 10 IP-cameras can achieve average data rates of up to 255 kbps over 200 m. Up to 6960 stations transmitting every 60 s can be connected over 1 km with no lost packets. The presented results enable the fine tuning

  14. A Collaborative Network Model for Agrifood Transactions on Regional Base

    Science.gov (United States)

    Volpentesta, Antonio P.; Ammirato, Salvatore

    The paper deals with a collaborative agrifood network in a regional scenario where producers of high typical and quality goods and consumer groups are involved in agrifood transactions as well as information and knowledge exchanges through an e-business platform. While producers are engaged in providing consumers with useful and timely information about healthiness, environmentally friendliness and most importantly, food quality of their products, consumers are engaged in giving prompt and understandable feedbacks to the producers. In this sense, the network is a form of proactive learning community. Starting from some basic socio-economic assumptions on a reference territory, we present an organizational model that can be adopted to foster the development of the regional area where it is applied. An instantiation of the model for a selected territory (the District of High Quality Productions in Sibari, Calabria, Italy) and first results, coming from two pilot tests, have been summarized as well.

  15. Do the rich get richer? An empirical analysis of the BitCoin transaction network

    CERN Document Server

    Kondor, Dániel; Csabai, István; Vattay, Gábor

    2013-01-01

    The possibility to analyze everyday monetary transactions is limited by the scarcity of available data, as this kind of information is usually considered highly sensitive. Present econophysics models are usually employed on presumed random networks of interacting agents, and only macroscopic properties (e.g. the resulting wealth distribution) are compared to real-world data. In this paper, we analyze BitCoin, which is a novel digital currency system, where the complete list of transactions is publicly available. Using this dataset, we reconstruct the network of transactions, and extract the time and amount of each payment. We analyze the structure of the transaction network by measuring network characteristics over time, such as the degree distribution, degree correlations and clustering. We find that linear preferential attachment drives the growth of the network. We also study the dynamics taking place on the transaction network, i.e. the flow of money. We measure temporal patterns and the wealth accumulati...

  16. Design of zone-based bandwidth management scheme in IEEE 802.16 multi-hop relay networks

    Directory of Open Access Journals (Sweden)

    Chen Kuo-Yang

    2011-01-01

    Full Text Available Abstract IEEE 802.16 Wireless Network technology is a hot research issue in recent years. It provides wider coverage of radio and higher speed wireless access, and Quality-of-Service plays an important part in the standard. For mobile multi-hop wireless network, IEEE 802.16j/MR network not only can supply large area wireless deployment, but also can provide high quality network service to mobile users. Although Mobile QoS supporting has been extensively investigated, Mobile QoS supporting in the IEEE 802.16-MR network is relatively unexplored. In this article, the probability of a mobile user who visits a Relay Station (RS is known beforehand. With the visiting probability at each RS and the system specified size of the range for bandwidth allocation, Base Station (BS can calculate the required bandwidth to meet the mobile user's demand and allocate appropriate bandwidth for a mobile user roaming in the range of the bandwidth allocation. The range of bandwidth allocation for mobile users is called the Zone in this article, which includes the user's current RS and the nearby RSs. The proposed scheme is therefore called Zone-based bandwidth management scheme. The simulation results demonstrate that Zone-based bandwidth management scheme can reduce QoS degradation and bandwidth re-allocation overhead.

  17. IEEE Transactions on Professional Communication

    DEFF Research Database (Denmark)

    2008-01-01

    , the theory and practice of technical communication in Europe, Asia, South America, and other places deserve closer attention. Substantial differences between the state of the discipline in North America and abroad impact our work in this globalized world, as well as our current students' future professional...... practice. For example, technical communication theory and practice in the U.S. typically emerge from Rhetoric and Writing Studies as well as from Communication Studies. Competence in multiple languages is usually not required for obtaining a degree or working in the field. In contrast, in Western Europe......, technical communication as a discipline is heavily influenced by the theory and practice of translation and language for specific purposes due to the multilingual and multicultural nature of the space in which technical communicators operate. Similarly, in countries like Ukraine and Russia, instruction...

  18. Compliance and Functional Testing of IEEE 1451.1 for NCAP-to-NCAP Communications in a Sensor Network

    Science.gov (United States)

    Figueroa, Jorge; Gurkan, Deniz; Yuan, X.; Benhaddou, D.; Liu, H.; Singla, A.; Franzl, R.; Ma, H.; Bhatt, S.; Morris, J.; hide

    2008-01-01

    Distributed control in a networked environment is an irreplaceable feature in systems with remote sensors and actuators. Although distributed control was not originally designed to be networked, usage of off-the-shelf networking technologies has become so prevalent that control systems are desired to have access mechanisms similar to computer networks. However, proprietary transducer interfaces for network communications and distributed control overwhelmingly dominate this industry. Unless the lack of compatibility and interoperability among transducers is resolved, the mature level of access (that computer networking can deliver) will not be achieved in such networked distributed control systems. Standardization of networked transducer interfaces will enable devices from different manufacturers to talk to each other and ensure their plug-and-play capability. One such standard is the suite of IEEE 1451 for sensor network communication and transducer interfaces. The suite not only provides a standard interface for smart transducers, but also outlines the connection of an NCAP (network capable application processor) and transducers (through a transducer interface module TIM). This paper presents the design of the compliance testing of IEEE 1451.1 (referred to as Dot1) compatible NCAP-to-NCAP communications on a link-layer independent medium. The paper also represents the first demonstration of NCAP-to-NCAP communications with Dot1 compatibility: a tester NCAP and an NCAP under test (NUT).

  19. An Enhanced Reservation-Based MAC Protocol for IEEE 802.15.4 Networks

    Science.gov (United States)

    Afonso, José A.; Silva, Helder D.; Macedo, Pedro; Rocha, Luis A.

    2011-01-01

    The IEEE 802.15.4 Medium Access Control (MAC) protocol is an enabling standard for wireless sensor networks. In order to support applications requiring dedicated bandwidth or bounded delay, it provides a reservation-based scheme named Guaranteed Time Slot (GTS). However, the GTS scheme presents some drawbacks, such as inefficient bandwidth utilization and support to a maximum of only seven devices. This paper presents eLPRT (enhanced Low Power Real Time), a new reservation-based MAC protocol that introduces several performance enhancing features in comparison to the GTS scheme. This MAC protocol builds on top of LPRT (Low Power Real Time) and includes various mechanisms designed to increase data transmission reliability against channel errors, improve bandwidth utilization and increase the number of supported devices. A motion capture system based on inertial and magnetic sensors has been used to validate the protocol. The effectiveness of the performance enhancements introduced by each of the new features is demonstrated through the provision of both simulation and experimental results. PMID:22163826

  20. Service Differentiation in OFDM-Based IEEE 802.16 Networks

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available IEEE 802.16 network is widely viewed as a strong candidate solution for broadband wireless access systems. Various flexible mechanisms related to QoS provisioning have been specified for uplink traffic at the medium access control (MAC layer in the standards. Among the mechanisms, bandwidth request scheme can be used to indicate and request bandwidth demands to the base station for different services. Due to the diverse QoS requirements of the applications, service differentiation (SD is desirable for the bandwidth request scheme. In this paper, we propose several SD approaches. The approaches are based on the contention-based bandwidth request scheme and achieved by the means of assigning different channel access parameters and/or bandwidth allocation priorities to different services. Additionally, we propose effective analytical model to study the impacts of the SD approaches, which can be used for the configuration and optimization of the SD services. It is observed from simulations that the analytical model has high accuracy. Service can be efficiently differentiated with initial backoff window in terms of throughput and channel access delay. Moreover, the service differentiation can be improved if combined with the bandwidth allocation priority approach without adverse impacts on the overall system throughput.

  1. An Enhanced Reservation-Based MAC Protocol for IEEE 802.15.4 Networks

    Directory of Open Access Journals (Sweden)

    Luis A. Rocha

    2011-03-01

    Full Text Available The IEEE 802.15.4 Medium Access Control (MAC protocol is an enabling standard for wireless sensor networks. In order to support applications requiring dedicated bandwidth or bounded delay, it provides a reservation-based scheme named Guaranteed Time Slot (GTS. However, the GTS scheme presents some drawbacks, such as inefficient bandwidth utilization and support to a maximum of only seven devices. This paper presents eLPRT (enhanced Low Power Real Time, a new reservation-based MAC protocol that introduces several performance enhancing features in comparison to the GTS scheme. This MAC protocol builds on top of LPRT (Low Power Real Time and includes various mechanisms designed to increase data transmission reliability against channel errors, improve bandwidth utilization and increase the number of supported devices. A motion capture system based on inertial and magnetic sensors has been used to validate the protocol. The effectiveness of the performance enhancements introduced by each of the new features is demonstrated through the provision of both simulation and experimental results.

  2. Energy Harvesting - Wireless Sensor Networks for Indoors Applications Using IEEE 802.11

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon; Sørensen, Thomas; Madsen, Jan

    2014-01-01

    The paper investigates the feasibility of using IEEE 802.11 in energy harvesting low-power sensing applications. The investigation is based on a prototype carbon dioxide sensor node that is powered by artificial indoors light. The wireless communication module of the sensor node is based on the RTX......4100 module. RTX4100 incorporates a wireless protocol that duty-cycles the radio while being compatible with IEEE 802.11 access points. The presented experiments demonstrate sustainable operation but indicate a trade-off between the benefits of using IEEE 802.11 in energy harvesting applications...

  3. Research on e-commerce transaction networks using multi-agent modelling and open application programming interface

    Science.gov (United States)

    Piao, Chunhui; Han, Xufang; Wu, Harris

    2010-08-01

    We provide a formal definition of an e-commerce transaction network. Agent-based modelling is used to simulate e-commerce transaction networks. For real-world analysis, we studied the open application programming interfaces (APIs) from eBay and Taobao e-commerce websites and captured real transaction data. Pajek is used to visualise the agent relationships in the transaction network. We derived one-mode networks from the transaction network and analysed them using degree and betweenness centrality. Integrating multi-agent modelling, open APIs and social network analysis, we propose a new way to study large-scale e-commerce systems.

  4. Design of handoff procedures for broadband wireless access IEEE 802.16 based networks

    Directory of Open Access Journals (Sweden)

    V. Rangel–Licea

    2008-01-01

    Full Text Available IEEE 802.16 is a protocol for fixed broad band wire less access that is currently trying to add mobility among mobile users in the standard. However, mobility adds some technical barriers that should be solved first, this is the case of HO "handoff" (change of connection between two base stations "BS" by a mobile user. In this paper, the problem of HO in IEEE 802.16 is approached try ing to maintain the quality of service (QoS of mobile users. A mechanism for changing connection during HO is pre sented. A simulation model based on OPNET MODELER1 was developed to evaluate the performance of the proposed HO mechanism. Finally, this paper demonstrates that it is possible to implement a seam less HO mech a nism over IEEE 802.16 even for users with de manding applications such as voice over IP.

  5. Adaptive Ranging Code Allocation Scheme in IEEE 802.16 Networks

    Directory of Open Access Journals (Sweden)

    Chu Kuo-Chih

    2010-01-01

    Full Text Available IEEE 802.16 uses the code division multiple access (CDMA method as the channel access method to decrease the collision probability of data delivery. However, IEEE 802.16 does not regulate a ranging code allocation scheme in its specification. In this paper, we propose the adaptive ranging code allocation (ARCA scheme, a novel ranging code allocation scheme for IEEE 802.16. According to the traffic sent to the base station (BS from the mobile station (MS, the ARCA scheme not only forecasts the traffic quantity of the MS but also finds the optimal ranging code allocation value for the MS to improve the transmission success rate next time. The ARCA scheme is verified with simulation and compared with other schemes in performance differences. According to the simulation results, the ARCA scheme is proved to have better performance than other schemes.

  6. Dynamic subframe allocation for mobile broadband m-health using IEEE 802.16j mobile multihop relay networks.

    Science.gov (United States)

    Alinejad, Ali; Istepanian, R S H; Philip, N

    2012-01-01

    The concept of 4G health will be one of the key focus areas of future m-health research and enterprise activities in the coming years. WiMAX technology is one of the constituent 4G wireless technologies that provides broadband wireless access (BWA). Despite the fact that WiMAX is able to provide a high data rate in a relatively large coverage; this technology has specific limitations such as: coverage, signal attenuation problems due to shadowing or path loss, and limited available spectrum. The IEEE 802.16j mobile multihop relay (MMR) technology is a pragmatic solution designed to overcome these limitations. The aim of IEEE 802.16j MMR is to expand the IEEE 802.16e's capabilities with multihop features. In particular, the uplink (UL) and downlink (DL) subframe allocation in WiMAX network is usually fixed. However, dynamic frame allocation is a useful mechanism to optimize uplink and downlink subframe size dynamically based on the traffic conditions through real-time traffic monitoring. This particular mechanism is important for future WiMAX based m-health applications as it allows the tradeoff in both UL and DL channels. In this paper, we address the dynamic frame allocation issue in IEEE 802.16j MMR network for m-health applications. A comparative performance analysis of the proposed approach is validated using the OPNET Modeler(®). The simulation results have shown an improved performance of resource allocation and end-to-end delay performance for typical medical video streaming application.

  7. Performance modeling of a two-tier primary-secondary network with IEEE 802.11 broadcast scheme

    KAUST Repository

    Khabazian, Mehdi

    2011-03-01

    In this paper, we study the performance of a two-tier primary-secondary network based on IEEE 802.11 broadcast scheme. We assume that a number of primary and secondary users coexist in the radio environment and share a single band. To protect the primary users\\' priority, the secondary users are allowed to contend for the channel only if they sense it idle for a certain sensing time. Considering an exponential packet inter-arrival time for the primary network, we model each primary user as an independent M/G/1 queue. Subsequently, we determine the primary users\\' average medium access delay in the presence of secondary users as well as the hybrid network\\'s throughput. Numerical results and discussions show the effects of parameters pertaining to the secondary users, such as as sensing time, packet payload size and population size, on the performance of the primary network. Furthermore, we provide simulation results which confirm the accuracy of the proposed analysis. © 2011 IEEE.

  8. An Authentication and Key Management Mechanism for Resource Constrained Devices in IEEE 802.11-based IoT Access Networks

    Directory of Open Access Journals (Sweden)

    Ki-Wook Kim

    2017-09-01

    Full Text Available Many Internet of Things (IoT services utilize an IoT access network to connect small devices with remote servers. They can share an access network with standard communication technology, such as IEEE 802.11ah. However, an authentication and key management (AKM mechanism for resource constrained IoT devices using IEEE 802.11ah has not been proposed as yet. We therefore propose a new AKM mechanism for an IoT access network, which is based on IEEE 802.11 key management with the IEEE 802.1X authentication mechanism. The proposed AKM mechanism does not require any pre-configured security information between the access network domain and the IoT service domain. It considers the resource constraints of IoT devices, allowing IoT devices to delegate the burden of AKM processes to a powerful agent. The agent has sufficient power to support various authentication methods for the access point, and it performs cryptographic functions for the IoT devices. Performance analysis shows that the proposed mechanism greatly reduces computation costs, network costs, and memory usage of the resource-constrained IoT device as compared to the existing IEEE 802.11 Key Management with the IEEE 802.1X authentication mechanism.

  9. An Authentication and Key Management Mechanism for Resource Constrained Devices in IEEE 802.11-based IoT Access Networks.

    Science.gov (United States)

    Kim, Ki-Wook; Han, Youn-Hee; Min, Sung-Gi

    2017-09-21

    Many Internet of Things (IoT) services utilize an IoT access network to connect small devices with remote servers. They can share an access network with standard communication technology, such as IEEE 802.11ah. However, an authentication and key management (AKM) mechanism for resource constrained IoT devices using IEEE 802.11ah has not been proposed as yet. We therefore propose a new AKM mechanism for an IoT access network, which is based on IEEE 802.11 key management with the IEEE 802.1X authentication mechanism. The proposed AKM mechanism does not require any pre-configured security information between the access network domain and the IoT service domain. It considers the resource constraints of IoT devices, allowing IoT devices to delegate the burden of AKM processes to a powerful agent. The agent has sufficient power to support various authentication methods for the access point, and it performs cryptographic functions for the IoT devices. Performance analysis shows that the proposed mechanism greatly reduces computation costs, network costs, and memory usage of the resource-constrained IoT device as compared to the existing IEEE 802.11 Key Management with the IEEE 802.1X authentication mechanism.

  10. Mathematical Analysis of EDCA's Performance on the Control Channel of an IEEE 802.11p WAVE Vehicular Network

    Directory of Open Access Journals (Sweden)

    Hussein T. Mouftah

    2010-01-01

    Full Text Available Wireless networks for vehicular environments are gaining increasing importance due to their ability to provide a means for stations on the roadside and radio units on board of vehicles to communicate and share safety-related information, thus reducing the probability of accidents and increasing the efficiency of the transportation system. With this goal in mind, the IEEE is currently developing the Wireless Access in Vehicular Environments (WAVE IEEE 802.11p standard. WAVE devices use the IEEE 802.11's Enhanced Distributed Channel Access (EDCA MAC protocol to compete for the transmission medium. This work proposes an analytical tool to evaluate the performance of EDCA under the specific conditions of the so-called control channel (CCH of a WAVE environment, including the particular EDCA parameter values and the fact that all safety-critical data frames are broadcasted. The protocol is modeled using Markov chains and results related to throughput, frame-error rate, buffer occupancy and delay are obtained under different traffic-load conditions. The main analysis is performed assuming that the CCH works continuously, and then an explanation is given as to the considerations that are needed to account for the fact that activity on the CCH is intermittent.

  11. Design of Cyberwar Laboratory Exercises to Implement Common Security Attacks against IEEE 802.11 Wireless Networks

    Directory of Open Access Journals (Sweden)

    Mina Malekzadeh

    2010-01-01

    Full Text Available In wireless network communications, radio waves travel through free space; hence, the information reaches any receiving point with appropriate radio receivers. This aspect makes the wireless networks vulnerable to various types of attacks. A true understanding of these attacks provides better ability to defend the network against the attacks, thus eliminating potential threats from the wireless systems. This work presents a series of cyberwar laboratory exercises that are designed for IEEE 802.11 wireless networks security courses. The exercises expose different aspects of violations in security such as confidentiality, privacy, availability, and integrity. The types of attacks include traffic analysis, rogue access point, MAC filtering, replay, man-in-the-middle, and denial of service attacks. For each exercise, the materials are presented as open-source tools along with descriptions of the respective methods, procedures, and penetration techniques.

  12. Uplink capacity of multi-class IEEE 802.16j relay networks with adaptive modulation and coding

    DEFF Research Database (Denmark)

    Wang, Hua; Xiong, C; Iversen, Villy Bæk

    2009-01-01

    The emerging IEEE 802.16j mobile multi-hop relay (MMR) network is currently being developed to increase the user throughput and extend the service coverage as an enhancement of existing 802.16e standard. In 802.16j, the intermediate relay stations (RSs) help the base station (BS) communicate...... with those mobile stations (MSs) that are either too far away from the BS or placed in an area where direct communication with BS experiences unsatisfactory level of service. In this paper, we investigate the uplink Erlang capacity of a two-hop 802.16j relay system supporting both voice and data traffics...

  13. 15th IEEE/ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing

    CERN Document Server

    2015-01-01

    This edited book presents scientific results of 15th IEEE/ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing (SNPD 2014) held on June 30 – July 2, 2014 in Las Vegas Nevada, USA. The aim of this conference was to bring together scientists, engineers, computer users, and students to share their experiences and exchange new ideas, research results about all aspects (theory, applications and tools) of computer and information science, and to discuss the practical challenges encountered along the way and the solutions adopted to solve them. The conference organizers selected the 13 outstanding papers from those papers accepted for presentation at the conference.

  14. 14th ACIS/IEEE International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing

    CERN Document Server

    Studies in Computational Intelligence : Volume 492

    2013-01-01

    This edited book presents scientific results of the 14th ACIS/IEEE International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing (SNPD 2013), held in Honolulu, Hawaii, USA on July 1-3, 2013. The aim of this conference was to bring together scientists, engineers, computer users, and students to share their experiences and exchange new ideas, research results about all aspects (theory, applications and tools) of computer and information science, and to discuss the practical challenges encountered along the way and the solutions adopted to solve them. The conference organizers selected the 17 outstanding papers from those papers accepted for presentation at the conference.  

  15. Performance analysis of IEEE 802.11n network under unsaturated conditions

    Science.gov (United States)

    Lang, Gaiping; Ma, Lin; Xu, Yubin

    2017-07-01

    Frame aggregation is the most important medium access control (MAC) enhancement of IEEE 802.11n. In frame aggregation, multiple frames are encapsulated into a single frame. In the analysis of 802.11n performance, the existing researches assumed that each station always had a packet for transmission. But actually, sometimes stations may have no packet to transmit. In this paper, we develop an analytical model for IEEE 802.11n in unsaturated conditions. Therefore, the transmission of the station is assumed to be a bulk service queue system. Bulk size is aggregation size. According to the 802.11n standard, when the number of packets in the buffer is smaller than the aggregation size, we can also transmit all the packets in the buffer using A-MPDU. Therefore, bulk size is variable. The throughput and mean access delay are achieved. Numerical results show that the proposed algorithm can effectively increase the throughput and lower the access delay.

  16. Optimal modulation and coding scheme allocation of scalable video multicast over IEEE 802.16e networks

    Directory of Open Access Journals (Sweden)

    Tsai Chia-Tai

    2011-01-01

    Full Text Available Abstract With the rapid development of wireless communication technology and the rapid increase in demand for network bandwidth, IEEE 802.16e is an emerging network technique that has been deployed in many metropolises. In addition to the features of high data rate and large coverage, it also enables scalable video multicasting, which is a potentially promising application, over an IEEE 802.16e network. How to optimally assign the modulation and coding scheme (MCS of the scalable video stream for the mobile subscriber stations to improve spectral efficiency and maximize utility is a crucial task. We formulate this MCS assignment problem as an optimization problem, called the total utility maximization problem (TUMP. This article transforms the TUMP into a precedence constraint knapsack problem, which is a NP-complete problem. Then, a branch and bound method, which is based on two dominance rules and a lower bound, is presented to solve the TUMP. The simulation results show that the proposed branch and bound method can find the optimal solution efficiently.

  17. Improving the communication reliability of body sensor networks based on the IEEE 802.15.4 protocol.

    Science.gov (United States)

    Gomes, Diogo; Afonso, José A

    2014-03-01

    Body sensor networks (BSNs) enable continuous monitoring of patients anywhere, with minimum constraints to daily life activities. Although the IEEE 802.15.4 and ZigBee(®) (ZigBee Alliance, San Ramon, CA) standards were mainly developed for use in wireless sensors network (WSN) applications, they are also widely used in BSN applications because of device characteristics such as low power, low cost, and small form factor. However, compared with WSNs, BSNs present some very distinctive characteristics in terms of traffic and mobility patterns, heterogeneity of the nodes, and quality of service requirements. This article evaluates the suitability of the carrier sense multiple access-collision avoidance protocol, used by the IEEE 802.15.4 and ZigBee standards, for data-intensive BSN applications, through the execution of experimental tests in different evaluation scenarios, in order to take into account the effects of contention, clock drift, and hidden nodes on the communication reliability. Results show that the delivery ratio may decrease substantially during transitory periods, which can last for several minutes, to a minimum of 90% with retransmissions and 13% without retransmissions. This article also proposes and evaluates the performance of the BSN contention avoidance mechanism, which was designed to solve the identified reliability problems. This mechanism was able to restore the delivery ratio to 100% even in the scenario without retransmissions.

  18. Adaptive Transmission Opportunity Scheme Based on Delay Bound and Network Load in IEEE 802.11e Wireless LANs

    Directory of Open Access Journals (Sweden)

    S. Kim

    2013-08-01

    Full Text Available The IEEE 802.11e EDCA (Enhanced Distributed Channel Access is able to provide QoS (Quality of Service by adjusting the transmission opportunities (TXOPs, which control the period to access the medium. The EDCA has a fairness problem among competing stations, which support multimedia applications with different delay bounds. In this paper, we propose a simple and effective scheme for alleviating the fairness problem. The proposed scheme dynamically allocates the TXOP value based on the delay bounds of the data packets in a queue and the traffic load of network. Performance of the proposed scheme is investigated by simulation. Our results show that compared to conventional scheme, the proposed scheme significantly improves network performance, and achieves a high degree of fairness among stations with different multimedia applications.

  19. POLLING AND DUAL-LEVEL TRAFFIC ANALYSIS FOR IMPROVED DOS DETECTION IN IEEE 802.21 NETWORKS

    Directory of Open Access Journals (Sweden)

    Nygil Alex Vadakkan

    2014-06-01

    Full Text Available The IEEE 802.21 standard was developed for communication of devices in a heterogeneous environment which included greater support for handoffs. This paper focuses on the denial of service (DoS vulnerabilities faced by such Media Independent Handover (MIH networks & various effective countermeasures that can be deployed to prevent their impact on such heterogeneous networks. The use of polling mechanism coupled with real time as well as offline traffic analysis can keep a good number of attacks at bay. The use of offline traffic analysis is to use the model and compare it with a lighter model and see if any of the excluded features in the lighter model have had suspicious variations which could be a varied form of DoS attack or an attack that is completely new. The countermeasures that have been developed also allows for the increase in efficiency of data transfer as well as higher rates of success in handoffs.

  20. A PROPOSED NOVEL ARCHITECTURE OF EC CONTROL SYSTEM USING IEEE 802.11n NETWORK AT ITER-INDIA GYROTRON TEST FACILITY

    Directory of Open Access Journals (Sweden)

    Deepak Mandge

    2017-06-01

    Full Text Available IEEE 802.11 Wi-Fi networks are increasingly becoming popular for its use in industrial applications. With the availability of recent amendments to IEEE 802.11 series of standards, particularly IEEE 802.11n, the adoption of Wi-Fi networks for process automation is gaining more focus and importance. The installation of Wireless networks naturally provides reduction in cable and its maintenance related costs, provides increased flexibility and mobility to enhance performance of industrial control system. The IEEE 802.11n supports parameterization that can be set for particular industrial applications and hence it has addressed to the aspects of timeliness and criticality to some extent. This paper proposes the use of IEEE 802.11n network to interconnect field instruments with Siemens PLC controller in harsh EMI/EMC environment. An application example is shown where the alternate control system architecture is developed in which non-critical and non-safety signals are communicated over Wi-Fi. While, for critical and safety signals, traditional hardwired signals methods can be implemented.

  1. Do the rich get richer? An empirical analysis of the Bitcoin transaction network.

    Directory of Open Access Journals (Sweden)

    Dániel Kondor

    Full Text Available The possibility to analyze everyday monetary transactions is limited by the scarcity of available data, as this kind of information is usually considered highly sensitive. Present econophysics models are usually employed on presumed random networks of interacting agents, and only some macroscopic properties (e.g. the resulting wealth distribution are compared to real-world data. In this paper, we analyze Bitcoin, which is a novel digital currency system, where the complete list of transactions is publicly available. Using this dataset, we reconstruct the network of transactions and extract the time and amount of each payment. We analyze the structure of the transaction network by measuring network characteristics over time, such as the degree distribution, degree correlations and clustering. We find that linear preferential attachment drives the growth of the network. We also study the dynamics taking place on the transaction network, i.e. the flow of money. We measure temporal patterns and the wealth accumulation. Investigating the microscopic statistics of money movement, we find that sublinear preferential attachment governs the evolution of the wealth distribution. We report a scaling law between the degree and wealth associated to individual nodes.

  2. Do the Rich Get Richer? An Empirical Analysis of the Bitcoin Transaction Network

    Science.gov (United States)

    Kondor, Dániel; Pósfai, Márton; Csabai, István; Vattay, Gábor

    2014-01-01

    The possibility to analyze everyday monetary transactions is limited by the scarcity of available data, as this kind of information is usually considered highly sensitive. Present econophysics models are usually employed on presumed random networks of interacting agents, and only some macroscopic properties (e.g. the resulting wealth distribution) are compared to real-world data. In this paper, we analyze Bitcoin, which is a novel digital currency system, where the complete list of transactions is publicly available. Using this dataset, we reconstruct the network of transactions and extract the time and amount of each payment. We analyze the structure of the transaction network by measuring network characteristics over time, such as the degree distribution, degree correlations and clustering. We find that linear preferential attachment drives the growth of the network. We also study the dynamics taking place on the transaction network, i.e. the flow of money. We measure temporal patterns and the wealth accumulation. Investigating the microscopic statistics of money movement, we find that sublinear preferential attachment governs the evolution of the wealth distribution. We report a scaling law between the degree and wealth associated to individual nodes. PMID:24505257

  3. Do the rich get richer? An empirical analysis of the Bitcoin transaction network.

    Science.gov (United States)

    Kondor, Dániel; Pósfai, Márton; Csabai, István; Vattay, Gábor

    2014-01-01

    The possibility to analyze everyday monetary transactions is limited by the scarcity of available data, as this kind of information is usually considered highly sensitive. Present econophysics models are usually employed on presumed random networks of interacting agents, and only some macroscopic properties (e.g. the resulting wealth distribution) are compared to real-world data. In this paper, we analyze Bitcoin, which is a novel digital currency system, where the complete list of transactions is publicly available. Using this dataset, we reconstruct the network of transactions and extract the time and amount of each payment. We analyze the structure of the transaction network by measuring network characteristics over time, such as the degree distribution, degree correlations and clustering. We find that linear preferential attachment drives the growth of the network. We also study the dynamics taking place on the transaction network, i.e. the flow of money. We measure temporal patterns and the wealth accumulation. Investigating the microscopic statistics of money movement, we find that sublinear preferential attachment governs the evolution of the wealth distribution. We report a scaling law between the degree and wealth associated to individual nodes.

  4. A Green Media Access Method for IEEE 802.15.6 Wireless Body Area Network.

    Science.gov (United States)

    Jacob, Anil K; Jacob, Lillykutty

    2017-09-30

    It is of utmost importance to conserve battery energy to the maximum possible extent in WBAN nodes while collecting and transferring medical data. The IEEE 802.15.6 WBAN standard does not specify any method to conserve energy. This paper focuses on a method to conserve energy in IEEE 802.15.6 WBAN nodes when using CSMA/CA, while simultaneously restricting data delivery delay to the required value as specified in medical applications. The technique is to allow the nodes to sleep all the times except for receiving beacons and for transmitting data frames whenever a data frame enters an empty buffer. The energy consumed by the nodes and the average latency of data frame for periodical arrival of data are found out analytically. The analytical results are validated and also the proposed method is compared with other energy conserving schemes, using Castalia simulation studies. The proposed method shows superior performance in both device lifetime and latency of emergency medical data.

  5. Group-Orthogonal Code-Division Multiplex: A Physical-Layer Enhancement for IEEE 802.11n Networks

    Directory of Open Access Journals (Sweden)

    Felip Riera-Palou

    2010-01-01

    Full Text Available The new standard for wireless local area networks (WLANs, named IEEE 802.11n, has been recently released. This new norm builds upon and remains compatible with the previous WLANs standards IEEE 802.11a/g while it is able to achieve transmission rates of up to 600 Mbps. These increased data rates are mainly a consequence of two important new features: (1 multiple antenna technology at transmission and reception, and (2 optional doubling of the system bandwidth thanks to the availability of an additional 20 MHz band. This paper proposes the use of Group-Orthogonal Code Division Multiplex (GO-CDM as a means to improve the performance of the 802.11n standard by further exploiting the inherent frequency diversity. It is explained why GO-CDM synergistically matches with the two aforementioned new features and the performance gains it can offer under different configurations is illustrated. Furthermore, the effects that group-orthogonal has on key implementation issues such as channel estimation, carrier frequency offset, and peak-to-average power ratio (PAPR are also considered.

  6. Simple Adaptive Single Differential Coherence Detection of BPSK Signals in IEEE 802.15.4 Wireless Sensor Networks.

    Science.gov (United States)

    Zhang, Gaoyuan; Wen, Hong; Wang, Longye; Xie, Ping; Song, Liang; Tang, Jie; Liao, Runfa

    2017-12-26

    In this paper, we propose an adaptive single differential coherent detection (SDCD) scheme for the binary phase shift keying (BPSK) signals in IEEE 802.15.4 Wireless Sensor Networks (WSNs). In particular, the residual carrier frequency offset effect (CFOE) for differential detection is adaptively estimated, with only linear operation, according to the changing channel conditions. It was found that the carrier frequency offset (CFO) and chip signal-to-noise ratio (SNR) conditions do not need a priori knowledge. This partly benefits from that the combination of the trigonometric approximation sin - 1 ( x ) ≈ x and a useful assumption, namely, the asymptotic or high chip SNR, is considered for simplification of the full estimation scheme. Simulation results demonstrate that the proposed algorithm can achieve an accurate estimation and the detection performance can completely meet the requirement of the IEEE 802.15.4 standard, although with a little loss of reliability and robustness as compared with the conventional optimal single-symbol detector.

  7. 17th IEEE/ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing

    CERN Document Server

    SNPD 2016

    2016-01-01

    This edited book presents scientific results of the 17th IEEE/ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing (SNPD 2016) which was held on May 30 - June 1, 2016 in Shanghai, China. The aim of this conference was to bring together researchers and scientists, businessmen and entrepreneurs, teachers, engineers, computer users, and students to discuss the numerous fields of computer science and to share their experiences and exchange new ideas and information in a meaningful way. Research results about all aspects (theory, applications and tools) of computer and information science, and to discuss the practical challenges encountered along the way and the solutions adopted to solve them.

  8. 6th IEEE/ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing

    CERN Document Server

    2016-01-01

    This edited book presents scientific results of the 16th IEEE/ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing (SNPD 2015) which was held on June 1 – 3, 2015 in Takamatsu, Japan. The aim of this conference was to bring together researchers and scientists, businessmen and entrepreneurs, teachers, engineers, computer users, and students to discuss the numerous fields of computer science and to share their experiences and exchange new ideas and information in a meaningful way. Research results about all aspects (theory, applications and tools) of computer and information science, and to discuss the practical challenges encountered along the way and the solutions adopted to solve them.

  9. Network Constrained Transactive Control for Electric Vehicles Integration

    DEFF Research Database (Denmark)

    Hu, Junjie; Yang, Guangya; Bindner, Henrik W.

    2015-01-01

    actors are considered: distribution system operator (DSO), fleet operators and EV owners. In the lower level of the hierarchy, the fleet operator centrally manages the charging schedule of electric vehicles; in the upper level of the hierarchy, the DSO uses transactive control technique to coordinate......Electric vehicles (EVs) are commonly recognized as smart grid assets in addition to their environmental benefits. However, uncoordinated charging or sole cost minimization based charging of electric vehicles may bring undesirable peak demands and voltage violations in the distribution system....... This paper applies the transactive control concept to integrate electric vehicles into the power distribution system with the purpose of minimizing the charging cost of electric vehicles as well as preventing grid congestions and voltage violations. A hierarchical EV management system is proposed where three...

  10. New IEEE 11073 Standards for interoperable, networked Point-of-Care Medical Devices.

    Science.gov (United States)

    Kasparick, Martin; Schlichting, Stefan; Golatowski, Frank; Timmermann, Dirk

    2015-08-01

    Surgical procedures become more and more complex and the number of medical devices in an operating room (OR) increases continuously. Today's vendor-dependent solutions for integrated ORs are not able to handle this complexity. They can only form isolated solutions. Furthermore, high costs are a result of vendor-dependent approaches. Thus we present a service-oriented device communication for distributed medical systems that enables the integration and interconnection between medical devices among each other and to (medical) information systems, including plug-and-play functionality. This system will improve patient's safety by making technical complexity of a comprehensive integration manageable. It will be available as open standards that are part of the IEEE 11073 family of standards. The solution consists of a service-oriented communication technology, the so called Medical Devices Profile for Web Services (MDPWS), a Domain Information & Service Model, and a binding between the first two mechanisms. A proof of this concept has been done with demonstrators of real world OR devices.

  11. Adaptive QoS provision for IEEE 802.16e BWA networks based on cross-layer design

    Directory of Open Access Journals (Sweden)

    Kuo GS

    2011-01-01

    Full Text Available Abstract This article proposes an integrated framework for adaptive QoS provision in IEEE 802.16e broadband wireless access networks based on cross-layer design. On one hand, an efficient admission control (AC algorithm is proposed along with a semi-reservation scheme to guarantee the connection-level QoS. First, to guarantee the service continuity for handoff connections and resource efficiency, our semi-reservation scheme considers both users' handoff probability and average resource consumption together, which effectively avoids resource over-reservation and insufficient reservation. For AC, a new/handoff connection is accepted only when the target cell has enough resource to afford both instantaneous and average resource consumption to meet the average source rate request. On the other hand, a joint resource allocation and packet scheduling scheme is designed to provide packet-level QoS guarantee in term of "QoS rate", which can ensure fairness for the services with identical priority level in case of bandwidth shortage. Particularly, an enhanced bandwidth request scheme is designed to reduce unnecessary BR delay and redundant signaling overhead caused by the existing one in IEEE 802.16e, which further improves the packet-level QoS performance and resource efficiency for uplink transmission. Simulation results show that the proposed approach not only balances the tradeoff among connection blocking rate, connection dropping rate, and connection failure rate, but also achieves low mean packet dropping rate (PDR, small deviation of PDR, and low QoS outage rate. Moreover, high resource efficiency is ensured.

  12. Energy optimization based path selection algorithm for IEEE 802.11s wireless mesh networks

    CSIR Research Space (South Africa)

    Mhlanga, MM

    2011-09-01

    Full Text Available It is everyone’s dream to have network connectivity anywhere at all times. This dream can only be realized provided there are feasible solutions that are put in place for the next generation of wireless works. Wireless Mesh Networks (WMNs...

  13. Fuzzy logic congestion control in IEEE 802.11 wireless local area networks: A performance evaluation

    CSIR Research Space (South Africa)

    Nyirenda, CN

    2007-09-01

    Full Text Available to the wireless network. Therefore, the implementation of a congestion control mechanism in Access Points promises to be a suitable solution. Recently, a particle swarm optimized Fuzzy Logic Congestion Detection (FLCD) was proposed for IP networks. This algorithm...

  14. Wireless Computational Networking Architectures

    Science.gov (United States)

    2013-12-01

    2] T. Ho, M. Medard, R. Kotter , D. Karger, M. Effros, J. Shi, and B. Leong, “A Random Linear Network Coding Approach to Multicast,” IEEE...218, January 2008. [10] R. Kotter and F. R. Kschischang, “Coding for Errors and Erasures in Random Network Coding,” IEEE Transactions on...Systems, Johns Hopkins University, Baltimore, Maryland, 2011. 6. B. W. Suter and Z. Yan U.S. Patent Pending 13/949,319 Rank Deficient Decoding

  15. WQM: An Aggregation-aware Queue Management Scheme for IEEE 802.11n based Networks

    KAUST Repository

    Showail, Ahmad

    2014-08-17

    Choosing the right buffer size in Wi-Fi networks is challenging due to the dynamic nature of the wireless environment. Over buffering or \\'bufferbloat\\' may produce unacceptable end-to-end delays, while static small buffers may limit the performance gains that can be achieved with various 802.11n enhancements, such as frame aggregation. We propose WQM, a queue management scheme customized for wireless networks. WQM adapts the buffer size based on measured link characteristics and network load. Furthermore, it accounts for aggregate length when deciding about the optimal buffer size. We implement WQM on Linux and evaluate it on a wireless testbed. WQM reduces the end-to-end delay by up to 8x compared to Linux default buffer size, and 2x compared to CoDel, the state-of-the-art bufferbloat solution, while achieving comparable network goodput. Further, WQM improves fairness as it limits the ability of a single flow to saturate the buffer.

