WorldWideScience

Sample records for cooperative base stations

  1. Cooperative Proxy Caching for Wireless Base Stations

    Directory of Open Access Journals (Sweden)

    James Z. Wang

    2007-01-01

    Full Text Available This paper proposes a mobile cache model to facilitate the cooperative proxy caching in wireless base stations. This mobile cache model uses a network cache line to record the caching state information about a web document for effective data search and cache space management. Based on the proposed mobile cache model, a P2P cooperative proxy caching scheme is proposed to use a self-configured and self-managed virtual proxy graph (VPG, independent of the underlying wireless network structure and adaptive to the network and geographic environment changes, to achieve efficient data search, data cache and date replication. Based on demand, the aggregate effect of data caching, searching and replicating actions by individual proxy servers automatically migrates the cached web documents closer to the interested clients. In addition, a cache line migration (CLM strategy is proposed to flow and replicate the heads of network cache lines of web documents associated with a moving mobile host to the new base station during the mobile host handoff. These replicated cache line heads provide direct links to the cached web documents accessed by the moving mobile hosts in the previous base station, thus improving the mobile web caching performance. Performance studies have shown that the proposed P2P cooperative proxy caching schemes significantly outperform existing caching schemes.

  2. Impact of Base Station Cooperation on Cell Planning

    Directory of Open Access Journals (Sweden)

    Ian Dexter Garcia

    2010-01-01

    Full Text Available Base station cooperation (BSC has been identified as a key radio access technology for next-generation cellular networks such as LTE-Advanced. BSC impacts cell planning, which is the methodical selection of base station (BS sites, and BS equipment configuration for cost-effective cellular networks. In this paper, the impact of BSC on cell plan parameters (coverage, traffic, handover, and cost, as well as additional cell planning steps required for BSC are discussed. Results show that BSC maximizes its gains over noncooperation (NC in a network wherein interference from cooperating BSs is the main limitation. Locations exist where NC may produce higher throughputs, therefore dynamic or semistatic switching between BSC and NC, called fractional BSC, is recommended. Because of interference from noncooperating BSs, the gains of BSC over NC are upper bounded, and diminishes at greater intersite distances because of noise. This encourages smaller cell sizes, higher transmit powers, and dynamic clustering of cooperative BSs.

  3. Analysis of Synchronization Impairments for Cooperative Base Stations Using OFDM

    Directory of Open Access Journals (Sweden)

    Konstantinos Manolakis

    2015-01-01

    Full Text Available Base station cooperation is envisioned as a key technology for future cellular networks, as it has the potential to eliminate intercell interference and to enhance spectral efficiency. To date, there is still lack of understanding of how imperfect carrier and sampling frequency synchronization between transmitters and receivers limit the potential gains and what the actual system requirements are. In this paper, OFDM signal model is established for multiuser multicellular networks, describing the joint effect of multiple carrier and sampling frequency offsets. It is shown that the impact of sampling offsets is much smaller than the impact of carrier frequency offsets. The model is extended to the downlink of base-coordinated networks and closed-form expressions are derived for the mean power of users’ self-signal, interuser, and intercarrier interference, whereas it is shown that interuser interference is the main source of degradation. The SIR is inverse to the base stations’ carrier frequency variance and to the square of time since the last precoder update, whereas it grows with the number of base stations and drops with the number of users. Through user selection, the derived SIR upper bound can be approached. Finally, system design recommendations for meeting synchronization requirements are provided.

  4. Cooperative Station History Forms

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Various forms, photographs and correspondence documenting the history of Cooperative station instrumentation, location changes, inspections, and...

  5. On a User-Centric Base Station Cooperation Scheme for Reliable Communications

    DEFF Research Database (Denmark)

    Kim, Dong Min; Thomsen, Henning; Popovski, Petar

    2017-01-01

    In this paper, we describe CoMP2flex, a user-centric base station (BS) cooperation scheme that provides improvements in reliability of both uplink (UL) and downlink (DL) communications of wireless cellular networks. CoMP2flex supports not only cooperation of two BSs with same direction of traffic...

  6. Throughput of Cellular Systems with Conferencing Mobiles and Cooperative Base Stations

    Directory of Open Access Journals (Sweden)

    Somekh O

    2008-01-01

    Full Text Available This paper considers an enhancement to multicell processing for the uplink of a cellular system, whereby the mobile stations are allowed to exchange messages on orthogonal channels of fixed capacity (conferencing. Both conferencing among mobile stations in different cells and in the same cell (inter- and intracell conferencing, resp. are studied. For both cases, it is shown that a rate-splitting transmission strategy, where part of the message is exchanged on the conferencing channels and then transmitted cooperatively to the base stations, is capacity achieving for sufficiently large conferencing capacity. In case of intercell conferencing, this strategy performs convolutional pre-equalization of the signal encoding the common messages in the spatial domain, where the number of taps of the finite-impulse response equalizer depends on the number of conferencing rounds. Analysis in the low signal-to-noise ratio regime and numerical results validate the advantages of conferencing as a complementary technology to multicell processing.

  7. Throughput of Cellular Systems with Conferencing Mobiles and Cooperative Base Stations

    Directory of Open Access Journals (Sweden)

    S. Shamai (Shitz

    2008-05-01

    Full Text Available This paper considers an enhancement to multicell processing for the uplink of a cellular system, whereby the mobile stations are allowed to exchange messages on orthogonal channels of fixed capacity (conferencing. Both conferencing among mobile stations in different cells and in the same cell (inter- and intracell conferencing, resp. are studied. For both cases, it is shown that a rate-splitting transmission strategy, where part of the message is exchanged on the conferencing channels and then transmitted cooperatively to the base stations, is capacity achieving for sufficiently large conferencing capacity. In case of intercell conferencing, this strategy performs convolutional pre-equalization of the signal encoding the common messages in the spatial domain, where the number of taps of the finite-impulse response equalizer depends on the number of conferencing rounds. Analysis in the low signal-to-noise ratio regime and numerical results validate the advantages of conferencing as a complementary technology to multicell processing.

  8. Impact of Channel Asymmetry on Base Station Cooperative Transmission with Limited Feedback

    CERN Document Server

    Hou, Xueying

    2010-01-01

    Base station (BS) cooperative transmission, also known as coordinated multi-point transmission (CoMP), is an effective way to avoid inter-cell interference in universal frequency reuse cellular systems. To gain the promised benefit, however, huge feedback overhead is in demand to gather the channel information. In this paper, we analyze the impact of channel asymmetry, which is inherent in CoMP systems, on downlink BS cooperative transmission with limited feedback. We analyze the per-user rate loss of a multi-user CoMP system led by quantization. Per-cell quantization of multicell channels is considered, which quantizes the local channel and cross channel separately and is more feasible in practice. From both the analytical and simulation results, we provide a whole picture on various critical factors that lead to the performance loss. Specifically, we show that the per user rate loss led by limited feedback depends on the location of its paired users, except for relying on its own signal to noise ratio and t...

  9. Impact of Channel Asymmetry on Performance of Channel Estimation and Precoding for Downlink Base Station Cooperative Transmission

    CERN Document Server

    Hou, Xueying; Kiong, Buon; Lau,

    2010-01-01

    Base station (BS) cooperative transmission can improve the spectrum efficiency of cellular systems, whereas using which the channels will become asymmetry. In this paper, we study the impact of the asymmetry on the performance of channel estimation and precoding in downlink BS cooperative multiple-antenna multiple-carrier systems. We first present three linear estimators which jointly estimate the channel coefficients from users in different cells with minimum mean square error, robust design and least square criterion, and then study the impact of uplink channel asymmetry on their performance. It is shown that when the large scale channel information is exploited for channel estimation, using non-orthogonal training sequences among users in different cells leads to minor performance loss. Next, we analyze the impact of downlink channel asymmetry on the performance of precoding with channel estimation errors. Our analysis shows that although the estimation errors of weak cross links are large, the resulting r...

  10. Throughput of Cellular Systems with Conferencing Mobiles and Cooperative Base Stations

    OpenAIRE

    Somekh O; Poor HV; Shamai (Shitz) S; Kramer G.; Simeone O.

    2008-01-01

    This paper considers an enhancement to multicell processing for the uplink of a cellular system, whereby the mobile stations are allowed to exchange messages on orthogonal channels of fixed capacity (conferencing). Both conferencing among mobile stations in different cells and in the same cell (inter- and intracell conferencing, resp.) are studied. For both cases, it is shown that a rate-splitting transmission strategy, where part of the message is exchanged on the conferencing channels and ...

  11. Cellular Systems with Full-Duplex Compress-and-Forward Relaying and Cooperative Base Stations

    CERN Document Server

    Somekh, Oren; Poor, H Vincent; Shamai, Shlomo

    2008-01-01

    In this paper the advantages provided by multicell processing of signals transmitted by mobile terminals (MTs) which are received via dedicated relay terminals (RTs) are studied. It is assumed that each RT is capable of full-duplex operation and receives the transmission of adjacent relay terminals. Focusing on intra-cell TDMA and non-fading channels, a simplified relay-aided uplink cellular model based on a model introduced by Wyner is considered. Assuming a nomadic application in which the RTs are oblivious to the MTs' codebooks, a form of distributed compress-and-forward (CF) scheme with decoder side information is employed. The per-cell sum-rate of the CF scheme is derived and is given as a solution of a simple fixed point equation. This achievable rate reveals that the CF scheme is able to completely eliminate the inter-relay interference, and it approaches a ``cut-set-like'' upper bound for strong RTs transmission power. The CF rate is also shown to surpass the rate of an amplify-and-forward scheme via ...

  12. Discussion of Base Station Room Development Trend under Multi-Network Cooperation%多网协同下基站机房发展趋势探讨

    Institute of Scientific and Technical Information of China (English)

    钱会; 贝斐峰; 王强

    2013-01-01

    随着通信技术的发展,国内的移动通信网络将面临2G/3G/LTE/WLAN等多网协同的网络建设,网络复用程度的大幅提高对于基站机房的建设也提出了新的要求。首先阐述了基站机房的发展历史,并介绍了基站机房现阶段典型的机房类型及其优缺点,研究了通信行业的发展背景及趋势。最后对基站机房的未来发展趋势进行总结,说明了基站机房未来发展对现网的影响。%With the development of communication technology, the domestic mobile communication network will face 2G/3G/LTE/WLAN multi-network cooperation construction. The increasing network multiplexing degree also has new requirements for the construction of base station room. Firstly, the development history of base station room is given. Secondly the typical types as well as the advantages and disadvantages of base station room at the present stage are introduced, then the development background and trend of communication industry are studied. Finally, the development trend of the future base station room is summarized, while the impact of the future base station room on the existing network is illustrated.

  13. Designing for cooperation at a Radio Station

    DEFF Research Database (Denmark)

    Kensing, F.; Simonsen, Jesper; Bødker, Keld

    1997-01-01

    We address computer support for work and its coordination in one of the radio channels of the Danish Broadcasting Corporation. Based upon ethnographically inspired analysis and participatory design techniques, we propose design solutions now implemented or under implementation. We focus on cooper......We address computer support for work and its coordination in one of the radio channels of the Danish Broadcasting Corporation. Based upon ethnographically inspired analysis and participatory design techniques, we propose design solutions now implemented or under implementation. We focus...... on cooperative aspects within and among the radio channel's editorial units, and between editorial units and the editorial board. Finally, we discuss technical and organisational aspects of the design, seen in light of recent CSCW concepts....

  14. A User Cooperation Stimulating Strategy Based on Cooperative Game Theory in Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Ping Zhang

    2009-01-01

    Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including “what is each node's best reaction to maximize its utility?” and “what is the optimal reimbursement to encourage cooperation?” Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.

  15. Secure base stations

    NARCIS (Netherlands)

    Bosch, Peter; Brusilovsky, Alec; McLellan, Rae; Mullender, Sape; Polakos, Paul

    2009-01-01

    With the introduction of the third generation (3G) Universal Mobile Telecommunications System (UMTS) base station router (BSR) and fourth generation (4G) base stations, such as the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) Evolved Node B (eNB), it has become important to se

  16. 75 FR 43915 - Basin Electric Power Cooperative: Deer Creek Station

    Science.gov (United States)

    2010-07-27

    ... purchasing power on the volatile open electric market. The Action Alternative at White Site 1 would be... Rural Utilities Service Basin Electric Power Cooperative: Deer Creek Station AGENCY: Rural Utilities... CFR Part 1794), and the Western Area Power Administration's (Western) NEPA implementing regulations...

  17. 75 FR 8153 - Nebraska Public Power District; Cooper Nuclear Station Environmental Assessment and Finding of No...

    Science.gov (United States)

    2010-02-23

    ... COMMISSION Nebraska Public Power District; Cooper Nuclear Station Environmental Assessment and Finding of No... District (NPPD, the licensee), for operation of the Cooper Nuclear Station (CNS), located in Nemaha County... Statement for the Cooper Nuclear Station dated February 1973. Agencies and Persons Consulted In...

  18. Cooperative processing data bases

    Science.gov (United States)

    Hasta, Juzar

    1991-01-01

    Cooperative processing for the 1990's using client-server technology is addressed. The main theme is concepts of downsizing from mainframes and minicomputers to workstations on a local area network (LAN). This document is presented in view graph form.

  19. Mechanisms for similarity based cooperation

    Science.gov (United States)

    Traulsen, A.

    2008-06-01

    Cooperation based on similarity has been discussed since Richard Dawkins introduced the term “green beard” effect. In these models, individuals cooperate based on an aribtrary signal (or tag) such as the famous green beard. Here, two different models for such tag based cooperation are analysed. As neutral drift is important in both models, a finite population framework is applied. The first model, which we term “cooperative tags” considers a situation in which groups of cooperators are formed by some joint signal. Defectors adopting the signal and exploiting the group can lead to a breakdown of cooperation. In this case, conditions are derived under which the average abundance of the more cooperative strategy exceeds 50%. The second model considers a situation in which individuals start defecting towards others that are not similar to them. This situation is termed “defective tags”. It is shown that in this case, individuals using tags to cooperate exclusively with their own kind dominate over unconditional cooperators.

  20. 75 FR 52997 - Nebraska Public Power District; Cooper Nuclear Station; Exemption

    Science.gov (United States)

    2010-08-30

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Nebraska Public Power District; Cooper Nuclear Station; Exemption 1.0 Background Nebraska Public... authorizes operation of the Cooper Nuclear Station (CNS). The license provides, among other things, that...

  1. 75 FR 47856 - Nebraska Public Power District: Cooper Nuclear Station; Notice of Availability of the Final...

    Science.gov (United States)

    2010-08-09

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Nebraska Public Power District: Cooper Nuclear Station; Notice of Availability of the Final... operation for the Cooper Nuclear Station (CNS). CNS is located near Brownville, Nebraska, on the...

  2. 75 FR 10517 - Nebraska Public Power District, Cooper Nuclear Station; Exemption

    Science.gov (United States)

    2010-03-08

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Nebraska Public Power District, Cooper Nuclear Station; Exemption 1.0 Background Nebraska Public... authorizes operation of the Cooper Nuclear Station (CNS). The license provides, among other things, that...