  16. Analysis of User Plane in IEEE 802.11b/g QoS Networks

    Directory of Open Access Journals (Sweden)

    N. Nešković

    2010-06-01

    Full Text Available In this paper we present the performances evaluation of infrastructure 802.11b/g QoS networks, in both HCF (Hybrid Coordination Function operating modes: EDCA (Enhanced Distributed Channel Access and HCCA (HCF Controlled Channel Access. Besides comparing these two modes in terms of total network throughput (between themselves as well as against the theoretical limit, in this paper we introduce further analyses: impact of modulation scheme on the total throughput, determination of throughput for different traffic categories and average packet delivery delay.

  17. Cross-Layer Measurement on an IEEE 802.11g Wireless Network Supporting MPEG-2 Video Streaming Applications in the Presence of Interference

    Directory of Open Access Journals (Sweden)

    Alessandro Sona

    2010-01-01

    Full Text Available The performance of wireless local area networks supporting video streaming applications, based on MPEG-2 video codec, in the presence of interference is here dealt with. IEEE 802.11g standard wireless networks, that do not support QoS in according with IEEE 802.11e standard, are, in particular, accounted for and Bluetooth signals, additive white Gaussian noise, and competitive data traffic are considered as sources of interference. The goal is twofold: from one side, experimentally assessing and correlating the values that some performance metrics assume at the same time at different layers of an IEEE 802.11g WLAN delivering video streaming in the presence of in-channel interference; from the other side, deducing helpful and practical hints for designers and technicians, in order to efficiently assess and enhance the performance of an IEEE 802.11g WLAN supporting video streaming in some suitable setup conditions and in the presence of interference. To this purpose, an experimental analysis is planned following a cross-layer measurement approach, and a proper testbed within a semianechoic chamber is used. Valuable results are obtained in terms of signal-to-interference ratio, packet loss ratio, jitter, video quality, and interference data rate; helpful hints for designers and technicians are finally gained.

  18. Governance Structure, Perception, and Innovation in Credence Food Transactions: The Role of Food Community Networks

    Directory of Open Access Journals (Sweden)

    Stefano Pascucci

    2010-10-01

    Full Text Available  Promoting transactions of more sustainable-oriented foods can be (socially and privately complex and costly. New institutional economics (NIE explains these dynamics by analyzing the choice of the "most cost-economizing" governance structure to carry out a transaction where credence attributes are involved. The way different governance structures can influence the change of consumers and producers perceptions and preferences for credence foods is completely neglected. On the other hand behavioral economics underlines the role of status quo bias and framing in this type of decision making process. We use new institutional and behavioural economics arguments to conceptualize the emerging of a new governance structure in the domain of credence food transactions which we defined as food community network (FCN.

  19. IEEE 802.15.4 ZigBee-Based Time-of-Arrival Estimation for Wireless Sensor Networks.

    Science.gov (United States)

    Cheon, Jeonghyeon; Hwang, Hyunsu; Kim, Dongsun; Jung, Yunho

    2016-02-05

    Precise time-of-arrival (TOA) estimation is one of the most important techniques in RF-based positioning systems that use wireless sensor networks (WSNs). Because the accuracy of TOA estimation is proportional to the RF signal bandwidth, using broad bandwidth is the most fundamental approach for achieving higher accuracy. Hence, ultra-wide-band (UWB) systems with a bandwidth of 500 MHz are commonly used. However, wireless systems with broad bandwidth suffer from the disadvantages of high complexity and high power consumption. Therefore, it is difficult to employ such systems in various WSN applications. In this paper, we present a precise time-of-arrival (TOA) estimation algorithm using an IEEE 802.15.4 ZigBee system with a narrow bandwidth of 2 MHz. In order to overcome the lack of bandwidth, the proposed algorithm estimates the fractional TOA within the sampling interval. Simulation results show that the proposed TOA estimation algorithm provides an accuracy of 0.5 m at a signal-to-noise ratio (SNR) of 8 dB and achieves an SNR gain of 5 dB as compared with the existing algorithm. In addition, experimental results indicate that the proposed algorithm provides accurate TOA estimation in a real indoor environment.

  20. Body area networks using IEEE 802156 implementing the ultra wide band physical layer

    CERN Document Server

    Hernandez, Marco; Mucchi, Lorenzo

    2014-01-01

    The market of wearable wireless medical sensors is experiencing a rapid growth and the associated telecommunications services for the healthcare sector are forecast to further increase in the next years. Medical body area networks (MBANs) allow the mobility of patients and medical personnel by facilitating the remote monitoring of patients suffering from chronic or risky diseases. Currently, MBANs are being introduced in unlicensed frequency bands, where the risk of mutual interference with other electronic devices radiating in the same band can be high. Thus, coexistence is an issue on which

  1. Network Design for Reliability and Resilience to Attack

    Science.gov (United States)

    2014-03-01

    nuclear smuggling interdiction, IIE Transactions , vol. 39, no. 1, pp. 314, Jan. 2007. [31] L. V. Snyder, M. P. Scaparra, M. S. Daskin, and R. L. Church...complexity of network reliability analysis: An overview, IEEE Transactions on Reliability, vol. 35, no. 3, pp. 230239, Aug. 1986. [12] L. G. Valiant, The...Kanturska, J.-D. Schmöcker, and A. Fonzone, Attacker-defender models and road network vulnerability. Philosophical transactions . Series A, Math

  2. Listening to Whispers of Ripple: Linking Wallets and Deanonymizing Transactions in the Ripple Network

    Directory of Open Access Journals (Sweden)

    Moreno-Sanchez Pedro

    2016-10-01

    Full Text Available The decentralized I owe you (IOU transaction network Ripple is gaining prominence as a fast, low-cost and efficient method for performing same and cross-currency payments. Ripple keeps track of IOU credit its users have granted to their business partners or friends, and settles transactions between two connected Ripple wallets by appropriately changing credit values on the connecting paths. Similar to cryptocurrencies such as Bitcoin, while the ownership of the wallets is implicitly pseudonymous in Ripple, IOU credit links and transaction flows between wallets are publicly available in an online ledger. In this paper, we present the first thorough study that analyzes this globally visible log and characterizes the privacy issues with the current Ripple network. In particular, we define two novel heuristics and perform heuristic clustering to group wallets based on observations on the Ripple network graph. We then propose reidentification mechanisms to deanonymize the operators of those clusters and show how to reconstruct the financial activities of deanonymized Ripple wallets. Our analysis motivates the need for better privacy-preserving payment mechanisms for Ripple and characterizes the privacy challenges faced by the emerging credit networks.

  3. Economic Assessment of Network-Constrained Transactive Energy for Managing Flexible Demand in Distribution Systems

    DEFF Research Database (Denmark)

    Hu, Junjie; Yang, Guangya; Xue, Yusheng

    2017-01-01

    The increasing number of distributed energy resources such as electric vehicles and heat pumps connected to power systems raises operational challenges to the network operator, for example, introducing grid congestion and voltage deviations in the distribution network level if their operations...... are not properly coordinated. Coordination and control of a large number of distributed energy resources requires innovative approaches. In this paper, we follow up on a recently proposed network-constrained transactive energy (NCTE) method for scheduling of electric vehicles and heat pumps within a retailer...

  4. WING/WORLD: An Open Experimental Toolkit for the Design and Deployment of IEEE 802.11-Based Wireless Mesh Networks Testbeds

    Directory of Open Access Journals (Sweden)

    Daniele Miorandi

    2010-01-01

    Full Text Available Wireless Mesh Networks represent an interesting instance of light-infrastructure wireless networks. Due to their flexibility and resiliency to network failures, wireless mesh networks are particularly suitable for incremental and rapid deployments of wireless access networks in both metropolitan and rural areas. This paper illustrates the design and development of an open toolkit aimed at supporting the design of different solutions for wireless mesh networking by enabling real evaluation, validation, and demonstration. The resulting testbed is based on off-the-shelf hardware components and open-source software and is focused on IEEE 802.11 commodity devices. The software toolkit is based on an “open” philosophy and aims at providing the scientific community with a tool for effective and reproducible performance analysis of WMNs. The paper describes the architecture of the toolkit, and its core functionalities, as well as its potential evolutions.

  5. IEEE 802.15.4 MAC with GTS transmission for heterogeneous devices with application to wheelchair body-area sensor networks.

    Science.gov (United States)

    Shrestha, Bharat; Hossain, Ekram; Camorlinga, Sergio

    2011-09-01

    In wireless personal area networks, such as wireless body-area sensor networks, stations or devices have different bandwidth requirements and, thus, create heterogeneous traffics. For such networks, the IEEE 802.15.4 medium access control (MAC) can be used in the beacon-enabled mode, which supports guaranteed time slot (GTS) allocation for time-critical data transmissions. This paper presents a general discrete-time Markov chain model for the IEEE 802.15.4-based networks taking into account the slotted carrier sense multiple access with collision avoidance and GTS transmission phenomena together in the heterogeneous traffic scenario and under nonsaturated condition. For this purpose, the standard GTS allocation scheme is modified. For each non-identical device, the Markov model is solved and the average service time and the service utilization factor are analyzed in the non-saturated mode. The analysis is validated by simulations using network simulator version 2.33. Also, the model is enhanced with a wireless propagation model and the performance of the MAC is evaluated in a wheelchair body-area sensor network scenario.

  6. Networks and RegionalCompetitiveness: Towards a Transaction Cost Approach of Small-Scale Cooperation

    Directory of Open Access Journals (Sweden)

    Daniel Friel

    2005-06-01

    Full Text Available A preoccupation with competition often dominates the study of governance. A focus on competition often unnecessarily precludes the possibility that regional institutions can suspend competition in certain areas and facilitate cooperation among potential rivals, thereby potentially contributing to their mutual success. In many ways companies cooperating through these types of networks have a greater degree of flexibility than firms which are forced to rely solely on hierarchies or markets for solutions to their problems. In order to fully understand how such networks work, this article first parses out differences in definitions of networks in order to understand how the type of network mentioned above actually differs from other uses of this term. Then it develops a theory of governance that goes beyond hierarchies and markets by demonstrating how this type of network can lead to reductions in transaction costs. This claim is illustrated on hand from examples of alternative forms of organization in Germany and Italy.

  7. Resource Allocation and Cross Layer Control in Wireless Networks

    Science.gov (United States)

    2006-08-25

    Modiano , and J. Tsitsiklis, �Optimal energy allocation and admis- sion control for communication satellites,�IEEE Transactions on Networking, vol. 11...E. Modiano , �Improving delay in ad-hoc mobile networks via redundant packet transfers,�in Proceedings of Conference on Information Sciences and...M. J. Neely, E. Modiano , and C.-P. Li, �Fairness and optimal stochastic con- trol for heterogeneous networks,�in Proceedings of IEEE INFOCOM, Miami

  8. Comparison of Analytical and Measured Performance Results on Network Coding in IEEE 802.11 Ad-Hoc Networks

    DEFF Research Database (Denmark)

    Zhao, Fang; Médard, Muriel; Hundebøll, Martin

    2012-01-01

    CATWOMAN that can run on standard WiFi hardware. We present an analytical model to evaluate the performance of COPE in simple networks, and our results show the excellent predictive quality of this model. By closely examining the performance in two simple topologies, we observe that the coding gain results...

  9. TCP over IEEE 802.11

    Directory of Open Access Journals (Sweden)

    P. Chenna Reddy

    2009-01-01

    Full Text Available IEEE 802.11 is a widely used wireless LAN standard for medium access control. TCP is a prominent transport protocol originally designed for wired networks. TCP treats packet loss as congestion and reduces the data rate. In wireless networks packets are lost not only due to congestion but also due to various other reasons. Hence there is need for making TCP adaptable to wireless networks. Various parameters of TCP and IEEE 802.11 can be set to appropriate values to achieve optimum performance results. In this paper optimum values for various parameters of IEEE 802.11 are determined. Network simulator NS2 is used for simulation.

  10. Why are social network transactions important? Evidence based on the concentration of key suppliers and customers in China

    Directory of Open Access Journals (Sweden)

    Xiang Kong

    2011-09-01

    Full Text Available Based on a new institutional economy framework, this study examines the formation and economic consequences of social networks (guanxi from the perspective of key suppliers and customers in China. Results show that commercial activities which depend on networks are determined by the institutional environment. For example, companies that have lower accumulated social capital (less trust among people and are subject to more government invention depend more on social network transactions than on the market. In addition, this study shows that network transactions can provide benefits to firms, especially in weak institutional environments. Networks can reduce transaction costs by reducing information asymmetry, i.e., increased network dependence is associated with lower credit costs and lower advertising and sales costs. Networks can also reduce the effect of industry shocks, especially negative shocks, by creating a bonding mechanism. This study contributes to our understanding of social networks in emerging markets by providing evidence on network transactions with key suppliers and customers and their influence on firms’ accounting behavior.

  11. A Self-Adaptive Energy-Efficient Framework for Large Unattended Wireless Sensor Networks

    Science.gov (United States)

    2014-11-06

    Transactions on Vehicular Technology, (10 2011): 3919. doi: 10.1109/ TVT .2011.2166093 Miao Zhao, Yuanyuan Yang. Optimization-Based DistributedAlgorithms for...Networks, IEEE Transactions on Vehicular Technology, (05 2013): 0. doi: 10.1109/ TVT .2012.2229309 Miao Zhao, Ming Ma, Yuanyuan Yang. Applying

  12. Performance IEEE 802.14.5 and zigbee protocol on realtime monitoring augmented reality based wireless sensor network system

    Directory of Open Access Journals (Sweden)

    Arda Surya Editya

    2017-07-01

    Full Text Available The internet of Thing (IoTtechnology has much development in this era. It has various wireless media transmission systems such as ESP and XBEE. Some IoT device can monitor website or application. On the other hand, Augmented Reality (AR is a technology that used more on the entertainment sector. Here, we try to use AR to monitor the xbee based IoT device. As a result, there is the different result between Zigbee Protocol and IEEE 802.14.5 real time monitoring system. The optimum estimation of realtime time tolerance of those monitoring systems is >1500 ms (IEEE 804.14.5 and > 50 ms (Zigbee protocol.

  13. Optimal Throughput and Self-adaptability of Robust Real-Time IEEE 802.15.4 MAC for AMI Mesh Network

    Science.gov (United States)

    Shabani, Hikma; Mohamud Ahmed, Musse; Khan, Sheroz; Hameed, Shahab Ahmed; Hadi Habaebi, Mohamed

    2013-12-01

    A smart grid refers to a modernization of the electricity system that brings intelligence, reliability, efficiency and optimality to the power grid. To provide an automated and widely distributed energy delivery, the smart grid will be branded by a two-way flow of electricity and information system between energy suppliers and their customers. Thus, the smart grid is a power grid that integrates data communication networks which provide the collected and analysed data at all levels in real time. Therefore, the performance of communication systems is so vital for the success of smart grid. Merit to the ZigBee/IEEE802.15.4std low cost, low power, low data rate, short range, simplicity and free licensed spectrum that makes wireless sensor networks (WSNs) the most suitable wireless technology for smart grid applications. Unfortunately, almost all ZigBee channels overlap with wireless local area network (WLAN) channels, resulting in severe performance degradation due to interference. In order to improve the performance of communication systems, this paper proposes an optimal throughput and self-adaptability of ZigBee/IEEE802.15.4std for smart grid.

  14. An Improved Approach for RSSI-Based only Calibration-Free Real-Time Indoor Localization on IEEE 802.11 and 802.15.4 Wireless Networks

    Directory of Open Access Journals (Sweden)

    Marco Passafiume

    2017-03-01

    Full Text Available Assuming a reliable and responsive spatial contextualization service is a must-have in IEEE 802.11 and 802.15.4 wireless networks, a suitable approach consists of the implementation of localization capabilities, as an additional application layer to the communication protocol stack. Considering the applicative scenario where satellite-based positioning applications are denied, such as indoor environments, and excluding data packet arrivals time measurements due to lack of time resolution, received signal strength indicator (RSSI measurements, obtained according to IEEE 802.11 and 802.15.4 data access technologies, are the unique data sources suitable for indoor geo-referencing using COTS devices. In the existing literature, many RSSI based localization systems are introduced and experimentally validated, nevertheless they require periodic calibrations and significant information fusion from different sensors that dramatically decrease overall systems reliability and their effective availability. This motivates the work presented in this paper, which introduces an approach for an RSSI-based calibration-free and real-time indoor localization. While switched-beam array-based hardware (compliant with IEEE 802.15.4 router functionality has already been presented by the author, the focus of this paper is the creation of an algorithmic layer for use with the pre-existing hardware capable to enable full localization and data contextualization over a standard 802.15.4 wireless sensor network using only RSSI information without the need of lengthy offline calibration phase. System validation reports the localization results in a typical indoor site, where the system has shown high accuracy, leading to a sub-metrical overall mean error and an almost 100% site coverage within 1 m localization error.

  15. An Improved Approach for RSSI-Based only Calibration-Free Real-Time Indoor Localization on IEEE 802.11 and 802.15.4 Wireless Networks.

    Science.gov (United States)

    Passafiume, Marco; Maddio, Stefano; Cidronali, Alessandro

    2017-03-29

    Assuming a reliable and responsive spatial contextualization service is a must-have in IEEE 802.11 and 802.15.4 wireless networks, a suitable approach consists of the implementation of localization capabilities, as an additional application layer to the communication protocol stack. Considering the applicative scenario where satellite-based positioning applications are denied, such as indoor environments, and excluding data packet arrivals time measurements due to lack of time resolution, received signal strength indicator (RSSI) measurements, obtained according to IEEE 802.11 and 802.15.4 data access technologies, are the unique data sources suitable for indoor geo-referencing using COTS devices. In the existing literature, many RSSI based localization systems are introduced and experimentally validated, nevertheless they require periodic calibrations and significant information fusion from different sensors that dramatically decrease overall systems reliability and their effective availability. This motivates the work presented in this paper, which introduces an approach for an RSSI-based calibration-free and real-time indoor localization. While switched-beam array-based hardware (compliant with IEEE 802.15.4 router functionality) has already been presented by the author, the focus of this paper is the creation of an algorithmic layer for use with the pre-existing hardware capable to enable full localization and data contextualization over a standard 802.15.4 wireless sensor network using only RSSI information without the need of lengthy offline calibration phase. System validation reports the localization results in a typical indoor site, where the system has shown high accuracy, leading to a sub-metrical overall mean error and an almost 100% site coverage within 1 m localization error.

  16. The Drayang Girls of Thimphu: sexual network formation, transactional sex and emerging modernities in Bhutan.

    Science.gov (United States)

    Lorway, Robert; Dorji, Gampo; Bradley, Janet; Ramesh, B M; Isaac, Shajy; Blanchard, James

    2011-12-01

    Bhutan's sustained low HIV prevalence can be attributed to its political commitment to maintain isolation from foreign cultural influence. Recently, rising HIV prevalence has coincided with the increase in human traffic along Bhutan's borders. The majority of infections, occurring primarily through sexual contact, have appeared in the urban environments that are situated along the main transport routes. This qualitative study explored the sexual networks that form at entertainment venues in the capital city of Thimphu. To more fully understand sexual network formation at theses venues, one must take into account an emerging modernity that reflects a convergence of cultural, economic and political influences emanating from Bhutan's unique 'middle-path' modernisation scheme. The growing appearance of transactional sex in Thimphu not only points to an emergent form of exploitation wrought by larger economic transformations and widening social inequalities; the power inequalities that surround its practice are also significantly exacerbated by the local cultural politics and moral ideologies that arise as Bhutan proceeds along the path towards global capitalism. Discourses of Bhutanese sexual morality articulate with broader political economic transformations to forcefully position village women engaging in transactional sex within a field of power relations that leaves them open to various forms of subjugation.

  17. Robust Network Design - Connectivity and Beyond

    Science.gov (United States)

    2015-01-15

    data integrity part in subsections IIC, IID, IIE and IIF. II.A. RESOURCE EFFICIENT BACKBONE NETWORK DESIGN IN FAULT-FREE SCENARIO Prior to our...Optical Networks”, IEEE Transactions on Networking 25. S. Shirazipourazad, P. Ghosh and A. Sen, “On Connectivity of Airborne Networks” AIAA Journal of

  18. Fundamentals of computational intelligence neural networks, fuzzy systems, and evolutionary computation

    CERN Document Server

    Keller, James M; Fogel, David B

    2016-01-01

    This book covers the three fundamental topics that form the basis of computational intelligence: neural networks, fuzzy systems, and evolutionary computation. The text focuses on inspiration, design, theory, and practical aspects of implementing procedures to solve real-world problems. While other books in the three fields that comprise computational intelligence are written by specialists in one discipline, this book is co-written by current former Editor-in-Chief of IEEE Transactions on Neural Networks and Learning Systems, a former Editor-in-Chief of IEEE Transactions on Fuzzy Systems, and the founding Editor-in-Chief of IEEE Transactions on Evolutionary Computation. The coverage across the three topics is both uniform and consistent in style and notation. Discusses single-layer and multilayer neural networks, radial-basi function networks, and recurrent neural networks Covers fuzzy set theory, fuzzy relations, fuzzy logic interference, fuzzy clustering and classification, fuzzy measures and fuzz...

  19. A Methodology For Measuring Resilience in a Satellite-Based Communication Network

    Science.gov (United States)

    2014-03-27

    continuous multicommodity flow network interdiction problems.” IIE Transactions , 39:1, 15-26. April 2007. http://dx.doi.org/10.1080/07408170600729192... Transactions on Power Systems: Volume 20, Number 2. May 2005 Bard, Jonathan. “Practical Bilevel Optimization: Algorithms and Applications...Salmeron, Javier & Kevin Wood, Ross Baldick. “Analysis of Electric Grid Security Under Terrorist Threat”. IEEE Transactions on Power Systems, Vol. 19

  20. An integrated PHY-MAC analytical model for IEEE 802.15.7 VLC network with MPR capability

    Science.gov (United States)

    Yu, Hai-feng; Chi, Xue-fen; Liu, Jian

    2014-09-01

    Considering that the collision caused by hidden terminal is particularly serious due to the narrow beams of optical devices, the multi-packet reception (MPR) is introduced to mitigate the collisions for IEEE 802.15.7 visible light communication (VLC) system. To explore the impact of MPR on system performance and investigate the interaction between physical (PHY) layer and media access control (MAC) layer, a three dimensional (3D) integrated PHY-MAC analytical model of carrier sense multiple access/collision avoidance (CSMA/CA) is established based on Markov chain theory for VLC system, in which MPR is implemented through the use of orthogonal code sequence. Throughput is derived to evaluate the performance of VLC system with MPR capability under imperfect optical channel. The results can be used for the performance optimization of a VLC system with MPR capability.

  1. Network strength, transaction-specific investments, inter-personal trust, and relationship satisfaction in Chinese agrifood SMEs

    NARCIS (Netherlands)

    Lu Hualiang,; Feng, S.; Trienekens, J.H.; Omta, S.W.F.

    2012-01-01

    Purpose - The purpose of this paper is to investigate the effects of network strength, transaction-specific investments and inter-personal trust on business relationship satisfaction for small-and-medium-sized enterprises (SMEs) involved in agri-food processing and exporting in China.

  2. Economic Assessment of Network-Constrained Transactive Energy for Managing Flexible Demand in Distribution Systems

    Directory of Open Access Journals (Sweden)

    Junjie Hu

    2017-05-01

    Full Text Available The increasing number of distributed energy resources such as electric vehicles and heat pumps connected to power systems raises operational challenges to the network operator, for example, introducing grid congestion and voltage deviations in the distribution network level if their operations are not properly coordinated. Coordination and control of a large number of distributed energy resources requires innovative approaches. In this paper, we follow up on a recently proposed network-constrained transactive energy (NCTE method for scheduling of electric vehicles and heat pumps within a retailer’s aggregation at distribution system level. We extend this method with: (1 a new modeling technique that allows the resulting congestion price to be directly interpreted as a locational marginal pricing in the system; (2 an explicit analysis of the benefits and costs of different actors when using the NCTE method in the system, given the high penetration of distributed energy resources. This paper firstly describes the NCTE-based distribution system that introduces a new interacting scheme for actors at the distribution system level. Then, technical modeling and economic interpretation of the NCTE-based distribution system are described. Finally, we show the benefits and costs of different actors within the NCTE-based distribution system.

  3. 1991 IEEE International Joint Conference on Neural Networks, Singapore, Nov. 18-21, 1991, Proceedings. Vols. 1-3

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The present conference the application of neural networks to associative memories, neurorecognition, hybrid systems, supervised and unsupervised learning, image processing, neurophysiology, sensation and perception, electrical neurocomputers, optimization, robotics, machine vision, sensorimotor control systems, and neurodynamics. Attention is given to such topics as optimal associative mappings in recurrent networks, self-improving associative neural network models, fuzzy activation functions, adaptive pattern recognition with sparse associative networks, efficient question-answering in a hybrid system, the use of abstractions by neural networks, remote-sensing pattern classification, speech recognition with guided propagation, inverse-step competitive learning, and rotational quadratic function neural networks. Also discussed are electrical load forecasting, evolutionarily stable and unstable strategies, the capacity of recurrent networks, neural net vs control theory, perceptrons for image recognition, storage capacity of bidirectional associative memories, associative random optimization for control, automatic synthesis of digital neural architectures, self-learning robot vision, and the associative dynamics of chaotic neural networks.

  4. Wireless Sensor Network Metrics for Real-Time Systems

    Science.gov (United States)

    2009-05-20

    layer standard [119]. Zigbee is initially targeted at energy management and efficiency, home automation , building automation, and industrial automation...Hong-Hee Lee, “Network-based fire-detection system via con- troller area network for smart home automation ,” IEEE Transactions on Consumer Electronics

  5. A Study of the Merits of Precision Time Protocol (IEEE-1588) Across High-Speed Data Networks

    CERN Document Server

    Oliver, David; Neufeld, Niko

    2015-01-01

    By using Precision Time Protocol across high-speed data networks, it is possible to achieve good time synchronisation without requiring the use of custom switches. Even under heavy network loads, the attainable precision far exceeds that which is possible with Network Time Protocol, and is sufficient for many applications. This note explores the attainable precision possible with PTP under various conditions and attempts to provide a measurement of its performance.

  6. A Study of the Merits of Precision Time Protocol (IEEE-1588) Across High-Speed Data Networks

    CERN Document Server

    Oliver, David; Otto, Adam Jedrzej; CERN. Geneva. PH Department

    2015-01-01

    By using Precision Time Protocol across high-speed data networks, it is possible to achieve good time synchronisation using only commercial, off-the-shelve equipment. Even under heavy network loads, the attainable precision far exceeds that which is possible with Network Time Protocol, and is sufficient for many applications. This note explores the time precision possible with PTP under various conditions and attempts to provide a measurement of its performance.

  7. Transactional Distributed Shared Memory

    Science.gov (United States)

    1992-07-01

    consisted of Joshua Bloch, Dean Daniels, Richard Draves, Dan Duchamp , Jeffrey Eppinger, Elliot Jaffe, Toshihiko Kato, George Michaels, Lily Mummert, Randy...34 Non-blocking commit. The non-blocking commit protocol [LeLann 81, Duchamp 89] is a modification of two-phase commit to guarantee that at least one...Architecture, pages "*-442. IEEE, 1986. Computer Architecture News Volume 14 Number 2. [ Duchamp 89] Dan Duchamp . Transaction Management. PhD thesis, Carnegie

  8. Managerial responses to transaction cost disequilibrium in food supply chains and networks

    NARCIS (Netherlands)

    Bremmers, H.J.; Meulen, van der B.M.J.; Poppe, K.J.; Wijnands, J.H.M.

    2010-01-01

    Differences in transaction costs (i.e. costs of information processing, monitoring and control) between firms in local supply chains as well as in an international setting may have a negative impact on competitiveness and on creation of value added. Transaction cost disequilibrium is defined as a

  9. Governance structure, perception and innovation in credence food transactions: the role of community networks

    NARCIS (Netherlands)

    Pascucci, S.

    2010-01-01

    Promoting transactions of more sustainable-oriented foods can be (socially and privately) complex and costly. New institutional economics (NIE) explains these dynamics by analyzing the choice of the "most cost-economizing" governance structure to carry out a transaction where credence attributes are

  10. Fluid-Flow Modeling of a Relay Node in an IEEE 802.11 Wireless Ad-Hoc Network

    NARCIS (Netherlands)

    Roijers, F.; van den Berg, H; Mandjes, M.R.H.

    2007-01-01

    Abstract Wireless ad-hoc networks are based on shared medium technology where the nodes arrange access to the medium in a distributed way independent of their current traffic demand. This has the inherent drawback that a node that serves as a relay node for transmissions of multiple neighboring

  11. Fluid-flow modeling of a relay node in an IEEE 802.11 wireless ad-hoc network

    NARCIS (Netherlands)

    F. Roijers (Frank); J.L. van den Berg (Hans); M.R.H. Mandjes (Michel)

    2007-01-01

    textabstractWireless ad-hoc networks are based on shared medium technology where the nodes arrange access to the medium in a distributed way independent of their current traffic demand. This has the inherent drawback that a node that serves as a relay node for transmissions of multiple neighboring

  12. Fluid-flow modeling of a relay node in an IEEE 802.11 wireless ad-hoc network

    NARCIS (Netherlands)

    Roijers, F.; Berg, J.L. van den; Mandjes, M.

    2007-01-01

    Wireless ad-hoc networks are based on shared medium technology where the nodes arrange access to the medium in a distributed way independent of their current traffic demand. This has the inherent drawback that a node that serves as a relay node for transmissions of multiple neighboring nodes is

  13. The promise of downlink MU-MIMO for high-capacity next generation mobile broadband networks based on IEEE 802.16 m

    Directory of Open Access Journals (Sweden)

    Papathanassiou Apostolos

    2011-01-01

    Full Text Available Abstract The dramatic increase of the demand for mobile broadband services poses stringent requirements on the performance evolution of currently deployed mobile broadband networks, such as Mobile WiMAX Release 1 and 3GPP LTE Release 8. Although the combination of single-user multiple-input multiple-output (SU-MIMO and orthogonal frequency division multiple access (OFDMA provide the appropriate technologies for improving the downlink performance of third generation (3G code division multiple access (CDMA-based mobile radio systems and, thus, address the current mobile internet requirements, a fundamental paradigm shift is required to cope with the constantly increasing mobile broadband data rate and spectral efficiency requirements. Among the different technologies available for making the paradigm shift from current to next-generation mobile broadband networks, multiuser MIMO (MU-MIMO constitutes the most promising technology because of its significant performance improvement advantages. In this article, we analyze the performance of MU-MIMO under a multitude of deployment scenarios and system parameters through extensive system-level simulations which are based on widely used system-level evaluation methodologies. The target mobile broadband system used in the simulations is IEEE 802.16 m which was recently adopted by ITU-R as an IMT-Advanced technology along with 3GPP LTE-Advanced. The results provide insights into different aspects of MU-MIMO with respect to system-level performance, parameter sensitivity, and deployment scenarios, and they can be used by the mobile broadband network designer for maximizing the benefits of MU-MIMO in a scenario with specific deployment requirements and goals.

  14. Do the rich get richer? An empirical analysis of the Bitcoin transaction network

    National Research Council Canada - National Science Library

    Kondor, Dániel; Pósfai, Márton; Csabai, István; Vattay, Gábor

    2014-01-01

    .... the resulting wealth distribution) are compared to real-world data. In this paper, we analyze Bitcoin, which is a novel digital currency system, where the complete list of transactions is publicly available...

  15. Deficit Round Robin with Fragmentation Scheduling to Achieve Generalized Weighted Fairness for Resource Allocation in IEEE 802.16e Mobile WiMAX Networks

    Directory of Open Access Journals (Sweden)

    Chakchai So-In

    2010-10-01

    Full Text Available Deficit Round Robin (DRR is a fair packet-based scheduling discipline commonly used in wired networks where link capacities do not change with time. However, in wireless networks, especially wireless broadband networks, i.e., IEEE 802.16e Mobile WiMAX, there are two main considerations violate the packet-based service concept for DRR. First, the resources are allocated per Mobile WiMAX frame. To achieve full frame utilization, Mobile WiMAX allows packets to be fragmented. Second, due to a high variation in wireless channel conditions, the link/channel capacity can change over time and location. Therefore, we introduce a Deficit Round Robin with Fragmentation (DRRF to allocate resources per Mobile WiMAX frame in a fair manner by allowing for varying link capacity and for transmitting fragmented packets. Similar to DRR and Generalized Processor Sharing (GPS, DRRF achieves perfect fairness. DRRF results in a higher throughput than DRR (80% improvement while causing less overhead than GPS (8 times less than GPS. In addition, in Mobile WiMAX, the quality of service (QoS offered by service providers is associated with the price paid. This is similar to a cellular phone system; the users may be required to pay air-time charges. Hence, we have also formalized a Generalized Weighted Fairness (GWF criterion which equalizes a weighted sum of service time units or slots, called temporal fairness, and transmitted bytes, called throughput fairness, for customers who are located in a poor channel condition or at a further distance versus for those who are near the base stations, or have a good channel condition. We use DRRF to demonstrate the application of GWF. These fairness criteria are used to satisfy basic requirements for resource allocation, especially for non real-time traffic. Therefore, we also extend DRRF to support other QoS requirements, such as minimum reserved traffic rate, maximum sustained traffic rate, and traffic priority. For real

  16. INCLUSIÓN DE CORRELACIONES TEMPORALES CON DEPENDENCIA A LARGO PLAZO Y PATRONES AUTOSIMILARES EN MODELOS DE REDES IEEE 802.3 INCLUSION OF LONG-RANGE-DEPENDENT TEMPORARY CORRELATIONS AND SELF-SIMILAR PATTERNS IN IEEE 802.3 NETWORKS MODELS

    Directory of Open Access Journals (Sweden)

    Ginno Millán Naveas

    2010-04-01

    Full Text Available En este trabajo se presentan los fundamentos de un proyecto de investigación sobre el modelado de redes de computadoras con mecanismo de control de acceso al medio, según el estándar IEEE 802.3-2005, empleando los postulados de la teoría de conjuntos autosimilares para establecer el nivel de impacto que poseen las correlaciones temporales con dependencia de largo alcance sobre el rendimiento de tales redes. Se postula una nueva forma de estimar grados de autosimilaridad basada en una variación del estimador de Whittle.The foundation of a research project about a model of computer networks with media access control mechanism based on the IEEE standard 802.3-2005 is presented. The model draws from the theory of self-similar sets for establishing the impact level that the long-range-dependent temporary correlations have on the performance of such networks. A new method for the estimation of self-similar levels based on a variation of the Whittle estimator is postulated.

  17. Fiber Segment-Based Degradation Methods for a Finite Element-Informed Structural Brain Network

    Science.gov (United States)

    2013-11-01

    structural injury translates to functional network changes. 20 5. References 1. Pascrell House Home Page. Congressional Brain Injury Task Force... Audiovisual Stimulation by Partial Directed Coherence Analysis. IEEE Transactions on Biomedical Engineering 2009, 56 (11), 2721–2724. 21. Horgan, T. J

  18. Proceedings of IEEE Machine Learning for Signal Processing Workshop XV

    DEFF Research Database (Denmark)

    Larsen, Jan

    These proceedings contains refereed papers presented at the Fifteenth IEEE Workshop on Machine Learning for Signal Processing (MLSP’2005), held in Mystic, Connecticut, USA, September 28-30, 2005. This is a continuation of the IEEE Workshops on Neural Networks for Signal Processing (NNSP) organized...... by the NNSP Technical Committee of the IEEE Signal Processing Society. The name of the Technical Committee, hence of the Workshop, was changed to Machine Learning for Signal Processing in September 2003 to better reflect the areas represented by the Technical Committee. The conference is organized...... by the Machine Learning for Signal Processing Technical Committee with sponsorship of the IEEE Signal Processing Society. Following the practice started two years ago, the bound volume of the proceedings is going to be published by IEEE following the Workshop, and we are pleased to offer to conference attendees...

  19. Simulasi Kinerja Jaringan Nirkabel IEEE-802.11a dan IEEE-802.11g Menggunakan NS-2

    Directory of Open Access Journals (Sweden)

    Helm Fitriawan

    2014-03-01

    Full Text Available Wireless network uses transmission media based on radio waves. This type of networks is mainly useddue to its efficiency and mobility in data exchanging. This paper reports the modeling and simulation of wirelessnetworks based on Cisco Aironet 1130ag access point devices with IEEE 802.11a and IEEE 802.11g standards. Themodeling and simulation are performed using network simulator version 2 (NS-2 that is installed on operationsystem Linux Ubuntu v.10.10. The NS-2 is commonly used and works well in numerous types of network simulation. From simulation, we obtain quality of service parameters by employing several simulation scenarios in terms ofnumber of nodes, distances, and packet data sizes. It can be concluded from simulation results that the IEEE 802.11gnetworks transfer data with better quality than those of IEEE 802.11a networks.  Furthermore, the IEEE 802.11gnetworks provide a higher throughput, with smaller amount of delay and packet loss percentage compared to thoseof IEEE 802.11a networks.

  20. IEEE Prize for Lucio Rossi

    CERN Multimedia

    IEEE Council on Superconductivity

    2007-01-01

    Lucio Rossi receives his prize from John Spargo, Chairman of the IEEE Council on Superconductivity (left), and Martin Nisenoff, Chairman of the Council on Superconductivity's Awards Committee (right).

  1. Measuring the influence of networks on transaction costs using a non-parametric regression technique

    DEFF Research Database (Denmark)

    Henningsen, Géraldine; Henningsen, Arne; Henning, Christian H.C.A.

    . We empirically analyse the effect of networks on productivity using a cross-validated local linear non-parametric regression technique and a data set of 384 farms in Poland. Our empirical study generally supports our hypothesis that networks affect productivity. Large and dense trading networks...

  2. Analysis of the transmission characteristics of China's carbon market transaction price volatility from the perspective of a complex network.

    Science.gov (United States)

    Jia, Jingjing; Li, Huajiao; Zhou, Jinsheng; Jiang, Meihui; Dong, Di

    2017-12-23

    Research on the price fluctuation transmission of the carbon trading pilot market is of great significance for the establishment of China's unified carbon market and its development in the future. In this paper, the carbon market transaction prices of Beijing, Shanghai, Tianjin, Shenzhen, and Guangdong were selected from December 29, 2013 to March 26, 2016, as sample data. Based on the view of the complex network theory, we construct a price fluctuation transmission network model of five pilot carbon markets in China, with the purposes of analyzing the topological features of this network, including point intensity, weighted clustering coefficient, betweenness centrality, and community structure, and elucidating the characteristics and transmission mechanism of price fluctuation in China's five pilot cities. The results of point intensity and weighted clustering coefficient show that the carbon prices in the five markets remained unchanged and transmitted smoothly in general, and price fragmentation is serious; however, at some point, the price fluctuates with mass phenomena. The result of betweenness centrality reflects that a small number of price fluctuations can control the whole market carbon price transmission and price fluctuation evolves in an alternate manner. The study provides direction for the scientific management of the carbon price. Policy makers should take a positive role in promoting market activity, preventing the risks that may arise from mass trade and scientifically forecasting the volatility of trading prices, which will provide experience for the establishment of a unified carbon market in China.

  3. IEEE 802.11s Analysis And Simulation

    OpenAIRE

    Alfonso Delgado, Diego

    2015-01-01

    [ANGLÈS] Simulation of wifi networks using ieee802.11s to collect data and help to develop this new standard. [CASTELLÀ] Simulacion de redes wifi usando el protocolo ieee802.11s para recopilar datos y estadisticas que ayuden en el desarrollo de este nuevo estandar. [CATALÀ] Simulació de xarxes wifi usant el protocol ieee802.11s per recopilar dades i estadístiques que ajudin en el desenvolupament d'aquest nou estàndard.

  4. Transactional Memory

    CERN Document Server

    Harris, Tim; Rajwar, Ravi

    2010-01-01

    The advent of multicore processors has renewed interest in the idea of incorporating transactions into the programming model used to write parallel programs.This approach, known as transactional memory, offers an alternative, and hopefully better, way to coordinate concurrent threads. The ACI(atomicity, consistency, isolation) properties of transactions provide a foundation to ensure that concurrent reads and writes of shared data do not produce inconsistent or incorrect results. At a higher level, a computation wrapped in a transaction executes atomically - either it completes successfullyand

  5. Access to IEEE Electronic Library

    CERN Multimedia

    2007-01-01

    From 2007, the CERN Library now offers readers online access to the complete IEEE Electronic Library (Institute of Electrical and Electronics Engineers). This new licence gives unlimited online access to all IEEE and IET (previously IEE) journals and proceedings as well as all current IEEE standards and selected archived ones. Some of the titles offer volumes back to 1913. This service currently represents more than 1,400,000 full-text articles! This leading engineering information resource replaces the previous service, a sub-product of the IEEE database called 'IEEE Enterprise', which offered online access to the complete collection of IEEE journals and proceedings, but with limited features. The service had become so popular that the CERN Working Group for Acquisitions recommended that the Library subscribe to the complete IEEE Electronic Library for 2007. Usage statistics for recent months showed there was a demand for the service from a large community of CERN users and we were aware that many users h...

  6. Vehicular Networking Conference (VNC)

    NARCIS (Netherlands)

    Altintas, O.; Chen, W.; Heijenk, Geert; Dressler, F.; Ekici, E.; Kargl, Frank; Shigeno, H.; Dietzel, Stefan

    2011-01-01

    On behalf of the Organizing Committee, we would like to welcome you to the third edition of the IEEE Vehicular Networking Conference (IEEE VNC 2011) in Amsterdam, the Netherlands. IEEE VNC is a unique conference sponsored by both the IEEE Communications Society and the IEEE Intelligent

  7. IEEE transactions on vehicular technology, Vol. Vt-19, No. 1

    Science.gov (United States)

    1970-02-01

    This special issue deals not only with integrated electronic systems but with the technology that is required to achieve successful operation. To place some of the 1969 dimensions of the highway system in the United States in proper focus, we note th...

  8. Application of Network-Constrained Transactive Control to Electric Vehicle Charging for Secure Grid Operation

    DEFF Research Database (Denmark)

    Hu, Junjie; Yang, Guangya; Bindner, Henrik W.

    2016-01-01

    including power transformer congestion and voltage violations. In this method, a price coordinator is introduced to facilitate the interaction between the distribution system operator (DSO) and aggregators in the smart grid. Electric vehicles are used to illustrate the proposed network...

  9. A Reliable Data Transmission Model for IEEE 802.15.4e Enabled Wireless Sensor Network under WiFi Interference.

    Science.gov (United States)

    Sahoo, Prasan Kumar; Pattanaik, Sudhir Ranjan; Wu, Shih-Lin

    2017-06-07

    The IEEE 802.15.4e standard proposes Medium Access Control (MAC) to support collision-free wireless channel access mechanisms for industrial, commercial and healthcare applications. However, unnecessary wastage of energy and bandwidth consumption occur due to inefficient backoff management and collisions. In this paper, a new channel access mechanism is designed for the buffer constraint sensor devices to reduce the packet drop rate, energy consumption and collisions. In order to avoid collision due to the hidden terminal problem, a new frame structure is designed for the data transmission. A new superframe structure is proposed to mitigate the problems due to WiFi and ZigBee interference. A modified superframe structure with a new retransmission opportunity for failure devices is proposed to reduce the collisions and retransmission delay with high reliability. Performance evaluation and validation of our scheme indicate that the packet drop rate, throughput, reliability, energy consumption and average delay of the nodes can be improved significantly.

  10. Social networks, market transactions, and reputation as a central resource. The Mercado del Mar, a fish market in central Mexico.

    Science.gov (United States)

    Pedroza-Gutiérrez, Carmen; Hernández, Juan M

    2017-01-01

    Fish consumption in Mexico is considered low (around 12 kg per person per year) and non-homogeneously distributed across the country. One of the reasons for this situation is the scarcity of wholesale selling sites. In this context, the Mercado del Mar (MM), located in Guadalajara city, Jalisco, is the second biggest wholesale fish market in Mexico, with a distribution of about 500 tons per day and a variety of about 350 different species of fish. In this paper, we argue that MM has accumulated social capital, which is formed from two main resources: buyer and seller relationships, and reputation. Specifically, the MM manages a broad and intensive interaction among business actors and the already achieved reputation allows the MM to adapt to market changes. To validate our hypotheses, an empirical study was conducted in 2015 by means of interviews to fish wholesalers in the MM and a sample of their suppliers and buyers. For simplicity we have only considered fresh water fish. We have followed snow-ball sampling as the survey strategy. Results show that the MM has responded to fish market dynamics organizing a complex network of buyers and suppliers whose relationships can be explained in the form of strong and weak ties. At the same time, reputation has been the central resource to build this social capital and also gives place to market transactions. Additionally, the strategic position of Guadalajara city and the well-connected routes have facilitated fish bulking and distribution in the region.

  11. Social networks, market transactions, and reputation as a central resource. The Mercado del Mar, a fish market in central Mexico.

    Directory of Open Access Journals (Sweden)

    Carmen Pedroza-Gutiérrez

    Full Text Available Fish consumption in Mexico is considered low (around 12 kg per person per year and non-homogeneously distributed across the country. One of the reasons for this situation is the scarcity of wholesale selling sites. In this context, the Mercado del Mar (MM, located in Guadalajara city, Jalisco, is the second biggest wholesale fish market in Mexico, with a distribution of about 500 tons per day and a variety of about 350 different species of fish. In this paper, we argue that MM has accumulated social capital, which is formed from two main resources: buyer and seller relationships, and reputation. Specifically, the MM manages a broad and intensive interaction among business actors and the already achieved reputation allows the MM to adapt to market changes. To validate our hypotheses, an empirical study was conducted in 2015 by means of interviews to fish wholesalers in the MM and a sample of their suppliers and buyers. For simplicity we have only considered fresh water fish. We have followed snow-ball sampling as the survey strategy. Results show that the MM has responded to fish market dynamics organizing a complex network of buyers and suppliers whose relationships can be explained in the form of strong and weak ties. At the same time, reputation has been the central resource to build this social capital and also gives place to market transactions. Additionally, the strategic position of Guadalajara city and the well-connected routes have facilitated fish bulking and distribution in the region.

  12. Communicating Transactions

    Science.gov (United States)

    de Vries, Edsko; Koutavas, Vasileios; Hennessy, Matthew

    We propose a novel language construct called communicating transactions, obtained by dropping the isolation requirement from classical transactions, which can be used to model automatic error recovery in distributed systems. We extend CCS with this construct and give a simple semantics for the extended calculus, called TransCCS. We develop a behavioural theory which is sound and complete with respect to the may-testing preorder, and use it to prove interesting laws and reason compositionally about example systems. Finally, we prove that communicating transactions do not increase the observational power of processes; thus CCS equivalences are preserved in the extended language.

  13. Coexistence of IEEE 802.11b/g WLANs and IEEE 802.15.4 WSNs : Modeling and Protocol Enhancements

    NARCIS (Netherlands)

    Yuan, W.

    2011-01-01

    As an emerging short-range wireless technology, IEEE 802.15.4/ZigBee Wireless Sensor Networks (WSNs) are increasingly used in the fields of home control, industrial control, consumer electronics, energy management, building automation, telecom services, personal healthcare, etc. IEEE

  14. An Adaptive Recurrent Neural Network for Remaining Useful Life Prediction of Lithium-ion Batteries

    Science.gov (United States)

    2010-10-01

    application for RUL prediction. We compare its performance with the classical recurrent neural network (RNN) and the recurrent neural fuzzy system ...Jang (1993). ANFIS: adaptive-network-based fuzzy inference system , IEEE Transactions on Systems , Man, and Cybernetics-Part B: Cybernetics, vol. 23...pp. 665-685, 1993. J. Jang, C. T. Sun, and E. Mizutani (1997). Neuro - Fuzzy and Soft Computing: A computational approach to learning and machine

  15. Introduction to IEEE P1900.4 Activities

    Science.gov (United States)

    Buljore, Soodesh; Muck, Markus; Martigne, Patricia; Houzé, Paul; Harada, Hiroshi; Ishizu, Kentaro; Holland, Oliver; Mihailovic, Andrej; Tsagkaris, Kostas A.; Sallent, Oriol; Clemo, Gary; Sooriyabandara, Mahesh; Ivanov, Vladimir; Nolte, Klaus; Stametalos, Makis

    The Project Authorization Request (PAR) for the IEEE P1900.4 Working Group (WG), under the IEEE Standards Coordinating Committee 41 (SCC41) was approved in December 2006, leading to this WG being officially launched in February 2007 [1]. The scope of this standard is to devise a functional architecture comprising building blocks to enable coordinated network-device distributed decision making, with the goal of aiding the optimization of radio resource usage, including spectrum access control, in heterogeneous wireless access networks. This paper introduces the activities and work under progress in IEEE P1900.4, including its scope and purpose in Sects. 1 and 2, the reference usage scenarios where the standard would be applicable in Sect. 4, and its current system architecture in Sect. 5.

  16. Enhanced Precision Geolocation in 4G Wireless Networks

    Science.gov (United States)

    2013-03-01

    mobile user location for wideband CDMA cellular systems,” IEEE Transactions on Wireless Communications, vol. 1, no. 3, pp. 439–447, Jul. 2002. [12...errors. 14. SUBJECT TERMS geolocation, algorithms, 4G mobile communication, optimization, WiMAX, Wireless networks 15. NUMBER OF PAGES 251 16. PRICE... mobile subscriber position as the intersection of three range circles. . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Figure 3. The case of

  17. Toward a Mobility-Driven Architecture for Multimodal Underwater Networking

    Science.gov (United States)

    2017-02-01

    interest in the undersea domain, sparked by applications including environmental monitoring, deep-sea exploration and exploitation, and undersea...allow them to gather large volumes of data, ranging from acoustic and environmental measurements to high-resolution imagery and video. Although they...of Partially Observed Dynamical Processes over Networks via Dictionary Learning,” IEEE Transactions on Signal Processing. vol. 62, no. 13 (July), pp

  18. IEEE Conference Publications in Libraries.

    Science.gov (United States)

    Johnson, Karl E.

    1984-01-01

    Conclusions of surveys (63 libraries, OCLC database, University of Rhode Island users) assessing handling of Institute of Electrical and Electronics Engineers (IEEE) conference publications indicate that most libraries fully catalog these publications using LC cataloging, and library patrons frequently require series access to publications. Eight…

  19. Identifying Bitcoin users by transaction behavior

    Science.gov (United States)

    Monaco, John V.

    2015-05-01

    Digital currencies, such as Bitcoin, offer convenience and security to criminals operating in the black marketplace. Some Bitcoin marketplaces, such as Silk Road, even claim anonymity. This claim contradicts the findings in this work, where long term transactional behavior is used to identify and verify account holders. Transaction timestamps and network properties observed over time contribute to this finding. The timestamp of each transaction is the result of many factors: the desire purchase an item, daily schedule and activities, as well as hardware and network latency. Dynamic network properties of the transaction, such as coin flow and the number of edge outputs and inputs, contribute further to reveal account identity. In this paper, we propose a novel methodology for identifying and verifying Bitcoin users based on the observation of Bitcoin transactions over time. The behavior we attempt to quantify roughly occurs in the social band of Newell's time scale. A subset of the Blockchain 230686 is taken, selecting users that initiated between 100 and 1000 unique transactions per month for at least 6 different months. This dataset shows evidence of being nonrandom and nonlinear, thus a dynamical systems approach is taken. Classification and authentication accuracies are obtained under various representations of the monthly Bitcoin samples: outgoing transactions, as well as both outgoing and incoming transactions are considered, along with the timing and dynamic network properties of transaction sequences. The most appropriate representations of monthly Bitcoin samples are proposed. Results show an inherent lack of anonymity by exploiting patterns in long-term transactional behavior.

  20. IEEE Prize for Lucio Rossi

    CERN Multimedia

    2007-01-01

    Lucio Rossi receives his prize from John Spargo, Chairman of the IEEE Council on Superconductivity (left), and Martin Nisenoff, Chairman of the Council on Superconductivity’s Awards Committee (right). (Photo: IEEE Council on Superconductivity)With the magnets installed in the tunnel and work on the interconnections almost completed, Lucio Rossi has reaped the rewards of fifteen years of work. And yet, when the physicist from Milan arrived to take charge of the group responsible for the superconducting magnets in 2001, success seemed far from assured. Endowed with surprising levels of energy, Lucio Rossi, together with his team, ensured that production of these highly complex magnets got underway. Today, that achievement earns them the recognition not only of CERN but also of the international superconducting community. It is for this achievement that Lucio Rossi was awarded the prize by the IEEE’s (Institute of Electrical an...

  1. Leasing transactions

    Directory of Open Access Journals (Sweden)

    Radmila Presová

    2010-01-01

    Full Text Available The paper describes trade operations in lea­sin­g companies as specific businesses enabling acquisition of possession by legal and physical persons by gradual repayments of the purchase price. On a diagram it shows the complexity of business relations between the main participants of a lea­sin­g transaction, which are production companies, lea­sin­g companies and those interested in the subject of lea­sin­g. To capture the complexity of relations, there are also included all other participants. Their function in a lea­sin­g transaction starts only at the moment, when the leaseholders are not able to pay their liabilities to which they agreed in the innominate contract. Paper clarifies the term “lea­sin­g with zero mark-up”. With the help of calculation it describes the basis of a lea­sin­g transaction, where significantly participates also the production company, insurance company and commercial bank. All these subjects have certain benefits from a realized transaction. These are enabled by their close business relationships with the lea­sin­g company, which is sufficiently clear from the diagram and it is also substantiated by calculations. Paper includes a definition of lea­sin­g operations, as well as a ma­the­ma­ti­cal model of lea­sin­g payments calculation for a car. A part of the paper is also dealing with a cession of a lea­sin­g contract in the person of a leaseholder as a specific case enforced by financial issues of the leaseholder. The paper elaborates alternatives of evaluating client’s bonding capacity with the help of financial indicators.

  2. Coexistence of IEEE 802.11b/g WLANs and IEEE 802.15.4 WSNs: Modeling and Protocol Enhancements

    OpenAIRE

    Yuan, W.

    2011-01-01

    As an emerging short-range wireless technology, IEEE 802.15.4/ZigBee Wireless Sensor Networks (WSNs) are increasingly used in the fields of home control, industrial control, consumer electronics, energy management, building automation, telecom services, personal healthcare, etc. IEEE 802.15.4/Zig-Bee WSNs share the same 2.4 GHz license-free Industrial, Scientific, and Medical (ISM) band with many other wireless systems such as IEEE 802.11b/g WLANs, Bluetooth, cordless phones, etc. Due to the ...

  3. Remedial transactions curtailment via optimization

    Directory of Open Access Journals (Sweden)

    Maksimović Viktor

    2009-01-01

    Full Text Available The new method developed in this paper is aiming at transmission congestion management (CM. The new, Optimal Transactions Management method (OTM, is based on linear programming (LP, DC load flow (DCLF and linear security constraints. The OTM method is embedded in Available Transfer Capabilities (ATCs and Power Transfer Distribution Factors (PTDFs definitions' environment. Well-suited for both preventive and corrective modes of operation, the OTM method aids transmission system operator in running a congested power system network, where congestions are due to transactions. Potential congestion threat is solved by finding the 'culprit' transaction and its optimal reduction. Besides the proposed downsizing of scheduled and/or committed transactions, controls of the OTM method also include redispatching of generation and load levels. The task is to establish a system state without constraint violations. To ensure the feasible network solution, both DC and AC power flows are used. The common 5 nodes/7 lines Ward&Hale sample power system is used to clarify the OTM method. Besides, six other power system networks including the real-life power system network of Serbia, Macedonia and Montenegro (part of the South East Europe - SEE grid are used to test remedial potentials and CPU-time performances of the method. The 24-hour daily demand diagram is used with all test networks to study the effects of transactions as they are being superimposed to the regional grid. The remedial, transactions-curtailing OTM method is found well suited for market-related analyses precluding the hour-ahead, the day-ahead dispatch, as well as the real-time generation dispatch. It could also suit for the novel, Day Ahead Congestion Forecast (DACF procedure used in power markets. .

  4. Optimal Rescheduling of Generators for Congestion Management and Benefit Maximization in a Decentralized Bilateral Multi-transactions Power Network

    Science.gov (United States)

    Singh, Brijesh; Mahanty, Ranjit; Singh, S. P.

    2013-05-01

    This paper presents a framework to achieve an optimal power flow solution in a decentralized bilateral multitransaction-based market. An independent optimal dispatch solution has been used for each market. The interior point (IP)-based optimization technique has been used for finding a global economic optimal solution of the whole system. In this method, all the participants try to maximize their own profits with the help of system information announced by the operator. In the present work, a parallel algorithm has been used to find out a global optimum solution in decentralized market model. The study has been carried out on a modified IEEE-30 bus system. The results show that the suggested decentralized approach can provide a better optimal solution. The obtained results show the effectiveness of IP optimization-based optimal generator schedule and congestion management in the decentralized market.

  5. Ieee 802.15.4 Implementation on an Embedded Device

    OpenAIRE

    Thandee, Rithirong

    2012-01-01

    Software Defined Radio (SDR) is a growing technology that allows radio communication to become interoperable. SDR can lower the cost for a particular hardware radio to commu- nicate with another radio that uses a different standard. In order to show the capability of SDR, this thesis shows how to implement IEEE 802.14.5, a low-rate wireless personal area network (LR-WPAN) standard, on a standalone embedded machine. The implementation is done using a universal software radio pe...

  6. IEEE WEA 2012 - Mejores Trabajos

    Directory of Open Access Journals (Sweden)

    Miguel Alberto Melgarejo Rey

    2013-06-01

    Full Text Available El 2012 Workshop on Engineering Applications (WEA 2012 realizado porla Facultad de Ingeniería de la Universidad Distrital Francisco José deCaldas y su rama estudiantil IEEE (Institute for Electrical and ElectronicsEngineers, del 2 al 4 de mayo de 2012, fue un espacio académico dondeconvergieron academia e industria alrededor de áreas tan diversas comoel control, las comunicaciones, la electrónica de potencia, el procesamientode señales entre otras .A pesar de ser la primera edición delWEA, esta se caracterizó por una nutrida participación, se recibieron 69artículos, 49 provenientes de Colombia y 20 de otros países.

  7. The topology of card transaction money flows

    Science.gov (United States)

    Zanin, Massimiliano; Papo, David; Romance, Miguel; Criado, Regino; Moral, Santiago

    2016-11-01

    Money flow models are essential tools to understand different economical phenomena, like saving propensities and wealth distributions. In spite of their importance, most of them are based on synthetic transaction networks with simple topologies, e.g. random or scale-free ones, as the characterisation of real networks is made difficult by the confidentiality and sensitivity of money transaction data. Here, we present an analysis of the topology created by real credit card transactions from one of the biggest world banks, and show how different distributions, e.g. number of transactions per card or amount, have nontrivial characteristics. We further describe a stochastic model to create transactions data sets, feeding from the obtained distributions, which will allow researchers to create more realistic money flow models.

  8. Performance Analysis of the IEEE 802.11s PSM

    Directory of Open Access Journals (Sweden)

    Mirza Nazrul Alam

    2012-01-01

    Full Text Available With the introduction of IEEE 802.11 power save mode (PSM, a lot of work has been done to enhance the energy saving ability of the wireless nodes. The ultimate goal of the research is to make the networking equipment carbon neutral and prolong the lifetime of the energy limited device for various applications; in some cases it is a trade-off between energy efficiency and delay. However, few studies have been made until now in the area of IEEE 802.11s based link specific power mode. The essence of this method is the ability of a node to maintain different power modes with its different peer nodes at the same time. A new peer service period (PSP mechanism is also proposed in IEEE 802.11s amendment for transmitting to a receiver operating in PSM. In this paper the performance of the link specific power mode is studied for a single- and a multilink network in terms of energy, delay throughput, and sleep duration. It is found that at small load the energy saving could be as high as eighty percent when compared with the active mode operation. A stochastic model, based on discrete time discrete state Markov chain, is developed for one peer link operation to study the system behavior closely during PSM operation.

  9. Proceedings of IEEE Machine Learning for Signal Processing Workshop XVI

    DEFF Research Database (Denmark)

    Larsen, Jan

    These proceedings contains refereed papers presented at the sixteenth IEEE Workshop on Machine Learning for Signal Processing (MLSP'2006), held in Maynooth, Co. Kildare, Ireland, September 6-8, 2006. This is a continuation of the IEEE Workshops on Neural Networks for Signal Processing (NNSP......). The name of the Technical Committee, hence of the Workshop, was changed to Machine Learning for Signal Processing in September 2003 to better reflect the areas represented by the Technical Committee. The conference is organized by the Machine Learning for Signal Processing Technical Committee...... the same standard as the printed version and facilitates the reading and searching of the papers. The field of machine learning has matured considerably in both methodology and real-world application domains and has become particularly important for solution of problems in signal processing. As reflected...

  10. The IEEE Milestone event at CERN

    CERN Multimedia

    2005-01-01

    On the initiative of its French and Swiss Sections, the IEEE has honoured CERN with an 'IEEE Milestone in the history of electricity and electronics' for the invention of the multi-wire proportional chamber in 1968. The IEEE established the Electrical Engineering Milestones programe in 1983 to honour significant achievements in the history of electrical and electronics engineering. To be designated, an achievement must be at least 25 years old, must have involved a unique solution to an engineering problem, and must have had at least regional impact. Currently there are more than  50 IEEE Milestones around the world. http://www.ieee.org/organizations/history_center/cern.html The installation and unveiling of this IEEE Milestone will provide the opportunity to emphasize the close relationship between science, technology, industry and well-being in society.  A ceremony, organised with the support of a group of IEEE members working at CERN, will be held at the CERN Globe of Science and Inn...

  11. IEEE 802.11 Wireless LAN Security White Paper

    Energy Technology Data Exchange (ETDEWEB)

    King, J

    2001-10-22

    Given the increased productivity and growing popularity of wireless communications in general, and wireless data communications in particular, this paper outlines the protocols, security implications, and architectures of IEEE Std. 802.11-1999 wireless LANs (WLANs) and makes recommendations regarding a phased implementation of WLANs at LLNL. This project is driven by the need for convenient and secure access to the Internet for Laboratory visitors and to the internal network for Laboratory employees. A solid architecture designed with a priority on security will allow LLNL to offer network access in areas where it is traditionally hard to deploy wired networks. It will also enable such services as wireless access for inventory control and convenient network access for conference rooms around LLNL. Wireless network access has the potential to increase productivity by enabling instant access to information.

  12. CERN receives prestigious Milestone recognition from IEEE

    CERN Multimedia

    2005-01-01

    At a ceremony at CERN, Mr W. Cleon Anderson, President of the Institute of Electrical and Electronics Engineers (IEEE) formally a Milestone plaque in recognition of the invention of electronic particle detectors at CERN

  13. Throughput Analysis Model for IEEE 802.11e EDCA with Multiple Access Categories

    Directory of Open Access Journals (Sweden)

    Y. Lee

    2013-08-01

    Full Text Available IEEE 802.11e standard has been specified to support differentiated quality of service (QoS, one of the critical issues on the conventional IEEE 802.11 wireless local area networks (WLANs. Enhanced Distributed Channel Access (EDCA is the fundamental and mandatory contention-based channel access method of IEEE 802.11e, and delivers traffic based on differentiated Access Categories (ACs. A general three dimensional Markov chain model of IEEE 802.11e EDCA for performance analysis is proposed in this paper. The analytical model considers multiple stations with an arbitrary number of different ACs. It also differentiates the contention window (CW sizes and the arbitration interframe spaces (AIFSs, and considers virtual collision mechanism. Based on the model, the saturation throughput of EDCA is derived, and the accuracy of the proposed model is validated via simulations.

  14. Design, Verification and Application of IEEE 1687

    OpenAIRE

    Ghani Zadegan, Farrokh; Larsson, Erik; Jutman, Artur; Devadze, Sergei; Krenz-Baath, René

    2014-01-01

    IEEE 1687 (IJTAG) has been developed to enable flexible and automated access to the increasing number of embedded instruments in today's integrated circuits. These instruments enable efficient post-silicon validation, debugging, wafer sort, package test, burn-in, bring-up and manufacturing test of printed circuit board assemblies, power-on self-test, and in-field test. Current paper presents an overview of challenges as well as selected examples in the following topics around IEEE 1687 ne...

  15. Optimized tuning of contention window for IEEE 802.11 WLAN

    African Journals Online (AJOL)

    Department of Computer Science and Engineering, National Institute of Technology, Tiruchirappalli, INDIA ... Abstract. In wireless networks, the size of Contention Window (CW) plays a vital role as it changes the throughput and delay of the networks ..... Applications, IEEE/ACS International Conference, AICCSA 2008, pp.

  16. Theatrical distribution and P2P movie piracy: a survey of P2P networks in Hungary using transactional data

    NARCIS (Netherlands)

    Bodó, B.; Lakatos, Z.

    2012-01-01

    This article examines what appears to be the most important factor shaping file sharing: the failure of traditional cultural markets to efficiently supply the demand in the online environment. Its findings are based on tracking the traffic of movies on three Hungarian P2P networks. This dataset is

  17. Managerial accounting for transaction costs

    OpenAIRE

    Лабынцев, Николай Тихонович

    2015-01-01

    Essence and significance of transaction accounting and its basic concepts – transaction and transaction costs – have been determined. Main types of transaction costs and elements of transaction accounting for expenses have been considered. Source documents forms for the purpose of accounting for transaction costs have been worked out.

  18. A trans-acting locus regulates an anti-viral expression network and type 1 diabetes risk

    Czech Academy of Sciences Publication Activity Database

    Heinig, M.; Petretto, E.; Wallace, C.; Bottolo, L.; Rotival, M.; Lu, H.; Li, Y.; Sarwar, R.; Langley, S. R.; Bauerfeind, A.; Hummel, O.; Lee, Y. A.; Paskas, S.; Rintisch, C.; Saar, K.; Cooper, J.; Buchan, R.; Gray, C. C.; Cyster, J. G.; Erdmann, J.; Hengstenberg, C.; Maouche, S.; Ouwehand, W. H.; Rice, C. M.; Samani, N. J.; Schunkert, H.; Goodall, A. H.; Schulz, H.; Roider, H. G.; Vingron, M.; Blankenberg, S.; Münzel, T.; Zeller, T.; Szymczak, S.; Ziegler, A.; Tiret, L.; Smyth, D. J.; Pravenec, Michal; Aitman, T. J.; Cambien, F.; Clayton, D.; Todd, J. A.; Hubner, N.; Cook, S.A.

    2010-01-01

    Roč. 467, č. 7314 (2010), s. 460-464 ISSN 0028-0836 R&D Projects: GA MŠk(CZ) 1M0520; GA ČR GAP301/10/0290 Institutional research plan: CEZ:AV0Z50110509 Keywords : IRF7 driven inflammatory network * Ebi2 * type 1 diabetes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 36.101, year: 2010

  19. IEEE International Symposium on Biomedical Imaging.

    Science.gov (United States)

    2017-01-01

    The IEEE International Symposium on Biomedical Imaging (ISBI) is a scientific conference dedicated to mathematical, algorithmic, and computational aspects of biological and biomedical imaging, across all scales of observation. It fosters knowledge transfer among different imaging communities and contributes to an integrative approach to biomedical imaging. ISBI is a joint initiative from the IEEE Signal Processing Society (SPS) and the IEEE Engineering in Medicine and Biology Society (EMBS). The 2018 meeting will include tutorials, and a scientific program composed of plenary talks, invited special sessions, challenges, as well as oral and poster presentations of peer-reviewed papers. High-quality papers are requested containing original contributions to the topics of interest including image formation and reconstruction, computational and statistical image processing and analysis, dynamic imaging, visualization, image quality assessment, and physical, biological, and statistical modeling. Accepted 4-page regular papers will be published in the symposium proceedings published by IEEE and included in IEEE Xplore. To encourage attendance by a broader audience of imaging scientists and offer additional presentation opportunities, ISBI 2018 will continue to have a second track featuring posters selected from 1-page abstract submissions without subsequent archival publication.

  20. CERN receives prestigious Milestone recognition from IEEE

    CERN Multimedia

    2005-01-01

    The Nobel prize winner Georges Charpak and W. Cleon Anderson, IEEE President, unveil the Milestone bronze plaques. At a ceremony on 26 September at the Globe of Science and Innovation, Mr W. Cleon Anderson, President of the Institute of Electrical and Electronics Engineers (IEEE) formally dedicated Milestone plaques recognising the invention of electronic particle detectors at CERN. The plaque were unveiled by Mr Anderson and Georges Charpak, the Nobel-prize winning inventor of wire chamber technology at CERN in 1968. The IEEE is the world's largest professional association dedicated to the advancement of technology with 365,000 individual members in over 150 countries. Established in 1983, there are currently over 60 Milestones around the world. They honour momentous achievements in the history of electrical and electronics engineering, such as the landing of the first transatlantic cable, code breaking at Bletchley Park during World War II, and the development of the Japanese Bullet train, the Tokaido Shin...

  1. IEEE 1451.2 based Smart sensor system using ADuc847

    Science.gov (United States)

    Sreejithlal, A.; Ajith, Jose

    IEEE 1451 standard defines a standard interface for connecting transducers to microprocessor based data acquisition systems, instrumentation systems, control and field networks. Smart transducer interface module (STIM) acts as a unit which provides signal conditioning, digitization and data packet generation functions to the transducers connected to it. This paper describes the implementation of a microcontroller based smart transducer interface module based on IEEE 1451.2 standard. The module, implemented using ADuc847 microcontroller has 2 transducer channels and is programmed using Embedded C language. The Sensor system consists of a Network Controlled Application Processor (NCAP) module which controls the Smart transducer interface module (STIM) over an IEEE1451.2-RS232 bus. The NCAP module is implemented as a software module in C# language. The hardware details, control principles involved and the software implementation for the STIM are described in detail.

  2. Throughput and delay analysis of IEEE 802.15.6-based CSMA/CA protocol.

    Science.gov (United States)

    Ullah, Sana; Chen, Min; Kwak, Kyung Sup

    2012-12-01

    The IEEE 802.15.6 is a new communication standard on Wireless Body Area Network (WBAN) that focuses on a variety of medical, Consumer Electronics (CE) and entertainment applications. In this paper, the throughput and delay performance of the IEEE 802.15.6 is presented. Numerical formulas are derived to determine the maximum throughput and minimum delay limits of the IEEE 802.15.6 for an ideal channel with no transmission errors. These limits are derived for different frequency bands and data rates. Our analysis is validated by extensive simulations using a custom C+ + simulator. Based on analytical and simulation results, useful conclusions are derived for network provisioning and packet size optimization for different applications.

  3. Evaluating Transactive Controls of Integrated Transmission and Distribution Systems using the Framework for Network Co-Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Jacob; Edgar, Thomas W.; Daily, Jeffrey A.; Wu, Di

    2017-07-03

    With an ever-evolving power grid, concerns regarding how to maintain system stability, efficiency, and reliability remain constant because of increasing uncertainties and decreasing rotating inertia. To alleviate some of these concerns, demand response represents a viable solution and is virtually an untapped resource in the current power grid. This work describes a hierarchical control framework that allows coordination between distributed energy resources and demand response. This control framework is composed of two control layers: a coordination layer that ensures aggregations of resources are coordinated to achieve system objectives and a device layer that controls individual resources to assure the predetermined power profile is tracked in real time. Large-scale simulations are executed to study the hierarchical control, requiring advancements in simulation capabilities. Technical advancements necessary to investigate and answer control interaction questions, including the Framework for Network Co-Simulation platform and Arion modeling capability, are detailed. Insights into the interdependencies of controls across a complex system and how they must be tuned, as well as validation of the effectiveness of the proposed control framework, are yielded using a large-scale integrated transmission system model coupled with multiple distribution systems.

  4. Visualizing Dynamic Bitcoin Transaction Patterns

    Science.gov (United States)

    McGinn, Dan; Birch, David; Akroyd, David; Molina-Solana, Miguel; Guo, Yike; Knottenbelt, William J.

    2016-01-01

    Abstract This work presents a systemic top-down visualization of Bitcoin transaction activity to explore dynamically generated patterns of algorithmic behavior. Bitcoin dominates the cryptocurrency markets and presents researchers with a rich source of real-time transactional data. The pseudonymous yet public nature of the data presents opportunities for the discovery of human and algorithmic behavioral patterns of interest to many parties such as financial regulators, protocol designers, and security analysts. However, retaining visual fidelity to the underlying data to retain a fuller understanding of activity within the network remains challenging, particularly in real time. We expose an effective force-directed graph visualization employed in our large-scale data observation facility to accelerate this data exploration and derive useful insight among domain experts and the general public alike. The high-fidelity visualizations demonstrated in this article allowed for collaborative discovery of unexpected high frequency transaction patterns, including automated laundering operations, and the evolution of multiple distinct algorithmic denial of service attacks on the Bitcoin network. PMID:27441715

  5. Visualizing Dynamic Bitcoin Transaction Patterns.

    Science.gov (United States)

    McGinn, Dan; Birch, David; Akroyd, David; Molina-Solana, Miguel; Guo, Yike; Knottenbelt, William J

    2016-06-01

    This work presents a systemic top-down visualization of Bitcoin transaction activity to explore dynamically generated patterns of algorithmic behavior. Bitcoin dominates the cryptocurrency markets and presents researchers with a rich source of real-time transactional data. The pseudonymous yet public nature of the data presents opportunities for the discovery of human and algorithmic behavioral patterns of interest to many parties such as financial regulators, protocol designers, and security analysts. However, retaining visual fidelity to the underlying data to retain a fuller understanding of activity within the network remains challenging, particularly in real time. We expose an effective force-directed graph visualization employed in our large-scale data observation facility to accelerate this data exploration and derive useful insight among domain experts and the general public alike. The high-fidelity visualizations demonstrated in this article allowed for collaborative discovery of unexpected high frequency transaction patterns, including automated laundering operations, and the evolution of multiple distinct algorithmic denial of service attacks on the Bitcoin network.

  6. High Availability Transactions

    OpenAIRE

    Kolltveit, Heine

    2005-01-01

    This thesis presents a framework of a passively replicated transaction manager. By integrating transactions and replication, two well known fault tolerance techniques, the framework provides high availability for transactional systems and better support for non-deterministic execution for replicated systems. A prototype Java implementation of the framework, based on Jgroup/ARM and Jini, has been developed and performance tests have been executed. The results indicate that the response time fo...

  7. Inertial Motion Tracking for Inserting Humans into a Networked Synthetic Environment

    Science.gov (United States)

    2007-08-31

    magnetic sensors package,” IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 12, no. 2, pp. 295–302, June 2004. [11] E...Transactions On Neural Systems And Rehabilitation Engineering, Vol. 13, No. 3, September 2005. 1216 IEEE TRANSACTIONS ON ROBOTICS, VOL. 22, NO. 6...noise. Mechanical tracking systems can be placed in two separate categories. Body-based systems use an exoskeleton that is at- tached to the

  8. The IEEE Software Engineering Standards Process

    Science.gov (United States)

    Buckley, Fletcher J.

    1984-01-01

    Software Engineering has emerged as a field in recent years, and those involved increasingly recognize the need for standards. As a result, members of the Institute of Electrical and Electronics Engineers (IEEE) formed a subcommittee to develop these standards. This paper discusses the ongoing standards development, and associated efforts.

  9. IEEE Standard for Floating Point Numbers

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 1. IEEE Standard for Floating Point Numbers. V Rajaraman. General Article Volume 21 Issue 1 January 2016 pp 11-30. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/021/01/0011-0030. Keywords.

  10. The IEEE 802.11a standards

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. The IEEE 802.11a standards. Provides higher data rate and system capacities and uses OFDM in Physical Layer to mitigate the multi path effects;. Supports multiple 20Mhz channel. Each channel being an OFDM Modulated;; 52 Carriers. 48 data carrier; 4 Carry pilot ...

  11. Performance Evaluations for IEEE 802.15.4-based IoT Smart Home Solution

    Directory of Open Access Journals (Sweden)

    Nga Dinh

    2016-09-01

    Full Text Available The Internet of Things (IoT is going to be a market-changing force for a variety of real-time applications such as e-healthcare, home automation, environmental monitoring, and industrial automation. Low power wireless communication protocols offering long lifetime and high reliability such as the IEEE 802.15.4 standard have been a key enabling technology for IoT deployments and are deployed for home automation recently. The issues of the IEEE 802.15.4 networks have moved from theory to real world deployments. The work presented herein intends to demonstrate the use of the IEEE 802.15.4 standard in recent IoT commercial products for smart home applications: the Smart Home Starter Kit. The contributions of the paper are twofold. First, the paper presents how the IEEE 802.15.4 standard is employed in Smart Home Starter Kit. In particular, network topology, network operations, and data transfer mode are investigated. Second, network performance metrics such as end-to-end (E2E delay and frame reception ratio (FRR are evaluated by experiments. In addition, the paper discusses several directions for future improvements of home automation commercial products.

  12. Evaluation of the Effects of Hidden Node Problems in IEEE 802.15.7 Uplink Performance.

    Science.gov (United States)

    Ley-Bosch, Carlos; Alonso-González, Itziar; Sánchez-Rodríguez, David; Ramírez-Casañas, Carlos

    2016-02-06

    In the last few years, the increasing use of LEDs in illumination systems has been conducted due to the emergence of Visible Light Communication (VLC) technologies, in which data communication is performed by transmitting through the visible band of the electromagnetic spectrum. In 2011, the Institute of Electrical and Electronics Engineers (IEEE) published the IEEE 802.15.7 standard for Wireless Personal Area Networks based on VLC. Due to limitations in the coverage of the transmitted signal, wireless networks can suffer from the hidden node problems, when there are nodes in the network whose transmissions are not detected by other nodes. This problem can cause an important degradation in communications when they are made by means of the Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) access control method, which is used in IEEE 802.15.7 This research work evaluates the effects of the hidden node problem in the performance of the IEEE 802.15.7 standard We implement a simulator and analyze VLC performance in terms of parameters like end-to-end goodput and message loss rate. As part of this research work, a solution to the hidden node problem is proposed, based on the use of idle patterns defined in the standard. Idle patterns are sent by the network coordinator node to communicate to the other nodes that there is an ongoing transmission. The validity of the proposed solution is demonstrated with simulation results.

  13. IEEE 802.11e (EDCA analysis in the presence of hidden stations

    Directory of Open Access Journals (Sweden)

    Xijie Liu

    2011-07-01

    Full Text Available The key contribution of this paper is the combined analytical analysis of both saturated and non-saturated throughput of IEEE 802.11e networks in the presence of hidden stations. This approach is an extension to earlier works by other authors which provided Markov chain analysis to the IEEE 802.11 family under various assumptions. Our approach also modifies earlier expressions for the probability that a station transmits a packet in a vulnerable period. The numerical results provide the impact of the access categories on the channel throughput. Various throughput results under different mechanisms are presented.