  3. 75 FR 76055 - Nebraska Public Power District Cooper Nuclear Station; Notice of Issuance of Renewed Facility...

    Science.gov (United States)

    2010-12-07

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Docket No. 50-298; NRC-2008-0617] Nebraska Public Power District Cooper Nuclear Station; Notice of... operator of the Cooper Nuclear Station (CNS). Renewed facility operating license No. DPR-46...

  4. Distributed Cooperative Control of Multi Flywheel Energy Storage System for Electrical Vehicle Fast Charging Stations

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Quintero, Juan Carlos Vasquez

    2015-01-01

    Plug-in electrical vehicles will play a critical role in future smart grid and sudden connection of electrical vehicles chargers may cause huge power-peaks with high slew-rates on grid. In order to cope with this issue, this paper applies a distributed cooperative control for fast charging station...... consensus based voltage observer by communicating with its neighbors. The control system can realize the power balancing and DC voltage regulation with low reliance on communications. Finally, real-time hardware-in-the-loop results have been reported in order to verify the feasibility of proposed approach....

  5. 78 FR 40519 - Cooper Nuclear Station; Application and Amendment to Facility Operating License Involving...

    Science.gov (United States)

    2013-07-05

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Cooper Nuclear Station; Application and Amendment to Facility Operating License Involving Proposed... No. DPR-46, issued to Nebraska Public Power District (the licensee), for operation of the...

  6. Ideas for a Cooperative Software Development for Future GGOS Stations

    Science.gov (United States)

    Neidhardt, A.; Ettl, M.

    2012-12-01

    The development of software is a creative process, which offers a huge degree of freedom. In scientific fields a lot of researchers develop their own software for specific needs. Everyone has their own preferences and backgrounds regarding the used programming languages, styles, and platforms. This complexity results in software which is not always directly usable by others in the communities. In addition, the software is often error-prone as hidden bugs are not always revealed. Therefore ideas came up to solve these problems at the Geodetic Observatory Wettzell. The results were coding layouts and policies, documentation strategies, the usage of version control, and a consistent process of continuous integration. Within this, the discussed quality factors can define quality metrics which help to quantize code quality. The resulting software is a repository of tested modules that can be used in different programs for the geodetic space techniques. This is one possible contribution to future GGOS stations.

  7. Results from installation of waterlance soot blowers at Dairyland Power Cooperative`s JPM station

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.L. [Dairyland Power Cooperative, La Crosse, WI (United States)

    1995-06-01

    Waterlance soot blowers were installed at the John P. Madgett (JPM) Station in 1992. Improvements in cleaning the furnace and wing wall areas have reduced furnace exit temperature, superheat and reheat sprays, the gas temperature entering the hot side precipitator and NO{sub x} emissions from the Boiler. Overall savings from the waterlances exceeds $11,000,000 in avoided costs and fuel savings. This paper discusses the installation and savings realized from the waterlances at the JPM station.

  8. Operation Management of International Space Station Based on International Cooperation%美国通过国际合作实现国际空间站运行管理

    Institute of Scientific and Technical Information of China (English)

    刘阳子

    2014-01-01

    Space exploration is a tough job, drawing resources, technology and personnel from different countries around the world as countries conducting activities in outer space needs. Therefore, the development of international cooperation has become the essential initiatives for the countries which develop their national space industry and promote the interests from each other’s. The United States is a charter member of the International Space Station, through close collaboration with Russia and other members to conduct operation maintenance and management of the International Space Station. In this paper, we study the cooperation and management mode of NASA, especially its role and responsibility in the International Space Station, to provide reference for improving the management level of space international cooperation projects in China.%空间探索既复杂艰巨又耗资甚大,因此,世界各国无论从技术上还是资金上都难以独自开展,中国概莫能外。当前,国际空间站运行形成了以美国主导,各国“精诚合作”的管理模式。美国作为国际空间站的发起国,通过与俄罗斯等成员国的密切协作,实现了对国际空间站运行的维护和有效管理。国际合作成为各国发展航天事业、获取空间资源、提升技术能力的必经之路。通过对国际空间站合作管理模式尤其是美国国家航空航天局在其中所起的作用和担负的职责进行分析和研究,期望为提高我国航天国际合作项目的管理水平提供借鉴和参考。

  9. 基站协作OFDMA系统中面向混合业务的资源分配%Resource Allocation for Heterogeneous Services in OFDMA Systems with Base Station Cooperation

    Institute of Scientific and Technical Information of China (English)

    贾亦真; 陶晓明; 陆建华

    2011-01-01

    基站协作是多小区OFDMA系统中抑制共信道干扰、提高系统容量的有效手段.如何分配无线资源以实现资源与业务最佳匹配是基站协作OFDMA系统中的关键问题.现有的研究大多面向单一业务.该文研究了尽力而为(BE)与有速率约束(RC)两类典型业务共存情况下的子载波与功率分配问题,提出了一种两阶段的启发式算法.算法的第1阶段仅为RC用户分配资源,通过引入子载波价值矩阵,最小化满足RC用户速率约束所需的子载波数;第2阶段将剩余子载波分配给BE用户以最大化他们的和速率.仿真结果表明,所提算法在系统中断概率及BE用户和速率两项指标上均优于已有方法.%Base Station Cooperation (BSC) is considered as a promising way for Co-Channel Interference (CCI) mitigation and system capacity improvement in multicell OFDMA systems. How to allocate radio resource optimally to guarantee the quality of services is a key problem in OFDMA systems with BSC Previous research mostly focuses on the case of homogenous service. This paper studies subcarrier and power allocation problem in such a system where users with Best Effort (BE) service and those with Rate-Constrained (RC) service coexist. A two-stage heuristic algorithm is proposed. In the first stage, the algorithm allocates resource to only RC users, trying to minimize the number of subcarriers needed to satisfy their rate requirements with the help of value matrix of subcarriers. In the second stage, the remaining subcarriers are assigned optimally to BE users to maximize then-sum rate. Simulation results show that the proposed algorithm outperforms the counterparts in both system outage probability and BE users' sum rate.

  10. Successful operation of a cooperative SLR station of China and Argentina in San Juan

    Institute of Scientific and Technical Information of China (English)

    HAN YanBen; E ALONSO; XIANG QingGe; HUANG DongPing; YIN ZhiQiang; LIU WeiDong; E ACTIS; R PODESTA; WANG TanQiang; GUO TangYong; QU Feng; A M PACHECO; AA GONZALEZ

    2008-01-01

    We introduced the observations and researches using a Satellite Laser Ranging (SLR) system with high precision,which was designed and made in China and installed in the Observatory of San Juan Uni-versity,Argentina,the capability of the system and the achievement of the cooperative procedure be-tween China and Argentina.The SLR station in San Juan,set up by China and Argentina,is quite sig-nificant for improving the distribution of SLR stations and enhancing the orbital coverage of the whole earth.Since the SLR system started to work in the Observatory of San Juan University in the beginning of 2006,the operation is rather good,and rich data with high precision have been obtained.Further plan of the cooperation for the near future is also presented.

  11. Jigsaw Cooperative Learning: Acid-Base Theories

    Science.gov (United States)

    Tarhan, Leman; Sesen, Burcin Acar

    2012-01-01

    This study focused on investigating the effectiveness of jigsaw cooperative learning instruction on first-year undergraduates' understanding of acid-base theories. Undergraduates' opinions about jigsaw cooperative learning instruction were also investigated. The participants of this study were 38 first-year undergraduates in chemistry education…

  12. Jigsaw Cooperative Learning: Acid-Base Theories

    Science.gov (United States)

    Tarhan, Leman; Sesen, Burcin Acar

    2012-01-01

    This study focused on investigating the effectiveness of jigsaw cooperative learning instruction on first-year undergraduates' understanding of acid-base theories. Undergraduates' opinions about jigsaw cooperative learning instruction were also investigated. The participants of this study were 38 first-year undergraduates in chemistry education…

  13. DMA Reference Base Station Network Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data (15,904 records documenting 9,090 worldwide gravity base stations) were gathered by various governmental organizations (and academia) using a variety of...

  14. development development of base transceiver station selection ...

    African Journals Online (AJOL)

    eobe

    Placement of base transceiver station (BTSs) by different operators on a particular site as ... Although the International Commission on Non-Ionizing Radiation Protection (ICNIRP) viewed that ..... vacant space on the AIRTEL mast which could.

  15. Historical record of Landsat global coverage: mission operations, NSLRSDA, and International Cooperator stations

    Science.gov (United States)

    Goward, Samuel; Arvidson, Terry; Williams, Darrel; Faundeen, John; Irons, James; Franks, Shannon

    2006-01-01

    The long-term, 34 year record of global Landsat remote sensing data is a critical resource to study the Earth system and human impacts on this system. The National Satellite Land Remote Sensing Data Archive (NSLRSDA) is charged by public law to: “maintain a permanent, comprehensive Government archive of global Landsat and other land remote sensing data for long-term monitoring and study of the changing global environment” (U.S. Congress, 1992). The advisory committee for NSLRSDA requested a detailed analysis of observation coverage within the U.S. Landsat holdings, as well as that acquired and held by International Cooperator (IC) stations. Our analyses, to date, have found gaps of varying magnitude in U.S. holdings of Landsat global coverage data, which appear to reflect technical or administrative variations in mission operations. In many cases it may be possible to partially fill these gaps in U.S. holdings through observations that were acquired and are now being held at International Cooperator stations.

  16. A super base station based centralized network architecture for 5G mobile communication systems

    Directory of Open Access Journals (Sweden)

    Manli Qian

    2015-04-01

    Full Text Available To meet the ever increasing mobile data traffic demand, the mobile operators are deploying a heterogeneous network with multiple access technologies and more and more base stations to increase the network coverage and capacity. However, the base stations are isolated from each other, so different types of radio resources and hardware resources cannot be shared and allocated within the overall network in a cooperative way. The mobile operators are thus facing increasing network operational expenses and a high system power consumption. In this paper, a centralized radio access network architecture, referred to as the super base station (super BS, is proposed, as a possible solution for an energy-efficient fifth-generation (5G mobile system. The super base station decouples the logical functions and physical entities of traditional base stations, so different types of system resources can be horizontally shared and statistically multiplexed among all the virtual base stations throughout the entire system. The system framework and main functionalities of the super BS are described. Some key technologies for system implementation, i.e., the resource pooling, real-time virtualization, adaptive hardware resource allocation are also highlighted.

  17. Designing Dexter-based cooperative hypermedia systems

    DEFF Research Database (Denmark)

    Grønbæk, Kaj; Madsen, Ole Lehrmann; Sloth, Lennard

    1993-01-01

    This paper discusses issues for the design of a Dexter-based cooperative hypermedia architecture and a specific system, DeVise Hypermedia (DHM), developed from this architecture. The Dexter Hypertext Reference Model [Hala90] was used as basis for designing the architecture. The Dexter model...

  18. Energy Efficient Military Mobile Base Station Placement

    Directory of Open Access Journals (Sweden)

    Saikat Ray

    2010-11-01

    Full Text Available This research deals with an energy efficient network for military mobile base station placement. Theproposed method is based on minimizing the energy loss of military communication networks where thebase station is moving along a preset path and the users are constantly moving in an independent speedand direction. It takes into account the free space loss and the knife edge effect for the energy loss toestablish a path weight for the shortest path model. Then, it evaluates the neighboring points to the basestation for the energy loss of the network in order to find the position at which the minimum energy lossoccurs. The results show a clear energy saving advantage when compared to Lloyd-Max’s method

  19. Lunar Base Thermoelectric Power Station Study

    Science.gov (United States)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, Gerhard; Brooks, Michael; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Space Power Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) Task, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing, and promising candidates for the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as a lunar base power station where kilowatts of power would be required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this particular mission concept. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed as well as transport issues for this concept. The goal of the study was to review the entire life cycle of the

  20. Antenna unit and radio base station therewith

    Science.gov (United States)

    Kuwahara, Mikio; Doi, Nobukazu; Suzuki, Toshiro; Ishida, Yuji; Inoue, Takashi; Niida, Sumaru

    2007-04-10

    Phase and amplitude deviations, which are generated, for example, by cables connecting an array antenna of a CDMA base station and the base station, are calibrated in the baseband. The base station comprises: an antenna apparatus 1; couplers 2; an RF unit 3 that converts a receive signal to a baseband signal, converts a transmit signal to a radio frequency, and performs power control; an A/D converter 4 for converting a receive signal to a digital signal; a receive beam form unit 6 that multiplies the receive signal by semi-fixed weight; a despreader 7 for this signal input; a time-space demodulator 8 for demodulating user data; a despreader 9 for probe signal; a space modulator 14 for user data; a spreader 13 for user signal; a channel combiner 12; a Tx calibrater 11 for controlling calibration of a signal; a D/A converter 10; a unit 16 for calculation of correlation matrix for generating a probe signal used for controlling an Rx calibration system and a TX calibration system; a spreader 17 for probe signal; a power control unit 18; a D/A converter 19; an RF unit 20 for probe signal; an A/D converter 21 for signal from the couplers 2; and a despreader 22.

  1. Cooperating expert systems for Space Station - Power/thermal subsystem testbeds

    Science.gov (United States)

    Wong, Carla M.; Weeks, David J.; Sundberg, Gale R.; Healey, Kathleen L.; Dominick, Jeffrey S.

    1988-01-01

    The Systems Autonomy Demonstration Project (SADP) is a NASA-sponsored series of increasingly complex demonstrations to show the benefits of integrating knowledge-based systems with conventional process control in real-time, real-world problem domains that can facilitate the operations and availability of major Space Station distributed systems. This paper describes the system design, objectives, approaches, and status of each of the testbed knowledge-based systems. Simplified schematics of the systems are shown.

  2. On the Cooperation of Jiangmen City with Guangzhou Experimental Station,CATAS in Agricultural Development

    Institute of Scientific and Technical Information of China (English)

    Yongqing; ZHENG; Zhiyang; LI; Qiongyan; LI; Shouxing; WEI

    2013-01-01

    Guangdong Province is one of the provinces in China with the best modern agricultural industry and the highest production efficiency.While Jiangmen City,one of the agriculture-based cities in Guangdong Province,has made active exploration in building a modern agricultural system.China has established cooperation with the four largest agricultural research institutes in China to offer technical support for the development of modern agriculture.In this paper,the status quo and existing problems of agricultural development in Jiangmen,Guangdong are briefly introduced.Then,the cooperation status and prospect of local government with the research institutes are discussed.Finally some suggestions are given on the agricultural development pattern in Jiangmen City.

  3. Automation for a base station stability testing

    OpenAIRE

    2016-01-01

    This Batchelor’s thesis was commissioned by Oy LM Ericsson Ab Oulu. The aim of it was to help to investigate and create a test automation solution for the stability testing of the LTE base station. The main objective was to create a test automation for a predefined test set. This test automation solution had to be created for specific environments and equipment. This work included creating the automation for the test cases and putting them to daily test automation jobs. The key factor...