  14. Integrity in Transactional Leadership

    Science.gov (United States)

    Miller, Thomas

    2011-01-01

    This chapter begins with a discussion of the impact of limited resources on the integrity of transactions between students and student affairs administrators. A framework and guiding principles for maintaining integrity are offered, and then some general principles for transactions with students are presented. Next, the chapter involves integrity…

  15. Structure and Anonymity of the Bitcoin Transaction Graph

    Directory of Open Access Journals (Sweden)

    Kay Hamacher

    2013-05-01

    Full Text Available The Bitcoin network of decentralized payment transactions has attracted a lot of attention from both Internet users and researchers in recent years. Bitcoin utilizes a peer-to-peer network to issue anonymous payment transactions between different users. In the currently used Bitcoin clients, the full transaction history is available at each node of the network to prevent double spending without the need for a central authority, forming a valuable source for empirical research on network structure, network dynamics, and the implied anonymity challenges, as well as guidance on the future evolution of complex payment systems. We found dynamical effects of which some increase anonymity while others decrease it. Most importantly, several parameters of the Bitcoin transaction graph seem to have become stationary over the last 12–18 months. We discuss the implications.

  16. Adaptive, Tactical Mesh Networking: Control Base MANET Model

    Science.gov (United States)

    2010-09-01

    pp. 316–320 Available: IEEE Xplore , http://ieeexplore.ieee.org [Accessed: June 9, 2010]. [5] N. Sidiropoulos, “Multiuser Transmit Beamforming...Mobile Mesh Segments of TNT Testbed .......... 11 Figure 5. Infrastructure and Ad Hoc Mode of IEEE 802.11................................ 13 Figure...6. The Power Spectral Density of OFDM................................................ 14 Figure 7. A Typical IEEE 802.16 Network

  17. A Comprehensive Taxonomy and Analysis of IEEE 802.15.4 Attacks

    Directory of Open Access Journals (Sweden)

    Yasmin M. Amin

    2016-01-01

    Full Text Available The IEEE 802.15.4 standard has been established as the dominant enabling technology for Wireless Sensor Networks (WSNs. With the proliferation of security-sensitive applications involving WSNs, WSN security has become a topic of great significance. In comparison with traditional wired and wireless networks, WSNs possess additional vulnerabilities which present opportunities for attackers to launch novel and more complicated attacks against such networks. For this reason, a thorough investigation of attacks against WSNs is required. This paper provides a single unified survey that dissects all IEEE 802.15.4 PHY and MAC layer attacks known to date. While the majority of existing references investigate the motive and behavior of each attack separately, this survey classifies the attacks according to clear metrics within the paper and addresses the interrelationships and differences between the attacks following their classification. The authors’ opinions and comments regarding the placement of the attacks within the defined classifications are also provided. A comparative analysis between the classified attacks is then performed with respect to a set of defined evaluation criteria. The first half of this paper addresses attacks on the IEEE 802.15.4 PHY layer, whereas the second half of the paper addresses IEEE 802.15.4 MAC layer attacks.

  18. Radio Frequency Fingerprinting Techniques Through Preamble Modification in IEEE 802.11B

    Science.gov (United States)

    2014-06-30

    per second OFDM Orthogonal Frequency Division Multiplexing OSI Open Systems Interconnection PAN Personal Area Network PBCC Packet Binary Convolution...traffic. In addition, Section 2.5 also details preambles in 802.11, network synchronization and channel estimation . Section 2.6 introduces the...When these systems operate in monitor mode, they receive all IEEE 802.11 traffic, irrespective the operating channel . Consequently, these monitor

  19. A versatile trigger and synchronization module with IEEE1588 capabilities and Epics support

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, J.M.; Ruiz, M.; Borrego, J.; Arcas, G. de; Barrera, E. [Universidad Politecnica de Madrid, Grupo de Investigacion en Instrumentacion y Acustica Aplicada, Madrid (Spain); Vega, J. [Asociacion EURATOM/CIEMAT para Fusion. Madrid (Spain)

    2009-07-01

    Event timing and synchronization are two key aspects to improve the implementation of distributed data acquisition (dDAQ) systems such as the ones used in fusion experiments. It is very important to integrate dDAQ in control and measurement networks. This poster analyzes the applicability of the IEEE 1588 and EPICS standards to solve these problems, and presents a hardware module implementation based in both of them that allow adding these functionalities to any DAQ. The IEEE1588 standard facilitates the integration of event timing and synchronization mechanisms in distributed data acquisition systems based on IEEE 803.3 (Ethernet). An optimal implementation of such system requires the use of network interface devices which include specific hardware resources devoted to the IEE1588 functionalities. Unfortunately, this is not the approach followed in most of the large number of applications available nowadays. Therefore, most solutions are based in software and use standard hardware network interfaces. This paper presents the development of a hardware module (GI2E) with IEEE 1588 capabilities which includes USB, RS232, RS485 and CAN interfaces. This permits the integration of any DAQ element that uses these interfaces in dDAQ systems in an efficient and simple way. The module has been developed with Motorola's Coldfire MCF5234 processor and National Semiconductors's PHY DP83640T, providing it with the possibility to implement the PTP protocol of IEEE 1588 by hardware, and therefore increasing its performance over other implementations based in software. To facilitate the integration of the dDAQ system in control and measurement networks the module includes a basic IOC (Input Output Controller) functionality of the EPICS (Experimental Physics and Industrial Control System) architecture. This document is a poster. (authors)

  20. A versatile trigger and synchronization module with IEEE1588 capabilities and EPICS support

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, J.M., E-mail: juanmanuel.lopez@upm.e [Grupo de Investigacion en Instrumentacion y Acustica Aplicada, Universidad Politecnica de Madrid, Crta. Valencia Km-7, Madrid 28031 (Spain); Ruiz, M.; Borrego, J.; Arcas, G. de; Barrera, E. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada, Universidad Politecnica de Madrid, Crta. Valencia Km-7, Madrid 28031 (Spain); Vega, J. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain)

    2010-07-15

    Event timing and synchronization are two key aspects to improve in the implementation of distributed data acquisition (dDAQ) systems such as the ones used in fusion experiments. It is also of great importance the integration of dDAQ in control and measurement networks. This paper analyzes the applicability of the IEEE1588 and EPICS standards to solve these problems, and presents a hardware module implementation based in both of them that allow adding these functionalities to any DAQ. The IEEE1588 standard facilitates the integration of event timing and synchronization mechanisms in distributed data acquisition systems based on IEEE 803.3 (Ethernet). An optimal implementation of such system requires the use of network interface devices which include specific hardware resources devoted to the IEE1588 functionalities. Unfortunately, this is not the approach followed in most of the large number of applications available nowadays. Therefore, most solutions are based in software and use standard hardware network interfaces. This paper presents the development of a hardware module (GI2E) with IEEE1588 capabilities which includes USB, RS232, RS485 and CAN interfaces. This permits to integrate any DAQ element that uses these interfaces in dDAQ systems in an efficient and simple way. The module has been developed with Motorola's Coldfire MCF5234 processor and National Semiconductors's PHY DP83640T, providing it with the possibility to implement the PTP protocol of IEEE1588 by hardware, and therefore increasing its performance over other implementations based in software. To facilitate the integration of the dDAQ system in control and measurement networks the module includes a basic Input/Output Controller (IOC) functionality of the Experimental Physics and Industrial Control System (EPICS) architecture. The paper discusses the implementation details of this module and presents its applications in advanced dDAQ applications in the fusion community.

  1. Governance structures for real estate transactions: Markets ...

    African Journals Online (AJOL)

    This article examines the relative prevalence of markets, hierarchies and networks in the governance of real-estate transactions under three property rights regimes in Windhoek's low-income settlements. These governance structures are related to respective property rights regimes and to conjectures made about the ...

  2. The harmonics detection method based on neural network applied ...

    African Journals Online (AJOL)

    user

    caused by the ac component of the instantaneous real power. .... error signal, which is the difference of the injected current to the reference ... Smoothing inductor .... Real-time shunt active power filter compensation, IEEE Transactions on.

  3. Biometrics for home networks security

    KAUST Repository

    Ansari, Imran Shafique

    2009-01-01

    Hacking crimes committed to the home networks are increasing. Advanced network protection is not always possible for the home networks. In this paper we will study the ability of using biometric systems for authentication in home networks. ©2009 IEEE.

  4. Report of the 2017 IEEE Cyber Science and Technology Congress

    Directory of Open Access Journals (Sweden)

    Wenbing Zhao

    2017-12-01

    Full Text Available The modern digitized world has led to the emergence of a new paradigm on global information networks and infrastructures known as Cyberspace and the studies of Cybernetics, which bring seamless integration of physical, social and mental spaces. Cyberspace is becoming an integral part of our daily life from learning and entertainment to business and cultural activities. As expected, this whole concept of Cybernetics brings new challenges that need to be tackled. The 2017 IEEE Cyber Science and Technology Congress (CyberSciTech 2017 provided a forum for researchers to report their research findings and exchange ideas. The congress took place in Orlando, Florida, USA during 6–10 November 2017. Not counting poster papers, the congress accepted over fifty papers that are divided into nine sessions. In this report, we provide an overview of the research contributions of the papers in CyberSciTech 2017.

  5. Dynamic Vehicle Routing for Robotic Networks (Workshop Briefing Charts)

    Science.gov (United States)

    2010-06-29

    Traveling Salesperson Problems for the Dubins vehicle. IEEE Transactions on Automatic Control, 53(6):1378–1391, 2008 2 K. Savla, F. Bullo, and E. Frazzoli...Traveling Salesperson Problems for a double integrator. IEEE Transactions on Automatic Control, 54(4):788–793, 2009 3 J. J. Enright, K. Savla, E...29jun10 @ Baltimore, ACC 1 / 36 Outline of the lecture 1 Models of vehicles with differential constraints 2 Traveling salesperson problems 3 The

  6. A Fast MAC-Layer Handover for an IEEE 802.16e-Based WMAN

    Science.gov (United States)

    Ray, Sayan K.; Pawlikowski, Krzysztof; Sirisena, Harsha

    We propose a modification of the IEEE 802.16e hard handover (HHO) procedure, which significantly reduces the handover latency constraint of the original HHO procedure in IEEE 802.16e networks. It allows a better handling of the delay-sensitive traffic by avoiding unnecessary time-consuming scanning and synchronization activity as well as simplifies the network re-entry procedure. With the help of the backhaul network, it reduces the number of control messages in the original handover policy, making the handover latency acceptable also for real-time streaming traffic. Preliminary performance evaluation studies show that the modified handover procedure is able to reduce the total handover latency by about 50%.

  7. Bitcoin Transaction Graph Analysis

    OpenAIRE

    Fleder, Michael; Kester, Michael S; Pillai, Sudeep

    2015-01-01

    Bitcoins have recently become an increasingly popular cryptocurrency through which users trade electronically and more anonymously than via traditional electronic transfers. Bitcoin's design keeps all transactions in a public ledger. The sender and receiver for each transaction are identified only by cryptographic public-key ids. This leads to a common misconception that it inherently provides anonymous use. While Bitcoin's presumed anonymity offers new avenues for commerce, several recent st...

  8. Applying IEEE storage system management standards at the National Storage Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Louis, S.; Hyer, S.W.

    1992-12-04

    Since its inception in 1990, the IEEE Storage System Standards Working Group has identified storage-system management as an area in need of further development The pressing need for standards in storage-system management arises from the requirement to exchange management information and to provide control in a consistent predictable manner between the components of a storage system. An appropriate set of management standards will allow multiple vendors to supply storage management subsystems or applications that are integral to or compatible with new storage systems conforming to future IEEE standards. An early, practical application of IEEE storage-system-management work is being pursued at the National Storage Laboratory (NSL), a recently-formed industrial collaboration at Lawrence Livermore National Laboratory. The NSL`s purpose is to develop advanced hardware and software technologies for high-performance, distributed storage systems. Since storage system management is of critical concern, it is being explored in depth at the NSL. Work was initiated to define basic management requirements and develop generalized graphical-user-interface tools using remote-procedure-call mechanisms to implement the NSL`s conceptual management framework. Several constraints were imposed on the development of early versions of this work to maintain compatibility with the NSL`s underlying UniTree-based software architecture and to provide timely prototypes and proof of concept. The project leverages the on-going standards work of the IEEE Storage System Standards Working Group (SSSWG) and also explores some of the relationships and interactions between IEEE storage-system management and more well known management methods for distributed systems and networks. It will have long term benefits by providing ``real-life`` storage-system-management requirements to the IEEE SSSWG for validation of evolving standards.

  9. Valuation of Transactive Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hammerstrom, Donald J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Corbin, Charles D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fernandez, Nicholas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Homer, Juliet S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Makhmalbaf, Atefe [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pratt, Robert G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Somani, Abhishek [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gilbert, Erik I. [Navigant Consulting, Boulder, CO (United States); Chandler, Shawn [Navigant Consulting, Portland, OR (United States); Shandross, Richard [Navigant Consulting, Burlington, MA (United States)

    2016-05-12

    This is a final report from a project funded by the U.S. Department of Energy to formulate and test a methodology for valuation of systems where transaction-based mechanisms coordinate the exchange of value between the system’s actors. Today, the principal commodity being exchanged is electrical energy, and such mechanisms are called transactive energy systems. The authors strove to lay a foundation for meaningful valuations of transactive systems in general, and transactive energy systems as a special case. The word valuation is used in many different ways. This report proposes a valuation methodology that is inclusive of many types of valuations. Many will be familiar with cost-benefit valuations, in which both costs and benefits are assessed to determine whether the assets are worth their cost. Another set of valuation methods attempt to optimize an outcome using available resources, as is the case with integrated resource planning. In the end, this report’s methodology was most influenced by and most resembles the integrated-resource-planning approach. Regardless, we wish to enforce the premise that all valuations are comparative and should clearly specify a baseline scenario. A long, annotated list of prior valuation studies and valuation methodologies that influenced this report has been appended to this report. Much research is being conducted today concerning transactive systems, but only a handful of transactive system mechanisms have been formulated and field tested. They are found to be quite diverse, and the documentation of the various mechanisms is uneven in breadth and quality. It is therefore not adequate to simply assert that a valuation scenario includes a transactive system; certain characteristics and qualities of the chosen transactive system mechanism must be defined and stated. The report lists and discusses most of the known transactive system mechanisms. It offers a set of questions that may be used to help specify important

  10. Six Methods of Transaction Visualization in Virtual Environments

    Energy Technology Data Exchange (ETDEWEB)

    WALTHER, ELEANOR A.; TRAHAN, MICHAEL W.; SUMMERS, KENNETH L.; EYRING, TIM; CAUDELL, THOMAS P.

    2002-06-01

    Many governmental and corporate organizations are interested in tracking materials and/or information through a network. Often, as in the case of the U.S. Customs Service, the traffic is recorded as transactions through a large number of checkpoints with a correspondingly complex network. These networks will contain large numbers of uninteresting transactions that act as noise to conceal the chains of transactions of interest, such as drug trafficking. We are interested in finding significant paths in transaction data containing high noise levels, which tend to make traditional graph visualization methods complex and hard to understand. This paper covers the evolution of a series of graphing methods designed to assist in this search for paths-from 1-D to 2-D to 3-D and beyond.

  11. Reliable Communication in Wireless Meshed Networks using Network Coding

    DEFF Research Database (Denmark)

    Pahlevani, Peyman; Paramanathan, Achuthan; Hundebøll, Martin

    2012-01-01

    The advantages of network coding have been extensively studied in the field of wireless networks. Integrating network coding with existing IEEE 802.11 MAC layer is a challenging problem. The IEEE 802.11 MAC does not provide any reliability mechanisms for overheard packets. This paper addresses th...... introduce some signaling overhead, the results show that the performance is yet improved....

  12. Hybrid Polling Method for Direct Link Communication for IEEE 802.11 Wireless LANs

    Directory of Open Access Journals (Sweden)

    Woo-Yong Choi

    2008-10-01

    Full Text Available The direct link communication between STAtions (STAs is one of the techniques to improve the MAC performance of IEEE 802.11 infrastructure networks. For the efficient direct link communication, in the literature, the simultaneous polling method was proposed to allow the multiple direct data communication to be performed simultaneously. However, the efficiency of the simultaneous polling method is affected by the interference condition. To alleviate the problem of the lower polling efficiency with the larger interference range, the hybrid polling method is proposed for the direct link communication between STAs in IEEE 802.11 infrastructure networks. By the proposed polling method, we can integrate the sequential and simultaneous polling methods properly according to the interference condition. Numerical examples are also presented to show the medium access control (MAC performance improvement by the proposed polling method.

  13. On Adaptive Contention Resolution Schemes for IEEE 802.16 BWA Systems

    Directory of Open Access Journals (Sweden)

    Deng Der-Jiunn

    2009-01-01

    Full Text Available According to the latest version of the IEEE 802.16 standard, the mandatory contention resolution method is the truncated binary exponential backoff, with the initial window size and the maximum window size controlled by the base station. However, the problem of choosing the right set of backoff parameters for the current network level remains unsolved and left as an open issue since this strategy might incur a high collision probability and the channel utilization could be degraded in congested scenario. In this paper, we propose two pragmatic adaptive algorithms, namely semi-dynamic and quasi-dynamic contention resolution schemes, that allow the base station to adjust its backoff window size based on current channel status. By controlling the size of backoff window according to varying network conditions, both schemes are able to achieve higher performance in comparison with the legacy IEEE 802.16 standard.

  14. Transactive control: a framework for operating power systems characterized by high penetration of distributed energy resources

    DEFF Research Database (Denmark)

    Hu, Junjie; Yang, Guangya; Kok, Koen

    2016-01-01

    The increasing number of distributed energy resources connected to power systems raises operational challenges for the network operator, such as introducing grid congestion and voltage deviations in the distribution network level, as well as increasing balancing needs at the whole system level......, followed by a literature review and demonstration projects that apply to transactive control. Cases are then presented to illustrate the transactive control framework. At the end, discussions and research directions are presented, for applying transactive control to operating power systems, characterized...

  15. A distributed scheme to manage the dynamic coexistence of IEEE 802.15.4-based health-monitoring WBANs.

    Science.gov (United States)

    Deylami, Mohammad N; Jovanov, Emil

    2014-01-01

    The overlap of transmission ranges between wireless networks as a result of mobility is referred to as dynamic coexistence. The interference caused by coexistence may significantly affect the performance of wireless body area networks (WBANs) where reliability is particularly critical for health monitoring applications. In this paper, we analytically study the effects of dynamic coexistence on the operation of IEEE 802.15.4-based health monitoring WBANs. The current IEEE 802.15.4 standard lacks mechanisms for effectively managing the coexistence of mobile WBANs. Considering the specific characteristics and requirements of health monitoring WBANs, we propose the dynamic coexistence management (DCM) mechanism to make IEEE 802.15.4-based WBANs able to detect and mitigate the harmful effects of coexistence. We assess the effectiveness of this scheme using extensive OPNET simulations. Our results indicate that DCM improves the successful transmission rates of dynamically coexisting WBANs by 20%-25% for typical medical monitoring applications.

  16. Resources and Transaction Costs

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2004-01-01

    resources depends on the propertyrights that she holds to those resources and on the transaction costs of exchanging,defining and protecting the relevant property rights. While transaction costs aremajor sources of value dissipation, value may be created by reducing suchdissipation. Implications for the RBV......AbstractThe economics of property rights furthers the resource-based view in a number ofways. Resource analysis is refined by conceptualizing resources as composed ofmultiple attributes to which property rights may be held. A resource owner's abilityto create, appropriate and sustain value from...

  17. Resources and transaction costs

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2005-01-01

    from resources depends on the property rights that he or she holds and on the transaction costs of exchanging, defining, and protecting them. While transaction costs are a major source of value dissipation, reducing such dissipation may create value. Implications for the RBV analysis of sustained......Property rights economics furthers the resource-based view of strategic management in a number of ways. First, resources are conceptualized as being composed of multiple attributes for which property rights may be held. Second, a resource owner's ability to create, appropriate, and sustain value...

  18. Value and Transaction Costs

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2003-01-01

    and capturing propertyrights. We clarify the key role of transaction costs with respect to understandingvalue creation and the limitations and opportunities of strategizing relative tocompetitive forces. The economics of property rights identifies new sources ofvalue creation (i.e., reducing the dissipation......AbstractWe forge linkages between the economics of property rights (Coase, Demsetz,Cheung, Barzel) and strategic management. Property rights to resources consistof the rights to consume, obtain income from, and alienate these resources.Transaction costs are the costs of exchanging, protecting...

  19. 7th IEEE International Conference Intelligent Systems

    CERN Document Server

    Atanassov, KT; Doukovska, L; Hadjiski, M; Jotsov, V; Kacprzyk, J; Kasabov, N; Sotirov, S; Szmidt, E; Zadrożny, S; Filev, D; Jabłkowski, J; Kacprzyk, J; Krawczak, M; Popchev, I; Rutkowski, L; Sgurev, V; Sotirova, E; Szynkarczyk, P

    2015-01-01

    This two volume set of books constitutes the proceedings of the 2014  7th IEEE International Conference Intelligent Systems (IS), or IEEE IS’2014 for short, held on September 24‐26, 2014 in Warsaw, Poland. Moreover, it contains some selected papers from the collocated IWIFSGN'2014-Thirteenth International Workshop on Intuitionistic Fuzzy Sets and Generalized Nets.The conference was organized by the Systems Research Institute, Polish Academy of Sciences, Department IV of Engineering Sciences, Polish Academy of Sciences, and Industrial Institute of Automation and Measurements - PIAP.The papers included in the two proceedings volumes have been subject to a thorough review process by three highly qualified peer reviewers.Comments and suggestions from them have considerable helped improve the quality of the papers but also the division of the volumes into parts, and assignment of the papers to the best suited parts.  

  20. FPGA implementation cost and performance evaluation of IEEE 802.11 protocol encryption security schemes

    Energy Technology Data Exchange (ETDEWEB)

    Sklavos, N; Selimis, G; Koufopavlou, O [Electrical and Computer Engineering Department, University of Patras, Patras (Greece)

    2005-01-01

    The explosive growth of internet and consumer demand for mobility has fuelled the exponential growth of wireless communications and networks. Mobile users want access to services and information, from both internet and personal devices, from a range of locations without the use of a cable medium. IEEE 802.11 is one of the most widely used wireless standards of our days. The amount of access and mobility into wireless networks requires a security infrastructure that protects communication within that network. The security of this protocol is based on the wired equivalent privacy (WEP) scheme. Currently, all the IEEE 802.11 market products support WEP. But recently, the 802.11i working group introduced the advanced encryption standard (AES), as the security scheme for the future IEEE 802.11 applications. In this paper, the hardware integrations of WEP and AES are studied. A field programmable gate array (FPGA) device has been used as the hardware implementation platform, for a fair comparison between the two security schemes. Measurements for the FPGA implementation cost, operating frequency, power consumption and performance are given.

  1. Utterance Generation for Transaction Dialogues

    NARCIS (Netherlands)

    Hulstijn, J.; van Hessen, Adrianus J.

    1998-01-01

    This paper discusses the utterance generation module of a spoken dialogue system for transactions. Transactions are interesting because they involve obligations of both parties: the system should provide all relevant information; the user should feel committed to the transaction once it has been

  2. Protecting Online Transactions with Unique Embedded Key Generators

    DEFF Research Database (Denmark)

    Boesgaard, Martin; Zenner, Erik

    2007-01-01

    We present a novel approach for protecting transactions over networks. While we use the example of a netbank application, the proposal is relevant for many security-critical transactions. The approach is based on two major changes compared to current solutions. The first one is the use of individ......We present a novel approach for protecting transactions over networks. While we use the example of a netbank application, the proposal is relevant for many security-critical transactions. The approach is based on two major changes compared to current solutions. The first one is the use...... of individualized key derivation functions, which ensure that given the same input, each copy of the application ends up with different keys. The second contribution is the individualizing of program copies by subtle code modification. This makes automated analysis and patching of a client-side application very...

  3. IEEE Standard Dictionary of Electrical and Electronics Terms.

    Science.gov (United States)

    Institute of Electrical and Electronics Engineers, Inc., New York, NY.

    This dictionary, prepared by the Institute of Electrical and Electronics Engineers, Inc. (IEEE), defines 13,000 technical words from every area of electrical and electronics engineering. The dictionary contains hundreds of new terms as well as revisions of earlier ones. Each definition is an official standard of IEEE. The definitions are arranged…

  4. IEEE International Workshop on Machine Learning for Signal Processing: Preface

    DEFF Research Database (Denmark)

    Tao, Jianhua

    The 21st IEEE International Workshop on Machine Learning for Signal Processing will be held in Beijing, China, on September 18–21, 2011. The workshop series is the major annual technical event of the IEEE Signal Processing Society's Technical Committee on Machine Learning for Signal Processing...

  5. Modelling Real Property Transactions

    DEFF Research Database (Denmark)

    Stubkjær, Erik

    2003-01-01

    Der er store forskelle i financieringsomkostningerne ved hussalg i forskellige lande. Er disse forskelle nødvendige? og kan udgifterne reduceres? Sådanne spørgsmål søger forskningsprojektet ?Modelling Real Property Transactions?, officielt sat i værk indenfor rammerne af COST (European Co...

  6. 5. Cash Transactions

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 4. Electronic Commerce-Cash Transactions. V Rajaraman. Series Article Volume 6 Issue 4 April 2001 pp 8-14. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/006/04/0008-0014. Author Affiliations.

  7. Perspectives on development of IEEE 1073: the Medical Information Bus (MIB) standard.

    Science.gov (United States)

    Kennelly, R J; Gardner, R M

    1997-08-01

    Automated data capture from bedside patient medical devices is now possible using a new Institute of Electrical and Electronic Engineering (IEEE) and American National Standards Institute (ANSI) Medical Information Bus (MIB) data communications standard (IEEE 1073). The first two standard documents, IEEE 1073.3.1 (Transportation Profile) and IEEE 1073.4.1 (Physical Layer), define the hardware protocol for bedside device communications. With the above noted IEEE MIB standards in place, hospitals can now start designing customized applications for acquiring data from bedside devices such as bedside monitors, i.v. pumps, ventilators, etc. for multiple purposes. The hardware 'plug and play' features of the MIB will enable nurses and physicians to establish communications with these devices simply and conveniently by plugging them into a bedside data connector. No other action will be necessary to establish identification of the device or communications with the device. Presently to connect bedside devices, technical help from hardware and software experts are required to establish such communications links. As a result of standardization of communications, it will be easy to establish a highly mobile network of bedside devices and more promptly and efficiently collect patient related data. Collection of data automatically should lead to the design of new medical computing applications that will tie in directly with the emerging mission and operations of hospitals. The MIB will permit acquisition of patient data more efficiently with greater accuracy, more completeness and more promptly. The above noted features are all essential to the development of computerized treatment protocols and should lead to improved quality of patient care. This manuscript provides the rational and historical overview of the development of the MIB standard.

  8. A GRAPH-BASED INVESTIGATION OF BITCOIN TRANSACTIONS

    OpenAIRE

    Zhao, Chen; Guan, Yong

    2015-01-01

    Part 2: INTERNET CRIME INVESTIGATIONS; International audience; The Bitcoin global cryptocurrency system has been the subject of several criminal cases. The Bitcoin network is a peer-to-peer system that has participants from all over the Internet. The Bitcoin protocol requires participating nodes to retain and update all transaction records; this ensures that all Bitcoin activities are accessible from a consistent transaction history database. This chapter describes a graph-based method for an...

  9. Distributed Control of Robotic Networks: A Mathematical Approach to Motion Coordination Algorithms

    Science.gov (United States)

    2008-10-27

    different, then the MST is unique; Traveling salesperson problem. A traveling salesperson tour (TSP) of G, denoted TTSP, is a cycle that passes through all...Analysis of Vicsek’s model, IEEE Transactions on Automatic Control, 49(6), 981–982. Savla, K., Bullo, F., and Frazzoli, E. [2007a] Traveling Salesperson ...2008] Traveling Salesperson Problems for the Dubins vehicle, IEEE Transactions on Automatic Control, 53(6), 1378–1391. Savla, K., Notarstefano, G., and

  10. An improved IEEE 802.11 protocol for reliable data transmission in power distribution fault diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Campoccia, F.; Di Silvestre, M.L.; Sanseverino, E.R.; Zizzo, G. [Palermo Univ., Palermo (Italy)

    2010-10-15

    In power systems, on-line transmission between local units and the central unit can be done by means of power line communications or wireless technology. During an electrical fault, the reliability of the distribution system depends on the security of the timely protective and restorative actions on the network. This paper focused on the WiFi system because of its economy and ease of installation. However, WiFi systems are typically managed by the IEEE 802.11 protocol, which is not reliable in terms of security in data communication. In WiFi networks, data is divided into packets and sent in succession to reduce errors within the radio channel. The IEEE 802.11 protocol has high probability for loss of packets or delay in their transmission. In order to ensure the reliability of data transmission times between two terminal units connected by WiFi stations, a new protocol was derived by modifying the IEEE 802.11. The improvements of the new protocol were highlighted and its capability for the diagnostic service was verified. The modified protocol eliminates the danger of collisions between packets and optimizes the transmission time for sending information. 6 refs., 7 tabs., 8 figs.

  11. On IEEE 802.15.6 IR-UWB receivers - simulations for DBPSK modulation.

    Science.gov (United States)

    Niemelä, Ville; Hämäläinen, Matti; Iinatti, Jari

    2013-01-01

    In 2002, Federal Communications Commission (FCC) was the first in defining regulations for ultra wideband (UWB) communications followed by Europe and Japan some years later. Focusing on impulse radio (IR) UWB, in 2007 was the time for the first published standard targeting in personal area networks, released by the IEEE. The second IEEE released standard including UWB definitions is targeted for wireless body area networks (WBAN) and was published in 2012. As the wireless communications has been and will be passing through almost any levels in society, the natural step with WBAN is using it in different medical, healthcare and wellbeing applications. The arguments for these are related to the modern lifestyle, in which people have increasingly more free time and are more interested in taking care of their health and wellbeing. Another challenge is the population composition, i.e., aging in developed countries which call for new solutions and procedures, particularly from cost wise. In this paper, we are evaluating UWB receivers based on the IEEE 802.15.6 physical layer definitions and capable of detecting differentially encoded modulation. The evaluation is performed using two different WBAN channel models.

  12. Analysis and Enhancement of IEEE 802.15.4e DSME Beacon Scheduling Model

    Directory of Open Access Journals (Sweden)

    Kwang-il Hwang

    2014-01-01

    Full Text Available In order to construct a successful Internet of things (IoT, reliable network construction and maintenance in a sensor domain should be supported. However, IEEE 802.15.4, which is the most representative wireless standard for IoT, still has problems in constructing a large-scale sensor network, such as beacon collision. To overcome some problems in IEEE 802.15.4, the 15.4e task group proposed various different modes of operation. Particularly, the IEEE 802.15.4e deterministic and synchronous multichannel extension (DSME mode presents a novel scheduling model to solve beacon collision problems. However, the DSME model specified in the 15.4e draft does not present a concrete design model but a conceptual abstract model. Therefore, in this paper we introduce a DSME beacon scheduling model and present a concrete design model. Furthermore, validity and performance of DSME are evaluated through experiments. Based on experiment results, we analyze the problems and limitations of DSME, present solutions step by step, and finally propose an enhanced DSME beacon scheduling model. Through additional experiments, we prove the performance superiority of enhanced DSME.

  13. The organisation of transactions : studying supply networkd using gaming simulation

    NARCIS (Netherlands)

    Meijer, S.A.

    2009-01-01

    This book studies the organisation of transactions in supply networks. More specifically it investigates the influence of social structure on the mode of organisation in supply networks. To gain new insights, the results in this book have been gathered using gaming simulation as a research method.

  14. Capacity Evaluation for IEEE 802.16e Mobile WiMAX

    Directory of Open Access Journals (Sweden)

    Chakchai So-In

    2010-01-01

    Full Text Available We present a simple analytical method for capacity evaluation of IEEE 802.16e Mobile WiMAX networks. Various overheads that impact the capacity are explained and methods to reduce these overheads are also presented. The advantage of a simple model is that the effect of each decision and sensitivity to various parameters can be seen easily. We illustrate the model by estimating the capacity for three sample applications—Mobile TV, VoIP, and data. The analysis process helps explain various features of IEEE 802.16e Mobile WiMAX. It is shown that proper use of overhead reducing mechanisms and proper scheduling can make an order of magnitude difference in performance. This capacity evaluation method can also be used for validation of simulation models.

  15. A Cross-Layer Key Management Scheme for MIPv6 Fast Handover over IEEE 802.11 Wireless LAN

    Directory of Open Access Journals (Sweden)

    Chang-Seop Park

    2015-01-01

    Full Text Available A new key management and security scheme is proposed to integrate Layer Two (L2 and Layer Three (L3 keys for secure and fast Mobile IPv6 handover over IEEE 802.11 Wireless Local Area Network (WLAN. Unlike the original IEEE 802.11-based Mobile IPv6 Fast Handover (FMIPv6 that requires time-consuming IEEE 802.1x-based Extensible Authentication Protocol (EAP authentication on each L3 handover, the newly proposed key management and security scheme requires only one 802.1x-EAP regardless of how many L3 handovers occur. Therefore, the proposed scheme reduces the handover latency that results from a lengthy 802.1x-based EAP. The proposed key management and security scheme is extensively analyzed in terms of security and performance, and the proposed security scheme is shown to be more secure than those that were previously proposed.

  16. Transaction based approach

    Science.gov (United States)

    Hunka, Frantisek; Matula, Jiri

    2017-07-01

    Transaction based approach is utilized in some methodologies in business process modeling. Essential parts of these transactions are human beings. The notion of agent or actor role is usually used for them. The paper on a particular example describes possibilities of Design Engineering Methodology for Organizations (DEMO) and Resource-Event-Agent (REA) methodology. Whereas the DEMO methodology can be regarded as a generic methodology having its foundation in the theory of Enterprise Ontology the REA methodology is regarded as the domain specific methodology and has its origin in accountancy systems. The results of these approaches is that the DEMO methodology captures everything that happens in the reality with a good empirical evidence whereas the REA methodology captures only changes connected with economic events. Economic events represent either change of the property rights to economic resource or consumption or production of economic resources. This results from the essence of economic events and their connection to economic resources.

  17. RELATED PARTY TRANSACTIONS - OVERVIEW

    OpenAIRE

    Alexandra Corlaciu; Adriana Tiron Tudor

    2011-01-01

    The purpose of the present investigation is to provide a short overview of themain implications arising from carrying related parties transactions: accounting reporting(related party disclosures - IAS 24), auditing (audit procedures for related partytransactions), taxation (issues regarding the transfer prices used for intra-grouptransactions). Although this research does not identify a problem with the scope to solve ithowever the utility might be observed by its contribution to the future d...

  18. Evaluating IEEE 802.15.4 for Cyber-Physical Systems

    Directory of Open Access Journals (Sweden)

    Vinel Alexey

    2011-01-01

    Full Text Available With rapid advancements in sensing, networking, and computing technologies, recent years have witnessed the emergence of cyber-physical systems (CPS in a broad range of application domains. CPS is a new class of engineered systems that features the integration of computation, communications, and control. In contrast to general-purpose computing systems, many cyber-physical applications are safety critical. These applications impose considerable requirements on quality of service (QoS of the employed networking infrastruture. Since IEEE 802.15.4 has been widely considered as a suitable protocol for CPS over wireless sensor and actuator networks, it is of vital importance to evaluate its performance extensively. Serving for this purpose, this paper will analyze the performance of IEEE 802.15.4 standard operating in different modes respectively. Extensive simulations have been conducted to examine how network QoS will be impacted by some critical parameters. The results are presented and analyzed, which provide some useful insights for network parameter configuration and optimization for CPS design.

  19. Estudi de l'ús del simulador OMNeT++ per a l'evaluació de xarxes IEEE 802.11n

    OpenAIRE

    Sans Prieto, Rubén

    2015-01-01

    OMNeT++ is a network simulator based on open source, the commercial version of this software is called OMNEST. It is one of the most popular network simulators in the academic and research community. This project aims at analyzing the behavior of OMNeT++ network simulator in IEEE 802.11n scenarios. This standard is partially implemented in the INET framework v3.0, dating back to July 2015. The present work consists of several chapters ranging from an explanation of the evolution of the IEEE 8...

  20. Memory Abstractions for Data Transactions

    OpenAIRE

    Herman, Nathaniel

    2015-01-01

    This thesis presents STO, a software transactional memory (STM) based not on low-level reads and writes on memory, but on datatypes—arrays, lists, queues, hash tables, and so forth—that explicitly support transactional operations. Conventional STMs allow programmers to write concurrent code in much the same way as sequential code—thereby more easily taking advantage of multiple CPU cores. However, these conventional STMs track every memory word accessed during a transaction, so even simple op...

  1. Utterance Generation for Transaction Dialogues

    OpenAIRE

    Hulstijn, J.; van Hessen, Adrianus J.

    1998-01-01

    This paper discusses the utterance generation module of a spoken dialogue system for transactions. Transactions are interesting because they involve obligations of both parties: the system should provide all relevant information; the user should feel committed to the transaction once it has been concluded. Utterance generation plays a major role in this. The utterance generation module works with prosodically annotated utterance templates. An appropriate template for a given dialogue act is s...

  2. Inventory Dynamics under Transaction Costs

    OpenAIRE

    Jean-Paul Chavas; Paula M. Despins; T. Randy Fortenbery

    2000-01-01

    A conceptual model of storage behavior is developed. Optimal intertemporal pricing is derived to analyze the effects of transaction costs on storage andarbitrage pricing. It is shown how transaction costs can rationalize the existence of an inverse carrying charge for inventory. The model is applied to U.S. soybeans stocks for the period 1960–95. The empirical results suggest that transaction costs have a significant influence on storage behavior andintertemporal arbitrage pricing. Copyright ...

  3. IEEE International Workshop on Machine Learning for Signal Processing: Preface

    DEFF Research Database (Denmark)

    Tao, Jianhua

    The 21st IEEE International Workshop on Machine Learning for Signal Processing will be held in Beijing, China, on September 18–21, 2011. The workshop series is the major annual technical event of the IEEE Signal Processing Society's Technical Committee on Machine Learning for Signal Processing....... This year the workshop is held in the National Laboratory of Pattern Recognition (NLPR), Institute of Automation, Chinese Academy of Sciences....

  4. Anonymous publication of sensitive transactional data

    KAUST Repository

    Ghinita, Gabriel

    2011-02-01

    Existing research on privacy-preserving data publishing focuses on relational data: in this context, the objective is to enforce privacy-preserving paradigms, such as k-anonymity and ℓ-diversity, while minimizing the information loss incurred in the anonymizing process (i.e., maximize data utility). Existing techniques work well for fixed-schema data, with low dimensionality. Nevertheless, certain applications require privacy-preserving publishing of transactional data (or basket data), which involve hundreds or even thousands of dimensions, rendering existing methods unusable. We propose two categories of novel anonymization methods for sparse high-dimensional data. The first category is based on approximate nearest-neighbor (NN) search in high-dimensional spaces, which is efficiently performed through locality-sensitive hashing (LSH). In the second category, we propose two data transformations that capture the correlation in the underlying data: 1) reduction to a band matrix and 2) Gray encoding-based sorting. These representations facilitate the formation of anonymized groups with low information loss, through an efficient linear-time heuristic. We show experimentally, using real-life data sets, that all our methods clearly outperform existing state of the art. Among the proposed techniques, NN-search yields superior data utility compared to the band matrix transformation, but incurs higher computational overhead. The data transformation based on Gray code sorting performs best in terms of both data utility and execution time. © 2006 IEEE.