  4. Mitigating the Effects of Mobility and Synchronization Error in OFDM based Cooperative Communication Systems

    Directory of Open Access Journals (Sweden)

    Bereket Babiso Yetera

    2014-08-01

    Full Text Available An Orthogonal Frequency Division Multiplexing based mobile wireless network with a sender, a destination and a third station acting as a cooperating node is modelled and analyzed. The length of cyclic prefix in the orthogonal frequency division multiplexed symbols is made to vary depending on the channel conditions and maximum likelihood estimator is used at the receiver in order to compensate for the carrier frequency offset that occurs during transmission. Simulation results show that maximum likelihood estimator has better performance than self-cancellation estimations. The channels between the source, the cooperating node and the destination are modelled containing thermal noise, Rayleigh fading, Rician fading and path loss. Amplify-and-Forward cooperation protocol is used at the cooperating node when the system is in cooperation mode. For a relatively short distance between the cooperating nodes, when compared to the distance between them and the base station, amplify and forward cooperation protocol has a better performance than decode-and forward protocol, unless an error correcting code is simulated. The cooperating node turns its cooperation mode switch ON or OFF depending on the channel state between the source and the cooperating nodes.  The performance of different combination protocols at the receiver is simulated and maximum ratio combining is found to have better performance. However, for immobile wireless sensor networks Extended SNR (ESNR combiner has also better performance. The system has also showed that with any kind of combination protocol at the receiver it is possible to achieve second order diversity when there is only one cooperating node in the system.

  5. GPP-Based Soft Base Station Designing and Optimization

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Tao; Yan-Zhao Hou; Kai-Dong Wang; Hai-Yang He; Y.Jay Guo

    2013-01-01

    It is generally acknowledged that mobile communication base stations are composed of hardware components such as Field Programming Gate Array (FPGA),Digital Signal Processor (DSP),which promise reliable and fluent services for the mobile users.However,with the increasing demand for energy-efficiency,approaches of low power-consumption and high-flexibility are needed urgently.In this circumstance,General Purpose Processor (GPP) attracts people's attention for its low-cost and flexibility.Benefited from the development of modern GPP in multi-core,Single Instruction Multiple Data (SIMD) instructions,larger cache,etc.,GPPs are capable of performing high-density digital processing.In this paper,we compare several software-defined radio (SDR) prototypes and propose the general architecture of GPP-based soft base stations.Then,the schematic design of resource allocation and algorithm optimization in soft base station implementation are studied.As an application example,a prototype of GPP-based soft base station referring to the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is realized and evaluated.To the best of our knowledge,it is the first Soft-LTE prototype ever reported.In the end,we evaluate the timing performance of the LTE soft base station and a packet loss ratio of less than 0.003 is obtained.

  6. Ameliorated GA approach for base station planning

    Science.gov (United States)

    Wang, Andong; Sun, Hongyue; Wu, Xiaomin

    2011-10-01

    In this paper, we aim at locating base station (BS) rationally to satisfy the most customs by using the least BSs. An ameliorated GA is proposed to search for the optimum solution. In the algorithm, we mesh the area to be planned according to least overlap length derived from coverage radius, bring into isometric grid encoding method to represent BS distribution as well as its number and develop select, crossover and mutation operators to serve our unique necessity. We also construct our comprehensive object function after synthesizing coverage ratio, overlap ratio, population and geographical conditions. Finally, after importing an electronic map of the area to be planned, a recommended strategy draft would be exported correspondingly. We eventually import HongKong, China to simulate and yield a satisfactory solution.

  7. Colour based sorting station with Matlab simulation

    Directory of Open Access Journals (Sweden)

    Constantin Victor

    2017-01-01

    Full Text Available The paper presents the design process and manufacturing elements of a colour-based sorting station. The system is comprised of a gravitational storage, which also contains the colour sensor. Parts are extracted using a linear pneumatic motor and are fed onto an electrically driven conveyor belt. Extraction of the parts is done at 4 points, using two pneumatic motors and a geared DC motor, while the 4th position is at the end of the belt. The mechanical parts of the system are manufactured using 3D printer technology, allowing for easy modification and adaption to the geometry of different parts. The paper shows all of the stages needed to design, optimize, test and implement the proposed solution. System optimization was performed using a graphical Matlab interface which also allows for sorting algorithm optimization.

  8. Connectivity Maintenance Based on Multiple Relay UAVs Selection Scheme in Cooperative Surveillance

    Directory of Open Access Journals (Sweden)

    Qian Zhu

    2016-12-01

    Full Text Available For the purpose of remote command and situation awareness, multiple unmanned aerial vehicles (UAVs cooperative surveillance with a ground station via multihop communications is presented in this paper. Considering limited communication capacities, a reliable UAV-to-UAV communication relay chain is dynamically established for connectivity maintenance and real-time surveillance information transmission. Firstly, a multiple UAVs cooperative surveillance framework is constructed with history detection information and surveillance payoff estimation. Secondly, four attributes are proposed to characterize differences among UAV alternatives in communication network containing a ground station, and a novel multiple relay UAVs selection scheme based on fuzzy optimum selection is developed to achieve tradeoff between surveillance mission and connectivity maintenance. Furthermore, satisfied with collision avoidance, limited communication and UAV kinematic constraints, the optimal UAV motion plan is obtained by decentralized receding horizon control, which is solved by particle swarm optimization with elite mechanism. Simulations demonstrate the effectiveness of the proposed methods in multi UAVs cooperative surveillance.

  9. COOPERATIVE CLUSTERING BASED ON GRID AND DENSITY

    Institute of Scientific and Technical Information of China (English)

    HU Ruifei; YIN Guofu; TAN Ying; CAI Peng

    2006-01-01

    Based on the analysis of features of the grid-based clustering method-clustering in quest(CLIQUE) and density-based clustering method-density-based spatial clustering of applications with noise (DBSCAN), a new clustering algorithm named cooperative clustering based on grid and density(CLGRID) is presented. The new algorithm adopts an equivalent rule of regional inquiry and density unit identification. The central region of one class is calculated by the grid-based method and the margin region by a density-based method. By clustering in two phases and using only a small number of seed objects in representative units to expand the cluster, the frequency of region query can be decreased, and consequently the cost of time is reduced. The new algorithm retains positive features of both grid-based and density-based methods and avoids the difficulty of parameter searching. It can discover clusters of arbitrary shape with high efficiency and is not sensitive to noise. The application of CLGRID on test data sets demonstrates its validity and higher efficiency, which contrast with traditional DBSCAN with R* tree.

  10. User Context Aware Base Station Power Flow Model

    OpenAIRE

    Walsh, Barbara; Farrell, Ronan

    2005-01-01

    At present the testing of power amplifiers within base station transmitters is limited to testing at component level as opposed to testing at the system level. While the detection of catastrophic failure is possible, that of performance degradation is not. This paper proposes a base station model with respect to transmitter output power with the aim of introducing system level monitoring of the power amplifier behaviour within the base station. Our model reflects the expe...

  11. Market based framework for multiple AUVs cooperation

    Institute of Scientific and Technical Information of China (English)

    YOU Guang-xin; PANG Yong-jie; JIANG Da-peng

    2005-01-01

    A"Market" based framework for multiple AUVs team is introduced in this paper.It is a distributed meta-level task allocation framwork. The formulation and the basic concepts of the "Market" such as "goods" and "price" are discussed first, then the basic algorithm of the "auction". The loosely coupled v-MDTSP tasks are considered as an example of the task allocation mission. A multiple AUV team controller and a detailed algorithm are developed for such applications. The simulation results show that the controller has the advantages such as robustness and low complexity and it can achieve better optimization results than the classical central controller (such as GA) in some tasks. And the comparison of two different local solvers also implies that we should get the reasonable task allocation even not using the high quality algorithm, which can considerably decrease the cooperation computation.

  12. Compressed Sensing-Based Multiuser Cooperative Networks

    Institute of Scientific and Technical Information of China (English)

    付晓梅; 崔阳然

    2016-01-01

    To avoid interference, compressed sensing is introduced into multiuser cooperative network. A coopera-tive compressed sensing and amplify-and-forward(CCS-AF)scheme is proposed, and it is proved that the channel capacity increases compared with the traditional cooperative scheme by considering the CCS-AF transmission ma-trix as the measurement matrix. Moreover, a new power allocation algorithm among the relays is proposed to im-prove the channel capacity. Numerical results validate the effectiveness of the proposed scheme.

  13. Web-based Cooperative Learning in College Chemistry Teaching

    Directory of Open Access Journals (Sweden)

    Bin Jiang

    2014-03-01

    Full Text Available With the coming of information era, information process depend on internet and multi-media technology in education becomes the new approach of present teaching model reform. Web-based cooperative learning is becoming a popular learning approach with the rapid development of web technology. The paper aims to how to carry out the teaching strategy of web-based cooperative learning and applied in the foundation chemistry teaching.It was shown that with the support of modern web-based teaching environment, students' cooperative learning capacity and overall competence can be better improved and the problems of interaction in large foundation chemistry classes can be solved. Web-based cooperative learning can improve learning performance of students, what's more Web-based cooperative learning provides students with cooperative skills, communication skills, creativity, critical thinking skills and skills in information technology application.

  14. Metric-Based Cooperative Routing in Multihop Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Xin He

    2012-01-01

    Full Text Available Cooperative communication fully leverages the broadcast nature of wireless channels and exploits time/spatial diversity in a distributed manner, thereby achieving significant improvements in system capacity and transmission reliability. Cooperative diversity has been well studied from the physical layer perspective. Thereafter, cooperative MAC design has also drawn much attention recently. However, very little work has addressed cooperation at the routing layer. In this paper, we propose a simple yet efficient scheme for cooperative routing by using cooperative metrics including packet delivery ratio, throughput, and energy consumption efficiency. To make a routing decision based on our scheme, a node needs to first determine whether cooperation on each link is necessary or not, and if necessary, select the optimal cooperative scheme as well as the optimal relay. To do so, we calculate and compare cooperative routing metric values for each potential relay for each different cooperative MAC scheme (C-ARQ and CoopMAC in this study, and further choose the best value and compare it with the noncooperative link metric. Using the final optimal metric value instead of the traditional metric value at the routing layer, new optimal paths are set up in multihop ad hoc networks, by taking into account the cooperative benefits from the MAC layer. The network performance of the cooperative routing solution is demonstrated using a simple network topology.

  15. Amplification of Cooper pair splitting current in a graphene-based Cooper pair beam splitter geometry

    Science.gov (United States)

    Islam, SK Firoz; Saha, Arijit

    2017-09-01

    Motivated by the recent experiments [Scientific Reports 6, 23051 (2016), 10.1038/srep23051; Phys. Rev. Lett. 114, 096602 (2015), 10.1103/PhysRevLett.114.096602], we theoretically investigate Cooper pair splitting current in a graphene-based Cooper pair beam splitter geometry. By considering the graphene-based superconductor as an entangler device, instead of normal [two-dimensional (2D)] BCS superconductor, we show that the Cooper pair splitting current mediated by the crossed Andreev process is amplified compared to its normal superconductor counterpart. This amplification is attributed to the strong suppression of the local normal Andreev reflection process (arising from the Cooper pair splitting) from the graphene-based superconductor to lead via the same quantum dot, in comparison to the usual 2D superconductor. Due to the vanishing density of states at the Dirac point of undoped graphene, a doped graphene-based superconductor is considered here and it is observed that Cooper pair splitting current is very insensitive to the doping level in comparison to the usual 2D superconductor. The transport process of nonlocal spin-entangled electrons also depends on the type of pairing, i.e., whether the electron-hole pairing is onsite, intersublattice or the combination of both. The intersublattice pairing of graphene causes the maximum nonlocal Cooper pair splitting current, whereas the presence of both pairings reduces the Cooper pair splitting current.

  16. A Review on RF Field Exposure from Cellular Base Stations

    National Research Council Canada - National Science Library

    Amar Renke; Mahesh Chavan

    2014-01-01

      This review paper, takes into account previously published papers based on human exposure to electromagnetic fields which is radiated from cellular base stations and its corresponding adverse effects on human beings...

  17. Installation of Ohio's First Electrolysis-Based Hydrogen Fueling Station

    Science.gov (United States)

    Scheidegger, Brianne T.; Lively, Michael L.

    2012-01-01

    This paper describes progress made towards the installation of a hydrogen fueling station in Northeast Ohio. In collaboration with several entities in the Northeast Ohio area, the NASA Glenn Research Center is installing a hydrogen fueling station that uses electrolysis to generate hydrogen on-site. The installation of this station is scheduled for the spring of 2012 at the Greater Cleveland Regional Transit Authority s Hayden bus garage in East Cleveland. This will be the first electrolysis-based hydrogen fueling station in Ohio.

  18. A Cooperation-planning Model Based on Bilevel Programming Decision

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jianfeng; ZHOU Lei; BAO Zhenqiang; BIAN Wenyu; LI Xiangqing

    2006-01-01

    This paper is based on a resource constrained active network project; the constraint of the local resource and the time constraint of the cooperation resource are considered simultaneously. And the respective benefit of the manager and cooperation partners is also considered simultaneously. And a cooperation-planning model based on bilevel multi-objective programming is designed, according to the due time and total cost. And an extended CNP based on the permitted range for resource and time requests is presented. A larger task set in scheduling cycle is on the permitting for the request of cooperation resource and time while the task manager itself may be permitted biding for tasks. As a result, the optimization space for the cooperation planning is enlarged. So not every bidding task is successfully bid by invitee, and the task manager itself takes on some bidding tasks. Finally, the genetic algorithm is given and the validity and feasibility of the model is proved by a case.

  19. Contract-Based Cooperative Spectrum Sharing

    CERN Document Server

    Duan, Lingjie; Huang, Jianwei

    2011-01-01

    Providing proper economic incentives is essential for the success of dynamic spectrum sharing. Cooperative spectrum sharing is one effective way to achieve this goal. In cooperative spectrum sharing, secondary users (SUs) relay traffics for primary users (PUs), in exchange for dedicated transmission time for the SUs' own communication needs. In this paper, we study the cooperative spectrum sharing under incomplete information, where SUs' types (capturing their heterogeneity in relay channel gains and evaluations of power consumptions) are private information and not known by PUs. Inspired by the contract theory, we model the network as a labor market. The single PU is the employer who offers a contract to the SUs. The contract consists of a set of contract items representing combinations of spectrum accessing time (i.e., reward) and relaying power (i.e., contribution). The SUs are employees, and each of them selects the best contract item to maximize his payoff. We study the optimal contract design for both w...

  20. Radiations from GSM Base Stations and its Biological Effects on ...

    African Journals Online (AJOL)

    Michael Horsfall

    The levels of radiofrequency (RF) radiations around the base stations were found .... of Turk's solution (Glacial Acetic Acid tinted with ... dissolved in distilled, 40% formaldehyde) is balanced .... agencies in different countries have come up with.