  5. Synergistic Use of IEEE and IEC Nuclear Power Plant Standards

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, G

    2001-12-19

    Many organizations worldwide develop standards that affect nuclear instrumentation and control (I and C). Two of the primary standards organizations are the US IEEE's Nuclear Power Engineering Committee (NPEC), and the IEC subcommittee on Reactor Instrumentation (SC45A). This paper surveys the contents of the two sets of standards. Opportunities for complementary use of IEEE and IEC standards are discussed. The collections of IEEE. and IEC standards have some overlap, but in many cases cover significantly different topics. For example, IEEE standards go to great depth on environmental qualification of many specific types of components, while IEC covers the topic only at the general level. Conversely, certain IEC standards deal with specific instrumentation and control functions, a topic area where IEEE standards are largely mute. This paper considers how the two sets of standards may be used in a complementary fashion to achieve broader topic coverage than is possible using only one or the other standard suite. To understand the similarities and differences between IEC and IEEE nuclear standards layer diagrams were developed for each set of standards. Another paper [Johnson, 2001] used the same layer diagrams to investigate where coordination between the two sets of standards is most critical.

  6. Spectrum Hole Identification in IEEE 802.22 WRAN using Unsupervised Learning

    Directory of Open Access Journals (Sweden)

    V. Balaji

    2016-01-01

    Full Text Available In this paper we present a Cooperative Spectrum Sensing (CSS algorithm for Cognitive Radios (CR based on IEEE 802.22Wireless Regional Area Network (WRAN standard. The core objective is to improve cooperative sensing efficiency which specifies how fast a decision can be reached in each round of cooperation (iteration to sense an appropriate number of channels/bands (i.e. 86 channels of 7MHz bandwidth as per IEEE 802.22 within a time constraint (channel sensing time. To meet this objective, we have developed CSS algorithm using unsupervised K-means clustering classification approach. The received energy level of each Secondary User (SU is considered as the parameter for determining channel availability. The performance of proposed algorithm is quantified in terms of detection accuracy, training and classification delay time. Further, the detection accuracy of our proposed scheme meets the requirement of IEEE 802.22 WRAN with the target probability of falsealrm as 0.1. All the simulations are carried out using Matlab tool.

  7. Adaptive Backoff Algorithm for Contention Window for Dense IEEE 802.11 WLANs

    Directory of Open Access Journals (Sweden)

    Ikram Syed

    2016-01-01

    Full Text Available The performance improvement in IEEE 802.11 WLANs in widely fluctuating network loads is a challenging task. To improve the performance in this saturated state, we develop an adaptive backoff algorithm that maximizes the system throughput, reduces the collision probability, and maintains a high fairness for the IEEE 802.11 DCF under dense network conditions. In this paper, we present two main advantages of the proposed ABA-CW algorithm. First, it estimates the number of active stations and then calculates an optimal contention window based on the active station number. Each station calculates the channel state probabilities by observing the channel for the total backoff period. Based on these channel states probabilities, each station can estimate the number of active stations in the network, after which it calculates the optimal CW utilizing the estimated active number of stations. To evaluate the proposed mechanism, we derive an analytical model to determine the network performance. From our results, the proposed ABA-CW mechanism achieved better system performance compared to fixed-CW (BEB, EIED, LILD, and SETL and adaptive-CW (AMOCW, Idle Sense mechanisms. The simulation results confirmed the outstanding performance of the proposed mechanism in that it led to a lower collision probability, higher throughput, and high fairness.

  8. Fluid dynamics transactions

    CERN Document Server

    Fiszdon, W

    1965-01-01

    Fluid Dynamics Transactions, Volume 2 compiles 46 papers on fluid dynamics, a subdiscipline of fluid mechanics that deals with fluid flow. The topics discussed in this book include developments in interference theory for aeronautical applications; diffusion from sources in a turbulent boundary layer; unsteady motion of a finite wing span in a compressible medium; and wall pressure covariance and comparison with experiment. The certain classes of non-stationary axially symmetric flows in magneto-gas-dynamics; description of the phenomenon of secondary flows in curved channels by means of co

  9. Various New Statistical Models for Modeling and Change Detection in Multidimensional Dynamic Networks

    Science.gov (United States)

    2014-01-04

    Reproducing Kernel Hilbert Space (RKHS). IIE Transactions , accepted (Huang, S. is a former student of the PI, recently graduated and joined the faculty of University of South Florida). ...al. (2002) A Tutorial on Particle Filters for Online Nonlinear/non-Gaussian Bayesian Tracking." Signal Processing, IEEE Transactions on 50.2, 174

  10. NATO Education and Training Network

    Science.gov (United States)

    2012-02-01

    F-22 1.9.2.10 NETN Service Manager ..................................................................................................... F...Version Description Pitch Actors MSG-068 CGF Pitch Booster 1.2 Private Simulation Network Overlay Pitch NETN Service Manager MSG-068 Test tool for NETN...IEEE 1516-2010 1 Pitch NETN Service Manager Service Manager NETN Service Manager IEEE 1516-2010 1 Pitch Recorder Pitch Recorder Recorder IEEE 1516

  11. IEEE 1588 Time Synchronization Board in MTCA.4 Form Factor

    Science.gov (United States)

    Jabłoński, G.; Makowski, D.; Mielczarek, A.; Orlikowski, M.; Perek, P.; Napieralski, A.; Makijarvi, P.; Simrock, S.

    2015-06-01

    Distributed data acquisition and control systems in large-scale scientific experiments, like e.g. ITER, require time synchronization with nanosecond precision. A protocol commonly used for that purpose is the Precise Timing Protocol (PTP), also known as IEEE 1588 standard. It uses the standard Ethernet signalling and protocols and allows obtaining timing accuracy of the order of tens of nanoseconds. The MTCA.4 is gradually becoming the platform of choice for building such systems. Currently there is no commercially available implementation of the PTP receiver on that platform. In this paper, we present a module in the MTCA.4 form factor supporting this standard. The module may be used as a timing receiver providing reference clocks in an MTCA.4 chassis, generating a Pulse Per Second (PPS) signal and allowing generation of triggers and timestamping of events on 8 configurable backplane lines and two front panel connectors. The module is based on the Xilinx Spartan 6 FPGA and thermally stabilized Voltage Controlled Oscillator controlled by the digital-to-analog converter. The board supports standalone operation, without the support from the host operating system, as the entire control algorithm is run on a Microblaze CPU implemented in the FPGA. The software support for the card includes the low-level API in the form of Linux driver, user-mode library, high-level API: ITER Nominal Device Support and EPICS IOC. The device has been tested in the ITER timing distribution network (TCN) with three cascaded PTP-enabled Hirschmann switches and a GPS reference clock source. An RMS synchronization accuracy, measured by direct comparison of the PPS signals, better than 20 ns has been obtained.

  12. An Analysis Model of IEEE 802.11p with Difference Services

    Science.gov (United States)

    Tian, Jin; Xu, Lu

    2017-10-01

    Quality of Service (QoS) is a critical issue for the broadcast scheme of IEEE 802.11p systems in Vehicular Ad hoc Networks (VANETs). We present a 3-dimensional (3-D) Markov chain that the extra dimension, which models the deferring period, allows us to accurately solve for the broadcast scheme of 802.11p systems. The 3-D model solutions are validated by key simulations. Our analyses reveal that the lack of retransmission in the 802.11p system results in poor QoS performance during heavy traffic load, particularly for large VANETs.

  13. Latency and Jitter Analysis for IEEE 802.11e Wireless LANs

    Directory of Open Access Journals (Sweden)

    Sungkwan Youm

    2013-01-01

    Full Text Available This paper presents a numerical analysis of latency and jitter for IEEE 802.11e wireless local area networks (WLANs in a saturation condition, by using a Markov model. We use this model to explicate how the enhanced distributed coordination function (EDCF differentiates classes of service and to characterize the probability distribution of the medium access control (MAC layer packet latency and jitter, on which the quality of the voice over Internet protocol (VoIP calls is dependent. From the proposed analytic model, we can estimate the available number of nodes determining the system performance, in order to satisfy user demands on the latency and jitter.

  14. Distributed Fair Access Point Selection for Multi-Rate IEEE 802.11 WLANs

    Science.gov (United States)

    Gong, Huazhi; Nahm, Kitae; Kim, Jongwon

    In IEEE 802.11 networks, the access point (AP) selection based on the strongest signal strength often results in the extremely unfair bandwidth allocation among mobile users (MUs). In this paper, we propose a distributed AP selection algorithm to achieve a fair bandwidth allocation for MUs. The proposed algorithm gradually balances the AP loads based on max-min fairness for the available multiple bit rate choices in a distributed manner. We analyze the stability and overhead of the proposed algorithm, and show the improvement of the fairness via computer simulation.

  15. A Secure Simplification of the PKMv2 Protocol in IEEE 802.16e-2005

    DEFF Research Database (Denmark)

    Yuksel, Ender; Nielson, Hanne Riis; Nielsen, Christoffer Rosenkilde

    2007-01-01

    Static analysis is successfully used for automatically validating security properties of classical cryptographic protocols. In this paper, we shall employ the same technique to a modern security protocol for wireless networks, namely the latest version of the Privacy and Key Management protocol...... for IEEE 802.16e, PKMv2. This protocol seems to have an exaggerated mixture of security features. Thus, we iteratively investigate which components are necessary for upholding the security properties and which can be omitted safely. This approach is based on the LySa process calculus and employs...

  16. Building smart sensor nodes according to IEEE 1451.3 standard.

    Science.gov (United States)

    da Costa, Murilo N J; Neto, Olegario C S; Ferreira, José O; da Rocha, Adson F; de A Barbosa, Talles M G

    2011-01-01

    A Body Sensor Network (BSN) application requires many software and hardware adaptations to support correctly data exchanges between different sensor node architectures. However, these customizations demand extra time, cost and components. This paper introduces a simple development process in order to customize off-the-shelf BSN sensor nodes according to Transducer Bus Interface Modules (TBIM) standard. IEEE 1451.3 offers technical solutions for interfacing multiple and physically separated transducer allowing self-identification, self-configuration, plug and play and hot swapping capabilities. These are important requirements relating to most BSN applications.

  17. Transactional Sex among Noninjecting Illicit Drug Users: Implications for HIV Transmission

    Directory of Open Access Journals (Sweden)

    Rafael Alves Guimarães

    2016-01-01

    Full Text Available Noninjecting illicit drug users (NIDUs present high risk for HIV infection, due especially to transactional sex. This study aimed to estimate the prevalence and risk factors for transactional sex among NIDUs in the Southwest region of Goiás State, Central Brazil. The prevalence of self-reported transactional sex was 22.8%. Prevalence in women and men was 52.7% and 16.8%, respectively, a significant difference (p<0.001. Crack use and history of sexually transmitted infections (STI were risk factors for transactional sex in men. Homelessness, crack use, sex under the influence of drugs, and history of sexual violence were risk factors for transactional sex in women. A high prevalence of transactional sex was observed among NIDUs. This risk behavior may contribute to the high rates of HIV among this population and their social networks and in the general population.

  18. A Simulation Based Analysis of The Impact of IEEE 802.15.4 MAC Parameters on the Performance Under Different Traffic Loads

    Directory of Open Access Journals (Sweden)

    D. Rohm

    2009-01-01

    Full Text Available IEEE 802.15.4, a MAC/PHY protocol for low power and low data rate wireless networks, is emerging as the popular choice for various monitoring and control applications. Depending on the application, the traffic load on an IEEE 802.15.4 network may vary over a wide range. The performance of the protocol, measured in terms of the packet loss probability and the packet latency, depends upon the prevailing traffic load among the nodes competing for channel access, the level of interference from the hidden nodes and the configuration of IEEE 802.15.4 MAC parameters. In this paper, we analyze via simulations the impact of different configurable MAC parameters on the performance of beaconless IEEE 802.15.4 networks under different traffic loads and under different levels of interference from the hidden nodes. Based on this analysis, we suggest the values of IEEE 802.15.4 MAC parameters that results in a good tradeoff between the packet loss probability and the packet latency under different conditions.

  19. An Adaptive Medium Access Parameter Prediction Scheme for IEEE 802.11 Real-Time Applications

    Directory of Open Access Journals (Sweden)

    Estefanía Coronado

    2017-01-01

    Full Text Available Multimedia communications have experienced an unprecedented growth due mainly to the increase in the content quality and the emergence of smart devices. The demand for these contents is tending towards wireless technologies. However, these transmissions are quite sensitive to network delays. Therefore, ensuring an optimum QoS level becomes of great importance. The IEEE 802.11e amendment was released to address the lack of QoS capabilities in the original IEEE 802.11 standard. Accordingly, the Enhanced Distributed Channel Access (EDCA function was introduced, allowing it to differentiate traffic streams through a group of Medium Access Control (MAC parameters. Although EDCA recommends a default configuration for these parameters, it has been proved that it is not optimum in many scenarios. In this work a dynamic prediction scheme for these parameters is presented. This approach ensures an appropriate traffic differentiation while maintaining compatibility with the stations without QoS support. As the APs are the only devices that use this algorithm, no changes are required to current network cards. The results show improvements in both voice and video transmissions, as well as in the QoS level of the network that the proposal achieves with regard to EDCA.

  20. FINANCING OF INTERNATIONAL TRANSACTIONS

    Directory of Open Access Journals (Sweden)

    RADU NICOLAE BĂLUNĂ

    2013-02-01

    Full Text Available Financing (funding is essentially the purchase of funds necessary for a business. This can be done from internal sources (company’s own funds or external (borrowed funds. The high value of goods traded in international trade makes revenues generated from internal resources not sufficient to settle the value of the goods. Thus, it is frequent to resort to borrowed funds. In International Business Transactions, external financing is done both by classical techniques of credit (credit supplier and buyer credit and modern techniques of financing (factoring, forfeiting, leasing all trade tailored. In terms of the length of financing, accounting funding is short-term (1-12 months and long-term financing (over a year. In principle, export and import operations prevailing short-term financing techniques, while international investment and industrial cooperation actions are specific long-term funding

  1. Implicit Block ACK Scheme for IEEE 802.11 WLANs

    Science.gov (United States)

    Sthapit, Pranesh; Pyun, Jae-Young

    2016-01-01

    The throughput of IEEE 802.11 standard is significantly bounded by the associated Medium Access Control (MAC) overhead. Because of the overhead, an upper limit exists for throughput, which is bounded, including situations where data rates are extremely high. Therefore, an overhead reduction is necessary to achieve higher throughput. The IEEE 802.11e amendment introduced the block ACK mechanism, to reduce the number of control messages in MAC. Although the block ACK scheme greatly reduces overhead, further improvements are possible. In this letter, we propose an implicit block ACK method that further reduces the overhead associated with IEEE 802.11e’s block ACK scheme. The mathematical analysis results are presented for both the original protocol and the proposed scheme. A performance improvement of greater than 10% was achieved with the proposed implementation.

  2. DoS detection in IEEE 802.11 with the presence of hidden nodes.

    Science.gov (United States)

    Soryal, Joseph; Liu, Xijie; Saadawi, Tarek

    2014-07-01

    The paper presents a novel technique to detect Denial of Service (DoS) attacks applied by misbehaving nodes in wireless networks with the presence of hidden nodes employing the widely used IEEE 802.11 Distributed Coordination Function (DCF) protocols described in the IEEE standard [1]. Attacker nodes alter the IEEE 802.11 DCF firmware to illicitly capture the channel via elevating the probability of the average number of packets transmitted successfully using up the bandwidth share of the innocent nodes that follow the protocol standards. We obtained the theoretical network throughput by solving two-dimensional Markov Chain model as described by Bianchi [2], and Liu and Saadawi [3] to determine the channel capacity. We validated the results obtained via the theoretical computations with the results obtained by OPNET simulator [4] to define the baseline for the average attainable throughput in the channel under standard conditions where all nodes follow the standards. The main goal of the DoS attacker is to prevent the innocent nodes from accessing the channel and by capturing the channel's bandwidth. In addition, the attacker strives to appear as an innocent node that follows the standards. The protocol resides in every node to enable each node to police other nodes in its immediate wireless coverage area. All innocent nodes are able to detect and identify the DoS attacker in its wireless coverage area. We applied the protocol to two Physical Layer technologies: Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS) and the results are presented to validate the algorithm.

  3. Implementation of Networking-by-Touch to Small Unit, Network-Enabled Operations

    Science.gov (United States)

    2010-09-01

    Computing and Communications (PerCom’03) downloaded on Mar. 3, 2010 from IEEE Xplore . [28] K. Kangas and J. Roning, “Using code mobility to create...Tactical Edge Networks,” Defense Advanced Projects Agency (DARPA). Downloaded on May 14, 2010. from IEEE Xplore . [33] V. Cerf. “Interplanetary Internet...health, Networking, Applications and Services, 7-9 July 2008. Downloaded on May 31, 2010. from IEEE Xplore . [43] D. Haskin, “The thirteen mobile

  4. IEEE prize awarded to CERN PhD student

    CERN Multimedia

    2006-01-01

    Rafael Ballabriga Suñe is the recipient of the 2006 Institute of Electrical and Electronics Engineers, Inc. (IEEE) Nuclear and Plasma Sciences Society (NPSS)'s Student Paper Award. Ballabriga's winning paper reported on a prototype chip, which belongs to a new generation of single photon counting hybrid pixel detector readout chips - Medipix3. The award was presented by the deputy programme chair Vince Cianciolo (left) at the IEEE Nuclear Science Symposium held in San Diego on 29 October to 4 November.

  5. Performance analysis of IEEE 802.11g TCM waveforms transmitted over a channel with pulse-noise interference

    OpenAIRE

    Drivas, Athanasios

    2007-01-01

    Trellis-coded modulation (TCM) is a technique that introduces forward error correction (FEC) coding without increasing the bandwidth of the channel signal. TCM combines binary convolution codes with M-ary signal constellation. The application of TCM combines FEC coding and M-ary modulation in one operation. The objective of this thesis is to investigate the performance of an orthogonal frequency-division multiplexing (OFDM) based IEEE 802.11g wireless local area network (WLAN) standard receiv...

  6. Error detecting capabilities of the shortened Hamming codes adopted for error detection in IEEE Standard 802.3

    Science.gov (United States)

    Fujiwara, Toru; Kasami, Tadao; Lin, Shu

    1989-01-01

    The error-detecting capabilities of the shortened Hamming codes adopted for error detection in IEEE Standard 802.3 are investigated. These codes are also used for error detection in the data link layer of the Ethernet, a local area network. The weight distributions for various code lengths are calculated to obtain the probability of undetectable error and that of detectable error for a binary symmetric channel with bit-error rate between 0.00001 and 1/2.

  7. A Novel Design of IEEE 802.15.4 and Solar Based Autonomous Water Quality Monitoring Prototype using ECHERP

    OpenAIRE

    Fredrick Romanus Ishengoma

    2014-01-01

    The recently advancement in Wireless Sensor Network (WSN) technology has brought new distributed sensing applications such as water quality monitoring. With sensing capabilities and using parameters like pH, conductivity and temperature, the quality of water can be known. This paper proposes a novel design based on IEEE 802.15.4 (Zig-Bee protocol) and solar energy called Autonomous Water Quality Monitoring Prototype (AWQMP). The prototype is designed to use ECHERP routing protocol and Adruino...

  8. 28 CFR 80.3 - Transaction.

    Science.gov (United States)

    2010-07-01

    ... made prior to the requestor's commitment to proceed with a transaction. ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Transaction. 80.3 Section 80.3 Judicial... Transaction. The entire transaction which is the subject of the request must be an actual—not a hypothetical...

  9. International Symposium on Ubiquitous Networking

    CERN Document Server

    Medromi, Hicham; Sadik, Mohamed

    2016-01-01

    This volume publishes new trends and findings in hot topics related to ubiquitous computing/networking. It is the outcome of UNet - ainternational scientific event that took place on September 08-10, 2015, in the fascinating city of Casablanca, Morocco. UNet’15 is technically sponsored by IEEE Morocco Section and IEEE COMSOC Morocco Chapter.

  10. Principles of Transactional Memory The Theory

    CERN Document Server

    Guerraoui, Rachid

    2010-01-01

    Transactional memory (TM) is an appealing paradigm for concurrent programming on shared memory architectures. With a TM, threads of an application communicate, and synchronize their actions, via in-memory transactions. Each transaction can perform any number of operations on shared data, and then either commit or abort. When the transaction commits, the effects of all its operations become immediately visible to other transactions; when it aborts, however, those effects are entirely discarded. Transactions are atomic: programmers get the illusion that every transaction executes all its operati

  11. Investigating the efficiency of IEEE 802.15.4 for medical monitoring applications.

    Science.gov (United States)

    Pelegris, P; Banitsas, K

    2011-01-01

    Recent advancements in wireless communications technologies bring us one step closer to provide reliable Telecare services as an alternative to patients staying in a hospital mainly for monitoring purposes. In this research we investigate the efficiency of IEEE 802.15.4 in a simple scenario where a patient is being monitored using an ECG and a blood analysis module. This approach binds well with assisted living solutions, by sharing the network infrastructure for both monitoring and control while taking advantage of the low power features of the protocol. Such applications are becoming more and more realistic to implement as IEEE 802.15.4 compatible hardware becomes increasingly available. Our aim is to examine the impact of Beacon and Superframe Order in the medium access delay, dropped packets, end to end delay, average retransmission attempts and consumed power focusing on this bandwidth demanding situation where the network load does not allow low duty cycles, in order to draw some conclusions on the effect that this will have to telemonitoring applications.

  12. Micro-transactions for concurrent data structures

    DEFF Research Database (Denmark)

    Meawad, Fadi; Iyer, Karthik; Schoeberl, Martin

    2013-01-01

    implementation of transactional memory that we call micro-transactions. In particular, we argue that hardware support for micro-transactions allows us to efficiently implement certain data structures. Those data structures are difficult to realize with the atomic operations provided by stock hardware and provide......, atomic instructions, and micro-transactions. Our results suggest that transactional memory is an interesting alternative to traditional concurrency control mechanisms....

  13. Guía para citar y referenciar. Estilo IEEE

    OpenAIRE

    Ruiz de Luzuriaga Peña, Manuel

    2016-01-01

    Esta guía ha sido redactada para uso de los alumnos de la Universidad Pública de Navarra en la redacción de sus trabajos académicos, siguiendo las pautas de IEEE Edition Style Guide y, para algunos aspectos no contemplados en esa obra, de la Guía para citar y referenciar APA Style.

  14. Eleanor McElwee and the Formation of IEEE PCS

    Science.gov (United States)

    Malone, Edward A.

    2015-01-01

    This article examines the historical professional project that created the Institute of Radio Engineers' Professional Group on Engineering Writing an Speech (IRE PGEWS)--now called the Institute of Electrical and Electronics Engineers' Professional Communication Society (IEEE PCS)--and recounts the group's early history in detail. It also traces…

  15. Specialty and Systems Engineering Supplement to IEEE 15288.1

    Science.gov (United States)

    2017-08-28

    SYSTEMS CENTER TAILORING SPECIALTY AND SYSTEMS ENGINEERING SUPPLEMENT TO IEEE-15288.1 APPROVED FOR PUBLIC...document) also published as SMC-T-006 (2017) (1) Changed title from “Specialty Engineering Supplement…” to “Specialty and Systems Engineering ... systems engineering tailoring (2) Provides document history (3) Documented current status of documents and added reference to adoption notices.

  16. Managing business networks and buyer-supplier relationships. How information obtained from the business network affects trust, transaction specific investments, collaboration and performance in the Dutch Potted Plant and Flower Industry

    NARCIS (Netherlands)

    Claro, D.P.

    2004-01-01

    Managing networks and buyer-supplier relationships " attempt to provide scientific sound discussion for problems faced in business linkages. Business networks, supply chains and buyer-supplier relationships all refer to business linkages, from a web of connected relationships to a dyadic

  17. Development of a low mobility IEEE 802.15.4 compliant VANET system for urban environments.

    Science.gov (United States)

    Nazabal, Juan Antonio; Falcone, Francisco; Fernández-Valdivielso, Carlos; Matías, Ignacio Raúl

    2013-05-29

    The use of Vehicular Ad-Hoc Networks (VANETs) is growing nowadays and it includes both roadside-to-vehicle communication (RVC) and inter-vehicle communication (IVC). The purpose of VANETs is to exchange useful information between vehicles and the roadside infrastructures for making an intelligent use of them. There are several possible applications for this technology like: emergency warning system for vehicles, cooperative adaptive cruise control or collision avoidance, among others. The objective of this work is to develop a VANET prototype system for urban environments using IEEE 802.15.4 compliant devices. Simulation-based values of the estimated signal strength and radio link quality values are obtained and compared with measurements in outdoor conditions to validate an implemented VANET system. The results confirm the possibility of implementing low cost vehicular communication networks operating at moderate vehicular speeds.

  18. Development of a Low Mobility IEEE 802.15.4 Compliant VANET System for Urban Environments

    Directory of Open Access Journals (Sweden)

    Ignacio Raúl Matías

    2013-05-01

    Full Text Available The use of Vehicular Ad-Hoc Networks (VANETs is growing nowadays and it includes both roadside-to-vehicle communication (RVC and inter-vehicle communication (IVC. The purpose of VANETs is to exchange useful information between vehicles and the roadside infrastructures for making an intelligent use of them. There are several possible applications for this technology like: emergency warning system for vehicles, cooperative adaptive cruise control or collision avoidance, among others. The objective of this work is to develop a VANET prototype system for urban environments using IEEE 802.15.4 compliant devices. Simulation-based values of the estimated signal strength and radio link quality values are obtained and compared with measurements in outdoor conditions to validate an implemented VANET system. The results confirm the possibility of implementing low cost vehicular communication networks operating at moderate vehicular speeds.

  19. Service Differentiated and Adaptive CSMA/CA over IEEE 802.15.4 for Cyber-Physical Systems

    Directory of Open Access Journals (Sweden)

    Feng Xia

    2013-01-01

    Full Text Available Cyber-Physical Systems (CPS that collect, exchange, manage information, and coordinate actions are an integral part of the Smart Grid. In addition, Quality of Service (QoS provisioning in CPS, especially in the wireless sensor/actuator networks, plays an essential role in Smart Grid applications. IEEE 802.15.4, which is one of the most widely used communication protocols in this area, still needs to be improved to meet multiple QoS requirements. This is because IEEE 802.15.4 slotted Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA employs static parameter configuration without supporting differentiated services and network self-adaptivity. To address this issue, this paper proposes a priority-based Service Differentiated and Adaptive CSMA/CA (SDA-CSMA/CA algorithm to provide differentiated QoS for various Smart Grid applications as well as dynamically initialize backoff exponent according to traffic conditions. Simulation results demonstrate that the proposed SDA-CSMA/CA scheme significantly outperforms the IEEE 802.15.4 slotted CSMA/CA in terms of effective data rate, packet loss rate, and average delay.

  20. Service differentiated and adaptive CSMA/CA over IEEE 802.15.4 for Cyber-Physical Systems.

    Science.gov (United States)

    Xia, Feng; Li, Jie; Hao, Ruonan; Kong, Xiangjie; Gao, Ruixia

    2013-01-01

    Cyber-Physical Systems (CPS) that collect, exchange, manage information, and coordinate actions are an integral part of the Smart Grid. In addition, Quality of Service (QoS) provisioning in CPS, especially in the wireless sensor/actuator networks, plays an essential role in Smart Grid applications. IEEE 802.15.4, which is one of the most widely used communication protocols in this area, still needs to be improved to meet multiple QoS requirements. This is because IEEE 802.15.4 slotted Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) employs static parameter configuration without supporting differentiated services and network self-adaptivity. To address this issue, this paper proposes a priority-based Service Differentiated and Adaptive CSMA/CA (SDA-CSMA/CA) algorithm to provide differentiated QoS for various Smart Grid applications as well as dynamically initialize backoff exponent according to traffic conditions. Simulation results demonstrate that the proposed SDA-CSMA/CA scheme significantly outperforms the IEEE 802.15.4 slotted CSMA/CA in terms of effective data rate, packet loss rate, and average delay.

  1. Evaluation of IEEE 802.11g and 802.16 for Lunar Surface Exploration Missions Using MACHETE Simulations

    Science.gov (United States)

    Segui, John; Jennings, Esther; Vyas, Hemali

    2009-01-01

    In this paper, we investigated the suitability of terrestrial wireless networking technologies for lunar surface exploration missions. Specifically, the scenario we considered consisted of two teams of collaborating astronauts, one base station and one rover, where the base station and the rover have the capability of acting as relays. We focused on the evaluation of IEEE 802.11g and IEEE 802.16 protocols, simulating homogeneous 802.11g network, homogeneous 802.16 network, and heterogeneous network using both 802.11g and 802.16. A mix of traffic flows were simulated, including telemetry, caution and warning, voice, command and file transfer. Each traffic type had its own distribution profile, data volume, and priority. We analyzed the loss and delay trade-offs of these wireless protocols with various link-layer options. We observed that 802.16 network managed the channel better than an 802.11g network due to controlled infrastructure and centralized scheduling. However, due to the centralized scheduling, 802.16 also had a longer delay. The heterogeneous (hybrid) of 802.11/802.16 achieved a better balance of performance in terms of data loss and delay compared to using 802.11 or 802.16 alone.

  2. Predictable and reliable ECG monitoring over IEEE 802.11 WLANs within a hospital.

    Science.gov (United States)

    Park, Juyoung; Kang, Kyungtae

    2014-09-01

    Telecardiology provides mobility for patients who require constant electrocardiogram (ECG) monitoring. However, its safety is dependent on the predictability and robustness of data delivery, which must overcome errors in the wireless channel through which the ECG data are transmitted. We report here a framework that can be used to gauge the applicability of IEEE 802.11 wireless local area network (WLAN) technology to ECG monitoring systems in terms of delay constraints and transmission reliability. For this purpose, a medical-grade WLAN architecture achieved predictable delay through the combination of a medium access control mechanism based on the point coordination function provided by IEEE 802.11 and an error control scheme based on Reed-Solomon coding and block interleaving. The size of the jitter buffer needed was determined by this architecture to avoid service dropout caused by buffer underrun, through analysis of variations in transmission delay. Finally, we assessed this architecture in terms of service latency and reliability by modeling the transmission of uncompressed two-lead electrocardiogram data from the MIT-BIH Arrhythmia Database and highlight the applicability of this wireless technology to telecardiology.

  3. Improving Energy Efficiency in Idle Listening of IEEE 802.11 WLANs

    Directory of Open Access Journals (Sweden)

    Muhammad Adnan

    2016-01-01

    Full Text Available This paper aims to improve energy efficiency of IEEE 802.11 wireless local area networks (WLANs by effectively dealing with idle listening (IL, which is required for channel sensing and is unavoidable in a contention-based channel access mechanism. Firstly, we show that IL is a dominant source of energy drain in WLANs and it cannot be effectively alleviated by the power saving mechanism proposed in the IEEE 802.11 standard. To solve this problem, we propose an energy-efficient mechanism that combines three schemes in a systematic way: downclocking, frame aggregation, and contention window adjustment. The downclocking scheme lets a station remain in a semisleep state when overhearing frames destined to neighbor stations, whereby the station consumes the minimal energy without impairing channel access capability. As well as decreasing the channel access overhead, the frame aggregation scheme prolongs the period of semisleep time. Moreover, by controlling the size of contention window based on the number of stations, the proposed mechanism decreases unnecessary IL time due to collision and retransmission. By deriving an analysis model and performing extensive simulations, we confirm that the proposed mechanism significantly improves the energy efficiency and throughput, by up to 2.8 and 1.8 times, respectively, compared to the conventional power saving mechanisms.

  4. A Joint Beamforming based SDMA Protocol for IEEE 802.11n Downlink

    Directory of Open Access Journals (Sweden)

    Cheng Guo

    2015-09-01

    Full Text Available To support space division multiple access (SDMA in the IEEE 802.11n downlink, a joint beamforming based MAC protocol, J-MAC is presented in this paper. An access point (AP follows J-MAC, which employs multiple array antennas, and user equipments (UEs follow the IEEE 802.11x standard which employ omni-directional MIMO antennas. J-MAC maintains full compatibility with 802.11x, and UEs do not change any more. In J-MAC, firstly, the AP achieves the weight vector for the array antenna-based beamforming, and updates it periodically. Secondly, before transmitting any data-frame, the AP achieves the weight vector for the MIMO-based beamforming, which should be updated in each transmission. Finally, after getting the joint beamforming, the AP transmits its data-frames to multiple UEs simultaneously. Simulation results show that J-MAC can support the joint beamforming effectively and provide much higher network throughput, lower delay, jitter and packet-loss-rate than DCF does.

  5. Transaction Cost and Activity of Economic Agents

    Directory of Open Access Journals (Sweden)

    Ivan D. Kotliarov

    2017-03-01

    Full Text Available The goal of the present paper is to clarify the role of transaction cost for existence of an economic agent. It is demonstrated that the opposition of transaction cost and transformation cost is not rigid and there are costs that contain both transaction and transformation component. In addition the amount of transaction cost depends on parameters of company’s activity. This is why it is hardly possible to find the precise minimum of transaction cost and the model of organization of transactions within firm will be flexible. The firm’s structure contains special transaction divisions (centers of transaction cost that are necessary for existence of the firm as a mechanism of organization of transactions (opposed to market. The status of these divisions depends on firm’s size. Transaction divisions can also exist outside the firm. They will minimize transaction costs of other economic agents on the basis of external effect of scale. External transaction divisions can exist both as collective structures (coordinating centers of strategic alliances as well as independent ones (franchisors. A comparative analysis of transaction divisions and centers of cost was done. It was demonstrated that these elements of the firm have different economic and organizational structure. The notion of cost of external profitability was introduced. This notion can be used to analyze reasons for merger of companies or for their existence as independent structures. It is demonstrated that one of the functions of the firm is to use resources that cannot be used within independent production units.

  6. HTML thin client and transactions

    CERN Document Server

    Touchette, J F

    1999-01-01

    When writing applications for thin clients such as Web browsers, you face several challenges that do not exist with fat-client applications written in Visual Basic, Delphi, or Java. For one thing, your development tools do not include facilities for automatically building reliable, nonrepeatable transactions into applications. Consequently, you must devise your own techniques to prevent users from transmitting duplicate transactions. The author explains how to implement reliable, nonrepeatable transactions using a technique that is applicable to any Java Server Development Kit based architecture. Although the examples presented are based on the IBM WebSphere 2.1 Application Server, they do not make use of any IBM WebSphere extensions. In short, the concepts presented here can be implemented in Perl CGI and ASP scripts, and the sample code has been tested with JDK 1.1.6 and 1.2. (0 refs).

  7. IEEE prize awarded to CERN PhD student

    CERN Multimedia

    2006-01-01

    Rafael Ballabriga Suñe (right) receives the Student Paper Award. Rafael Ballabriga Suñe is the recipient of the 2006 Institute of Electrical and Electronics Engineers, Inc. (IEEE) Nuclear and Plasma Sciences Society (NPSS)'s Student Paper Award. Ballabriga's winning paper reported on a prototype chip, which belongs to a new generation of single photon counting hybrid pixel detector readout chips - Medipix3. The NPSS established this award in 2005 to encourage outstanding student contributions and greater student participation as principle or sole authors of papers. The prizes were presented at the IEEE Nuclear Science Symposium held in San Diego on 29 October to 4 November. The prototype chip was designed by Ballabriga based on ideas generated within the CERN Medipix team - part of the PH Microelectronics group. It could be used in various fields in the future, including medical imaging, neutron imaging, electron microscopy, radiation monitoring and other applications in high-energy physics. The novel aspe...

  8. 17th IEEE NPSS Real Time Conference – RT-2010

    CERN Multimedia

    Carlos Varandas

    2010-01-01

    Congress Centre of “Instituto Superior Técnico”, Lisboa, Portugal, 24-28 May, 2010 ABSTRACT SUBMISSION OPEN Abstract Submission Deadline: March 1st, 2010 Dear Sir/Madam, We are pleased to announce that abstract submission for the 17th IEEE NPSS Real Time Conference is now open on our web site. The deadline for submitting an abstract is 1st March 2010. Full conference details General Chairman

  9. Decision, Transaction, Law and Contract

    DEFF Research Database (Denmark)

    Koch, Carsten Allan

    is transaction cost economics in the tradition of Oliver E. Williamson. The foundation for this tradition was laid by 1991 Nobel Laureate Ronald Coase in a paper, “The Nature of the Firm” in 1937. But the breakthrough as an influential research program was achieved with Williamson’s influential “Markets...... and Hierarchies” from 1975. Since then Williamson has, almost singlehandedly, erected an impressive research program which aims at explaining the institutional structures at the micro-level under which economic transactions take place. A number of different phenomena that were very hard to rationalize given...

  10. A Mechanically Proved and an Incremental Development of the Session Initiation Protocol INVITE Transaction

    Directory of Open Access Journals (Sweden)

    Rajaa Filali

    2014-01-01

    Full Text Available The Session Initiation Protocol (SIP is an application layer signaling protocol used to create, manage, and terminate sessions in an IP based network. SIP is considered as a transactional protocol. There are two main SIP transactions, the INVITE transaction and the non-INVITE transaction. The SIP INVITE transaction specification is described in an informal way in Request for Comments (RFC 3261 and modified in RFC 6026. In this paper we focus on the INVITE transaction of SIP, over reliable and unreliable transport mediums, which is used to initiate a session. In order to ensure the correctness of SIP, the INVITE transaction is modeled and verified using event-B method and its Rodin platform. The Event-B refinement concept allows an incremental development by defining the studied system at different levels of abstraction, and Rodin discharges almost all proof obligations at each level. This interaction between modeling and proving reduces the complexity and helps in assuring that the INVITE transaction SIP specification is correct, unambiguous, and easy to understand.

  11. Transactions in domain-specific information systems

    Science.gov (United States)

    Zacek, Jaroslav

    2017-07-01

    Substantial number of the current information system (IS) implementations is based on transaction approach. In addition, most of the implementations are domain-specific (e.g. accounting IS, resource planning IS). Therefore, we have to have a generic transaction model to build and verify domain-specific IS. The paper proposes a new transaction model for domain-specific ontologies. This model is based on value oriented business process modelling technique. The transaction model is formalized by the Petri Net theory. First part of the paper presents common business processes and analyses related to business process modeling. Second part defines the transactional model delimited by REA enterprise ontology paradigm and introduces states of the generic transaction model. The generic model proposal is defined and visualized by the Petri Net modelling tool. Third part shows application of the generic transaction model. Last part of the paper concludes results and discusses a practical usability of the generic transaction model.

  12. Transactions Concurrency Control in Web Service Environment

    DEFF Research Database (Denmark)

    Alrifai, Mohammad; Dolog, Peter; Nejdl, Wolfgang

    2006-01-01

    an engineering point of view as it does not change the way consumers or clients of web services have to be programmed. Furthermore, it avoids direct communication between transaction coordinators which preserves security by keeping the information about business transactions restricted to the coordinators which......Business transactions in web service environments run with relaxed isolation and atomicity property. In such environments, transactions can commit and roll back independently on each other. Transaction management has to reflect this issue and address the problems which result for example from...... concurrent access to web service resources and data. In this paper we propose an extension to the WS-Transaction Protocol which ensures the consistency of the data when independent business transactions access the data concurrently under the relaxed transaction properties. Our extension is based...

  13. Rethinking Ethiopian Secured Transactions Law through ...

    African Journals Online (AJOL)

    Various countries have reformed their secured transaction laws recognizing the significance of modern secured transactions law in enhancing access to credit and economic development. Ethiopia has not undertaken comprehensive secured transactions law reform, despite the demonstrable mismatch between the legal ...

  14. 5 CFR 1640.4 - Account transactions.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Account transactions. 1640.4 Section 1640... STATEMENTS § 1640.4 Account transactions. (a) Where relevant, the following transactions will be reported in each individual account statement: (1) Contributions; (2) Withdrawals; (3) Forfeitures; (4) Loan...

  15. Managing for Success: The Role of Transactional and Relational Mechanisms in Buyer-Supplier Relationships

    Directory of Open Access Journals (Sweden)

    Khuram Shahzad

    2015-03-01

    Full Text Available Firms are collaborating more in supply chain network and identified the importance of business relationships. This idea was embraced by academic and empirical research in operations management since last decade. Therefore, the purpose of this study is to develop a comprehensive integrated conceptual and empirical framework which elaborates the role of transactional and relational factors to highlight buyer-supplier relationship performance. While, limited studies explored these factors separately neither provide the dynamic interactive role of transactional and relational factors in an integrated framework. Through multiple case studies, findings reveal that impact of relational factors of trust and communication has constructive influence in reducing the transaction cost and improving relationship performance. This study contributes to debate on managing complex business network relationships by providing a combined theoretical setting (transaction cost economics and social exchange theory and empirically proven integrated model. Managers can enhance the operational performance by selecting the most suitable constructs.

  16. Personality-relationship transactions revisited.

    Science.gov (United States)

    Neyer, Franz J; Mund, Marcus; Zimmermann, Julia; Wrzus, Cornelia

    2014-12-01

    The transactional paradigm states that people create, maintain, and change their environments according to their personalities. At the same time, the environment reacts back on personality. As social relationships are part of an individual's environment, this likewise implies that there are reciprocal transactions between personality and relationships. However, earlier studies have concluded that adult personality traits are so stable that they have a stronger effect on later relationships, but that relationship effects on personality are negligible. In this article, we contend that personality-relationship transactions should be revisited. We submit that the relative powers of personality versus relationship effects depend on the type of life transition during which the effects take place: Relationship effects on personality development are more likely to emerge in the context of rather normative and highly scripted life transitions, whereas personality effects on relationship development are more likely to occur in the context of rather non-normative life transitions that are less regulated by social expectations. We illustrate these assumptions with examples from our own work and other findings reported in the literature. Furthermore, we theorize that effects of personality-relationship transactions on health also vary with the normativeness of the eliciting life transition. © 2013 Wiley Periodicals, Inc.

  17. Transformational and transactional leadership conceptualization ...

    African Journals Online (AJOL)

    The study to revalidated and re-examined the factor structure and the conceptualization of the transformational and transactional leadership for a possible application to the study of leadership in Nigerian applied settings. Data were collected from 212 employees (160 males and 52 females) who rated eight CEOs (4 males ...

  18. PayPal Transactions Security

    OpenAIRE

    Razvan Toader

    2014-01-01

    Recent threads to prominent organizations and companies have greatly increased the need for information security. Many measures have been designed and developed to guard against threats from outsider attacks. Technologies are actively implemented to prohibit such attacks that could actively prohibit rogue connections. In this paper, common vulnerabilities for PayPal transactions identified as well as solutions for defending against them.

  19. Transactions on Computational Science IX

    DEFF Research Database (Denmark)

    The 9th issue of the Transactions on Computational Science journal, edited by François Anton, is devoted to the subject of Voronoi diagrams in science and engineering. The 9 papers included in the issue constitute extended versions of selected papers from the International Symposium on Voronoi...

  20. The Transaction Footprints of Scottish Food And Drink SMEs

    Directory of Open Access Journals (Sweden)

    Copus Andrew

    2016-09-01

    Full Text Available This paper presents a survey approach to measuring the “transaction footprints” of rural small and medium sized enterprises (SMEs. Combined with a graphical presentation of results, this contributes to the evidence base on the roles of local and global linkages. Findings suggest that the food and drink industry of Scotland is relatively localised in its input and sales interaction pattern, although substantial variations, associated with product specialisms, remoteness/accessibility, input purchasing and marketing strategies, exist. Localised SMEs have weathered the recession slightly better, but more outward-looking in firms tend to have greater optimism about the future. Transaction footprint analysis should be viewed as component of an ongoing process of re-mapping the network infrastructure of the rural economy, alongside analysis of untraded interdependencies, and institutional networks in the realm of governance.

  1. Beamforming transmission in IEEE 802.11ac under time-varying channels.

    Science.gov (United States)

    Yu, Heejung; Kim, Taejoon

    2014-01-01

    The IEEE 802.11ac wireless local area network (WLAN) standard has adopted beamforming (BF) schemes to improve spectral efficiency and throughput with multiple antennas. To design the transmit beam, a channel sounding process to feedback channel state information (CSI) is required. Due to sounding overhead, throughput increases with the amount of transmit data under static channels. Under practical channel conditions with mobility, however, the mismatch between the transmit beam and the channel at transmission time causes performance loss when transmission duration after channel sounding is too long. When the fading rate, payload size, and operating signal-to-noise ratio are given, the optimal transmission duration (i.e., packet length) can be determined to maximize throughput. The relationship between packet length and throughput is also investigated for single-user and multiuser BF modes.

  2. Performance Analysis of IEEE 802.15.6 CSMA/CA Protocol for WBAN Medical Scenario through DTMC Model.

    Science.gov (United States)

    Kumar, Vivek; Gupta, Bharat

    2016-12-01

    The newly drafted IEEE 802.15.6 standard for Wireless Body Area Networks (WBAN) has been concentrating on a numerous medical and non-medical applications. Such short range wireless communication standard offers ultra-low power consumption with variable data rates from few Kbps to Mbps in, on or around the proximity of the human body. In this paper, the performance analysis of carrier sense multiple access with collision avoidance (CSMA/CA) scheme based on IEEE 802.15.6 standard in terms of throughput, reliability, clear channel assessment (CCA) failure probability, packet drop probability, and end-to-end delay has been presented. We have developed a discrete-time Markov chain (DTMC) to significantly evaluate the performances of IEEE 802.15.6 CSMA/CA under non-ideal channel condition having saturated traffic condition including node wait time and service time. We also visualize that, as soon as the payload length increases the CCA failure probability increases, which results in lower node's reliability. Also, we have calculated the end-to-end delay in order to prioritize the node wait time cause by backoff and retransmission. The user priority (UP) wise DTMC analysis has been performed to show the importance of the standard especially for medical scenario.

  3. Priority-Based Inter-Vehicle Communication for Highway Safety Messaging Using IEEE 802.11e

    Directory of Open Access Journals (Sweden)

    Chakkaphong Suthaputchakun

    2009-01-01

    Full Text Available We propose to use IEEE 802.11e in conjunction with retransmission mechanisms for priority-based Intervehicle Communication (IVC for highway safety messaging in both vehicular infrastructure and ad hoc networks. Each IVC message, which is assigned a priority based on the safety event urgency, requires different quality of service in terms of communication reliability and average delay. To increase the communication reliability in a broadcast-based IVC, we apply retransmission mechanisms that can provide proportional reliability differentiation for each prioritized message. We evaluate the performance of our proposed protocol using OPNET Modeler, in terms of percentage of successful transmissions and average delay. The protocol performance is evaluated for (1 different system parameters such as the packet size, number of vehicles, and percentage of priority 1 vehicles, and (2 priority-based protocol parameters, such as contention window, interframe spacing and retransmission parameters. The results show that proper protocol parameter settings per priority message result in an efficient solution for priority based broadcast IVC. Moreover, the proposed protocol is fully compatible with both IEEE 802.11 and IEEE 802.11e standards.

  4. An ANFIS-based on B2C electronic commerce transaction

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Juan, E-mail: linjuanliucaihong@qq.com [Department of Mathematics and Computer Science, Fuqing Branch of Fujian Normal University, Fuqing 350300 (China); Liu, Chenlian, E-mail: chenglian.liu@gmail.com [School of Mathematics and Computer Science, Long Yan University, Longyan 364012 (China); Guo, Yongning, E-mail: guoyn@163.com [Fuqing Branch of Fujian Normal University, Fuqing 350300 (China)

    2014-10-06

    The purpose of this study is to use an adaptive-network-based fuzzy inference system to model a fuzzy logic-based system (FIS) for supporting decision-making process in B2C electronic commerce transaction. Firstly we introduce FIS in B2C electronic commerce transaction and ANFIS. Then we use ANFIS to model FIS with different membership functions(MF). Lastly we give a conclusion.

  5. An ANFIS-based on B2C electronic commerce transaction

    Science.gov (United States)

    Lin, Juan; Liu, Chenlian; Guo, Yongning

    2014-10-01

    The purpose of this study is to use an adaptive-network-based fuzzy inference system to model a fuzzy logic-based system (FIS) for supporting decision-making process in B2C electronic commerce transaction. Firstly we introduce FIS in B2C electronic commerce transaction and ANFIS. Then we use ANFIS to model FIS with different membership functions(MF). Lastly we give a conclusion.

  6. Securing Electronic Transactions to Support E-Commerce

    OpenAIRE

    Almunawar, Mohammad Nabil

    2012-01-01

    Many reports regarding online fraud in varieties media create skepticism for conducting transactions online, especially through an open network such as the Internet, which offers no security whatsoever. Therefore, encryption technology is vitally important to support secure e-commerce on the Internet. Two well-known encryption representing symmetric and asymmetric cryptosystems as well as their applications are discussed in this paper. Encryption is a key technology to secure electronic trans...

  7. Scheduling and Topology Design in Networks with Directional Antennas

    Science.gov (United States)

    2017-05-19

    Wireless Mesh Networks , IEEE ICC 2006. [7] E. Gelal, et. al., “Topology Management in Directional Antenna-Equipped Ad Hoc Networks , IEEE Trans. Mobile...Scheduling and Topology Design in Networks with Directional Antennas Thomas Stahlbuhk, Nathaniel M. Jones, Brooke Shrader Lincoln Laboratory...Massachusetts Institute of Technology Lexington, Massachusetts 02420–9108 Abstract—In multihop wireless networks equipped with direc- tional antennas, network

  8. Optimization of IEEE 802.16 PHY Layer for Video Transmission

    Directory of Open Access Journals (Sweden)

    Ehsan Beitmashal

    2010-10-01

    Full Text Available Widespread employment of broadband networks, have been widely excited researchers and producers to develop and optimize this type of networks. This process is not possible, without study and deep preciseness in designing and type of the implementation of system. Recently introducing Worldwide Interoperability for Microwave Access (WiMAX in communication world is invigorating researchers to devote their attempts in way of optimizing this favorite broadband networks. So in this paper, the possibility of transmission and regeneration of information and video pictures with acceptable signal to noise ratio(SNR and bit error rate(BER is provided by simulating physical layer of WiMAX system according to the IEEE 802.16-2004 standard. This simulation is done with MATLAB software and designed for approaching to appropriate quality and throughput in WiMAX networks. Simulation results shows that how video file in 'avi' format have been regenerated with an admissible quality after transmission in virtual designed space based on standard tested with 2-PAM and 64-QAM modulation techniques, simulation also shows how we can use peak signal-to-noise ratio (PSNR of pictures in adaptive modulation and coding (AMC.

  9. IEEE 802154 and ZigBee as enabling technologies for low-power wireless systems with quality-of-service constraints

    CERN Document Server

    Tennina, Stefano; Daidone, Roberta; Alves, Mário; Jurčík, Petr; Severino, Ricardo; Tiloca, Marco; Hauer, Jan-Hinrich; Pereira, Nuno; Dini, Gianluca; Bouroche, Mélanie; Tovar, Eduardo

    2013-01-01

    This book outlines the most important characteristics of IEEE 802.15.4 and ZigBee and how they can be used to engineer Wireless Sensor Network (WSN) systems and applications, with a particular focus on Quality-of-Service (QoS) aspects. It starts by providing a snapshot of the most relevant features of these two protocols, identifying some gaps in the standard specifications. Then it describes several state-of-the-art open-source implementations, models and tools that have been designed by the authors and have been widely used by the international community. The book also outlines the fundamental performance limits of IEEE 802.15.4/ZigBee networks, based on well-sustained analytical, simulation and experimental models, including how to dimension such networks to optimize delay/energy trade-offs.

  10. An Improved Cross-Layering Design for IPv6 Fast Handover with IEEE 802.16m Entry Before Break Handover

    Science.gov (United States)

    Kim, Ronny Yongho; Jung, Inuk; Kim, Young Yong

    IEEE 802.16m is an advanced air interface standard which is under development for IMT-Advanced systems, known as 4G systems. IEEE 802.16m is designed to provide a high data rate and a Quality of Service (QoS) level in order to meet user service requirements, and is especially suitable for mobilized environments. There are several factors that have great impact on such requirements. As one of the major factors, we mainly focus on latency issues. In IEEE 802.16m, an enhanced layer 2 handover scheme, described as Entry Before Break (EBB) was proposed and adopted to reduce handover latency. EBB provides significant handover interruption time reduction with respect to the legacy IEEE 802.16 handover scheme. Fast handovers for mobile IPv6 (FMIPv6) was standardized by Internet Engineering Task Force (IETF) in order to provide reduced handover interruption time from IP layer perspective. Since FMIPv6 utilizes link layer triggers to reduce handover latency, it is very critical to jointly design FMIPv6 with its underlying link layer protocol. However, FMIPv6 based on new handover scheme, EBB has not been proposed. In this paper, we propose an improved cross-layering design for FMIPv6 based on the IEEE 802.16m EBB handover. In comparison with the conventional FMIPv6 based on the legacy IEEE 802.16 network, the overall handover interruption time can be significantly reduced by employing the proposed design. Benefits of this improvement on latency reduction for mobile user applications are thoroughly investigated with both numerical analysis and simulation on various IP applications.

  11. 15th IEEE International Conference on Intelligent Engineering Systems

    CERN Document Server

    Živčák, Jozef; Aspects of Computational Intelligence Theory and Applications

    2013-01-01

    This volume covers the state-of-the art of the research and development in various aspects of computational intelligence and gives some perspective directions of development. Except the traditional engineering areas that contain theoretical knowledge, applications, designs and projects, the book includes the area of use of computational intelligence in biomedical engineering. „Aspects of Computational Intelligence: Theory and Applications” is a compilation of carefully selected extended papers written on the basis of original contributions presented at the 15th IEEE International Conference on Intelligent Engineering Systems 2011, INES 2011 held at June 23.-26. 2011 in AquaCity Poprad, Slovakia.    

  12. Accurate Energy Consumption Modeling of IEEE 802.15.4e TSCH Using Dual-BandOpenMote Hardware.

    Science.gov (United States)

    Daneels, Glenn; Municio, Esteban; Van de Velde, Bruno; Ergeerts, Glenn; Weyn, Maarten; Latré, Steven; Famaey, Jeroen

    2018-02-02

    The Time-Slotted Channel Hopping (TSCH) mode of the IEEE 802.15.4e amendment aims to improve reliability and energy efficiency in industrial and other challenging Internet-of-Things (IoT) environments. This paper presents an accurate and up-to-date energy consumption model for devices using this IEEE 802.15.4e TSCH mode. The model identifies all network-related CPU and radio state changes, thus providing a precise representation of the device behavior and an accurate prediction of its energy consumption. Moreover, energy measurements were performed with a dual-band OpenMote device, running the OpenWSN firmware. This allows the model to be used for devices using 2.4 GHz, as well as 868 MHz. Using these measurements, several network simulations were conducted to observe the TSCH energy consumption effects in end-to-end communication for both frequency bands. Experimental verification of the model shows that it accurately models the consumption for all possible packet sizes and that the calculated consumption on average differs less than 3% from the measured consumption. This deviation includes measurement inaccuracies and the variations of the guard time. As such, the proposed model is very suitable for accurate energy consumption modeling of TSCH networks.

  13. Accurate Energy Consumption Modeling of IEEE 802.15.4e TSCH Using Dual-Band OpenMote Hardware

    Directory of Open Access Journals (Sweden)

    Glenn Daneels

    2018-02-01

    Full Text Available The Time-Slotted Channel Hopping (TSCH mode of the IEEE 802.15.4e amendment aims to improve reliability and energy efficiency in industrial and other challenging Internet-of-Things (IoT environments. This paper presents an accurate and up-to-date energy consumption model for devices using this IEEE 802.15.4e TSCH mode. The model identifies all network-related CPU and radio state changes, thus providing a precise representation of the device behavior and an accurate prediction of its energy consumption. Moreover, energy measurements were performed with a dual-band OpenMote device, running the OpenWSN firmware. This allows the model to be used for devices using 2.4 GHz, as well as 868 MHz. Using these measurements, several network simulations were conducted to observe the TSCH energy consumption effects in end-to-end communication for both frequency bands. Experimental verification of the model shows that it accurately models the consumption for all possible packet sizes and that the calculated consumption on average differs less than 3% from the measured consumption. This deviation includes measurement inaccuracies and the variations of the guard time. As such, the proposed model is very suitable for accurate energy consumption modeling of TSCH networks.

  14. IEEE 802.11-Based Wireless Sensor System for Vibration Measurement

    Directory of Open Access Journals (Sweden)

    Yutaka Uchimura

    2010-01-01

    Full Text Available Network-based wireless sensing has become an important area of research and various new applications for remote sensing are expected to emerge. One of the promising applications is structural health monitoring of building or civil engineering structure and it often requires vibration measurement. For the vibration measurement via wireless network, time synchronization is indispensable. In this paper, we introduce a newly developed time synchronized wireless sensor network system. The system employs IEEE 802.11 standard-based TSF-counter and sends the measured data with the counter value. TSF based synchronization enables consistency on common clock among different wireless nodes. We consider the scale effect on synchronization accuracy and evaluated the effect by taking beacon collisions into account. The scalability issue by numerical simulations is also studied. This paper also introduces a newly developed wireless sensing system and the hardware and software specifications are introduced. The experiments were conducted in a reinforced concrete building to evaluate synchronization accuracy. The developed system was also applied for a vibration measurement of a 22-story steel structured high rise building. The experimental results showed that the system performed more than sufficiently.

  15. Reconfigurable Robust Routing for Mobile Outreach Network Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The early lunar network communications involves the use of a variety of communication channels and networks such as IEEE 802.16, Ka-Band and S-Band satellite...

  16. Real-Time Station Grouping under Dynamic Traffic for IEEE 802.11ah.

    Science.gov (United States)

    Tian, Le; Khorov, Evgeny; Latré, Steven; Famaey, Jeroen

    2017-07-04

    IEEE 802.11ah, marketed as Wi-Fi HaLow, extends Wi-Fi to the sub-1 GHz spectrum. Through a number of physical layer (PHY) and media access control (MAC) optimizations, it aims to bring greatly increased range, energy-efficiency, and scalability. This makes 802.11ah the perfect candidate for providing connectivity to Internet of Things (IoT) devices. One of these new features, referred to as the Restricted Access Window (RAW), focuses on improving scalability in highly dense deployments. RAW divides stations into groups and reduces contention and collisions by only allowing channel access to one group at a time. However, the standard does not dictate how to determine the optimal RAW grouping parameters. The optimal parameters depend on the current network conditions, and it has been shown that incorrect configuration severely impacts throughput, latency and energy efficiency. In this paper, we propose a traffic-adaptive RAW optimization algorithm (TAROA) to adapt the RAW parameters in real time based on the current traffic conditions, optimized for sensor networks in which each sensor transmits packets with a certain (predictable) frequency and may change the transmission frequency over time. The TAROA algorithm is executed at each target beacon transmission time (TBTT), and it first estimates the packet transmission interval of each station only based on packet transmission information obtained by access point (AP) during the last beacon interval. Then, TAROA determines the RAW parameters and assigns stations to RAW slots based on this estimated transmission frequency. The simulation results show that, compared to enhanced distributed channel access/distributed coordination function (EDCA/DCF), the TAROA algorithm can highly improve the performance of IEEE 802.11ah dense networks in terms of throughput, especially when hidden nodes exist, although it does not always achieve better latency performance. This paper contributes with a practical approach to optimizing

  17. Nonblocking Scheduling for Web Service Transactions

    DEFF Research Database (Denmark)

    Alrifai, Mohammad; Balke, Wolf-Tilo; Dolog, Peter

    2007-01-01

    . In this paper, we propose a novel nonblocking scheduling mechanism that is used prior to the actual service invocations. Its aim is to reach an agreement between the client and all participating providers on what transaction processing times have to be expected, accepted, and guaranteed. This enables service......For improved flexibility and concurrent usage existing transaction management models for Web services relax the isolation property of Web service-based transactions. Correctness of the concurrent execution then has to be ensured by commit order-preserving transaction schedulers. However, local...... schedulers of service providers typically do take into account neither time constraints for committing the whole transaction, nor the individual services' constraints when scheduling decisions are made. This often leads to an unnecessary blocking of transactions by (possibly long-running) others...

  18. Private benefits in corporate control transactions

    DEFF Research Database (Denmark)

    Poulsen, Thomas

    with high security benefits, or because the buyer has high private benefits from the control rights that come with the shares? Using voting rights as the vehicle for private benefits, I find that the selling shareholders in block transactions attach more value to private benefits than the buyers. In tender......This paper presents an analytical framework from which it can be inferred whether sellers or buyers in corporate control transactions value private benefits highest. I am thus able to suggest an answer to the question: Are blocks of shares traded because the buyer is a more efficient monitor...... offer transactions, the answer is that private benefits are insignificant to both sides of the transaction. As an alternative measure of the transaction premium, I calculate the abnormal return premium. This represents the stock market's valuation of the transaction. I find that the stock market puts...

  19. Correctness of Concurrent Executions of Closed Nested Transactions in Transactional Memory Systems

    Science.gov (United States)

    Peri, Sathya; Vidyasankar, Krishnamurthy

    A generally agreed upon requirement for correctness of concurrent executions in Transactional Memory systems is that all transactions including the aborted ones read consistent values. Opacity is a recently proposed correctness criterion that satisfies the above requirement. Our first contribution in this paper is extending the opacity definition for closed nested transactions. Secondly, we define conflicts appropriate for optimistic executions which are commonly used in Software Transactional Memory systems. Using these conflicts, we define a restricted, conflict-preserving, class of opacity for closed nested transactions the membership of which can be tested in polynomial time. As our third contribution, we propose a correctness criterion that defines a class of schedules where aborted transactions do not affect consistency of the other transactions. We define a conflict-preserving subclass of this class as well. Both the class definitions and the conflict definition are new for nested transactions.

  20. Long time series of soil moisture obtained using neural networks: application to AMSR-E and SMOS

    Science.gov (United States)

    Rodriguez-Fernandez, Nemesio J.; Kerr, Yann H.; de Jeu, Rcihard A. M.; van der Schalie, Robin; Wigneron, Jean Pierre; Ayaari, Amen al; Dolman, Han; Drusch, Matthias; Mecklenburg, Sussane

    2015-04-01

    Balsamo, G.; Beljaars, A.; Scipal, K.; et al. A revised hydrology for the ECMWF model: Verification from field site to terrestrial water storage and impact in the Integrated Forecast System Journal of hydrometeorology, 2009, 10, 623-643 Kerr, Y. H.; Waldteufel, P.; Richaume, P.; Wigneron et al. The SMOS Soil Moisture Retrieval Algorithm IEEE Transactions on Geoscience and Remote Sensing, 2012, 50, 1384-1403 Mecklenburg, S.; Drusch, M.; Kerr, Y. H. et al. ESA's Soil Moisture and Ocean Salinity Mission: Mission Performance and Operations IEEE Transactions on Geoscience and Remote Sensing, IEEE, 2012, 50, 1354-1366 Owe, M., R.A.M. De Jeu, and T.R.H. Holmes, 2008, "Multi-Sensor Historical Climatology of Satellite-Derived Global Land Surface Moisture", J. Geophys. Res., 113, Rodríguez-Fernández, N. J.; Aires, F.; Richaume, P.; Kerr, Y. H.; et al. M. Soil moisture retrieval using neural networks: application to SMOS IEEE Transactions on Geoscience and Remote Sensing, 2015, submitted

  1. Disintermediation of Inter-Blockchain Transactions

    OpenAIRE

    English, S. Matthew; Orlandi, Fabrizio; Auer, Soeren

    2016-01-01

    Different versions of peer-to-peer electronic cash exist as data represented by separate blockchains. Payments between such systems cannot be sent directly from one party to another without going through a financial institution. Bitcoin provided part of the solution but its utility is limited to intra-blockchain transactions. The benefits are lost if a trusted third party is required to execute inter-blockchain transactions. We propose a solution to the inter-blockchain transaction problem us...

  2. Critical Evaluation of the EJB Transaction Model

    OpenAIRE

    Silaghi, Raul; Strohmeier, Alfred

    2002-01-01

    Enterprise JavaBeans is a widely-used technology that aims at supporting distributed component-based applications written in Java. One of the key features of the Enterprise JavaBeans architecture is the support of declarative distributed transactions, without requiring explicit coding. In this paper, after a brief introduction of the concepts and mechanisms related to the EJB Transaction Model, we provide guidelines for their consistent use. We then evaluate the EJB Transaction Model on an Au...

  3. 75 FR 9142 - Information Reporting for Payments Made in Settlement of Payment Card and Third Party Network...

    Science.gov (United States)

    2010-03-01

    ... in Settlement of Payment Card and Third Party Network Transactions; Hearing AGENCY: Internal Revenue... withholding requirements for payment card and third party network transactions. DATES: The public hearing... card and third party network transactions, was to be held on Wednesday, February 10, 2010 at 10 a.m...

  4. 31 CFR 800.303 - Lending transactions.

    Science.gov (United States)

    2010-07-01

    ... INVESTMENT SECURITY, DEPARTMENT OF THE TREASURY REGULATIONS PERTAINING TO MERGERS, ACQUISITIONS, AND... a typical loan may constitute a covered transaction. (c) An acquisition of voting interest or assets...

  5. 31 CFR 544.404 - Transactions ordinarily incident to a licensed transaction.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Transactions ordinarily incident to a licensed transaction. 544.404 Section 544.404 Money and Finance: Treasury Regulations Relating to Money and... parties required to complete the sale, including transactions by the buyer, broker, transfer agents, banks...

  6. 31 CFR 575.418 - Transactions incidental to a licensed transaction.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Transactions incidental to a licensed transaction. 575.418 Section 575.418 Money and Finance: Treasury Regulations Relating to Money and Finance... activities by other parties required to complete the sale, including transactions by the buyer, brokers...

  7. 31 CFR 546.404 - Transactions ordinarily incident to a licensed transaction.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Transactions ordinarily incident to a licensed transaction. 546.404 Section 546.404 Money and Finance: Treasury Regulations Relating to Money and... transactions by the buyer, broker, transfer agents, banks, etc., provided that such other parties are not...

  8. 31 CFR 585.417 - Transactions incidental to a licensed transaction.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Transactions incidental to a licensed transaction. 585.417 Section 585.417 Money and Finance: Treasury Regulations Relating to Money and Finance... authorizes all activities by other parties required to complete the sale, including transactions by the buyer...

  9. 31 CFR 543.404 - Transactions ordinarily incident to a licensed transaction.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Transactions ordinarily incident to a licensed transaction. 543.404 Section 543.404 Money and Finance: Treasury Regulations Relating to Money and... transactions by the buyer, broker, transfer agents, banks, etc., provided that such other parties are not...

  10. 31 CFR 548.404 - Transactions ordinarily incident to a licensed transaction.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Transactions ordinarily incident to a licensed transaction. 548.404 Section 548.404 Money and Finance: Treasury Regulations Relating to Money and... transactions by the buyer, broker, transfer agents, banks, etc., provided that such other parties are not...

  11. Managing transaction risks in interdependent supply chains: an extended transaction cost economics perspective

    NARCIS (Netherlands)

    Wever, M.; Wognum, P.M.; Trienekens, J.H.; Omta, S.W.F.

    2012-01-01

    The present study examines the management of transaction risks in supply chains. Risk management studies often ignore the wider supply chain context in which individual transactions take place. However, risk management strategies which are suitable to use when only a single transaction is considered

  12. 21 CFR 1404.205 - Why is it important if a particular transaction is a covered transaction?

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Why is it important if a particular transaction is a covered transaction? 1404.205 Section 1404.205 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL... important if a particular transaction is a covered transaction? The importance of a covered transaction...

  13. Proceedings of the IEEE Machine Learning for Signal Processing XVII

    DEFF Research Database (Denmark)

    The seventeenth of a series of workshops sponsored by the IEEE Signal Processing Society and organized by the Machine Learning for Signal Processing Technical Committee (MLSP-TC). The field of machine learning has matured considerably in both methodology and real-world application domains and has...... become particularly important for solution of problems in signal processing. As reflected in this collection, machine learning for signal processing combines many ideas from adaptive signal/image processing, learning theory and models, and statistics in order to solve complex real-world signal processing......, and two papers from the winners of the Data Analysis Competition. The program included papers in the following areas: genomic signal processing, pattern recognition and classification, image and video processing, blind signal processing, models, learning algorithms, and applications of machine learning...

  14. Review of the IEEE Standard for Computerized Operating Procedure Systems

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, J.; Higgins, J.

    2010-02-26

    Increasingly nuclear power plant procedures, such as emergency operating procedures, are being presented in computer form with functionality to support operator use and management of the procedures. The U.S. Nuclear Regulatory Commission (NRC) currently has guidance for the review of computer-based procedures (CBPs); however, there remain CBP functions and human performance issues for which up-to-date guidance is lacking. The Institute of Electrical and Electronics Engineers (IEEE) has initiated a standard development effort to address the human factors engineering (HFE) aspects of CBP systems. When completed, it may provide guidance to supplement the NRC staff's review criteria. The purpose of our study was to evaluate the suitability of the IEEE Standard for use in the NRC's HFE safety reviews of CBP systems and to ensure that the guidance meets the NRC's standard for scientific and engineering rigor used in its own guidance development efforts. We established the following criteria with which to evaluate the Standard: (1) it should meet an existing need of NRC reviewers, (2) it should be based in sound HFE principles, (3) it should be thoroughly peer-reviewed, and (4) it should address CBP-related human performance issues identified in the literature. This report describes the methodology we used to evaluate each criterion. Our evaluation concluded that the Standard generally does meet these criteria, however several areas were identified for which additional clarifications are needed. Thus consideration of the Standard's use by the NRC is supported. The standard evaluation methodology developed in this study can be generally applied to the review of other HFE standards being considered for possible use or endorsement by the NRC.

  15. Programming Idioms for Transactional Events

    Directory of Open Access Journals (Sweden)

    Matthew Kehrt

    2010-02-01

    Full Text Available Transactional events (TE are an extension of Concurrent ML (CML, a programming model for synchronous message-passing. Prior work has focused on TE's formal semantics and its implementation. This paper considers programming idioms, particularly those that vary unexpectedly from the corresponding CML idioms. First, we solve a subtle problem with client-server protocols in TE. Second, we argue that CML's wrap and guard primitives do not translate well to TE, and we suggest useful workarounds. Finally, we discuss how to rewrite CML protocols that use abort actions.

  16. Path loss variation of on-body UWB channel in the frequency bands of IEEE 802.15.6 standard.

    Science.gov (United States)

    Goswami, Dayananda; Sarma, Kanak C; Mahanta, Anil

    2016-06-01

    The wireless body area network (WBAN) has gaining tremendous attention among researchers and academicians for its envisioned applications in healthcare service. Ultra wideband (UWB) radio technology is considered as excellent air interface for communication among body area network devices. Characterisation and modelling of channel parameters are utmost prerequisite for the development of reliable communication system. The path loss of on-body UWB channel for each frequency band defined in IEEE 802.15.6 standard is experimentally determined. The parameters of path loss model are statistically determined by analysing measurement data. Both the line-of-sight and non-line-of-sight channel conditions are considered in the measurement. Variations of parameter values with the size of human body are analysed along with the variation of parameter values with the surrounding environments. It is observed that the parameters of the path loss model vary with the frequency band as well as with the body size and surrounding environment. The derived parameter values are specific to the particular frequency bands of IEEE 802.15.6 standard, which will be useful for the development of efficient UWB WBAN system.

  17. Performance Analysis of a Burst Transmission Mechanism Using Microsleep Operation for Green IEEE 802.11 WLANs

    Directory of Open Access Journals (Sweden)

    Raul Palacios-Trujillo

    2017-07-01

    Full Text Available This paper evaluates the performance of a burst transmission mechanism using microsleep operation to support high energy efficiency in IEEE 802.11 Wireless Local Area Networks (WLANs. This mechanism is an implementation of the IEEE 802.11ac Transmission Opportunity Power Save Mode (TXOP PSM. A device using the TXOP PSM-based mechanism can switch to a low-power sleep state for the time that another device transmits a burst of data frames to a third one. This operation is called microsleep and its feasibility strongly depends on the time and energy consumption that a device incurs in the transitions from and to the sleep state. This paper accounts for the impact of these transitions in the derivation of an analytical model to calculate the energy efficiency of the TXOP PSM-based mechanism under network saturation. Results obtained show that the impact of the transition requirements on the feasibility of microsleep operation can be significant depending on the selected system parameters, although it can be reduced by using burst transmissions. When microsleep operation is feasible, the TXOP PSM-based mechanism can improve the energy efficiency of other legacy mechanisms by up to 424% under high traffic loads.

  18. Empirical investigation on the dependence of TCP downstream throughput on SNR in an IEEE802.11b WLAN system

    Directory of Open Access Journals (Sweden)

    Ikponmwosa Oghogho

    2017-04-01

    Full Text Available The dependence of TCP downstream throughput (TCPdownT on signal to noise ratio (SNR in an IEEE802.11b WLAN system was investigated in various environments and varieties of QoS traffic. TCPdownT was measured for various SNR observed. An Infrastructure based IEEE802.11b WLAN system having networked computers on which measurement software were installed, was set up consecutively in various environments (open corridor, small offices with block walls and plaster boards and free space. Empirical models describing TCPdownT against SNR for different signal ranges (all ranges of signals, strong signals only, grey signals only and weak signals only were statistically generated and validated. As the SNR values changed from high (strong signals through low (grey signals to very low (weak signals, our results show a strong dependence of TCPdownT on the received SNR. Our models showed lower RMS errors when compared with other similar models. We observed RMS errors of 0.6734791 Mbps, 0.472209 Mbps, 0.9111563 Mbps and 0.5764460 Mbps for general (all SNR model, strong signals model, grey signals model and Weak signals model respectively. Our models will provide researchers and WLAN systems users with a tool to estimate the TCP downstream throughput in a real network in various environments by monitoring the received SNR.

  19. Performance analyses and improvements for the IEEE 802.15.4 CSMA/CA scheme with heterogeneous buffered conditions.

    Science.gov (United States)

    Zhu, Jianping; Tao, Zhengsu; Lv, Chunfeng

    2012-01-01

    Studies of the IEEE 802.15.4 Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) scheme have been received considerable attention recently, with most of these studies focusing on homogeneous or saturated traffic. Two novel transmission schemes-OSTS/BSTS (One Service a Time Scheme/Bulk Service a Time Scheme)-are proposed in this paper to improve the behaviors of time-critical buffered networks with heterogeneous unsaturated traffic. First, we propose a model which contains two modified semi-Markov chains and a macro-Markov chain combined with the theory of M/G/1/K queues to evaluate the characteristics of these two improved CSMA/CA schemes, in which traffic arrivals and accessing packets are bestowed with non-preemptive priority over each other, instead of prioritization. Then, throughput, packet delay and energy consumption of unsaturated, unacknowledged IEEE 802.15.4 beacon-enabled networks are predicted based on the overall point of view which takes the dependent interactions of different types of nodes into account. Moreover, performance comparisons of these two schemes with other non-priority schemes are also proposed. Analysis and simulation results show that delay and fairness of our schemes are superior to those of other schemes, while throughput and energy efficiency are superior to others in more heterogeneous situations. Comprehensive simulations demonstrate that the analysis results of these models match well with the simulation results.

  20. Performance Analyses and Improvements for the IEEE 802.15.4 CSMA/CA Scheme with Heterogeneous Buffered Conditions

    Directory of Open Access Journals (Sweden)

    Chunfeng Lv

    2012-04-01

    Full Text Available Studies of the IEEE 802.15.4 Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA scheme have been received considerable attention recently, with most of these studies focusing on homogeneous or saturated traffic. Two novel transmission schemes—OSTS/BSTS (One Service a Time Scheme/Bulk Service a Time Scheme—are proposed in this paper to improve the behaviors of time-critical buffered networks with heterogeneous unsaturated traffic. First, we propose a model which contains two modified semi-Markov chains and a macro-Markov chain combined with the theory of M/G/1/K queues to evaluate the characteristics of these two improved CSMA/CA schemes, in which traffic arrivals and accessing packets are bestowed with non-preemptive priority over each other, instead of prioritization. Then, throughput, packet delay and energy consumption of unsaturated, unacknowledged IEEE 802.15.4 beacon-enabled networks are predicted based on the overall point of view which takes the dependent interactions of different types of nodes into account. Moreover, performance comparisons of these two schemes with other non-priority schemes are also proposed. Analysis and simulation results show that delay and fairness of our schemes are superior to those of other schemes, while throughput and energy efficiency are superior to others in more heterogeneous situations. Comprehensive simulations demonstrate that the analysis results of these models match well with the simulation results.

  1. Cross-layer TCP Performance Analysis in IEEE 802.11 Vehicular Environments

    Directory of Open Access Journals (Sweden)

    T. Janevski

    2014-06-01

    Full Text Available In this paper we provide a performance analysis of TCP in IEEE 802.11 vehicular environments for different well-known TCP versions, such as Tahoe, Reno, New Reno, Vegas, and Sack. The parameters of interest from the TCP side are the number of Duplicate Acknowledgements - DupAck, and the number of Delayed Acknowledgements - DelAck, while on the wireless network side the analyzed parameter is the interface queue - IFQ. We have made the analysis for the worst-case distance scenario for single-hop and worst-case multihop vehicular environments. The results show that the number of wireless hops in vehicular environments significantly reduces the TCP throughput. The best average performances considering all scenarios were obtained for TCP Vegas. However, the results show that the interface queue at wireless nodes should be at least five packets or more. On the other side, due to shorter distances in the vehicular wireless network, results show possible flexibility of using different values for the DupAck without degradation of the TCP throughput. On the other side, the introduction of the DelAck parameter provides enhancement in the average TCP throughput for all TCP versions.

  2. On the Optimization of the IEEE 802.11 DCF: A Cross-Layer Perspective

    Directory of Open Access Journals (Sweden)

    Massimiliano Laddomada

    2010-01-01

    Full Text Available This paper is focused on the problem of optimizing the aggregate throughput of the distributed coordination function (DCF employing the basic access mechanism at the data link layer of IEEE 802.11 protocols. We consider general operating conditions accounting for both nonsaturated and saturated traffic in the presence of transmission channel errors, as exemplified by the packet error rate . The main clue of this work stems from the relation that links the aggregate throughput of the network to the packet rate of the contending stations. In particular, we show that the aggregate throughput ( presents two clearly distinct operating regions that depend on the actual value of the packet rate with respect to a critical value , theoretically derived in this work. The behavior of ( paves the way to a cross-layer optimization algorithm, which proved to be effective for maximizing the aggregate throughput in a variety of network operating conditions. A nice consequence of the proposed optimization framework relies on the fact that the aggregate throughput can be predicted quite accurately with a simple, yet effective, closed-form expression. Finally, theoretical and simulation results are presented in order to unveil, as well as verify, the key ideas.