  1. Quantum key distribution using card, base station and trusted authority

    Science.gov (United States)

    Nordholt, Jane Elizabeth; Hughes, Richard John; Newell, Raymond Thorson; Peterson, Charles Glen; Rosenberg, Danna; McCabe, Kevin Peter; Tyagi, Kush T; Dallman, Nicholas

    2015-04-07

    Techniques and tools for quantum key distribution ("QKD") between a quantum communication ("QC") card, base station and trusted authority are described herein. In example implementations, a QC card contains a miniaturized QC transmitter and couples with a base station. The base station provides a network connection with the trusted authority and can also provide electric power to the QC card. When coupled to the base station, after authentication by the trusted authority, the QC card acquires keys through QKD with a trusted authority. The keys can be used to set up secure communication, for authentication, for access control, or for other purposes. The QC card can be implemented as part of a smart phone or other mobile computing device, or the QC card can be used as a fillgun for distribution of the keys.

  2. Quantum key distribution using card, base station and trusted authority

    Energy Technology Data Exchange (ETDEWEB)

    Nordholt, Jane E.; Hughes, Richard John; Newell, Raymond Thorson; Peterson, Charles Glen; Rosenberg, Danna; McCabe, Kevin Peter; Tyagi, Kush T.; Dallmann, Nicholas

    2017-06-14

    Techniques and tools for quantum key distribution ("QKD") between a quantum communication ("QC") card, base station and trusted authority are described herein. In example implementations, a QC card contains a miniaturized QC transmitter and couples with a base station. The base station provides a network connection with the trusted authority and can also provide electric power to the QC card. When coupled to the base station, after authentication by the trusted authority, the QC card acquires keys through QKD with a trust authority. The keys can be used to set up secure communication, for authentication, for access control, or for other purposes. The QC card can be implemented as part of a smart phone or other mobile computing device, or the QC card can be used as a fillgun for distribution of the keys.

  3. Evolution of cooperation driven by social-welfare-based migration

    Science.gov (United States)

    Li, Yan; Ye, Hang; Zhang, Hong

    2016-03-01

    Individuals' migration behavior may play a significant role in the evolution of cooperation. In reality, individuals' migration behavior may depend on their perceptions of social welfare. To study the relationship between social-welfare-based migration and the evolution of cooperation, we consider an evolutionary prisoner's dilemma game (PDG) in which an individual's migration depends on social welfare but not on the individual's own payoff. By introducing three important social welfare functions (SWFs) that are commonly studied in social science, we find that social-welfare-based migration can promote cooperation under a wide range of parameter values. In addition, these three SWFs have different effects on cooperation, especially through the different spatial patterns formed by migration. Because the relative efficiency of the three SWFs will change if the parameter values are changed, we cannot determine which SWF is optimal for supporting cooperation. We also show that memory capacity, which is needed to evaluate individual welfare, may affect cooperation levels in opposite directions under different SWFs. Our work should be helpful for understanding the evolution of human cooperation and bridging the chasm between studies of social preferences and studies of social cooperation.

  4. Mobile Phone Base Station Radiation Study for Addressing Public Concern

    Directory of Open Access Journals (Sweden)

    Aiman Ismail

    2010-01-01

    Full Text Available Problem statement: The proliferation of mobile phone base stations had increased concerns from the public on the radio frequency radiation hazards that might come from them. The world wide public concern involved health risk due to radio frequency radiation. In Malaysia also public interest has increased, although it is not as intense as probably in other parts of the world, but had also resulted in tearing down of a few base stations. Due to this growing concern, a study was conducted to evaluate the radio frequency radiation levels near several mobile phone base stations in two major cities in Malaysia. Approach: Measurements in terms of electric field strength, power density and specific absorption rate were made to check the exposure level at public locations. Broadband meter were first used to survey the sites near the base stations. From the survey, spots with relatively higher readings will be further investigated using narrow band measurements. The measured values were then compared with the recommended international maximum permissible exposure limit. Results: The study showed that the measured values were found to be less than 1% of the maximum permissible exposure. Conclusion: The amount of radio frequency radiation from the selected base stations in the two major cities are adhering to the international limits although the physical radio base station infrastructures spawning out everywhere in these areas may give the reverse impression.

  5. Cooperative relay-based multicasting for energy and delay minimization

    KAUST Repository

    Atat, Rachad

    2012-08-01

    Relay-based multicasting for the purpose of cooperative content distribution is studied. Optimized relay selection is performed with the objective of minimizing the energy consumption or the content distribution delay within a cluster of cooperating mobiles. Two schemes are investigated. The first consists of the BS sending the data only to the relay, and the second scheme considers the scenario of threshold-based multicasting by the BS, where a relay is selected to transmit the data to the mobiles that were not able to receive the multicast data. Both schemes show significant superiority compared to the non-cooperative scenarios, in terms of energy consumption and delay reduction. © 2012 IEEE.

  6. Human cooperation based on punishment reputation.

    Science.gov (United States)

    dos Santos, Miguel; Rankin, Daniel J; Wedekind, Claus

    2013-08-01

    The threat of punishment usually promotes cooperation. However, punishing itself is costly, rare in nonhuman animals, and humans who punish often finish with low payoffs in economic experiments. The evolution of punishment has therefore been unclear. Recent theoretical developments suggest that punishment has evolved in the context of reputation games. We tested this idea in a simple helping game with observers and with punishment and punishment reputation (experimentally controlling for other possible reputational effects). We show that punishers fully compensate their costs as they receive help more often. The more likely defection is punished within a group, the higher the level of within-group cooperation. These beneficial effects perish if the punishment reputation is removed. We conclude that reputation is key to the evolution of punishment.

  7. Risk of Credit Cooperatives: An analysis based on the profile of the cooperated

    Directory of Open Access Journals (Sweden)

    José Roberto de Souza Francisco

    2012-12-01

    Full Text Available This work has as purpose to analyze among the credit operations, those that generate larger breach of contract risk for the cooperative, with base in the profile of the cooperated, and to identify which the strategies can be pointed to avoid possible flaws in the next credit analyses. The work was divided in three stages. The first stage refers to the National Financial System, with the objective of demonstrating as in him the Cooperatives of Credit are inserted. The second stage approaches the System of Cooperative Credit, it presents that form is structured and his/her hierarchical level. The third stage treats of the System of Risk of Credit, in the which the risk, administration and the models of credit evaluation will be analyzed. It was verified that the most appropriate models for analysis of the Cooperatives of Credit are Credit Scoring Models and Credit Bureau, us which, through statistical techniques as the analysis discriminante and regression logistics, the characteristics of considered credits of larger breach of contract risk were demonstrated. The analysis based on identifying the "worse customer", because this generates larger breach of contract risk and it influences in the financial administration. It was ended that the most relevant variables to identify the breach of contract risk were the rude monthly income and the value liberated in the credit concession, because the largest concentration of breach of contract risk.

  8. Practical Non-Uniform Channelization for Multistandard Base Stations

    Institute of Scientific and Technical Information of China (English)

    Alvaro Palomo Navarro; Rudi Villing; Ronan J. Farrell

    2011-01-01

    A multistandard software-defined radio base station must perform non-uniform channelization of multiplexed frequency bands. Non-uniform channelization accounts for a significant portion of the digital signal processing workload in the base station receiver and can be difficult to realize in a physical implementation. In non-uniform channelization methods based on generalized DFT filter banks, large prototype filter orders are a significant issue for implementation. In this paper, a multistage filter design is applied to two different non-uniform generalized DFT-based channelizers in order to reduce their filter orders. To evaluate the approach, a TETRA and TEDS base station is used. Experimental results show that the new multistage design reduces both the number of coefficients and operations and leads to a more feasible design and practical physical implementation.

  9. Mobile phone base stations-Effects on wellbeing and health.

    Science.gov (United States)

    Kundi, Michael; Hutter, Hans-Peter

    2009-08-01

    Studying effects of mobile phone base station signals on health have been discouraged by authoritative bodies like WHO International EMF Project and COST 281. WHO recommended studies around base stations in 2003 but again stated in 2006 that studies on cancer in relation to base station exposure are of low priority. As a result only few investigations of effects of base station exposure on health and wellbeing exist. Cross-sectional investigations of subjective health as a function of distance or measured field strength, despite differences in methods and robustness of study design, found indications for an effect of exposure that is likely independent of concerns and attributions. Experimental studies applying short-term exposure to base station signals gave various results, but there is weak evidence that UMTS and to a lesser degree GSM signals reduce wellbeing in persons that report to be sensitive to such exposures. Two ecological studies of cancer in the vicinity of base stations report both a strong increase of incidence within a radius of 350 and 400m respectively. Due to the limitations inherent in this design no firm conclusions can be drawn, but the results underline the urgent need for a comprehensive investigation of this issue. Animal and in vitro studies are inconclusive to date. An increased incidence of DMBA induced mammary tumors in rats at a SAR of 1.4W/kg in one experiment could not be replicated in a second trial. Indications of oxidative stress after low-level in vivo exposure of rats could not be supported by in vitro studies of human fibroblasts and glioblastoma cells. From available evidence it is impossible to delineate a threshold below which no effect occurs, however, given the fact that studies reporting low exposure were invariably negative it is suggested that power densities around 0.5-1mW/m(2) must be exceeded in order to observe an effect. The meager data base must be extended in the coming years. The difficulties of investigating

  10. The Evolution of Reputation-Based Cooperation in Regular Networks

    Directory of Open Access Journals (Sweden)

    Tatsuya Sasaki

    2017-01-01

    Full Text Available Despite recent advances in reputation technologies, it is not clear how reputation systems can affect human cooperation in social networks. Although it is known that two of the major mechanisms in the evolution of cooperation are spatial selection and reputation-based reciprocity, theoretical study of the interplay between both mechanisms remains almost uncharted. Here, we present a new individual-based model for the evolution of reciprocal cooperation between reputation and networks. We comparatively analyze four of the leading moral assessment rules—shunning, image scoring, stern judging, and simple standing—and base the model on the giving game in regular networks for Cooperators, Defectors, and Discriminators. Discriminators rely on a proper moral assessment rule. By using individual-based models, we show that the four assessment rules are differently characterized in terms of how cooperation evolves, depending on the benefit-to-cost ratio, the network-node degree, and the observation and error conditions. Our findings show that the most tolerant rule—simple standing—is the most robust among the four assessment rules in promoting cooperation in regular networks.

  11. Evolution of cooperation driven by reputation-based migration.

    Directory of Open Access Journals (Sweden)

    Rui Cong

    Full Text Available How cooperation emerges and is stabilized has been a puzzling problem to biologists and sociologists since Darwin. One of the possible answers to this problem lies in the mobility patterns. These mobility patterns in previous works are either random-like or driven by payoff-related properties such as fitness, aspiration, or expectation. Here we address another force which drives us to move from place to place: reputation. To this end, we propose a reputation-based model to explore the effect of migration on cooperation in the contest of the prisoner's dilemma. In this model, individuals earn their reputation scores through previous cooperative behaviors. An individual tends to migrate to a new place if he has a neighborhood of low reputation. We show that cooperation is promoted for relatively large population density and not very large temptation to defect. A higher mobility sensitivity to reputation is always better for cooperation. A longer reputation memory favors cooperation, provided that the corresponding mobility sensitivity to reputation is strong enough. The microscopic perception of the effect of this mechanism is also given. Our results may shed some light on the role played by migration in the emergence and persistence of cooperation.

  12. Auction-based Security Game for Multiuser Cooperative Networks

    Science.gov (United States)

    Wang, An; Cai, Yueming; Yang, Wendong; Cheng, Yunpeng

    2013-04-01

    In this paper, we develop an auction-based algorithm to allocate the relay power efficiently to improve the system secrecy rate in a cooperative network, where several source-destination pairs and one cooperative relay are involved. On the one hand, the cooperative relay assists these pairs to transmit under a peak power constraint. On the other hand, the relay is untrusty and is also a passive eavesdropper. The whole auction process is completely distributed and no instantaneous channel state information exchange is needed. We also prove the existence and uniqueness of the Nash Equilibrium (NE) for the proposed power auction game. Moreover, the Pareto optimality is also validated. Simulation results show that our proposed auction-based algorithm can effectively improve the system secrecy rate. Besides, the proposed auction-based algorithm can converge to the unique NE point within a finite number of iterations. More interestingly, we also find that the proposed power auction mechanism is cheat-proof.

  13. POWER CONTROL BASED COOPERATIVE OPPORTUNISTIC ROUTING IN WIRELESS SENSOR NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Hu Haifeng; Zhu Qi

    2009-01-01

    This paper proposes an approach called PC-CORP (Power Control based Cooperative Opportunistic Routing Protocol) for WSN (Wireless Sensor Networks), providing robustness to the random variations in network connectivity while ensuring better data forwarding efficiency in an energy efficient manner. Based on the realistic radio model, we combine the region-based routing, rendezvous scheme, sleep discipline and cooperative communication together to model data forwarding by cross layer design in WSN. At the same time, a lightweight transmission power control algorithm called PC-AIMD (Power Control Additive Increase Multiplicative Decrease) is introduced to utilize the cooperation of relay nodes to improve the forwarding efficiency performance and increase the robustness of the routing protocol. In the simulation, the performance of PC-COPR is investigated in terms of the adaptation of variations in network connectivity and satisfying the QoS requirements of application.

  14. Modified Cooperative Access with Relay’s Data (MCARD based Directional Antenna for multi-rate WLANs

    Directory of Open Access Journals (Sweden)

    Ahmed Magdy

    2014-03-01

    Full Text Available In this paper, for multi-rate wireless local area networks (WLANs, a modified protocol in Medium Access Control (MAC, called Modified Cooperative Access with Relay’s Data (MCARD based Directional Antenna using half wave length dipole in Uniform Circular Array (UCA topology is proposed. MCARD gives remote stations chance to send their information by using intermediate stations (relays to Access Point (AP at a higher data rate based practical antenna. As can be seen under MCARD, a relay station transmits its information before forwarding information from the source station because it uses directional antenna. Analytical results and simulations show that MCARD can significantly improve system quality of service (QOS in terms of throughput under different channel conditions.

  15. Robustness of a TETRA base station receiver against intentional EMI

    NARCIS (Netherlands)

    Beek, van de Stefan; Leferink, Frank

    2015-01-01

    Terrestrial trunked radio (TETRA) is a digital radio standard that was developed to meet the needs of professional mobile radio systems. TETRA is vulnerable to intentional electromagnetic interference (EMI) because of the wireless link. The EMI can easily be front door coupled to the base station vi

  16. GSM Base Stations Location Monitoring using Geographic Information System

    Directory of Open Access Journals (Sweden)

    Kuboye B. M.

    2013-06-01

    Full Text Available Global System for Mobile Communication (GSM is a digital system developed to meet the desires of the entire public. As the population of a particular area, city or country increases, the number of mobile subscribers increases too. GSM network operators have to reduce congestion on their networks in order to satisfy their subscribers, therefore, a means of monitoring the base stations' locations and the geographical area of where they are located are important factor to achieve this purpose. This work provides a simple step-by-step approach on how to monitor the location of the base stations. A review of GSM and Global Positioning System (GPS technology and their applications to the Geographic Information System (GIS are presented. The means of taken the coordinates of base stations using a GPS device is also presented. ESRI's ArcView application software was used to design the map that shows the location of the base station and thereafter was integrated into the web. It concluded with the recommendation to GSM operators in Nigeria. If the recommendations are given necessary attention, the planning and optimization of cell sites will be enhanced and thereby reduce congestion on network. As a result, the performance of Network will improve, and it will give rise to subscribers' satisfaction and increasing profit returns to the operators.

  17. Optimal Resource Allocation and Relay Selection in Bandwidth and Time Exchange Based Cooperative Forwarding

    CERN Document Server

    Islam, Muhammad Nazmul; Kompella, Sastry

    2011-01-01

    In this paper, we investigate joint optimal relay selection and resource allocation that are fundamental to the understanding of bandwidth exchange (BE) and time exchange (TE) enabled incentivized cooperative forwarding in wireless networks. We consider a network where N nodes transmit data in the uplink to an access point (AP) or base station (BS). We first consider the scenario where each node gets an initial amount (equal, optimal or arbitrary) of resource in the form of bandwidth or time, and uses this resource as a flexible incentive for two hop relaying. We focus on ?-fair network utility maximization (NUM) and total power minimization in this environment. For both BE and TE, we show the concavity or convexity of the resource allocation problem for a fixed relay set. Defining the link weights of each relay pair as the utility gain due to cooperation (over noncooperation), we show that the optimal relay selection, often a combinatorially cumbersome problem, reduces to the maximum weighted matching (MWM) ...

  18. Randomness Effect on Cooperation in Memory-Based Snowdrift Game

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ming-Feng; WANG Bing-Hong; WANG Wen-Xu; TANG Chuan-Long; YANG Rui

    2008-01-01

    @@ A memory-based snowdrift game (MBSG) on spatial small-world networks is investigated. It is found that cooperation rate versus temptation shows some step structures on small-world networks, similar to the case on regular latticcs. With the increment of rewiring probability based on four-neighbour regular lattices, more steps are observable. Interestingly, it is observed that cooperation rate peaks at a specific value of temptation,which indicates that properly encouraging selfish actions may lead to better cooperative behaviours in the MBSG on small-world networks. Memory effects are also discussed for different rewiring probabilities. Furthermore,optimal regions are found in the parameter planes. The strategy-related average degrees of individuals are helpful to understand the obtained results.

  19. Cooperative peer-to-peer multiagent based systems

    CERN Document Server

    Caram, L F; Ausloos, M; Proto, A N

    2015-01-01

    A multiagent based model for a system of cooperative agents aiming at growth is proposed. This is based on a set of generalized Verhulst-Lotka-Volterra differential equations. In this study, strong cooperation is allowed among agents having similar sizes, and weak cooperation if agent have markedly different "sizes", thus establishing a peer-to-peer modulated interaction scheme. A rigorous analysis of the stable configurations is presented first examining the fixed points of the system, next determining their stability as a function of the model parameters. It is found that the agents are self-organizing into clusters. Furthermore, it is demonstrated that, depending on parameter values, multiple stable configurations can coexist. It occurs that only one of them always emerges with probability close to one, because its associated attractor dominates over the rest. This is shown through numerical integrations and simulations,after analytic developments. In contrast to the competitive case, agents are able to in...

  20. Data communications method for mobile network in fourth generation communications system, involves delivering decoded data to mobile station from relay station, where mobile station receives data from both relay and base stations

    DEFF Research Database (Denmark)

    2008-01-01

    The method involves utilizing a base station (BS) (100) to transmit data to a relay station (RS) (110) and a mobile station (MS) (120), where the data includes two messages. The BS is utilized to transmit the two messages by utilizing a linear combination method, and the data is received in the R...

  1. Incentive Model Based on Cooperative Relationship in Sustainable Construction Projects

    Directory of Open Access Journals (Sweden)

    Guangdong Wu

    2017-07-01

    Full Text Available Considering the cooperative relationship between owners and contractors in sustainable construction projects, as well as the synergistic effects created by cooperative behaviors, a cooperative incentive model was developed using game theory. The model was formulated and analyzed under both non-moral hazard and moral hazard situations. Then, a numerical simulation and example were proposed to verify the conclusions derived from the model. The results showed that the synergistic effect increases the input intensity of one party’s resource transfer into the increase of marginal utility of the other party, thus the owner and contractor are willing to enhance their levels of effort. One party’s optimal benefit allocation coefficient is positively affected by its own output efficiency, and negatively affected by the other party’s output efficiency. The effort level and expected benefits of the owner and contractor can be improved by enhancing the cooperative relationship between the two parties, as well as enhancing the net benefits of a sustainable construction project. The synergistic effect cannot lower the negative effect of moral hazard behaviors during the implementation of sustainable construction projects. Conversely, the higher levels of the cooperative relationship, the wider the gaps amongst the optimal values under both non-moral hazard and moral hazard situations for the levels of effort, expected benefits and net project benefits. Since few studies to date have emphasized the effects of cooperative relationship on sustainable construction projects, this study constructed a game-based incentive model to bridge the gaps. This study contributes significant theoretical and practical insights into the management of cooperation amongst stakeholders, and into the enhancement of the overall benefits of sustainable construction projects.

  2. Performance Analysis of 3D Massive MIMO Cellular Systems with Collaborative Base Station

    Directory of Open Access Journals (Sweden)

    Xingwang Li

    2014-01-01

    Full Text Available Massive MIMO have drawn considerable attention as they enable significant capacity and coverage improvement in wireless cellular network. However, pilot contamination is a great challenge in massive MIMO systems. Under this circumstance, cooperation and three-dimensional (3D MIMO are emerging technologies to eliminate the pilot contamination and to enhance the performance relative to the traditional interference-limited implementations. Motivated by this, we investigate the achievable sum rate performance of MIMO systems in the uplink employing cooperative base station (BS and 3D MIMO systems. In our model, we consider the effects of both large-scale and small-scale fading, as well as the spatial correlation and indoor-to-outdoor high-rise propagation environment. In particular, we investigate the cooperative communication model based on 3D MIMO and propose a closed-form lower bound on the sum rate. Utilizing this bound, we pursue a “large-system” analysis and provide the asymptotic expression when the number of antennas at the BS grows large, and when the numbers of antennas at transceiver grow large with a fixed ratio. We demonstrate that the lower bound is very tight and becomes exact in the massive MIMO system limits. Finally, under the sum rate maximization condition, we derive the optimal number of UTs to be served.

  3. Cooperative Game Study of Airlines Based on Flight Frequency Optimization

    Directory of Open Access Journals (Sweden)

    Wanming Liu

    2014-01-01

    Full Text Available By applying the game theory, the relationship between airline ticket price and optimal flight frequency is analyzed. The paper establishes the payoff matrix of the flight frequency in noncooperation scenario and flight frequency optimization model in cooperation scenario. The airline alliance profit distribution is converted into profit distribution game based on the cooperation game theory. The profit distribution game is proved to be convex, and there exists an optimal distribution strategy. The results show that joining the airline alliance can increase airline whole profit, the change of negotiated prices and cost is beneficial to profit distribution of large airlines, and the distribution result is in accordance with aviation development.

  4. Project-Based Learning in Geotechnics: Cooperative versus Collaborative Teamwork

    Science.gov (United States)

    Pinho-Lopes, Margarida; Macedo, Joaquim

    2016-01-01

    Since 2007/2008 project-based learning models have been used to deliver two fundamental courses on Geotechnics in University of Aveiro, Portugal. These models have evolved and have encompassed either cooperative or collaborative teamwork. Using data collected in five editions of each course (Soil Mechanics I and Soil Mechanics II), the different…

  5. Project-Based Learning in Geotechnics: Cooperative versus Collaborative Teamwork

    Science.gov (United States)

    Pinho-Lopes, Margarida; Macedo, Joaquim

    2016-01-01

    Since 2007/2008 project-based learning models have been used to deliver two fundamental courses on Geotechnics in University of Aveiro, Portugal. These models have evolved and have encompassed either cooperative or collaborative teamwork. Using data collected in five editions of each course (Soil Mechanics I and Soil Mechanics II), the different…

  6. Enhancing base station connectivity with directional information of movement

    Directory of Open Access Journals (Sweden)

    Eugene Kim

    2016-09-01

    Full Text Available High-performance smartphones with various sensor capabilities, including the inertial measurement unit, allow us to have higher freedom to localize our movements and utilize them for other applications. In this paper, we present a simple method to estimate the heading of a user using only a digital compass, accelerometer, and gyroscope. Several experiments were conducted using an Apple iPhone. In addition, we also present an algorithm to reduce the number of handover attempts in a dense base station environment. A series of simulations were conducted on OPNET in various emulated environments to present the effectiveness of the proposed method. The simulation results show that our proposed algorithm effectively reduces the ping-pong effect in a dense base station environment.

  7. Base Station Antenna Pattern Distortion in Practical Urban Deployment Scenarios

    DEFF Research Database (Denmark)

    Rodriguez Larrad, Ignacio; Nguyen, Huan Cong; Sørensen, Troels Bundgaard

    2014-01-01

    In real urban deployments, base station antennas are typically not placed in free space conditions. Therefore, the radiation pattern can be affected by mounting structures and nearby obstacles located in the proximity of the antenna (near-field), which are often not taken into consideration. Also...... the intrinsic propagation mechanisms of the urban environment (far-field) can contribute to the distortion of the radiation pattern observed in a practical deployment scenario, especially when comparing it to the antenna pattern provided by the manufacturer and typically measured in free space. This paper...... presents a combination of near-field and far-field simulations aimed to provide an overview of the distortion experienced by the base station antenna pattern in two different urban deployment scenarios: rooftop and telecommunications tower. The study illustrates how, in comparison with the near...

  8. Theodolite-camera videometrics system based on total station

    Science.gov (United States)

    Zhu, Zhao-kun; Yuan, Yun; Zhang, Xiao-hu

    2011-08-01

    A novel measuring system, named Theodolite-camera Videometrics System (TVS) based on total station, has been introduced in this paper, and the concept of theodolite-camera which is the key component of TVS has been proposed, it consists of non-metric camera and rotation platform generally, and can rotate horizontally and vertically. TVS based on total station is free of field control points, and the fields of view of its theodolite-cameras are nonfixed, thus TVS is qualified for targets with wide moving range or big structure. Theodolite-camera model has been analyzed and presented in detail in this paper. The calibration strategy adopted has been demonstrated to be accurate and feasible by both simulated and real data, and TVS has also been proved to be a valid, reliable, precise measuring system, and living up to expectations.

  9. Greening radio access networks using distributed base station architectures

    DEFF Research Database (Denmark)

    Kardaras, Georgios; Soler, José; Dittmann, Lars

    2010-01-01

    . However besides this, increasing energy efficiency represents a key factor for reducing operating expenses and deploying cost effective mobile networks. This paper presents how distributed base station architectures can contribute in greening radio access networks. More specifically, the advantages...... of introducing remote radio head modules are discussed. Substantial flexibility is provided in terms of power consumption, as a result of combining efficient hardware with intelligent software. Additionally, it is underlined that designing eco-sustainable systems needs to follow a holistic approach towards...

  10. Dual-reflector omnidirectional antenna for MMDS base stations

    OpenAIRE

    Kim, Oleksiy S.

    1999-01-01

    Multichannel Multipoint Distribution System (MMDS) along with cable net represent the most convenient way to distribute TV and radio signals over a small area. Asynchronous access to the Inter-net can also be realized via MMDS. MMDS base-stations, covering a circle area, employ antennas, that produce omnidirectional radiation patterns in the azimuth plane. Common methods of achieving a uniform azimuth distribution are using arrays of surface slots on a circular or coaxial waveguide, arrays of...

  11. Evolving technologies for Space Station Freedom computer-based workstations

    Science.gov (United States)

    Jensen, Dean G.; Rudisill, Marianne

    1990-01-01

    Viewgraphs on evolving technologies for Space Station Freedom computer-based workstations are presented. The human-computer computer software environment modules are described. The following topics are addressed: command and control workstation concept; cupola workstation concept; Japanese experiment module RMS workstation concept; remote devices controlled from workstations; orbital maneuvering vehicle free flyer; remote manipulator system; Japanese experiment module exposed facility; Japanese experiment module small fine arm; flight telerobotic servicer; human-computer interaction; and workstation/robotics related activities.

  12. Measurements of Electromagnetic Fields Emitted from Cellular Base Stations in

    Directory of Open Access Journals (Sweden)

    K. J. Ali

    2013-05-01

    Full Text Available With increasing the usage of mobile communication devices and internet network information, the entry of private telecommunications companies in Iraq has been started since 2003. These companies began to build up cellular towers to accomplish the telecommunication works but they ignore the safety conditions imposed for the health and environment that are considered in random way. These negative health effects which may cause a health risk for life beings and environment pollution. The aim of this work is to determine the safe and unsafe ranges and discuss damage caused by radiation emitted from Asia cell base stations in Shirqat city and discuses the best ways in which can be minimize its exposure level to avoid its negative health effects. Practical measurements of power density around base stations has been accomplished by using a radiation survey meter type (Radio frequency EMF Strength Meter 480846 in two ways. The first way of measurements has been accomplished at a height of 2 meters above ground for different distances from (0-300 meters .The second way is at a distance of 150 meters for different levels from (2-15 meters above ground level. The maximum measured power density is about (3 mW/m2. Results indicate that the levels of power density are far below the RF radiation exposure of USSR safety standards levels. And that means these cellular base station don't cause negative the health effect for life being if the exposure is within the acceptable international standard levels.

  13. Cooperative Sequential Spectrum Sensing Based on Level-triggered Sampling

    CERN Document Server

    Yilmaz, Yasin; Wang, Xiaodong

    2011-01-01

    We propose a new framework for cooperative spectrum sensing in cognitive radio networks, that is based on a novel class of non-uniform samplers, called the event-triggered samplers, and sequential detection. In the proposed scheme, each secondary user computes its local sensing decision statistic based on its own channel output; and whenever such decision statistic crosses certain predefined threshold values, the secondary user will send one (or several) bit of information to the fusion center. The fusion center asynchronously receives the bits from different secondary users and updates the global sensing decision statistic to perform a sequential probability ratio test (SPRT), to reach a sensing decision. We provide an asymptotic analysis for the above scheme, and under different conditions, we compare it against the cooperative sensing scheme that is based on traditional uniform sampling and sequential detection. Simulation results show that the proposed scheme, using even 1 bit, can outperform its uniform ...

  14. Criminal Investigation EIDSS Based on Cooperative Mapping Mechanism

    Directory of Open Access Journals (Sweden)

    Ping He

    2014-10-01

    Full Text Available On purpose of improving the research in extension intelligence systems when the knowledge in hand is not sufficient, an intuition evidence model (IEM based on human-computer cooperative is presented. From the initial intuition process space defined by the primitive experience, a series of interactive mapping learning systems (IMLS with various reductive levels are created. For, each IELS, the rule sets with respective belief degree are induced and saved. The paper introduces cooperative mapping of intuition evidence and object hypothesesmethod to the criminal investigation, and poses a skeleton of cooperative reasoning. The paper views that the reliability of the cooperative reasoning depends on the human-computer interaction results. Simultaneously, choosing the case-cracking clue should be determined by comprehensive evaluations and self-learning of intuition-formal judgments are essentially needed. When applying the model to reasoning and decision making, one can match the intuition judge of the given object to the rule sets of relative nodes, and then draw the conclusion by using some kind of evaluation algorithm. A simple example on how to create and apply the model is give.