  3. Maximum Likelihood Estimation of Clock Skew in IEEE 1588 with Fractional Gaussian Noise

    Directory of Open Access Journals (Sweden)

    Chagai Levy

    2015-01-01

    Full Text Available To support system-wide synchronization accuracy and precision in the sub-microsecond range without using GPS technique, the precise time protocol (PTP standard IEEE-1588 v2 is chosen. Recently, a new clock skew estimation technique was proposed for the slave based on a dual slave clock method that assumes that the packet delay variation (PDV in the Ethernet network is a constant delay. However, papers dealing with the Ethernet network have shown that this PDV is a long range dependency (LRD process which may be modeled as a fractional Gaussian noise (fGn with Hurst exponent (H in the range of 0.5

  4. 76 FR 3165 - Proposed Exemptions From Certain Prohibited Transaction Restrictions

    Science.gov (United States)

    2011-01-19

    ... Applicants note that the Transaction proceeded on a more expedited basis than is typical of most... Employee Benefits Security Administration Proposed Exemptions From Certain Prohibited Transaction... proposed exemptions from certain of the prohibited transaction restrictions of the Employee Retirement...

  5. 0011-0030.What is IEEE 754 StandardHow to convert real number ...

    Indian Academy of Sciences (India)

    Home; public; Volumes; reso; 021; 01; 0011-0030.What is IEEE 754 StandardHow to convert real number in binary format using IEEE 754 StandardAn.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News.

  6. A formal analysis of ISO/IEEE P11073-20601 standard of medical device communication

    NARCIS (Netherlands)

    Goga, Nicolae; Costache, Stefania; Moldoveanu, Florica

    2009-01-01

    This article presents the formal work done for the ISO/IEEE P11073-20601 Draft Standard for Health informatics - Personal health device communication - Application profile Optimized exchange protocol. ISO/IEEE 11073 family defines standards for device communication between agents (e.g. blood

  7. Guest editorial: Special issue on selected papers from the IEEE SENSORS 2015 conference

    NARCIS (Netherlands)

    Krijnen, Gijsbertus J.M.; Jiang, Hongrui; Maeda, Ryutaro; Vellekoop, M.H.

    2016-01-01

    Over the years, the IEEE SENSORS Conference has become one of the premier, true international, conferences on anything that has to do with sensors, ranging from principles, design and fabrication to interfacing, data-extraction, applications, etc. The IEEE SENSORS 2015 Conference was held in Bushan,

  8. Introduction to the Theory of Nested Transactions,

    Science.gov (United States)

    1986-07-01

    since the common terminology for access and non-access transactions is of great benefit in unifying the statements and proofs of our results. ’lhus...34Guardians and Actions: Linguistic Support for Robust, 60 Distributed Programs", ACAI Transactions on Programming Ianguages and Systems 5. 3, (July

  9. 76 FR 40779 - Retail Foreign Exchange Transactions

    Science.gov (United States)

    2011-07-12

    ... regulations do not apply to traditional foreign currency forwards, spots, or swap transactions that an insured... requirements for foreign currency futures, options on futures, and options that an insured depository... on other foreign currency transactions that are functionally or economically similar, including so...

  10. Integrated Telecommunications Systems and Instructional Transaction.

    Science.gov (United States)

    Saba, Farhad

    1988-01-01

    Discussion of how learner and teacher communicate in distance education focuses on Morre's concept of transactional distance in light of recent developments in telecommunications. Integrated telecommunications systems are described, adult learning and instructional transactions are discussed, and system dynamics are presented as a tool for…

  11. The Transactive Nature of Therapeutic Communication.

    Science.gov (United States)

    Tubbs, Stewart L.

    Therapeutic communication, or interaction which provokes personal insight or reorientation, can be best understood as a transactive, rather than linear, interrelationship between people or groups. Two practical responses to "pathological" communication patterns illustrate the validity of the transactional communication theory: the…

  12. The transactional approach in company boundaries

    Directory of Open Access Journals (Sweden)

    Bruno Chaihuaque Dueñas

    2009-12-01

    Full Text Available This article shows the relationship between market and firms through the theory of transactional cost and the relationsthat determine the structure and boundaries of the firm. Using the assumptions from the transactional cost approach,this article proposes some variables that determine optimal organizational structures and their boundaries.

  13. On the Connectivity and Multihop Delay of Ad Hoc Cognitive Radio Networks

    Science.gov (United States)

    2011-04-01

    K. Jagannathan, and E. Modiano , “Delay analysis of maximum weight scheduling in wireless ad hoc networks,” in Proc. IEEE CISS, March 2009, pp. 389...394. [11] M. J. Neely and E. Modiano , “Capacity and delay tradeoffs for ad hoc mobile networks,” IEEE Trans. Inf. Theory, vol. 51, no. 6, pp. 1917–1937

  14. Distributed Management of Concurrent Web Service Transactions

    DEFF Research Database (Denmark)

    Alrifai, Mohammad; Dolog, Peter; Balke, Wolf-Tilo

    2009-01-01

    of conventional ACID transaction models for Web services far from being straightforward. Current Web service transaction models relax the isolation property and rely on compensation mechanisms to ensure atomicity of business transactions in the presence of service failures. However, ensuring consistency......Business processes involve dynamic compositions of interleaved tasks. Therefore, ensuring reliable transactional processing of Web services is crucial for the success of Web service-based B2B and B2C applications. But the inherent autonomy and heterogeneity of Web services render the applicability...... in the open and dynamic environment of Web services, where interleaving business transactions enter and exit the system independently, remains an open issue. In this paper, we address this problem and propose an architecture that supports concurrency control on the Web services level. An extension...

  15. Evaluasi Kinerja Layanan IPTV pada Jaringan Testbed WiMAX Berbasis Standar IEEE 802.16-2004

    Directory of Open Access Journals (Sweden)

    Prasetiyono Hari Mukti

    2015-09-01

    Full Text Available In this paper, a performance evaluation for IPTV Services over WiMAX testbed based on IEEE Standard 802.16-2004 will be described. The performance of the proposed system is evaluated in terms of delay, jitter, throughput and packet loss. Service performance evaluations are conducted on network topology of point-to-point in the variation of background traffic with different scheduling types. Background traffic is injected into the system to give the sense that the proposed system has variation traffic load. Scheduling type which are used in this paper are Best Effort (BE, Non-Real-Time Polling Service (nrtPS, Real-Time Polling Service (rtPS and Unsolicited Grant Service (UGS. The expemerintal results of IPTV service performance over the testbed network show that the maximum average of delay, jitter, packet loss and jitter are 16.581 ms, 58.515 ms, 0.67 Mbps dan 10.96%, respectively.

  16. The Combined Effect of Signal Strength and Background Traffic Load on Speech Quality in IEEE 802.11 WLAN

    Directory of Open Access Journals (Sweden)

    P. Pocta

    2011-04-01

    Full Text Available This paper deals with measurements of the combined effect of signal strength and background traffic load on speech quality in IEEE 802.11 WLAN. The ITU-T G.729AB encoding scheme is deployed in this study and the Distributed Internet Traffic Generator (D-ITG is used for the purpose of background traffic generation. The speech quality and background traffic load are assessed by means of the accomplished PESQ algorithm and Wireshark network analyzer, respectively. The results show that background traffic load has a bit higher impact on speech quality than signal strength when both effects are available together. Moreover, background traffic load also partially masks the impact of signal strength. The reasons for those findings are particularly discussed. The results also suggest some implications for designers of wireless networks providing VoIP service.

  17. Social networks and factor markets

    DEFF Research Database (Denmark)

    Abay, Kibrom Araya; Kahsay, Goytom Abraha; Berhane, Guush

    2017-01-01

    We investigate the role of an indigenous social network in Ethiopia, the iddir, in facilitating factor market transactions among smallholder farmers. We use a detailed longitudinal household survey data and employ a fixed effects estimation to identify the effect of iddir membership on factor...... market transactions among farmers. We find that joining an iddir network improves households’ access to land, labour and credit transactions. Our findings also hint that iddir networks may crowd-out borrowing from local moneylenders (locally referred as ‘Arata Abedari’), a relatively expensive credit...

  18. Technological Perspectives for Air Base Communications.

    Science.gov (United States)

    1985-10-01

    is published in Local Computer Networks, 2d. ed., IEEE Computer Society , 1981. \\ %-..o -15- (a) Long-haul Long-haul Long-haul network 1 network 2...34 IEEE/CIPHER Newsletter, IEEE Computer Society , Silver Spring, Maryland, January 1985, p. 3. . . . ... , - - -. .. ... t... cashless transactions, %.% electronic mail, comprehensive telephone services, and access to commercial databases could also prove useful for the

  19. IEEE 802.11ah: A Technology to Face the IoT Challenge

    Directory of Open Access Journals (Sweden)

    Victor Baños-Gonzalez

    2016-11-01

    Full Text Available Since the conception of the Internet of things (IoT, a large number of promising applications and technologies have been developed, which will change different aspects in our daily life. This paper explores the key characteristics of the forthcoming IEEE 802.11ah specification. This future IEEE 802.11 standard aims to amend the IEEE 802.11 legacy specification to support IoT requirements. We present a thorough evaluation of the foregoing amendment in comparison to the most notable IEEE 802.11 standards. In addition, we expose the capabilities of future IEEE 802.11ah in supporting different IoT applications. Also, we provide a brief overview of the technology contenders that are competing to cover the IoT communications framework. Numerical results are presented showing how the future IEEE 802.11ah specification offers the features required by IoT communications, thus putting forward IEEE 802.11ah as a technology to cater the needs of the Internet of Things paradigm.

  20. IEEE 802.11ah: A Technology to Face the IoT Challenge.

    Science.gov (United States)

    Baños-Gonzalez, Victor; Afaqui, M Shahwaiz; Lopez-Aguilera, Elena; Garcia-Villegas, Eduard

    2016-11-22

    Since the conception of the Internet of things (IoT), a large number of promising applications and technologies have been developed, which will change different aspects in our daily life. This paper explores the key characteristics of the forthcoming IEEE 802.11ah specification. This future IEEE 802.11 standard aims to amend the IEEE 802.11 legacy specification to support IoT requirements. We present a thorough evaluation of the foregoing amendment in comparison to the most notable IEEE 802.11 standards. In addition, we expose the capabilities of future IEEE 802.11ah in supporting different IoT applications. Also, we provide a brief overview of the technology contenders that are competing to cover the IoT communications framework. Numerical results are presented showing how the future IEEE 802.11ah specification offers the features required by IoT communications, thus putting forward IEEE 802.11ah as a technology to cater the needs of the Internet of Things paradigm.

  1. 48 CFR 52.223-16 - IEEE 1680 Standard for the Environmental Assessment of Personal Computer Products.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false IEEE 1680 Standard for the... CONTRACT CLAUSES Text of Provisions and Clauses 52.223-16 IEEE 1680 Standard for the Environmental Assessment of Personal Computer Products. As prescribed in 23.706(b)(1), insert the following clause: IEEE...

  2. An Asynchronous IEEE Floating-Point Arithmetic Unit

    Directory of Open Access Journals (Sweden)

    Joel R. Noche

    2007-12-01

    Full Text Available An asynchronous floating-point arithmetic unit is designed and tested at the transistor level usingCadence software. It uses CMOS (complementary metal oxide semiconductor and DCVS (differentialcascode voltage switch logic in a 0.35 µm process using a 3.3 V supply voltage, with dual-rail data andsingle-rail control signals using four-phase handshaking.Using 17,085 transistors, the unit handles single-precision (32-bit addition/subtraction, multiplication,division, and remainder using the IEEE 754-1985 Standard for Binary Floating-Point Arithmetic, withrounding and other operations to be handled by separate hardware or software. Division and remainderare done using a restoring subtractive algorithm; multiplication uses an additive algorithm. Exceptionsare noted by flags (and not trap handlers and the output is in single-precision.Previous work on asynchronous floating-point arithmetic units have mostly focused on single operationssuch as division. This is the first work to the authors' knowledge that can perform floating-point addition,multiplication, division, and remainder using a common datapath.

  3. Adaptive Sleep Scheduling for Health Monitoring System Based on the IEEE 802.15.4 Standard

    Directory of Open Access Journals (Sweden)

    Nurul Fahmi

    2016-08-01

    Full Text Available In the recent years, Wireless Sensor Networks (WSNs have become a very popular technology for research in various fields. One of the technologies which is developed using WSN is environmental health monitoring. However, there is a problem when we want to optimize the performance of the environmental health monitoring such as the limitation of the energy. In this paper, we proposed a method for the environmental health monitoring using the fuzzy logic approach according to the environmental health conditions. We use that condition to determine the sleep time in the system based on IEEE 802.15.4 standard protocol. The main purpose of this method is to extend the life and minimize the energy consumption of the battery. We implemented this system in the real hardware test-bed using temperature, humidity, CO and CO2 sensors. We compared the performance without sleep scheduling, with sleep scheduling and adaptive sleep scheduling. The power consumption spent during the process of testing without sleep scheduling is 52%, for the sleep scheduling is 13%, while using the adaptive sleep scheduling is around 7%. The users also can monitor the health condition via mobile phone or web-based application, in real-time anywhere and anytime.

  4. IEEE-802.15.4-based low-power body sensor node with RF energy harvester.

    Science.gov (United States)

    Tran, Thang Viet; Chung, Wan-Young

    2014-01-01

    This paper proposes the design and implementation of a low-voltage and low-power body sensor node based on the IEEE 802.15.4 standard to collect electrocardiography (ECG) and photoplethysmography (PPG) signals. To achieve compact size, low supply voltage, and low power consumption, the proposed platform is integrated into a ZigBee mote, which contains a DC-DC booster, a PPG sensor interface module, and an ECG front-end circuit that has ultra-low current consumption. The input voltage of the proposed node is very low and has a wide range, from 0.65 V to 3.3 V. An RF energy harvester is also designed to charge the battery during the working mode or standby mode of the node. The power consumption of the proposed node reaches 14 mW in working mode to prolong the battery lifetime. The software is supported by the nesC language under the TinyOS environment, which enables the proposed node to be easily configured to function as an individual health monitoring node or a node in a wireless body sensor network (BSN). The proposed node is used to set up a wireless BSN that can simultaneously collect ECG and PPG signals and monitor the results on the personal computer.

  5. An SNMP-based solution to enable remote ISO/IEEE 11073 technical management.

    Science.gov (United States)

    Lasierra, Nelia; Alesanco, Alvaro; García, José

    2012-07-01

    This paper presents the design and implementation of an architecture based on the integration of simple network management protocol version 3 (SNMPv3) and the standard ISO/IEEE 11073 (X73) to manage technical information in home-based telemonitoring scenarios. This architecture includes the development of an SNMPv3-proxyX73 agent which comprises a management information base (MIB) module adapted to X73. In the proposed scenario, medical devices (MDs) send information to a concentrator device [designated as compute engine (CE)] using the X73 standard. This information together with extra information collected in the CE is stored in the developed MIB. Finally, the information collected is available for remote access via SNMP connection. Moreover, alarms and events can be configured by an external manager in order to provide warnings of irregularities in the MDs' technical performance evaluation. This proposed SNMPv3 agent provides a solution to integrate and unify technical device management in home-based telemonitoring scenarios fully adapted to X73.

  6. TRANSACTIONAL AND TRANSFORMATIONAL LEADERSHIP: DEVELOPMENT THROUGH CHANGES

    Directory of Open Access Journals (Sweden)

    Srđan Nikezić

    2012-09-01

    Full Text Available The success and rewarding are mostly expressed in business performance at the end of the year. Transactional and transformational leadership as a new paradigm of quality effects on creation of roles and processes in the organizat ion. From the leaders are expected to use leadership as a process of ensuring the long - term goals of the organization, especially in turbulent competitive environment. Therefore, this paper points out the impact of leadership competencies through transactional and trans formational leadership, characteristics and processes that show different levels of participation of transformation and transactional leadership of organizations.

  7. Entrepreneurship, Transaction Costs, and Resource Attributes

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    This paper responds to Kim and Mahoney's "How Property Rights Economics Furthers the Resource-Based View: Resources, Transaction Costs and Entrepreneurial Discovery" (a comment on Foss and Foss, 2005). While we agree with many of their arguments, we argue that they fail to recognize how exactly...... transaction costs and property rights shape the process of entrepreneurial discovery. We provide a sketch of the mechanisms that link entrepreneurship, property rights, and transaction costs in a resource-based setting, contributing further to the attempt to take the RBV in a more dynamic direction....

  8. Security of M-Commerce transactions

    Directory of Open Access Journals (Sweden)

    Ion IVAN

    2013-07-01

    Full Text Available In this material electronic market are defined. How they are structured. Security in E-Commerce applications is very important both at the administrative level and from the user perspective. The new trend in the field is the M-commerce that involves making purchases through mobile devices. And for M-commerce transactions the security is a very important thing. Here's how to analyze the security of M-commerce transactions and ways to increase security for these transactions taking into account the organization of M-Commerce applications, software used, hardware used and other important issues in the development of these applications.

  9. Entrepreneurship, transaction costs, and resource attributes

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2006-01-01

    This paper responds to Kim and Mahoney's "How Property Rights Economics Furthers the Resource-Based View: Resources, Transaction Costs and Entrepreneurial Discovery" (a comment on Foss and Foss, 2005). While we agree with many of their arguments, we argue that they fail to recognise how exactly t...... transaction costs shape the process of entrepreneurial discovery. We provide a sketch of the mechanisms that link entrepreneurship, property rights, and transaction costs in a resource-based setting, contributing further to the attempt to take the RBV in a more dynamic direction....

  10. Accounting costs of transactions in real estate

    DEFF Research Database (Denmark)

    Stubkjær, Erik

    2005-01-01

    in relating theoretical conceptualizations of transaction costs to national accounting and further to the identification and quantification of actions on units of real estate. The notion of satellite accounting of the System of National Accounts is applied to the segment of society concerned with changes......The costs of transactions in real estate is of importance for households, for investors, for statistical services, for governmental and international bodies concerned with the efficient delivery of basic state functions, as well as for research. The paper takes a multi-disciplinary approach...... in real estate. The paper ends up with an estimate of the cost of a major real property transaction in Denmark....

  11. 19 CFR 152.103 - Transaction value.

    Science.gov (United States)

    2010-04-01

    ... advantage of the cash discount. The transaction value is $98, the price actually paid or payable. (2..., in the United States, of copyrights and trademarks related to the imported merchandise generally will...

  12. 77 FR 64663 - Iranian Transactions Regulations

    Science.gov (United States)

    2012-10-22

    ... transaction or dealing includes but is not limited to purchasing, selling, transporting, swapping, brokering... U.S. person holding funds, such as currency, bank deposits, or liquidated financial obligations...

  13. Equity Markets, Transactions Costs, and Capital Accumulation

    National Research Council Canada - National Science Library

    Starr, Ross M; Bencivenga, Valerie R; Smith, Bruce D

    1996-01-01

    Poorly developed equity markets inhibit the transfer of capital ownership. Moreover, the costs of transacting in equity markets affect not just the level of investment, but the kinds of investments that are undertaken...

  14. Nurse managers as transformational and transactional leaders.

    Science.gov (United States)

    McGuire, Elaine; Kennerly, Susan M

    2006-01-01

    Nurse managers demonstrating transformational leadership are more likely than transactional leaders to have committed staff nurse followers. Committed followers exert extra effort, thus improving unit performance and enhancing the organization's competitive advantage.

  15. Guarding against Collateral Damage during Chromatin Transactions

    DEFF Research Database (Denmark)

    Altmeyer, Matthias; Lukas, Jiri

    2013-01-01

    Signal amplifications are vital for chromatin function, yet they also bear the risk of transforming into unrestrained, self-escalating, and potentially harmful responses. Examples of inbuilt limitations are emerging, revealing how chromatin transactions are confined within physiological boundaries....

  16. How large customer direct power transaction mode give consideration to power generation cleaning and power saving

    Science.gov (United States)

    Liu, Yu; Zeng, Ming; Liu, Wei; Li, Ran

    2017-05-01

    The so-called Large Customers' Direct Power Transaction, refers to the mode that the users on high voltage level, or being seized of hold the large power or independent power distribution, have the qualification of purchasing electricity directly from the generation companies and pay reasonable electricity transmission and distribution fee to the power network enterprises because the transaction is through its transmission channel. The Direct Purchase promotes the marketization level of electricity trading, but there are some problems in its developing process, especially whether promotes the green optimal allocation of power resources, this paper aims to explore the solution.

  17. Settling Payments Fast and Private: Efficient Decentralized Routing for Path-Based Transactions

    OpenAIRE

    Roos, Stefanie; Moreno-Sanchez, Pedro; Kate, Aniket; Goldberg, Ian

    2017-01-01

    Path-based transaction (PBT) networks, which settle payments from one user to another via a path of intermediaries, are a growing area of research. They overcome the scalability and privacy issues in cryptocurrencies like Bitcoin and Ethereum by replacing expensive and slow on-chain blockchain operations with inexpensive and fast off-chain transfers. In the form of credit networks such as Ripple and Stellar, they also enable low-price real-time gross settlements across different currencies. F...

  18. Sale Leaseback Transactions: Price Premiums and Market Efficiency

    OpenAIRE

    Sirmans, C.F.; Slade, Barrett A.

    2010-01-01

    Sale-leaseback transactions are ubiquitous in real estate markets in the United States with annual volume estimated to be greater than $7 billion. However, there is no evidence concerning the price impact of such transactional arrangements. Using a data set of sale-leaseback transactions, this study examines the price impact on commercial property transactions across seven markets. The findings reveal that transactions structured as saleleasebacks occur at significantly higher prices than mar...

  19. Conceptualizing and Measuring Transformational and Transactional Leadership

    DEFF Research Database (Denmark)

    Jensen, Ulrich Thy; Andersen, Lotte Bøgh; Ladegaard, Louise

    2016-01-01

    Existing conceptualizations and measures of transformational and transactional leadership have unclear theoretical bases, confound leadership and its effects, and are not necessarily suitable for public organizations. Overcoming these problems is necessary to test how leadership affects performance....... Many public administration scholars apply the concepts, emphasizing the need to ensure that the concepts are applicable in both public and private organizations. The article reconceptualizes transformational and transactional leadership and develops and tests revised measures that can be employed...

  20. Related Party Transactions and Earnings Management

    OpenAIRE

    Kuan, Linvani; Tower, Greg; Rusmin, Rusmin; Zahn, J-L.W. Mitchell Van der

    2010-01-01

    This study examines the association between related party transactions and earnings man-agement, based on a sample of 50 Indonesian publicly listed companies for the periods ending 2004 and 2005. The hypothesis developed in this study draw on past literature and the tenets of agency theory which suggest that the existence of related party transactions represent potential conflict of interest which may results in earnings management and appropriation by controlling shareholder to minority shar...

  1. Mobile transactions over NFC and GSM

    OpenAIRE

    Saeed, MQ; Walter, C.; Pourghomi, P; G. Ghinea

    2014-01-01

    Dynamic relationships between Near Field Communication (NFC) ecosystem players in a monetary transaction make them partners in a way that they sometimes require to share access permission to applications that are running in the service environment. One of the technologies that can be used to ensure secure NFC transactions is cloud computing. This offers a wider range of advantages than the use of only a Secure Element (SE) in an NFC enabled mobile phone. In this paper, we propose a protocol f...

  2. Transactional theory in leadership and work motivation

    OpenAIRE

    Pavšič, Tine

    2014-01-01

    The thesis presents transactional theory in leadership and motivational theory, self-determination theory. Theoretical part presents components of self-determination continuum, work extrinsic and intrinsic motivation, components of transformational and transactional leadership and researches which are exploring this components. The empirical part of the thesis includes research, which presents the correlation between leadership styles and work self-determination index. Moreover, it presen...

  3. Reactions to Corporate Insider’s Transactions

    DEFF Research Database (Denmark)

    Rose, Caspar; Søpstad, Nicolai

    2015-01-01

    We test the impact on security prices of top manager’s requirement’s to disclose their own share transactions in the firm. Specifically we study whether buy or sales transactions convey relevant information for market participants thereby studying the effects of legal stock market disclosure rules......, which to our knowledge have not been noticed already by others. Thus, our event study shows that the Danish stock market seems to be efficient in the semi-strong from....

  4. The Secret Life of Mundane Transaction Costs

    OpenAIRE

    Richard N. Langlois

    2005-01-01

    Transaction costs, one often hears, are the economic equivalent of friction in physical systems. Like physicists, economists can sometimes neglect friction in formulating theories; but like engineers, they can never neglect friction in studying how the system actually does let alone should work. Interestingly, however, the present-day economics of organization also ignores friction. That is, almost single-mindedly, the literature analyzes transactions from the point of view of misaligned ince...

  5. Mutual authentication in electronic commerce transactions.

    OpenAIRE

    2008-01-01

    Electronic commerce is a large and ever growing industry. Online transactions are returning ever-growing revenues to electronic merchants. The e-commerce industry is still facing a range of problems concerning the process of completion of online transactions. Such problems are connected to consumer fears dealing with the identity of online merchants, their security pre- cautions and methods for accepting online payments. This thesis develops and presents a Mutual Authentication Model (MAM), w...

  6. Theorizing E-Commerce Business Models: On the Impact of Partially and Fully Supported Transaction Phases on Customer Satisfaction and Loyalty

    Directory of Open Access Journals (Sweden)

    Maria Madlberger

    2017-03-01

    Full Text Available Although considerable research has been conducted on the definition and classification of e-commerce business models, little research has integrated the support and impact of distinct transaction phases within e-commerce business models. Indeed, any channel design decisions depend on the arrangement of the three transaction phases, viz. information phase, agreement phase and fulfilment phase. Whereas in literature, a complete support of transaction phases is implicitly assumed, in practice, e-commerce firms exist that consciously do not support all three transaction phases through the online channel. In cases for which only certain phases are supported in one channel, the customer is required to switch to another channel to complete the transaction. To gain an initial understanding of the relevance of transaction phases, we examine the influence of transaction phase support in one channel on satisfaction and reuse intention of an e-commerce website under consideration of users’ prior experiences. We conduct a laboratory experiment involving two e-commerce business models that differ only in the number of supported transaction phases via the online channel. Empirical data was analysed using a Bayesian network approach. Our analysis indicates the types of users who value partial support compared to those users who prefer full support of transaction phases. The results will assist firms in meeting future challenges regarding user engagement and attraction to their online stores.

  7. 0011-0030.How to make an abstract in IEEE Format for ...

    Indian Academy of Sciences (India)

    Home; public; Volumes; reso; 021; 01; 0011-0030.How to make an abstract in IEEE Format for AvishkarMulticultural Night in IEEE R10 Student Congress 2009Performances.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube · Twitter · Facebook ...

  8. Invisible watermarking optical camera communication and compatibility issues of IEEE 802.15.7r1 specification

    Science.gov (United States)

    Le, Nam-Tuan

    2017-05-01

    Copyright protection and information security are two most considered issues of digital data following the development of internet and computer network. As an important solution for protection, watermarking technology has become one of the challenged roles in industry and academic research. The watermarking technology can be classified by two categories: visible watermarking and invisible watermarking. With invisible technique, there is an advantage on user interaction because of the visibility. By applying watermarking for communication, it will be a challenge and a new direction for communication technology. In this paper we will propose one new research on communication technology using optical camera communications (OCC) based invisible watermarking. Beside the analysis on performance of proposed system, we also suggest the frame structure of PHY and MAC layer for IEEE 802.15.7r1 specification which is a revision of visible light communication (VLC) standardization.

  9. IEEE 802.15.4 Frame Aggregation Enhancement to Provide High Performance in Life-Critical Patient Monitoring Systems.

    Science.gov (United States)

    Akbar, Muhammad Sajjad; Yu, Hongnian; Cang, Shuang

    2017-01-28

    In wireless body area sensor networks (WBASNs), Quality of Service (QoS) provision for patient monitoring systems in terms of time-critical deadlines, high throughput and energy efficiency is a challenging task. The periodic data from these systems generates a large number of small packets in a short time period which needs an efficient channel access mechanism. The IEEE 802.15.4 standard is recommended for low power devices and widely used for many wireless sensor networks applications. It provides a hybrid channel access mechanism at the Media Access Control (MAC) layer which plays a key role in overall successful transmission in WBASNs. There are many WBASN's MAC protocols that use this hybrid channel access mechanism in variety of sensor applications. However, these protocols are less efficient for patient monitoring systems where life critical data requires limited delay, high throughput and energy efficient communication simultaneously. To address these issues, this paper proposes a frame aggregation scheme by using the aggregated-MAC protocol data unit (A-MPDU) which works with the IEEE 802.15.4 MAC layer. To implement the scheme accurately, we develop a traffic patterns analysis mechanism to understand the requirements of the sensor nodes in patient monitoring systems, then model the channel access to find the performance gap on the basis of obtained requirements, finally propose the design based on the needs of patient monitoring systems. The mechanism is initially verified using numerical modelling and then simulation is conducted using NS2.29, Castalia 3.2 and OMNeT++. The proposed scheme provides the optimal performance considering the required QoS.

  10. Zero tolerance for incorrect data: Best practices in SQL transaction programming

    Science.gov (United States)

    Laiho, M.; Skourlas, C.; Dervos, D. A.

    2015-02-01

    DBMS products differ in the way they support even the basic SQL transaction services. In this paper, a framework of best practices in SQL transaction programming is given and discussed. The SQL developers are advised to experiment with and verify the services supported by the DBMS product used. The framework has been developed by DBTechNet, a European network of teachers, trainers and ICT professionals. A course module on SQL transactions, offered by the LLP "DBTech VET Teachers" programme, is also presented and discussed. Aims and objectives of the programme include the introduction of the topics and content of SQL transactions and concurrency control to HE/VET curricula and addressing the need for initial and continuous training on these topics to in-company trainers, VET teachers, and Higher Education students. An overview of the course module, its learning outcomes, the education and training (E&T) content, virtual database labs with hands-on self-practicing exercises, plus instructions for the teacher/trainer on the pedagogy and the usage of the course modules' content are briefly described. The main principle adopted is to "Learn by verifying in practice" and the transactions course motto is: "Zero Tolerance for Incorrect Data".

  11. A Nationwide Experimental Multi-Gigabit Network

    Science.gov (United States)

    2003-03-01

    34Enabling Network-Aware Applications", Proceedings of the 10th IEEE Symposium on High Performance Distributed Computing ( HPDC -10), August 2001, LBNL...Proceedings of the IEEE High Performance Distributed Computing con- ference ( HPDC -7), July 1998, LBNL-42611 [29] Tierney, B. J. Lee, B. Crowley, M...Computing conference ( HPDC -8), August 1999, LBNL-42896. http://www-didc.lbl.gov/DPSS/ [30] Watson, R., Coyne, R.,“The Parallel I/O Architecture of

  12. Management Control of Market Transactions: The Relation Between Transaction Characteristics, Incomplete Contract Design and Subsequent Performance

    NARCIS (Netherlands)

    Anderson, S.W.; Dekker, H.C.

    2005-01-01

    Using an unusually comprehensive database on 858 transactions for information technology products and accompanying services, we study how close partners who are exposed to opportunistic hazards structure and control a significant transaction. We analyze data on the terms of contracting to determine

  13. Extending Software Transactional Memory in Clojure with Side-Effects and Transaction Control

    DEFF Research Database (Denmark)

    Jensen, Søren Kejser; Thomsen, Lone Leth

    2016-01-01

    In conjunction with the increase of multi-core processors the use of functional programming languages has increased in recent years. The functional language Clojure has concurrency as a core feature, and provides Software Transactional Memory (STM) as a substitute for locks. Transactions in Cloju...

  14. Who Spends Money to Play for Free? Identifying Who Makes Micro-transactions on Social Casino Games (and Why).

    Science.gov (United States)

    Kim, Hyoun S; Hollingshead, Samantha; Wohl, Michael J A

    2017-06-01

    Social casino games are online gambling-like games found on social networking sites. They are initially free to play, however, players are encouraged to make micro-transactions (i.e., in-game purchases) for additional game credits or functionality. As a result, they generate billions of dollars in revenue. Yet, little is known as to who purchases virtual credits, let alone why. In the present research, we assessed whether there are individual differences (impulsivity, reward sensitivity, competitiveness, and problem gambling severity) between who is and who is not likely to make micro-transactions during social casino game play. Moreover, we examined possible motivations for making micro-transactions (e.g., extend play, win back lost credits) and whether the individual difference variables of interest predict reported motivation(s) for making micro-transactions. Results showed that social casino gamers who engaged in micro-transactions reported significantly higher levels of impulsivity, reward sensitivity and problem gambling severity, but not competitiveness. In terms of motivation to make micro-transactions, desire to extend play was endorsed most frequently, followed by a desire to access additional features, chasing lost credits, and to speed up play. Lastly, among participants who made micro-transactions, reward sensitivity predicted making micro-transactions to chase lost credits. These results suggest the personality make-up of social casino gamers is important to understand who is likely to make micro-transactions as well as their motivation to do so-information that could prove useful for regulation of the industry.

  15. Assessing Transaction Environment Conditions for Investment and Construction

    Directory of Open Access Journals (Sweden)

    Mishlanova Marina

    2016-01-01

    Full Text Available This paper contains characteristic description of the transaction-based approach and identifies problems of studying the transaction envi-ronment for investments and construction. It also discusses the results of transaction cost analysis in the real estate sector, and assessment of the business environment in Russia. The authors present indirect assessment of transaction environment through the economic freedom index, detailed particularly for Russia; they demonstrate the transaction environment structure and offer methodological recommendations on evaluation of transaction environment for investment and construction.

  16. SELF-POWERED WIRELESS SENSOR NODE POWER MODELING BASED ON IEEE 802.11 COMMUNICATION PROTOCOL

    Energy Technology Data Exchange (ETDEWEB)

    Vivek Agarwal; Raymond A. DeCarlo; Lefteri H. Tsoukalas

    2016-04-01

    considerations that must also be taken into account when computing the power consumption associated with each task. The considerations includes: number of events occurring in a fixed active time period and the duration of each event, event-information processing time, total communication time, number of retransmission, etc. Additionally, at the network level the communication of information data packets between WSNs involves collisions, latency, andretransmission, which result in unanticipated power losses. This paper presents stochastic modeling of power demand for a schedule-driven WSN utilizing Institute of Electrical and Electronics Engineers, IEEE, 802.11 communication protocols. The model captures the generic operation of a schedule-driven WSN when an external event occurs, i.e., sensing, following by processing, and followed by communication. The results are verified via simulation.

  17. Rede de controle em ambiente hospitalar: um protocolo multiciclos para automação hospitalar sobre IEEE 802.3 com IGMP Snooping

    OpenAIRE

    Valentim, Ricardo Alexsandro de Medeiros; Morais, Antônio Higor de Morais; Souza, Vinícius Samuel Valério de; Araújo Junior, Hélio Batista de; Brandão, Gláucio Bezerra; Guerreiro, Ana Maria Guimarães

    2009-01-01

    VALENTIM, R. A. M. ; MORAIS, A. H. F. ; SOUZA, V. S. V ; ARAUJO JUNIOR, H. B. ; BRANDAO, G. B. ; GUERREIRO, A. M. G. . Rede de Controle em Ambiente Hospitalar: um protocolo multiciclos para automação hospitalar sobre IEEE 802.3 com IGMP Snooping. Revista Ciência e Tecnologia, v. 11, p. 19, 2009 This paper presents a Multicycles Protocol for Hospital Automation (MPHA) which works over multicast addressing and use a Master-Slave architecture. The protocol creates a segmented logical network...

  18. Assessing and Improving Operational Resilience of Critical Infrastructures and Other Systems: An INFORMS TutORial

    Science.gov (United States)

    2014-11-09

    multicommodity flow network interdiction problems. IIE Transactions 39(1) 15–26. Mukherjee, B., B. Banerjee, S. Ramamurthy, A. Mukherjee. 1996. Some principles for...designing a wide-area WDM optical network. IEEE/ACM Transactions on Networking 4(5) 684–706. Salmerón, J., K. Wood, R. Baldick. 2004. Analysis of...electric grid security under terrorist threat. IEEE Transactions on Power Systems 19 905–912. Wood, A. J., B. F. Wollenberg. 1996. Power generation

  19. Optimizing Concurrent M3-Transactions: A Fuzzy Constraint Satisfaction Approach

    Directory of Open Access Journals (Sweden)

    Peng LI

    2004-10-01

    Full Text Available Due to the high connectivity and great convenience, many E-commerce application systems have a high transaction volume. Consequently, the system state changes rapidly and it is likely that customers issue transactions based on out-of-date state information. Thus, the potential of transaction abortion increases greatly. To address this problem, we proposed an M3-transaction model. An M3-transaction is a generalized transaction where users can issue their preferences in a request by specifying multiple criteria and optional data resources simultaneously within one transaction. In this paper, we introduce the transaction grouping and group evaluation techniques. We consider evaluating a group of M3-transactions arrived to the system within a short duration together. The system makes optimal decisions in allocating data to transactions to achieve better customer satisfaction and lower transaction failure rate. We apply the fuzzy constraint satisfaction approach for decision-making. We also conduct experimental studies to evaluate the performance of our approach. The results show that the M3-transaction with group evaluation is more resilient to failure and yields much better performance than the traditional transaction model.

  20. The Econometric Procedures of Specific Transaction Identification

    Directory of Open Access Journals (Sweden)

    Doszyń Mariusz

    2017-06-01

    Full Text Available The paper presents the econometric procedures of identifying specific transactions, in which atypical conditions or attributes may occur. These procedures are based on studentized and predictive residuals of the accordingly specified econometric models. The dependent variable is a unit transactional price, and explanatory variables are both the real properties’ attributes and accordingly defined artificial binary variables. The utility of the proposed method has been verified by means of a real market data base. The proposed procedures can be helpful during the property valuation process, making it possible to reject real properties that are specific (both from the point of view of the transaction conditions and the properties’ attributes and, consequently, to select an appropriate set of similar attributes that are essential for the valuation process.

  1. IEEE 1547 and 2030 Standards for Distributed Energy Resources Interconnection and Interoperability with the Electricity Grid

    Energy Technology Data Exchange (ETDEWEB)

    Basso, T.

    2014-12-01

    Public-private partnerships have been a mainstay of the U.S. Department of Energy and the National Renewable Energy Laboratory (DOE/NREL) approach to research and development. These partnerships also include technology development that enables grid modernization and distributed energy resources (DER) advancement, especially renewable energy systems integration with the grid. Through DOE/NREL and industry support of Institute of Electrical and Electronics Engineers (IEEE) standards development, the IEEE 1547 series of standards has helped shape the way utilities and other businesses have worked together to realize increasing amounts of DER interconnected with the distribution grid. And more recently, the IEEE 2030 series of standards is helping to further realize greater implementation of communications and information technologies that provide interoperability solutions for enhanced integration of DER and loads with the grid. For these standards development partnerships, for approximately $1 of federal funding, industry partnering has contributed $5. In this report, the status update is presented for the American National Standards IEEE 1547 and IEEE 2030 series of standards. A short synopsis of the history of the 1547 standards is first presented, then the current status and future direction of the ongoing standards development activities are discussed.

  2. Implementing e-Transactions with Asynchronous Replication

    OpenAIRE

    Frolund, Svend; Guerraoui, Rachid

    2000-01-01

    An e-Transaction is one that executes exactly-once despite failures. This paper describes a distributed protocol that implements the abstraction of e-Transactionsin three-tier architectures. Three-tier architectures are typically Internet-oriented architectures, where the end-user interacts with front-end clients (e.g., browsers) that invoke middle-tier application servers (e.g., web servers) to access back-end databases. We implement the e-Transaction abstraction using an asynchronous replic...

  3. Plural Governance: A Modified Transaction Cost Model

    DEFF Research Database (Denmark)

    Mols, Niels Peter; Menard, Claude

    2014-01-01

    Plural governance is a form of governance where a firm both makes and buys similar goods or services. Despite a widespread use of plural governance there are no transaction cost models of how plural governance affects performance. This paper reviews the literature about plural forms and proposes...... a model relating transaction cost and resource-based variables to the cost of the plural form. The model is then used to analyze when the plural form is efficient compared to alternative governance structures. We also use the model to discuss the strength of three plural form synergies....