  15. Optimising base station location for UMTS cellular networks

    Science.gov (United States)

    Kalata, G.; Pozniak-Koszalka, I.; Koszalka, L.; Kasprzak, A.

    2014-12-01

    Rapid development of universal mobile telecommunication systems put demands on tools for assisting planning of cellular network infrastructure. The tools need to focus on critical issues in modern cellular networks and techniques used for previous generation system no longer serve useful. In this paper, an algorithm based on Branch & Bound approach is proposed for solving base station location problem, covering interference levels, traffic demands and power control mechanism. The efficiency of the algorithm is evaluated with respect to existing approaches for solving this problem - using the designed and implemented experimentation system.

  16. Project-based learning in Geotechnics: cooperative versus collaborative teamwork

    Science.gov (United States)

    Pinho-Lopes, Margarida; Macedo, Joaquim

    2016-01-01

    Since 2007/2008 project-based learning models have been used to deliver two fundamental courses on Geotechnics in University of Aveiro, Portugal. These models have evolved and have encompassed either cooperative or collaborative teamwork. Using data collected in five editions of each course (Soil Mechanics I and Soil Mechanics II), the different characteristics of the models using cooperative or collaborative teamwork are pointed out and analysed, namely in terms of the students' perceptions. The data collected include informal feedback from students, monitoring of their marks and academic performance, and answers to two sets of questionnaires: developed for these courses, and institutional. The data indicate students have good opinion of the project-based learning model, though collaborative teamwork is the best rated. The overall efficacy of the models was analysed (sum of their effectiveness, efficiency and attractiveness). The collaborative model was found more adequate.

  17. Feature selection with neighborhood entropy-based cooperative game theory.

    Science.gov (United States)

    Zeng, Kai; She, Kun; Niu, Xinzheng

    2014-01-01

    Feature selection plays an important role in machine learning and data mining. In recent years, various feature measurements have been proposed to select significant features from high-dimensional datasets. However, most traditional feature selection methods will ignore some features which have strong classification ability as a group but are weak as individuals. To deal with this problem, we redefine the redundancy, interdependence, and independence of features by using neighborhood entropy. Then the neighborhood entropy-based feature contribution is proposed under the framework of cooperative game. The evaluative criteria of features can be formalized as the product of contribution and other classical feature measures. Finally, the proposed method is tested on several UCI datasets. The results show that neighborhood entropy-based cooperative game theory model (NECGT) yield better performance than classical ones.

  18. Cooperative coalition for formation flight scheduling based on incomplete information

    Directory of Open Access Journals (Sweden)

    Meng Linghang

    2015-12-01

    Full Text Available This study analyzes the cooperative coalition problem for formation scheduling based on incomplete information. A multi-agent cooperative coalition framework is developed to optimize the formation scheduling problem in a decentralized manner. The social class differentiation mechanism and role-assuming mechanism are incorporated into the framework, which, in turn, ensures that the multi-agent system (MAS evolves in the optimal direction. Moreover, a further differentiation pressure can be achieved to help MAS escape from local optima. A Bayesian coalition negotiation algorithm is constructed, within which the Harsanyi transformation is introduced to transform the coalition problem based on incomplete information to the Bayesian-equivalent coalition problem based on imperfect information. The simulation results suggest that the distribution of agents’ expectations of other agents’ unknown information approximates to the true distribution after a finite set of generations. The comparisons indicate that the MAS cooperative coalition algorithm produces a significantly better utility and possesses a more effective capability of escaping from local optima than the proposal-engaged marriage algorithm and the Simulated Annealing algorithm.

  19. Cooperative coalition for formation flight scheduling based on incomplete information

    Institute of Scientific and Technical Information of China (English)

    Meng Linghang; Xu Xiaohao; Zhao Yifei

    2015-01-01

    This study analyzes the cooperative coalition problem for formation scheduling based on incomplete information. A multi-agent cooperative coalition framework is developed to optimize the formation scheduling problem in a decentralized manner. The social class differentiation mech-anism and role-assuming mechanism are incorporated into the framework, which, in turn, ensures that the multi-agent system (MAS) evolves in the optimal direction. Moreover, a further differen-tiation pressure can be achieved to help MAS escape from local optima. A Bayesian coalition nego-tiation algorithm is constructed, within which the Harsanyi transformation is introduced to transform the coalition problem based on incomplete information to the Bayesian-equivalent coali-tion problem based on imperfect information. The simulation results suggest that the distribution of agents’ expectations of other agents’ unknown information approximates to the true distribution after a finite set of generations. The comparisons indicate that the MAS cooperative coalition algo-rithm produces a significantly better utility and possesses a more effective capability of escaping from local optima than the proposal-engaged marriage algorithm and the Simulated Annealing algorithm.

  20. Applicability of an exposure model for the determination of emissions from mobile phone base stations

    DEFF Research Database (Denmark)

    Breckenkamp, J; Neitzke, H P; Bornkessel, C

    2008-01-01

    Applicability of a model to estimate radiofrequency electromagnetic field (RF-EMF) strength in households from mobile phone base stations was evaluated with technical data of mobile phone base stations available from the German Net Agency, and dosimetric measurements, performed...

  1. Cooperative peer-to-peer multiagent-based systems.

    Science.gov (United States)

    Caram, L F; Caiafa, C F; Ausloos, M; Proto, A N

    2015-08-01

    A multiagent based model for a system of cooperative agents aiming at growth is proposed. This is based on a set of generalized Verhulst-Lotka-Volterra differential equations. In this study, strong cooperation is allowed among agents having similar sizes, and weak cooperation if agents have markedly different "sizes", thus establishing a peer-to-peer modulated interaction scheme. A rigorous analysis of the stable configurations is presented first examining the fixed points of the system, next determining their stability as a function of the model parameters. It is found that the agents are self-organizing into clusters. Furthermore, it is demonstrated that, depending on parameter values, multiple stable configurations can coexist. It occurs that only one of them always emerges with probability close to one, because its associated attractor dominates over the rest. This is shown through numerical integrations and simulations, after analytic developments. In contrast to the competitive case, agents are able to increase their capacity beyond the no-interaction case limit. In other words, when some collaborative partnership among a relatively small number of partners takes place, all agents act in good faith prioritizing the common good, when receiving a mutual benefit allowing them to surpass their capacity.

  2. Cooperative peer-to-peer multiagent-based systems

    Science.gov (United States)

    Caram, L. F.; Caiafa, C. F.; Ausloos, M.; Proto, A. N.

    2015-08-01

    A multiagent based model for a system of cooperative agents aiming at growth is proposed. This is based on a set of generalized Verhulst-Lotka-Volterra differential equations. In this study, strong cooperation is allowed among agents having similar sizes, and weak cooperation if agents have markedly different "sizes", thus establishing a peer-to-peer modulated interaction scheme. A rigorous analysis of the stable configurations is presented first examining the fixed points of the system, next determining their stability as a function of the model parameters. It is found that the agents are self-organizing into clusters. Furthermore, it is demonstrated that, depending on parameter values, multiple stable configurations can coexist. It occurs that only one of them always emerges with probability close to one, because its associated attractor dominates over the rest. This is shown through numerical integrations and simulations, after analytic developments. In contrast to the competitive case, agents are able to increase their capacity beyond the no-interaction case limit. In other words, when some collaborative partnership among a relatively small number of partners takes place, all agents act in good faith prioritizing the common good, when receiving a mutual benefit allowing them to surpass their capacity.

  3. Cooperative Opportunistic Pressure Based Routing for Underwater Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Nadeem Javaid

    2017-03-01

    Full Text Available In this paper, three opportunistic pressure based routing techniques for underwater wireless sensor networks (UWSNs are proposed. The first one is the cooperative opportunistic pressure based routing protocol (Co-Hydrocast, second technique is the improved Hydrocast (improved-Hydrocast, and third one is the cooperative improved Hydrocast (Co-improved Hydrocast. In order to minimize lengthy routing paths between the source and the destination and to avoid void holes at the sparse networks, sensor nodes are deployed at different strategic locations. The deployment of sensor nodes at strategic locations assure the maximum monitoring of the network field. To conserve the energy consumption and minimize the number of hops, greedy algorithm is used to transmit data packets from the source to the destination. Moreover, the opportunistic routing is also exploited to avoid void regions by making backward transmissions to find reliable path towards the destination in the network. The relay cooperation mechanism is used for reliable data packet delivery, when signal to noise ratio (SNR of the received signal is not within the predefined threshold then the maximal ratio combining (MRC is used as a diversity technique to improve the SNR of the received signals at the destination. Extensive simulations validate that our schemes perform better in terms of packet delivery ratio and energy consumption than the existing technique; Hydrocast.

  4. Cooperative Opportunistic Pressure Based Routing for Underwater Wireless Sensor Networks.

    Science.gov (United States)

    Javaid, Nadeem; Muhammad; Sher, Arshad; Abdul, Wadood; Niaz, Iftikhar Azim; Almogren, Ahmad; Alamri, Atif

    2017-03-19

    In this paper, three opportunistic pressure based routing techniques for underwater wireless sensor networks (UWSNs) are proposed. The first one is the cooperative opportunistic pressure based routing protocol (Co-Hydrocast), second technique is the improved Hydrocast (improved-Hydrocast), and third one is the cooperative improved Hydrocast (Co-improved Hydrocast). In order to minimize lengthy routing paths between the source and the destination and to avoid void holes at the sparse networks, sensor nodes are deployed at different strategic locations. The deployment of sensor nodes at strategic locations assure the maximum monitoring of the network field. To conserve the energy consumption and minimize the number of hops, greedy algorithm is used to transmit data packets from the source to the destination. Moreover, the opportunistic routing is also exploited to avoid void regions by making backward transmissions to find reliable path towards the destination in the network. The relay cooperation mechanism is used for reliable data packet delivery, when signal to noise ratio (SNR) of the received signal is not within the predefined threshold then the maximal ratio combining (MRC) is used as a diversity technique to improve the SNR of the received signals at the destination. Extensive simulations validate that our schemes perform better in terms of packet delivery ratio and energy consumption than the existing technique; Hydrocast.

  5. Remote Sensing Image Feature Extracting Based Multiple Ant Colonies Cooperation

    Directory of Open Access Journals (Sweden)

    Zhang Zhi-long

    2014-02-01

    Full Text Available This paper presents a novel feature extraction method for remote sensing imagery based on the cooperation of multiple ant colonies. First, multiresolution expression of the input remote sensing imagery is created, and two different ant colonies are spread on different resolution images. The ant colony in the low-resolution image uses phase congruency as the inspiration information, whereas that in the high-resolution image uses gradient magnitude. The two ant colonies cooperate to detect features in the image by sharing the same pheromone matrix. Finally, the image features are extracted on the basis of the pheromone matrix threshold. Because a substantial amount of information in the input image is used as inspiration information of the ant colonies, the proposed method shows higher intelligence and acquires more complete and meaningful image features than those of other simple edge detectors.

  6. A Trust-Based Model for Security Cooperating in Vehicular Cloud Computing

    Directory of Open Access Journals (Sweden)

    Zhipeng Tang

    2016-01-01

    Full Text Available VCC is a computing paradigm which consists of vehicles cooperating with each other to realize a lot of practical applications, such as delivering packages. Security cooperation is a fundamental research topic in Vehicular Cloud Computing (VCC. Because of the existence of malicious vehicles, the security cooperation has become a challenging issue in VCC. In this paper, a trust-based model for security cooperating, named DBTEC, is proposed to promote vehicles’ security cooperation in VCC. DBTEC combines the indirect trust estimation in Public board and the direct trust estimation in Private board to compute the trust value of vehicles when choosing cooperative partners; a trustworthy cooperation path generating scheme is proposed to ensure the safety of cooperation and increase the cooperation completion rates in VCC. Extensive experiments show that our scheme improves the overall cooperation completion rates by 6~7%.

  7. Electromagnetic fields from mobile phone base station - variability analysis.

    Science.gov (United States)

    Bienkowski, Pawel; Zubrzak, Bartlomiej

    2015-09-01

    The article describes the character of electromagnetic field (EMF) in mobile phone base station (BS) surroundings and its variability in time with an emphasis on the measurement difficulties related to its pulse and multi-frequency nature. Work also presents long-term monitoring measurements performed recently in different locations in Poland - small city with dispersed building development and in major polish city - dense urban area. Authors tried to determine the trends in changing of EMF spectrum analyzing daily changes of measured EMF levels in those locations. Research was performed using selective electromagnetic meters and also EMF meter with spectrum analysis.

  8. Non-Coop Station History

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Station history documentation for stations outside the US Cooperative Observer network. Primarily National Weather Service stations assigned WBAN station IDs. Other...

  9. Cooperativity-based modeling of heterotypic DNA nanostructure assembly.

    Science.gov (United States)

    Shapiro, Anastasia; Hozeh, Avital; Girshevitz, Olga; Abu-Horowitz, Almogit; Bachelet, Ido

    2015-07-27

    DNA origami is a robust method for the fabrication of nanoscale 2D and 3D objects with complex features and geometries. The process of DNA origami folding has been recently studied, however quantitative understanding of it is still elusive. Here, we describe a systematic quantification of the assembly process of DNA nanostructures, focusing on the heterotypic DNA junction-in which arms are unequal-as their basic building block. Using bulk fluorescence studies we tracked this process and identified multiple levels of cooperativity from the arms in a single junction to neighboring junctions in a large DNA origami object, demonstrating that cooperativity is a central underlying mechanism in the process of DNA nanostructure assembly. We show that the assembly of junctions in which the arms are consecutively ordered is more efficient than junctions with randomly-ordered components, with the latter showing assembly through several alternative trajectories as a potential mechanism explaining the lower efficiency. This highlights consecutiveness as a new design consideration that could be implemented in DNA nanotechnology CAD tools to produce more efficient and high-yield designs. Altogether, our experimental findings allowed us to devise a quantitative, cooperativity-based heuristic model for the assembly of DNA nanostructures, which is highly consistent with experimental observations.

  10. Securing Localization With Hidden and Mobile Base Stations

    DEFF Research Database (Denmark)

    Capkun, Srdjan; Srivastava, Mani; Cagalj, Mario

    2006-01-01

    Until recently, the problem of localization in wireless networks has been mainly studied in a nonadversarial setting. Only recently, a number of solutions have been proposed that aim to detect and prevent attacks on localization systems. In this work, we propose a new approach to secure...... localization based on hidden and mobile base stations. Our approach enables secure localization with a broad spectrum of localization techniques: ultrasonic or radio, based on received signal strength or signal time of flight. Through several examples we show how this approach can be used to secure nodecentric...... and infrastructure-centric localization schemes. We further show how this approach can be applied to secure localization in sensor networks....

  11. Charging stations location model based on spatiotemporal electromobility use patterns

    Science.gov (United States)

    Pagany, Raphaela; Marquardt, Anna; Zink, Roland

    2016-04-01

    One of the major challenges for mainstream adoption of electric vehicles is the provision of infrastructure for charging the batteries of the vehicles. The charging stations must not only be located dense enough to allow users to complete their journeys, but the electric energy must also be provided from renewable sources in order to truly offer a transportation with less CO2 emissions. The examination of potential locations for the charging of electric vehicles can facilitate the adaption of electromobility and the integration of electronic vehicles in everyday life. A geographic information system (GIS) based model for optimal location of charging stations in a small and regional scale is presented. This considers parameters such as the forecast of electric vehicle use penetration, the relevant weight of diverse point of interests and the distance between parking area and destination for different vehicle users. In addition to the spatial scale the temporal modelling of the energy demand at the different charging locations has to be considerate. Depending on different user profiles (commuters, short haul drivers etc.) the frequency of charging vary during the day, the week and the year. In consequence, the spatiotemporal variability is a challenge for a reliable energy supply inside a decentralized renewable energy system. The presented model delivers on the one side the most adequate identified locations for charging stations and on the other side the interaction between energy supply and demand for electromobility under the consideration of temporal aspects. Using ESRI ArcGIS Desktop, first results for the case study region of Lower Bavaria are generated. The aim of the concept is to keep the model transferable to other regions and also open to integrate further and more detailed user profiles, derived from social studies about i.e. the daily behavior and the perception of electromobility in a next step.

  12. Monitoring and optimization of energy consumption of base transceiver stations

    CERN Document Server

    Spagnuolo, Antonio; Vetromile, Carmela; Formosi, Roberto; Lubritto, Carmine

    2015-01-01

    The growth and development of the mobile phone network has led to an increased demand for energy by the telecommunications sector, with a noticeable impact on the environment. Monitoring of energy consumption is a great tool for understanding how to better manage this consumption and find the best strategy to adopt in order to maximize reduction of unnecessary usage of electricity. This paper reports on a monitoring campaign performed on six Base Transceiver Stations (BSs) located central Italy, with different technology, typology and technical characteristics. The study focuses on monitoring energy consumption and environmental parameters (temperature, noise, and global radiation), linking energy consumption with the load of telephone traffic and with the air conditioning functions used to cool the transmission equipment. Moreover, using experimental data collected, it is shown, with a Monte Carlo simulation based on power saving features, how the BS monitored could save energy.

  13. Game theoretic analysis for pricing-based incentive mechanism in non-dedicated cooperative relay networks

    Institute of Scientific and Technical Information of China (English)

    张闯; 赵洪林; 贾敏

    2015-01-01

    In non-dedicated cooperative relay networks, each node is autonomous and selfish in nature, and thus spontaneous cooperation among nodes is challenged. To stimulate the selfish node to participate in cooperation, a pricing-based cooperation engine using game theory was designed. Firstly, the feasible regions of the charge price and reimbursement price were deduced. Then, the non-cooperative and cooperative games were adopted to analyze the amount of bandwidth that initiating cooperation node (ICN) forwards data through participating cooperation node (PCN) and the amount of bandwidth that PCN helps ICN to relay data. Meanwhile, the Nash equilibrium solutions of cooperation bandwidth allocations (CBAs) were obtained through geometrical interpretation. Secondly, a pricing-based cooperation engine was proposed and a cooperative communication system model with cooperation engines was depicted. Finally, an algorithm based on game theory was proposed to realize the cooperation engine. The simulation results demonstrate that, compared with the system without pricing-based incentive, the proposed system can significantly improve the ICN’s metric measured by bit-per-Joule and increase the PCN’s revenue.

  14. Virtual Induction Loops Based on Cooperative Vehicular Communications

    Directory of Open Access Journals (Sweden)

    Maria Calderon

    2013-01-01

    Full Text Available Induction loop detectors have become the most utilized sensors in traffic management systems. The gathered traffic data is used to improve traffic efficiency (i.e., warning users about congested areas or planning new infrastructures. Despite their usefulness, their deployment and maintenance costs are expensive. Vehicular networks are an emerging technology that can support novel strategies for ubiquitous and more cost-effective traffic data gathering. In this article, we propose and evaluate VIL (Virtual Induction Loop, a simple and lightweight traffic monitoring system based on cooperative vehicular communications. The proposed solution has been experimentally evaluated through simulation using real vehicular traces.

  15. Time of arrival based location estimation for cooperative relay networks

    KAUST Repository

    Çelebi, Hasari Burak

    2010-09-01

    In this paper, we investigate the performance of a cooperative relay network performing location estimation through time of arrival (TOA). We derive Cramer-Rao lower bound (CRLB) for the location estimates using the relay network. The analysis is extended to obtain average CRLB considering the signal fluctuations in both relay and direct links. The effects of the channel fading of both relay and direct links and amplification factor and location of the relay node on average CRLB are investigated. Simulation results show that the channel fading of both relay and direct links and amplification factor and location of relay node affect the accuracy of TOA based location estimation. ©2010 IEEE.

  16. Development of automated microrobot-based nanohandling stations for nanocharacterization

    Science.gov (United States)

    Fatikow, Sergej; Eichhorn, Volkmar; Krohs, Florian; Mircea, Iulian; Stolle, Christian; Hagemann, Saskia

    2007-05-01

    Current research work on the development of automated microrobot-based nanohandling stations (AMNSs) using the probe of an atomic force microscope (AFM) as an endeffector is presented. The manipulation of individual multiwalled carbon nanotubes (MWCNTs) and the characterization of eukaryotic cells are aspired applications. For this reason, the developed AMNSs have to be integrated both into a scanning electron microscope (SEM) for the nanomanipulation of carbon nanotubes (CNTs) and into an optical microscope for the cell characterization. Such an AMNS combines different micro- and nanomanipulators, each offering three degrees of freedom (DoF), in order to perform the coarse and fine positioning between object and endeffector. Piezoresistive AFM probes are applied as an endeffector allowing to measure the acting forces and to realize a force feedback for the station's control system. First investigations have been carried out by bending of MWCNTs and calculating the Young's modulus of a MWCNT. Electrically conductive adhesives (ECAs) have been developed for the microelectronics industry, and their mechanical properties have to be determined. Therefore an AMNS for the mechanical characterization of thin ECA coatings by nanoindentation inside an SEM is presented as well, showing first experimental results.

  17. Metric-Based Cooperative Routing in Multihop Ad Hoc Networks

    OpenAIRE

    Xin He; Frank Y. Li

    2012-01-01

    Cooperative communication fully leverages the broadcast nature of wireless channels and exploits time/spatial diversity in a distributed manner, thereby achieving significant improvements in system capacity and transmission reliability. Cooperative diversity has been well studied from the physical layer perspective. Thereafter, cooperative MAC design has also drawn much attention recently. However, very little work has addressed cooperation at the routing layer. In this paper, we propose a si...

  18. Greening radio access networks using distributed base station architectures

    DEFF Research Database (Denmark)

    Kardaras, Georgios; Soler, José; Dittmann, Lars

    2010-01-01

    Several actions for developing environmentally friendly technologies have been taken in most industrial fields. Significant resources have also been devoted in mobile communications industry. Moving towards eco-friendly alternatives is primarily a social responsibility for network operators....... However besides this, increasing energy efficiency represents a key factor for reducing operating expenses and deploying cost effective mobile networks. This paper presents how distributed base station architectures can contribute in greening radio access networks. More specifically, the advantages...... of introducing remote radio head modules are discussed. Substantial flexibility is provided in terms of power consumption, as a result of combining efficient hardware with intelligent software. Additionally, it is underlined that designing eco-sustainable systems needs to follow a holistic approach towards...

  19. Station-based Surface Data Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Q. [DOE ARM Climate Research Facility, Washington, DC (United States); Xie, S. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-07-01

    This report describes the Atmospheric Radiation Measurement (ARM) Best Estimate (ARMBE) station-based surface data (ARMBESTNS) value-added product. It is a twin data product of the ARMBE 2-Dimensional gridded (ARMBE2DGRID) data set. Unlike the ARMBE2DGRID data set, ARMBESTNS data are reported at the original site locations and show the original information (except for the interpolation over time). Therefore, the users have the flexibility to process the data with the approach more suitable for their applications. This document provides information about the input data, quality control (QC) method, and output format of this data set. As much of the information is identical to that of the ARMBE2DGRID data, this document will emphasize more on the different aspects of these two data sets.

  20. Energy Sharing Framework for Microgrid-Powered Cellular Base Stations

    KAUST Repository

    Farooq, Muhammad Junaid

    2017-02-07

    Cellular base stations (BSs) are increasingly becoming equipped with renewable energy generators to reduce operational expenditures and carbon footprint of wireless communications. Moreover, advancements in the traditional electricity grid allow two-way power flow and metering that enable the integration of distributed renewable energy generators at BS sites into a microgrid. In this paper, we develop an optimized energy management framework for microgrid-connected cellular BSs that are equipped with renewable energy generators and finite battery storage to minimize energy cost. The BSs share excess renewable energy with others to reduce the dependency on the conventional electricity grid. Three cases are investigated where the renewable energy generation is unknown, perfectly known, and partially known ahead of time. For the partially known case where only the statistics of renewable energy generation are available, stochastic programming is used to achieve a conservative solution. Results show the time varying energy management behaviour of the BSs and the effect of energy sharing between them.

  1. The Bus Station Spacing Optimization Based on Game Theory

    Directory of Open Access Journals (Sweden)

    Changjiang Zheng

    2015-01-01

    Full Text Available With the development of city, the problem of traffic is becoming more and more serious. Developing public transportation has become the key to solving this problem in all countries. Based on the existing public transit network, how to improve the bus operation efficiency, and reduce the residents transit trip cost has become a simple and effective way to develop the public transportation. Bus stop spacing is an important factor affecting passengers’ travel time. How to set up bus stop spacing has become the key to reducing passengers’ travel time. According to comprehensive traffic survey, theoretical analysis, and summary of urban public transport characteristics, this paper analyzes the impact of bus stop spacing on passenger in-bus time cost and out-bus time cost and establishes in-bus time and out-bus time model. Finally, the paper gets the balance best station spacing by introducing the game theory.

  2. Cooperative Learning: Improving University Instruction by Basing Practice on Validated Theory

    Science.gov (United States)

    Johnson, David W.; Johnson, Roger T.; Smith, Karl A.

    2014-01-01

    Cooperative learning is an example of how theory validated by research may be applied to instructional practice. The major theoretical base for cooperative learning is social interdependence theory. It provides clear definitions of cooperative, competitive, and individualistic learning. Hundreds of research studies have validated its basic…

  3. Cooperative Learning: Improving University Instruction by Basing Practice on Validated Theory

    Science.gov (United States)

    Johnson, David W.; Johnson, Roger T.; Smith, Karl A.

    2014-01-01

    Cooperative learning is an example of how theory validated by research may be applied to instructional practice. The major theoretical base for cooperative learning is social interdependence theory. It provides clear definitions of cooperative, competitive, and individualistic learning. Hundreds of research studies have validated its basic…

  4. Railway Station Facilities in Rural and Urban Services Based on Observation and User Feedback

    Directory of Open Access Journals (Sweden)

    Mohd Masirin Mohd Idrus

    2016-01-01

    Full Text Available Public transport is one of the facilities available in Malaysia. Overwhelming demand from the community has demanded public transport as an alternative for some people to do their daily activities. The increasing of Malaysian population brought many problems to the environment especially traffic congestion problem. The Government spends a lot of money to overcome this problem [10]. Public transport has been upgraded to ensure user comfort. Most people in the city are more interested in using railway transport as traffic congestion and travel time accuracy is better than other public transport [1, 5]. To influence public demand, the facilities available at the train station should be complete [3, 5]. The choice of location for the study are Batu Gajah station (station 1 and Kluang station (station 2 for rural services while Bandar Tasik Selatan station (station 3 and KL Central station (station 4 for urban services. The results of this study showed that, based on data and information obtained from field survey work and the feedback questionnaires from users, basic facilities at railway stations surveyed for urban and rural services can be identified and listed. An analysis of the status of the facilities at railway stations can be established through the safety of passengers and observations in the field. The facilities available at the urban service station are more complete than in rural service station. Facilities at railway station should be improved to attract people using the facilities.

  5. Robustness of cooperation in memory-based prisoner’s dilemma game on a square lattice

    Science.gov (United States)

    Ren, Guangming; Wang, Xingyuan

    2014-08-01

    Cooperation in prisoner’s dilemma game can be promoted significantly by introducing memory effects. In this work, we assume that the changing probability of strategy is determined by the agents’ accumulative payoff in all time steps. We have numerically investigated robustness of cooperation by introducing an attack probability, with which an individual in cooperation clusters becomes a defector. It is found that the density of cooperators at stable states decreases with the attack probability in traditional memoryless models. However, in the memory-based model, the density of cooperators cannot reach a stable state even if the attack probability is very small. The more the increase of the attack probability, the faster the vanishment of the cooperators. Our work could be helpful to understand the emergence of cooperation in systems consisting of selfish individuals. It suggests a new method to study whether cooperation can be maintained in noisy environments.

  6. Data communications method for mobile network in fourth generation communications system, involves delivering decoded data to mobile station from relay station, where mobile station receives data from both relay and base stations

    DEFF Research Database (Denmark)

    2008-01-01

    The method involves utilizing a base station (BS) (100) to transmit data to a relay station (RS) (110) and a mobile station (MS) (120), where the data includes two messages. The BS is utilized to transmit the two messages by utilizing a linear combination method, and the data is received in the RS...... and decoded. The decoded data is delivered to the MS from the RS, where the RS transmits the decoded data by utilizing another linear combination method. The MS receives data from both the BS and the RS....

  7. Measurements and Modelling of Base Station Power Consumption under Real Traffic Loads

    Directory of Open Access Journals (Sweden)

    Goran Petrovic

    2012-03-01

    Full Text Available Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications and UMTS (Universal Mobile Telecommunications System base stations according to their respective traffic load. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a fully operated base station site. Measurements show the existence of a direct relationship between base station traffic load and power consumption. According to this relationship, we develop a linear power consumption model for base stations of both technologies. This paper also gives an overview of the most important concepts which are being proposed to make cellular networks more energy-efficient.