  4. Lazy Evaluation for Concurrent OLTP and Bulk Transactions

    NARCIS (Netherlands)

    Wevers, L.; Huisman, Marieke; van Keulen, Maurice

    2016-01-01

    Existing concurrency control systems cannot execute transactions with overlapping updates concurrently. This is especially problematic for bulk updates, which usually overlap with all concurrent transactions. To solve this, we have developed a concurrency control mechanism based on lazy evaluation,

  5. Heterogeneous cellular networks

    CERN Document Server

    Hu, Rose Qingyang

    2013-01-01

    A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management i

  6. Nonlinear Transaction Pricing in the Securities Trading Value Chain

    OpenAIRE

    Burghardt, Matthias

    2007-01-01

    Most of the research on transaction costs in the market microstructure literature focuses on implicit transaction costs. Research on the design of price schedules for explicit transaction fees is rare. This paper analyzes and classifies different price schedules and discusses their application to the market transaction business. The discussion highlights design issues and the need for a structured approach for price schedule design in the context of market engineering. In order to get some...

  7. Transaction costs and asset prices : a dynamic equilibrium model

    OpenAIRE

    Dimitri Vayanos

    1998-01-01

    In this article we study the effects of transaction costs on asset prices. We assume an overlapping generations economy with a riskless, liquid bond, and many risky stocks carrying proportional transaction costs. We obtain stock prices and turnover in closed form. Surprisingly, a stock's price may increase in transaction costs, and a more frequently traded stock may be less adversely affected by an increase in transaction costs. Calculations based on the 'marginal' investor overestimate the e...

  8. An Extended IEEE 118-Bus Test System With High Renewable Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Pena, Ivonne; Martinez-Anido, Carlo Brancucci; Hodge, Bri-Mathias

    2018-01-01

    This article describes a new publicly available version of the IEEE 118-bus test system, named NREL-118. The database is based on the transmission representation (buses and lines) of the IEEE 118-bus test system, with a reconfigured generation representation using three regions of the US Western Interconnection from the latest Western Electricity Coordination Council (WECC) 2024 Common Case [1]. Time-synchronous hourly load, wind, and solar time series are provided for over one year (8784 hours). The public database presented and described in this manuscript will allow researchers to model a test power system using detailed transmission, generation, load, wind, and solar data. This database includes key additional features that add to the current IEEE 118-bus test model, such as: the inclusion of 10 generation technologies with different heat rate functions, minimum stable levels and ramping rates, GHG emissions rates, regulation and contingency reserves, and hourly time series data for one full year for load, wind and solar generation.

  9. PERFORMANCE STUDY OF DISTRIBUTED COORDINATION FUNCTION OVER IEEE 802.11A PHYSICAL LAYER

    Directory of Open Access Journals (Sweden)

    S. SELVAKENEDDY

    2006-06-01

    Full Text Available IEEE 802.11a is one of the latest standards to be released by the IEEE Project 802 for wireless LANs. It has specified an additional physical layer (PHY to support higher data rates, and is termed as the orthogonal frequency division multiplexing (OFDM. In order to exploit its benefits, one of the medium access control (MAC protocols specified in the IEEE 802.11 specification is called distributed coordination function (DCF. DCF is a carrier sense multiple access with collision avoidance (CSMA/CA scheme with slotted binary exponential backoff. The frames can be transmitted using the basic access scheme or the RTS/CTS scheme in DCF. It was demonstrated previously that the RTS/CTS mechanism works well in most scenarios for the previously specified PHYs. In this work, a simple simulator is developed to verify the scalability of the RTS/CTS mechanism over OFDM PHY, which supports much higher data rates.

  10. An analytical model for the performance analysis of concurrent transmission in IEEE 802.15.4.

    Science.gov (United States)

    Gezer, Cengiz; Zanella, Alberto; Verdone, Roberto

    2014-03-20

    Interference is a serious cause of performance degradation for IEEE802.15.4 devices. The effect of concurrent transmissions in IEEE 802.15.4 has been generally investigated by means of simulation or experimental activities. In this paper, a mathematical framework for the derivation of chip, symbol and packet error probability of a typical IEEE 802.15.4 receiver in the presence of interference is proposed. Both non-coherent and coherent demodulation schemes are considered by our model under the assumption of the absence of thermal noise. Simulation results are also added to assess the validity of the mathematical framework when the effect of thermal noise cannot be neglected. Numerical results show that the proposed analysis is in agreement with the measurement results on the literature under realistic working conditions.

  11. A 1-GHz charge pump PLL frequency synthesizer for IEEE 1394b PHY

    DEFF Research Database (Denmark)

    Ji, J.; Liu, H.; Li, Q.

    2012-01-01

    This paper presents an implementation of multi-rate SerDes transceiver for IEEE 1394b applications. Simple and effective pre-emphasis and equalizer circuits are used at transmitter and receiver, respectively. A phase interpolator based clock and data recovery circuit with optimized linearity...... is also described. With an on-chip fully integrated phase locked loop, the transceiver works at data rates of 100Mb/s, 400Mb/s and 800Mb/s, supporting three different operating modes of S100b, S400b and S800b for IEEE 1394b. The chip has been fabricated using 0.13μm technology. The die area of transceiver...... is 2.9*1.6 mm including bonding pads and the total power dissipation is 284 mW with 1.2V and 3.3V supply voltages. © 2012 IEEE....

  12. 31 CFR 560.526 - Commodities trading and related transactions.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Commodities trading and related transactions. 560.526 Section 560.526 Money and Finance: Treasury Regulations Relating to Money and Finance... Iranian-origin goods, or transactions incidental to such trading, where: (1) No party to the transaction...

  13. Electronic Business Transaction Infrastructure Analysis Using Petri Nets and Simulation

    Science.gov (United States)

    Feller, Andrew Lee

    2010-01-01

    Rapid growth in eBusiness has made industry and commerce increasingly dependent on the hardware and software infrastructure that enables high-volume transaction processing across the Internet. Large transaction volumes at major industrial-firm data centers rely on robust transaction protocols and adequately provisioned hardware capacity to ensure…

  14. 45 CFR 162.1901 - Medicaid pharmacy subrogation transaction.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Medicaid pharmacy subrogation transaction. 162... STANDARDS AND RELATED REQUIREMENTS ADMINISTRATIVE REQUIREMENTS Medicaid Pharmacy Subrogation § 162.1901 Medicaid pharmacy subrogation transaction. The Medicaid pharmacy subrogation transaction is the...

  15. 31 CFR 538.418 - Financial transactions in Sudan.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Financial transactions in Sudan. 538... Interpretations § 538.418 Financial transactions in Sudan. (a) Any financial transaction with a depository institution located in an area of Sudan other than the Specified Areas of Sudan, e.g., Khartoum, remains...

  16. An Architecture for Nested Transaction Support on Standard Database Systems

    NARCIS (Netherlands)

    Boertjes, E.M.; Grefen, P.W.P.J.; Vonk, J.; Apers, Peter M.G.

    Many applications dealing with complex processes require database support for nested transactions. Current commercial database systems lack this kind of support, offering flat, non-nested transactions only. This paper presents a three-layer architecture for implementing nested transaction support on

  17. 17 CFR 31.17 - Records of leverage transactions.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Records of leverage... LEVERAGE TRANSACTIONS § 31.17 Records of leverage transactions. (a) Each leverage transaction merchant receiving a leverage customer's order shall immediately upon receipt thereof prepare a written record of...

  18. 26 CFR 1.446-4 - Hedging transactions.

    Science.gov (United States)

    2010-04-01

    ... sales proceeds. If a hedge is associated with a particular purchase or sales transaction, the gain or... of cost incurred in, or sales proceeds from, that transaction. As with hedges of aggregate risk... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Hedging transactions. 1.446-4 Section 1.446-4...

  19. 19 CFR 4.90 - Simultaneous vessel transactions.

    Science.gov (United States)

    2010-04-01

    ... transactions. (a) A vessel may proceed from port to port in the United States for the purpose of engaging in two or more of the following transactions simultaneously, 121 subject to the limitations hereafter... 19 Customs Duties 1 2010-04-01 2010-04-01 false Simultaneous vessel transactions. 4.90 Section 4...

  20. 17 CFR 300.503 - Voidable securities transactions.

    Science.gov (United States)

    2010-04-01

    ... proceeding under the Act to avoid any securities transaction as fraudulent, preferential, or otherwise... securities transaction which could have been avoided in a liquidation proceeding under the Act. ... transactions. 300.503 Section 300.503 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION...

  1. 12 CFR 563.41 - Transactions with affiliates.

    Science.gov (United States)

    2010-01-01

    ... its affiliates and any other person to the extent that the proceeds of a transaction are used for the... proceed with the proposed transaction. ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Transactions with affiliates. 563.41 Section...

  2. Design of a of a survivable multi-wavelength photonic access network

    NARCIS (Netherlands)

    Roy, R.; van Etten, Wim

    2007-01-01

    This paper investigates the design of protection schemes in an extended access network. The network is modeled as a stack of quasi independent logical passive optical networks(PONs), each operating the IEEE Ethernet passive optical networks (EPON) protocol. The dynamics of the network operation when

  3. Design of acquisition devices management subsystem for IEEE 1073 compliant software agents.

    Science.gov (United States)

    Nagin, V A; Potapov, I V; Selishchev, S V

    2002-01-01

    The paper addresses the issue of device management system design for software agents compliant with IEEE 1073 device communication standard. Based on middleware architecture the device control layer represents a universal versatile object-oriented application-programming interface. The approach presented in the paper allows to implement plug-and-play integration and interoperability of medical acquisition devices within the medical device system be means of common middleware services. Adherence to Medical Data Information Base nomenclature, component part of IEEE 1073 communication standard, adds necessary consistency to presented component-based infrastructure.

  4. BER Analysis Of IEEE802.11n MIMO System Using MMSE And ZF Detectors

    Directory of Open Access Journals (Sweden)

    Ye Lwin Oo

    2015-06-01

    Full Text Available Abstract With the increasing demand of higher data rate for telecommunication the IEEE802.11n standard was constituted in 2009. The most important character of the standard is MIMO-OFDM which not only improves the throughput but also the spectrum efficiency and channel capacity. And in wireless communication the role of MIMO detectors plays an important part to remove inter-symbol interference ISI caused by multipath fading channel. In this paper the BER performance of IEEE 802.11n for 3x2 4x2 and 4x3 antennas are compared using MMSE and ZF detectors in Matlab Simulink.

  5. Reactive GTS Allocation Protocol for Sporadic Events Using the IEEE 802.15.4

    Directory of Open Access Journals (Sweden)

    Mukhtar Azeem

    2014-01-01

    by the IEEE 802.15.4 standard. The proposed control protocol ensures that a given offline sporadic schedule can be adapted online in a timely manner such that the static periodic schedule has not been disturbed and the IEEE 802.15.4 standard compliance remains intact. The proposed protocol is simulated in OPNET. The simulation results are analyzed and presented in this paper to prove the correctness of the proposed protocol regarding the efficient real-time sporadic event delivery along with the periodic event propagation.

  6. Analysis Of Impact Of Various Parameters On BER Performance For IEEE 802.11b

    Directory of Open Access Journals (Sweden)

    Nilesh B. Kalani

    2015-08-01

    Full Text Available Abstract This paper discusses about IEEE 802.11b simulation model implemented using LabVIEW software and its analyses for impact on bit error rate BER for different parameters as channel type channel number data transmission rate and packet size. Audio file is being transmitted processed and analyzed using the model for various parameters. This paper gives analysis of BER verses ESN0 for various parameter like data rate packet size and communication channel for the IEEE 802.11b simulation model generated using LabVIEW. It is proved that BER can be optimized by tweaking different parameters of wireless communication system.

  7. International Conference on Grey Systems and intelligent Services (IEEE GSIS 2009)

    CERN Document Server

    Liu, Sifeng; Advances in Grey Systems Research

    2010-01-01

    This book contains contributions by some of the leading researchers in the area of grey systems theory and applications. All the papers included in this volume are selected from the contributions physically presented at the 2009 IEEE International Conference on Grey Systems and Intelligent Services, November 11 – 12, 2009, Nanjing, Jiangsu, People’s Republic of China. This event was jointly sponsored by IEEE Systems, Man, and Cybernetics Society, Natural Science Foundation of China, and Grey Systems Society of China. Additionally, Nanjing University of Aeronautics and Astronautics also invested heavily in this event with its direct and indirect financial and administrative supports.

  8. Optimal Power Flow Analysis of IEEE 14 System with Distributed Generators

    Directory of Open Access Journals (Sweden)

    DULĂU Lucian Ioan

    2016-05-01

    Full Text Available This paper describes the mathematical model for the optimal power flow analysis of the IEEE 14 bus system. In the IEEE 14 bus system were connected two distributed generators (DGs: a hydro generator and a photovoltaic power plant. The two objective functions which are minimized, are the generation costs and the total power losses of the system, while there are satisfied equality and inequality constraints. The optimal power flow analysis will be performed for the steady-state condition of the system and for the whole day, for two cases: the DGs are connected to the system and the DGs are not connected to the system.

  9. Protocolo de pruebas para máquinas rotativas de baja potencia fundamentadas en Normas IEEE

    OpenAIRE

    Ochoa Gutiérrez, Paúl Santiago

    2012-01-01

    En esta guía se ha realizado un análisis técnico para lograr normalizar la ejecución de los ensayos en los laboratorios de máquinas eléctricas, listar los equipos y procedimientos para la valoración de las pruebas, siguiendo lineamientos establecidos en las normativas IEEE 112-1996, 115-1995, 113-1985. El documento sintetiza: el tipo de pruebas; la selección de las pruebas; el uso de las normas IEEE; las pruebas con carga; la prueba de rotor bloqueado; y la hoja de toma de datos. Valida...

  10. Beyond Intra-Transaction Association Analysis: Mining Multi-Dimensional Inter-Transaction Association Rules

    NARCIS (Netherlands)

    Lu, H.J.; Feng, L.; Han, J.W.

    2000-01-01

    In this paper, we extend the scope of mining association rules from traditional single-dimensional intratransaction associations, to multidimensional intertransaction associations. Intratransaction associations are the associations among items with the same transaction, where the notion of the

  11. Relationship between transactional leadership and knowledge ...

    African Journals Online (AJOL)

    The Transactional style of leadership involves motivating and directing followers primarily through appealing to their own self-interest. Besides, Knowledge management (KM) is the process of capturing, developing, sharing, and effectively using organizational knowledge. It refers to a multi-disciplined approach to achieving ...

  12. Trust management for e-transactions

    Indian Academy of Sciences (India)

    Transactions and services over the internet have global reach and users, known or unknown to the service provider, might be interested in availing access or participating ... Trust plays a crucial role in the design of optimal contracts; not all the relevant, valuable information on the user's choice of action is incorporated in the ...

  13. Economic transactions, opportunistic behavior and protective mechanisms

    DEFF Research Database (Denmark)

    Koch, Carsten Allan

    Whenever actors participate in transactions they expose themselves to risks of various kinds. Some of these risks are attributable to events outside the control of the participants and are unavoidable. Others originate in, or are aggrevated by, opportunistic actions undertaken by contract partner...

  14. Rethinking Ethiopian Secured Transactions Law through ...

    African Journals Online (AJOL)

    Asress Adimi Gikay

    September 2017. Introduction. International organizations and states recognize modern secured transactions law as vital for economic development. The United Nations Commission on. International Trade Law (UNCITRAL),2. EBRD3 and the Institute for. Unification of Private International Law (UNIDROIT) are among the ...

  15. A Transactional Model of Bullying and Victimization

    Science.gov (United States)

    Georgiou, Stelios N.; Fanti, Kostas A.

    2010-01-01

    The purpose of the current study was to develop and test a transactional model, based on longitudinal data, capable to describe the existing interrelation between maternal behavior and child bullying and victimization experiences over time. The results confirmed the existence of such a model for bullying, but not for victimization in terms of…

  16. 75 FR 48562 - Iranian Transactions Regulations

    Science.gov (United States)

    2010-08-11

    ... transactions with respect to the development of Iranian petroleum resources. On May 6, 1995, to further respond... ENGINEERING COMPANY (a.k.a. MAHAB GHODSS CONSULTING ENGINEERING CO.; a.k.a. MAHAB GHODSS CONSULTING ENGINEERS SSK; a.k.a. MAHAB QODS ENGINEERING CONSULTING CO.), 16 Takharestan Alley, Dastgerdy Avenue, P.O. Box...

  17. Towards Online and Transactional Relational Schema Transformations

    NARCIS (Netherlands)

    Wevers, L.; Hofstra, Matthijs; Tammens, Menno; Huisman, Marieke; van Keulen, Maurice

    2014-01-01

    In this paper, we want to draw the attention of the database community to the problem of online schema changes: changing the schema of a database without blocking concurrent transactions. We have identified important classes of relational schema transformations that we want to perform online, and we

  18. Foreign experience of regulating international trade transactions

    Directory of Open Access Journals (Sweden)

    Klymenko L. V.

    2015-05-01

    Full Text Available The article deals with the international experience of state regulating international trade transactions; nature, directions and contradictions of contemporary processes of globalization are defined; components of regulatory and incentive means in system of state supporting foreign trade activity of commodity producers are considered; general provisions for the improvement of state regulation mechanisms of export-import activities in Ukraine are determined.

  19. Trust management for e-transactions

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Transactions and services over the internet have global reach and users, known or unknown to the ... medium for disseminating information, doing commerce and business. The enabling tech- nologies are .... centralized models like X.509, trust accumulates at the global CA (root certification authority) and trustworthiness of ...

  20. Transformational and transactional leadership styles among leaders ...

    African Journals Online (AJOL)

    In contrast to transformational leadership where the leader works with employees to identify the needed change, creating a vision to guide the change through inspiration, and executing the change in tandem with committed members of the group, transactional leadership styles focus on the use of rewards and punishments ...

  1. Transactions of the Zimbabwe Scientific Association

    African Journals Online (AJOL)

    The Zimbabwe Scientific Association was founded in Bulawayo in 1899 (called the Rhodesia Scientific Assocation at the time) to promote the study and advancement of science in Zimbabwe and to facilitate the acquisition and dissemination of scientific knowledge. Its journal, Transactions of the Zimbabwe Scientific ...

  2. 17 CFR 30.3 - Prohibited transactions.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Prohibited transactions. 30.3 Section 30.3 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION FOREIGN FUTURES AND... foreign board of trade, and carried for or on behalf of a customer at a designated contract market...

  3. 31 CFR 800.207 - Covered transaction.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Covered transaction. 800.207 Section 800.207 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF INVESTMENT SECURITY, DEPARTMENT OF THE TREASURY REGULATIONS PERTAINING TO MERGERS, ACQUISITIONS, AND...

  4. Gestion des transactions en environnement mobile | Nouali ...

    African Journals Online (AJOL)

    Management of Transactions In Mobile Computing Environment Increasingly diverse applications have made computers an ubiquitous part of our daily lives. As their range of applications widens, demand is growing for computers that can perform outside the home or office. Accordingly, mobile computing is attracting ...

  5. 31 CFR 537.210 - Exempt transactions.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Exempt transactions. 537.210 Section 537.210 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF... personal and household effects set forth in §§ 537.511 and 537.514. ...

  6. Private benefits in corporate control transactions

    DEFF Research Database (Denmark)

    Poulsen, Thomas

    This paper presents an analytical framework from which it can be inferred whether sellers or buyers in corporate control transactions value private benefits highest. I am thus able to suggest an answer to the question: Are blocks of shares traded because the buyer is a more efficient monitor...

  7. Private Benefits in Corporate Control Transactions

    DEFF Research Database (Denmark)

    Poulsen, Thomas

    2011-01-01

    This paper presents an analytical framework from which it can be inferred whether sellers or buyers in block transactions value private benefits highest. I am thus able to suggest an answer to the question: Are blocks of shares traded because the buyer has high security benefits, or because the b...

  8. 76 FR 41375 - Retail Foreign Exchange Transactions

    Science.gov (United States)

    2011-07-14

    ... Commodity Futures Trading Commission (CFTC) issued a retail forex rule for persons subject to its... trading strategies; or (iii) the customer employs different trading strategies in one account and applies... transactions is trading as principal, by definition, when the retail forex customer loses money on a retail...

  9. 77 FR 62177 - Retail Foreign Exchange Transactions

    Science.gov (United States)

    2012-10-12

    ... (CFTC) with jurisdiction over certain accounts and pooled investment vehicles trading in retail forex, a...' forex trading is with bank funds or insurance company separate accounts? Question 5. Should the OCC's... \\5\\ (a retail foreign exchange (forex) rule). Transactions described in section 2(c)(2)(B)(i)(I...

  10. 76 FR 56094 - Retail Foreign Exchange Transactions

    Science.gov (United States)

    2011-09-12

    ... section is as follows: Risk Disclosure Statement Retail forex transactions involve the leveraged trading... margin for retail forex trading. You may lose more than you pledge as margin. If your margin falls below... before determining whether retail forex trading is appropriate for you. (1) Trading is not on a regulated...

  11. Culture and subculture in transactional letter writing

    DEFF Research Database (Denmark)

    Shaw, Philip; Okamura, Akiko

    2000-01-01

    This study examines the relative contributions of subculture membership and mother-tongue status/target culture membership in writing transactional letters. We examined the letters accompanying articles initially submitted for publication by 26 NSE and 23 NNSE academics, and compared them...

  12. Related party transactions and firms financial performance ...

    African Journals Online (AJOL)

    The study investigated related party transactions and firm's financial performance using Secondary data obtained from Nigeria stock Exchange. We tried to determine whether RPT is used by firms to manipulate and bloat Return on Asset, Return on Equity and Earnings per share of manufacturing firms. RPT was subjected ...

  13. Investment in electricity networks with transmission switching

    DEFF Research Database (Denmark)

    Villumsen, Jonas Christoffer; Philpott, A.B.

    2012-01-01

    allows the solution of large problem instances. The methodology is illustrated by its application to a problem of determining the optimal investment in switching equipment and transmission capacity for an existing network. Computational tests on IEEE test networks with 73 nodes and 118 nodes confirm...

  14. Wireless Networks: New Meaning to Ubiquitous Computing.

    Science.gov (United States)

    Drew, Wilfred, Jr.

    2003-01-01

    Discusses the use of wireless technology in academic libraries. Topics include wireless networks; standards (IEEE 802.11); wired versus wireless; why libraries implement wireless technology; wireless local area networks (WLANs); WLAN security; examples of wireless use at Indiana State University and Morrisville College (New York); and useful…

  15. DAWN: Dynamic Ad-hoc Wireless Network

    Science.gov (United States)

    2016-06-19

    Wireless Network 1 Introduction The network-centric battlefield includes sensors, troop carriers, unmanned air vehicle (UAV), aircraft, smart ...Bellman Control Heritage Award. • Honorary Doctorate at Technical University of Crete. • Best paper award at 2008 IEEE International Conference on Mobile Ad-hoc and Sensor Systems.

  16. 17 CFR 242.601 - Dissemination of transaction reports and last sale data with respect to transactions in NMS stocks.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Dissemination of transaction reports and last sale data with respect to transactions in NMS stocks. 242.601 Section 242.601 Commodity... National Market System § 242.601 Dissemination of transaction reports and last sale data with respect to...

  17. Transactive Campus Energy Systems: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Katipamula, Srinivas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Corbin, Charles D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Haack, Jereme N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hao, He [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Woohyun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hostick, Donna J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Akyol, Bora A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Allwardt, Craig H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carpenter, Brandon J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Huang, Sen [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Liu, Guopeng [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lutes, Robert G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Makhmalbaf, Atefe [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mendon, Vrushali V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ngo, Hung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Somasundaram, Sriram [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Underhill, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhao, Mingjie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-09-26

    Transactive energy refers to the combination of economic and control techniques to improve grid reliability and efficiency. The fundamental purpose of transactive energy management is to seamlessly coordinate the operation of large numbers of new intelligent assets—such as distributed solar, energy storage and responsive building loads—to provide the flexibility needed to operate the power grid reliably and at minimum cost, particularly one filled with intermittent renewable generation such as the Pacific Northwest. It addresses the key challenge of providing smooth, stable, and predictable “control” of these assets, despite the fact that most are neither owned nor directly controlled by the power grid. The Clean Energy and Transactive Campus (CETC) work described in this report was done as part of a Cooperative Research and Development Agreement (CRADA) between the U.S. Department of Energy’s Pacific Northwest National Laboratory (PNNL) and the Washington State Department of Commerce (Commerce) through the Clean Energy Fund (CEF). The project team consisted of PNNL, the University of Washington (UW) and Washington State University (WSU), to connect the PNNL, UW, and WSU campuses to form a multi-campus testbed for transaction-based energy management—transactive—solutions. Building on the foundational transactive system established by the Pacific Northwest Smart Grid Demonstration (PNWSGD), the purpose of the project was to construct the testbed as both a regional flexibility resource and as a platform for research and development (R&D) on buildings/grid integration and information-based energy efficiency. This report provides a summary of the various tasks performed under the CRADA.

  18. Would Ronald Coase love Bitcoin? How Blockchain Lowers Transaction Costs and Changes the Coasian Firm

    OpenAIRE

    Kaid, Amira

    2017-01-01

    The rising popularity of blockchain technology otherwise known as the technology that underlies the Bitcoin protocol has been the subject of a lot of investigation and enthusiasm among financial organizations for its potentially revolutionary properties that will likely change how the economy works in the future. The blockchain is a decentralized open source ledger that records bitcoin transactions and is maintained by a distributed network of miners. Blockchain technology however has many ap...

  19. Transaction-Based Building Controls Framework, Volume 1: Reference Guide

    Energy Technology Data Exchange (ETDEWEB)

    Somasundaram, Sriram [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pratt, Robert G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Akyol, Bora A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fernandez, Nicholas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Foster, Nikolas AF [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Katipamula, Srinivas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mayhorn, Ebony T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Somani, Abhishek [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Steckley, Andrew C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Taylor, Zachary T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-12-01

    This document proposes a framework concept to achieve the objectives of raising buildings’ efficiency and energy savings potential benefitting building owners and operators. We call it a transaction-based framework, wherein mutually-beneficial and cost-effective market-based transactions can be enabled between multiple players across different domains. Transaction-based building controls are one part of the transactional energy framework. While these controls realize benefits by enabling automatic, market-based intra-building efficiency optimizations, the transactional energy framework provides similar benefits using the same market -based structure, yet on a larger scale and beyond just buildings, to the society at large.

  20. How to deal with malleability of BitCoin transactions

    OpenAIRE

    Andrychowicz, Marcin; Dziembowski, Stefan; Malinowski, Daniel; Mazurek, Łukasz

    2013-01-01

    BitCoin transactions are malleable in a sense that given a transaction an adversary can easily construct an equivalent transaction which has a different hash. This can pose a serious problem in some BitCoin distributed contracts in which changing a transaction's hash may result in the protocol disruption and a financial loss. The problem mostly concerns protocols, which use a "refund" transaction to withdraw a deposit in a case of the protocol interruption. In this short note, we show a gener...

  1. ASSESSING BUSINESS TRANSACTION STANDARDS AND THEIR ADOPTION A cross case analysis between the SETU and Vektis standards

    NARCIS (Netherlands)

    Berends, Wouter; Folmer, Erwin Johan Albert

    2010-01-01

    Nowadays businesses increasingly want to be interoperable so that they can collaborate with other organizations. Interoperability can be achieved through the use of business transaction standards, by which the organizations that use the standards collectively form a value added network. However the

  2. Fresh Snack Food Channel Evaluation Model for Integrating Customers’ Perception of Transaction Costs in Taiwan

    Directory of Open Access Journals (Sweden)

    Po-Yu Chen

    2017-01-01

    Full Text Available The primary purpose of this study was to explore how food dealers develop methods that facilitate transaction efficiency and how they select the optimal food channels. This study establishes a model according to the impact of transaction cost factors on consumers’ decision-making regarding purchase of fresh snack foods. Using fresh snack foods in Taiwan as an example, this study employed a fuzzy analytic network process to solve decision-making problems with multiple criteria by comparing the interaction between each transaction cost factor to obtain the factor weightings as well as the weightings of the transaction costs at each decision stage. This study found that food safety assurance and providing sufficient nutrition information were the most essential topics; thus, the optimal choice for snack food producers is to develop retail outlets. This study construction process proposed is innovative and operational, and the results may provide a reference for snack food dealers or microfood enterprises to assist them in developing their food channels.

  3. Market Model Considering Bilateral Transactions in the Deregulated Electricity Market

    Science.gov (United States)

    Ruiz Monroy, José Joaquín; Kita, Hiroyuki; Tanaka, Eiichi; Hasegawa, Jun

    This paper proposes an algorithm to simulate the transactions that take place in a free market of electricity. The algorithm presented is used for Bilateral Transaction Matrix (BTM) creation assuming that a day ahead load forecast is previously known. Bids can be made by both the generation side and the demand side to determine transaction prices, then the algorithm allocates the transactions according to market rules until the demand is satisfied. This creates feasible BTMs that can be used to study system security and to find future methods to regulate bilateral transactions through market mechanisms like the application of penalties to the transactions that affect the system’s security. Results show that the proposed algorithm is a good option for electricity market analysis. The proposed algorithm provides system planners with a practical tool for data creation to further study the effects of bilateral transactions in a deregulated electricity market.

  4. IEEE Computer Society/Software Engineering Institute Watts S. Humphrey Software Process Achievement (SPA) Award 2016: Nationwide

    Science.gov (United States)

    2017-04-05

    REV-03.18.2016.0 IEEE Computer Society/Software Engineering Institute Watts S. Humphrey Software Process Achievement (SPA) Award 2016...20503. 1. AGENCY USE ONLY (Leave Blank) 2. REPORT DATE April 2017 3. REPORT TYPE AND DATES COVERED Final 4. TITLE AND SUBTITLE IEEE Computer

  5. Application of radial basis neural network for state estimation of ...

    African Journals Online (AJOL)

    user

    An original application of radial basis function (RBF) neural network for power system state estimation is proposed in this paper. The property of massive parallelism of neural networks is employed for this. The application of RBF neural network for state estimation is investigated by testing its applicability on a IEEE 14 bus ...

  6. Evaluation of QoS Provisioning Capabilities of IEEE 802.11E Wireless LANs

    NARCIS (Netherlands)

    Roijers, Frank; van den Berg, Hans Leo; Fan, Xiang; Fleuren, Maria; Braun, Torsten; Carle, Georg; Koucheryavy, Yevgeni; Tsaoussidis, Vassilis

    2005-01-01

    Several studies in literature have investigated the performance of the proposed ieee 802.11e standard for qos differentiation in wlan, but most of them are limited both with respect to the range of the parameter settings and the considered traffic scenarios.The aim of the present study is to

  7. 0011-0030.Content Alerts in IEEE XploreLearn.pdf | 01 | 021 | reso ...

    Indian Academy of Sciences (India)

    Home; public; Volumes; reso; 021; 01; 0011-0030.Content Alerts in IEEE XploreLearn.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Summer Research Fellowship Programme 2018 ...

  8. 0011-0030.IEEE 754: 64 Bit Double Precision FloatsThis.pdf | 01 ...

    Indian Academy of Sciences (India)

    Home; public; Volumes; reso; 021; 01; 0011-0030.IEEE 754: 64 Bit Double Precision FloatsThis.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Good Governance: Contribution of ...

  9. 0011-0030.Eng Hussein Mohammad Al-Masri Pres at 2015 IEEE ...

    Indian Academy of Sciences (India)

    Masri Pres at 2015 IEEE IAS Conference in DallasUSAIEEE ULT SB IAS participationWe.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog ...

  10. 0011-0030.IEEE Floating Point Addition amp MultiplicationPlease ...

    Indian Academy of Sciences (India)

    Home; public; Volumes; reso; 021; 01; 0011-0030.IEEE Floating Point Addition amp MultiplicationPlease.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube · Twitter · Facebook · Blog. Academy News. IAS Logo. Live streaming of the Symposium ...

  11. Computer Controlled Test Systems. Introduction. A Course Based on the IEEE 488 Bus.

    Science.gov (United States)

    Herrmann, Eric J.

    An introductory course in computer automated tests and measurement systems based on the International Test Instrument-Computer Interface Standard, the IEEE (Institute of Electrical and Electronics Engineers)-488, is presented in this study guide. This course is designed to: (1) introduce the electronics engineering technician to the functional…

  12. Incorporating antenna beamswitching technique into drivers for IEEE802.11 WLAN devices

    CSIR Research Space (South Africa)

    Mofolo, M

    2015-11-23

    Full Text Available the beamswitching technique for switched parasitic array (SPA) and electronically steerable parasitic array radiator (ESPAR) antennas in the drivers for IEEE802.11 WLAN devices. The modifications of the open source drivers (ath5k and ath9k) to enable real...

  13. Synchronization Analysis and Simulation of a Standard IEEE 802.11G OFDM Signal

    Science.gov (United States)

    2004-03-01

    on Vehicular Technology, Vol. 48, No. 5, pp.1596- 1609, September 1999. 19. Flavio Daffara and Antoine Chouly, “Maximum Likelihood Frequency...November 1996. 21. Flavio Daffara and Ottavio Adami, “A New Frequency Detector for Orthogonal Multicarrier Transmission Techniques,” Proc. of IEEE

  14. Fault-Tolerant Topology and Routing Synthesis for IEEE Time-Sensitive Networking

    DEFF Research Database (Denmark)

    Gavrilut, Voica Maria; Zarrin, Bahram; Pop, Paul

    2017-01-01

    of the applications are satisffied. We propose three approaches to solve this optimization problem: (1) a heuristic solution, (2) a Greedy Randomized Adaptive Search Procedure (GRASP) metaheuristic, and (3) a Constraint Programmingbased model. The approaches are evaluated on several test cases, including a test case...

  15. IEEE 802.11ac sebagai Standar Pertama untuk Gigabit Wireless LAN

    Directory of Open Access Journals (Sweden)

    Afdhal Afdhal

    2014-04-01

    Full Text Available WLAN is a technology that currently has been used widely. This technology is considered as a data transferring media technology within the LAN/MAN. To ensure that WLAN technology can be used widely in the whole world, the IEEE has set a standard known as 802.11 to be an international standard for the WLAN technology. This standard was appeared in 1997, and has been revised and improved for several times. This improvement is done to anticipate the rapidly grown WLAN market as well as to keep this technology remains effective, efficient, and reliable at any time. At the beginning of 2014, the IEEE has set 802.11ac-2013 as a new standard for WLANs that operate below 6 GHz to achieve a data rate for up to 7 Gbps. The purpose of this article is to describe comprehensively the IEEE 802.11ac standard as a result of recent changes to the regulatory for WLAN technology which is known as the first standard issued by the IEEE for the gigabit WLANs. This article discusses the goals and objectives to be achieved by 802.11ac standard as well as the parts that have been enhanced significantly both in its PHY and MAC layers. This article will also contrast the differences between the 802.11ac standard and previous WLAN standards. Finally it will also explain the level of compatibility and interoperability of 802.11ac standards with some of previous WLAN standard.Keywords: IEEE, 802.11, 802.11ac, Gigabit WLAN

  16. Achievable capacity limit of high performance nodes for wireless mesh networks

    CSIR Research Space (South Africa)

    Olwal, T

    2012-08-01

    Full Text Available have the ability to simultaneously communicate with many neighbours using multiple radios over orthogonal channels thereby improving effective and "online" channel utilisation. Many such networks emerging from standards such as IEEE 802.11 a...

  17. Transactive Control of Commercial Building HVAC Systems

    Energy Technology Data Exchange (ETDEWEB)

    Corbin, Charles D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Makhmalbaf, Atefe [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Huang, Sen [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mendon, Vrushali V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhao, Mingjie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Somasundaram, Sriram [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Liu, Guopeng [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ngo, Hung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Katipamula, Srinivas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-12-30

    This document details the development and testing of market-based transactive controls for building heating, ventilating and air conditioning (HVAC) systems. These controls are intended to serve the purposes of reducing electricity use through conservation, reducing peak building electric demand, and providing demand flexibility to assist with power system operations. This report is the summary of the first year of work conducted under Phase 1 of the Clean Energy and Transactive Campus Project. The methods and techniques described here were first investigated in simulation, and then subsequently deployed to a physical testbed on the Pacific Northwest National Laboratory (PNNL) campus for validation. In this report, we describe the models and control algorithms we have developed, testing of the control algorithms in simulation, and deployment to a physical testbed. Results from physical experiments support previous simulation findings, and provide insights for further improvement.

  18. Transactional distance in a blended learning environment

    Directory of Open Access Journals (Sweden)

    Jon Dron

    2004-12-01

    Full Text Available This paper presents a case study that describes and discusses the problems encountered during the design and implementation of a blended learning course, largely taught online through a web-based learning environment. Based on Moore's theory of transactional distance, the course was explicitly designed to have dialogue at its heart. However, the reality of systemic behaviours caused by delivering such a course within a group of conventional further and higher educational institutions has led to an entirely unanticipated reversion to structure, with unpleasant consequences for both quality and quantity of dialogue. The paper looks at some of the reasons for this drift, and suggests that some of the disappointing results (in particular in terms of the quality of the students' experience and associated poor retention can be attributed to the lack of dialogue, and consequent increase in transactional distance. It concludes with a description and evaluation of steps currently being taken to correct this behaviour.

  19. The quantum handshake entanglement, nonlocality and transactions

    CERN Document Server

    Cramer, John G

    2016-01-01

    This book shines bright light into the dim recesses of quantum theory, where the mysteries of entanglement, nonlocality, and wave collapse have motivated some to conjure up multiple universes, and others to adopt a "shut up and calculate" mentality. After an extensive and accessible introduction to quantum mechanics and its history, the author turns attention to his transactional model. Using a quantum handshake between normal and time-reversed waves, this model provides a clear visual picture explaining the baffling experimental results that flow daily from the quantum physics laboratories of the world. To demonstrate its powerful simplicity, the transactional model is applied to a collection of counter-intuitive experiments and conceptual problems.

  20. Distributed Energy Systems Integration and Demand Optimization for Autonomous Operations and Electric Grid Transactions

    Energy Technology Data Exchange (ETDEWEB)

    Ghatikar, Girish [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Greenlots, San Francisco, CA (United States); Mashayekh, Salman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stadler, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Center for Energy and Innovation Technologies (Austria); Yin, Rongxin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liu, Zhenhua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-11-29

    Distributed power systems in the U.S. and globally are evolving to provide reliable and clean energy to consumers. In California, existing regulations require significant increases in renewable generation, as well as identification of customer-side distributed energy resources (DER) controls, communication technologies, and standards for interconnection with the electric grid systems. As DER deployment expands, customer-side DER control and optimization will be critical for system flexibility and demand response (DR) participation, which improves the economic viability of DER systems. Current DER systems integration and communication challenges include leveraging the existing DER and DR technology and systems infrastructure, and enabling optimized cost, energy and carbon choices for customers to deploy interoperable grid transactions and renewable energy systems at scale. Our paper presents a cost-effective solution to these challenges by exploring communication technologies and information models for DER system integration and interoperability. This system uses open standards and optimization models for resource planning based on dynamic-pricing notifications and autonomous operations within various domains of the smart grid energy system. It identifies architectures and customer engagement strategies in dynamic DR pricing transactions to generate feedback information models for load flexibility, load profiles, and participation schedules. The models are tested at a real site in California—Fort Hunter Liggett (FHL). Furthermore, our results for FHL show that the model fits within the existing and new DR business models and networked systems for transactive energy concepts. Integrated energy systems, communication networks, and modeling tools that coordinate supply-side networks and DER will enable electric grid system operators to use DER for grid transactions in an integrated system.