  8. Deep Space Habitat Configurations Based On International Space Station Systems

    Science.gov (United States)

    Smitherman, David; Russell, Tiffany; Baysinger, Mike; Capizzo, Pete; Fabisinski, Leo; Griffin, Brand; Hornsby, Linda; Maples,Dauphne; Miernik, Janie

    2012-01-01

    A Deep Space Habitat (DSH) is the crew habitation module designed for long duration missions. Although humans have lived in space for many years, there has never been a habitat beyond low-Earth-orbit. As part of the Advanced Exploration Systems (AES) Habitation Project, a study was conducted to develop weightless habitat configurations using systems based on International Space Station (ISS) designs. Two mission sizes are described for a 4-crew 60-day mission, and a 4-crew 500-day mission using standard Node, Lab, and Multi-Purpose Logistics Module (MPLM) sized elements, and ISS derived habitation systems. These durations were selected to explore the lower and upper bound for the exploration missions under consideration including a range of excursions within the Earth-Moon vicinity, near earth asteroids, and Mars orbit. Current methods for sizing the mass and volume for habitats are based on mathematical models that assume the construction of a new single volume habitat. In contrast to that approach, this study explored the use of ISS designs based on existing hardware where available and construction of new hardware based on ISS designs where appropriate. Findings included a very robust design that could be reused if the DSH were assembled and based at the ISS and a transportation system were provided for its return after each mission. Mass estimates were found to be higher than mathematical models due primarily to the use of multiple ISS modules instead of one new large module, but the maturity of the designs using flight qualified systems have potential for improved cost, schedule, and risk benefits.

  9. Reference Station Network Based RTK Systems-Concepts and Progress

    Institute of Scientific and Technical Information of China (English)

    C. Rizos; S. Han

    2003-01-01

    The limitation of single base "real-time kinematic"(RTK) techniques is the distance between base receiver and the rover receiver due to distance-dependent biases, namely orbit bias,ionosphere bias and troposphere bias. Techniques have been developed to overcome this distance dependence using a network of GPS reference stations spread over a wide geographic area. Because the measurement biases will be modelled and corrected for, the positioning accuracy will be almost independent of the inter-receiver distance.Since the mid-1990s investigators have been investigating the optimal means of processing reference receiver data, and then providing generally referred to as Network-RTK. In 1993 the International Association of Geodesy (IAG) established a Special Study Group on"Wide Area Modelling for Precise Satellite Positioning" . This paperfocusses on the progress made during the last few years in designing Network-RTK architectures and the associated data processing algorithms and issues. Although many university investigators have been researching the fundamental challenges in functional and stochastic modelling, currently there is only one commercially available Network-RTK product, the Trimble VRS. However, with the use of the Internet as the primary data communication link, it is predicted that various sites around the world, over the next few years.

  10. A Cooperative Network Intrusion detection Based on Fuzzy SVMs

    Directory of Open Access Journals (Sweden)

    Shaohua Teng

    2010-04-01

    Full Text Available There is a large number of noise in the data obtained from network, which deteriorates intrusion detection performance. To delete the noise data, data preprocessing is done before the construction of hyperplane in support vector machine (SVM. By introducing fuzzy theory into SVM, a new method is proposed for network intrusion detection.  Because the attack behavior is different for different network protocol, a different fuzzy membership function is formatted, such that for each class of protocol there is a SVM. To implement this approach, a fuzzy SVM-based cooperative network intrusion detection system with multi-agent architecture is presented. It is composed of three types of agents corresponding to TCP, UDP, and ICMP protocols, respectively. Simulation experiments are done by using KDD CUP 1999 data set, results show that the training time is significantly shortened, storage space requirement is reduced, and classification accuracy is improved.

  11. Efficient 3-D Placement of an Aerial Base Station in Next Generation Cellular Networks

    OpenAIRE

    Yaliniz, R. Irem Bor; El-Keyi, Amr; Yanikomeroglu, Halim

    2016-01-01

    Agility and resilience requirements of future cellular networks may not be fully satisfied by terrestrial base stations in cases of unexpected or temporary events. A promising solution is assisting the cellular network via low-altitude unmanned aerial vehicles equipped with base stations, i.e., drone-cells. Although drone-cells provide a quick deployment opportunity as aerial base stations, efficient placement becomes one of the key issues. In addition to mobility of the drone-cells in the ve...

  12. RESEARCH ON MODEL AND METHOD OF NETWORK-BASED COOPERATIVE COMMERCE CHAIN IN AUTOMOBOLE INDUSTRY

    Institute of Scientific and Technical Information of China (English)

    Xiong Li; Chen Zichen; Zhang Fei; Gu Xinjian

    2003-01-01

    Based on the analysis on the development of the cooperative commerce in automobile industry, the systematic model of the cooperative commerce chain in automobile industry is illustrated,the flow of agent-based NCCC (network-based cooperative commerce chain) system is described, and the method and NCCC system in automobile industry are developed, and so the correctness and the feasibility of the theory and the method are confirmed.

  13. ZTE Becomes Global Leader in CDMA Base Station Market with 33% Share

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    ZTE Corporation announced on November 3, 2011 that it has become the global leader in the CDMA base station market, with a 32.6 percent share in first half 2011. According to a recent IDC analytical report on the global CDMA market, ZTE has increased its shipments of CDMA base stations steadily in recent years. As of the end of first half of 2011, the company's shipment of base-stations had exceeded 320 thousand units, pushing it to the top spot in the global CDMA base station market.

  14. Study on the Cooperative E-commerce Model between Enterprises based on the Value Chain

    Institute of Scientific and Technical Information of China (English)

    XU Jun[1,2; LIU Xiaoxing[1

    2015-01-01

    The real e-commerce between enterprises is based on the internal departments of enterprises and the cooperative interaction between enterprise and its partners. In this paper, on the basis of the theory of value chain, 11 cooperative e-commerce models between enterprises have been classified according to the activities of the cooperation between enterprises, and then every cooperative e-commerce model between enterprises is discussed. In practice, cooperative e-commerce between enterprises can be a combination of one or more e-commerce models between enterprises.

  15. Partner choice promotes cooperation: the two faces of testing with agent-based models.

    Science.gov (United States)

    Campennì, Marco; Schino, Gabriele

    2014-03-07

    Reciprocity is one of the most debated among the mechanisms that have been proposed to explain the evolution of cooperation. While a distinction can be made between two general processes that can underlie reciprocation (within-pair temporal relations between cooperative events, and partner choice based on benefits received), theoretical modelling has concentrated on the former, while the latter has been often neglected. We developed a set of agent-based models in which agents adopted a strategy of obligate cooperation and partner choice based on benefits received. Our models tested the ability of partner choice both to reproduce significant emergent features of cooperation in group living animals and to promote the evolution of cooperation. Populations formed by agents adopting a strategy of obligate cooperation and partner choice based on benefits received showed differentiated "social relationships" and a positive correlation between cooperation given and received, two common phenomena in animal cooperation. When selection across multiple generations was added to the model, agents adopting a strategy of partner choice based on benefits received outperformed selfish agents that did not cooperate. Our results suggest partner choice is a significant aspect of cooperation and provides a possible mechanism for its evolution.

  16. Coexistence of 3G repeaters with LTE base stations.

    Science.gov (United States)

    Yeo, Woon-Young; Lee, Sang-Min; Hwang, Gyung-Ho; Kim, Jae-Hoon

    2013-01-01

    Repeaters have been an attractive solution for mobile operators to upgrade their wireless networks at low cost and to extend network coverage effectively. Since the first LTE commercial deployment in 2009, many mobile operators have launched LTE networks by upgrading their 3G and legacy networks. Because all 3G frequency bands are shared with the frequency bands for LTE deployment and 3G mobile operators have an enormous number of repeaters, reusing 3G repeaters in LTE networks is definitely a practical and cost-efficient solution. However, 3G repeaters usually do not support spatial multiplexing with multiple antennas, and thus it is difficult to reuse them directly in LTE networks. In order to support spatial multiplexing of LTE, the role of 3G repeaters should be replaced with small LTE base stations or MIMO-capable repeaters. In this paper, a repeater network is proposed to reuse 3G repeaters in LTE deployment while still supporting multilayer transmission of LTE. Interestingly, the proposed network has a higher cluster throughput than an LTE network with MIMO-capable repeaters.

  17. Radiation safety of handheld mobile phones and base stations

    Energy Technology Data Exchange (ETDEWEB)

    Jokela, K.; Leszczynski, D.; Paile, W.; Salomaa, S.; Puranen, L.; Hyysalo, P

    1999-01-01

    The recent expansion of personal telecommunications has led to a rapid increase in the exposure of people to the radio-frequency (RF) radiation. Although the mobile phones are low power devices, the antenna is so close to the head that the local exposure may slightly exceed 2 W/kg, the current exposure limit for the local specific absorption rate SAR for the general public. The increase in the temperature is, however, too small to have any physiological significance. On the basis of experiments with cell cultures it is possible that other biological effects caused by some unknown non-thermal mechanism exist, but thus far there is no conclusive biological or epidemiological evidence to suggest any diseases or adverse physiological changes below the thermal threshold. The use of a mobile phone by a person wearing a pace-maker, is not recommended, if the immunity of the pace-maker has not been assured. The exposure caused by the base stations is in all practical cases well below the power density limits for general public. (author) 118 refs.

  18. Ohio's First Electrolysis-Based Hydrogen Fueling Station

    Science.gov (United States)

    Demattia, Brianne

    2014-01-01

    Presentation to the earth day coalition describing efforts with NASA GRC and Cleveland RTA on Ohio's hydrogen fueling station and bus demonstration. Project background and goals, challenges and successes, and current status.

  19. Role of delay-based reward in the spatial cooperation

    Science.gov (United States)

    Wang, Xu-Wen; Nie, Sen; Jiang, Luo-Luo; Wang, Bing-Hong; Chen, Shi-Ming

    2017-01-01

    Strategy selection in games, a typical decision making, usually brings noticeable reward for players which have discounted value if the delay appears. The discounted value is measure: earning sooner with a small reward or later with a delayed larger reward. Here, we investigate effects of delayed rewards on the cooperation in structured population. It is found that delayed reward supports the spreading of cooperation in square lattice, small-world and random networks. In particular, intermediate reward differences between delays impel the highest cooperation level. Interestingly, cooperative individuals with the same delay time steps form clusters to resist the invasion of defects, and cooperative individuals with lowest delay reward survive because they form the largest clusters in the lattice.

  20. Measurements of MIMO Indoor Channels at 1800 MHz with Multiple Indoor and Outdoor Base Stations

    Directory of Open Access Journals (Sweden)

    Jaldén Niklas

    2007-01-01

    Full Text Available This paper proposes several configurations for multiple base stations in indoor MIMO systems and compares their performance. The results are based on channel measurements realized with a MIMO testbed. The receiver was moved along several routes and floors on an office building. Both outdoor and indoor locations are considered for the transmitters or base stations, which allow the analysis of not only indoor but also outdoor-to-indoor environment. The use of 2 base stations with different system level combinations of the two is analyzed. We show that the configuration with base station selection provides almost as good performance as a full water-filling scheme when the 2 base stations are placed at different locations. Also the spatial correlation properties for the different configurations are analyzed and the importance of considering path loss when evaluating capacity is highlighted.

  1. Cooperative Traffic Control based on the Artificial Bee Colony

    Directory of Open Access Journals (Sweden)

    Jinjian Li

    2016-12-01

    Full Text Available This paper studies the traffic control problem in an isolated intersection without traffic lights and phase, because the right-of-way is distributed to each vehicle individually based on connection of the Vehicle-to-Infrastructure (V2I, and the compatible streams are dynamically combined according to the arrival vehicles in each traffic flows. The control objective in the proposed algorithm is to minimize the time delay, which is defined as the difference between the travel time in real state and that in free flow state. In order to realize this target, a cooperative control structure with a two-way communications is proposed. First of all, once the vehicle enters the communication zone, it sends its information to the intersection. Then the passing sequence is optimized in the intersection with the heuristic algorithm of the Artificial Bee Colony, based on the arrival interval of the vehicles. At last, each vehicle plans its speed profile to meet the received passing sequence by V2I. The simulation results show that each vehicle can finish the entire travel trip with a near free flow speed in the proposed method.

  2. A cooperative control algorithm for camera based observational systems.

    Energy Technology Data Exchange (ETDEWEB)

    Young, Joseph G.

    2012-01-01

    Over the last several years, there has been considerable growth in camera based observation systems for a variety of safety, scientific, and recreational applications. In order to improve the effectiveness of these systems, we frequently desire the ability to increase the number of observed objects, but solving this problem is not as simple as adding more cameras. Quite often, there are economic or physical restrictions that prevent us from adding additional cameras to the system. As a result, we require methods that coordinate the tracking of objects between multiple cameras in an optimal way. In order to accomplish this goal, we present a new cooperative control algorithm for a camera based observational system. Specifically, we present a receding horizon control where we model the underlying optimal control problem as a mixed integer linear program. The benefit of this design is that we can coordinate the actions between each camera while simultaneously respecting its kinematics. In addition, we further improve the quality of our solution by coupling our algorithm with a Kalman filter. Through this integration, we not only add a predictive component to our control, but we use the uncertainty estimates provided by the filter to encourage the system to periodically observe any outliers in the observed area. This combined approach allows us to intelligently observe the entire region of interest in an effective and thorough manner.

  3. Microcomputer-based coronary care unit central station.

    Science.gov (United States)

    De Lucia, F; Passariello, G; Villegas, G; Mora, F

    1990-01-01

    A four-bed central station that can be connected to any commercial intensive-care bedside monitor was developed. The system is based on a personal computer (IBM-AT compatible) as a local unit and on a microcontroller Intel 8031 as a remote unit. Four ECG signals are low-pass filtered, multiplexed, sampled at 256-Hz per channel, 8-bit A/D converted, preprocessed, and converted to a serial format RS-232 by the remote unit. The real-time display of the signals is at the standard speed of 25 and 50 mm/sec. Heartrate, alarms, trend plots, and general patient data are shown on an Olivetti M280 and EGA 13'' color monitor as the local unit. The communication speed was set at 57.6 Kbaud full duplex. Additionally, to reach standard monitoring sweep rates using a 13'' screen with 640 x 350 pixels, an ECG data-compression algorithm was implemented in the remote unit. This unit can support up to eight input channels and can work with any personal computer, via RS-232, with the appropriate software. It also allows other signal preprocessing software that could be developed, such as QRS detection or ST segment quantification, to be loaded into its random access memory and to be run under PC command. The development of this system demonstrated the use of a widespread piece of commercial equipment, the PC, in a very specific application, CCU monitoring, assuring low-cost system implementation. This feature is particularly attractive in upgrading existing CCU units in less developed countries.

  4. Method of sharing mobile unit state information between base station routers

    NARCIS (Netherlands)

    Bosch, Peter; Mullender, Sape J.; Polakos, Paul Anthony; Rajkumar, Ajay; Sundaram, Ganapathy S.

    2010-01-01

    The present invention provides a method of operating a first base station router. The method may include transmitting state information associated with at least one inactive mobile unit to at least one second base station router. The state information is usable to initiate an active session with the

  5. Method of sharing mobile unit state information between base station routers

    NARCIS (Netherlands)

    Bosch, Peter; Mullender, Sape J.; Polakos, Paul Anthony; Rajkumar, Ajay; Sundaram, Ganapathy S.

    2008-01-01

    The present invention provides a method of operating a first base station router. The method may include transmitting state information associated with at least one inactive mobile unit to at least one second base station router. The state information is usable to initiate an active session with the

  6. Method of sharing mobile unit state information between base station routers

    NARCIS (Netherlands)

    Bosch, H.G.P.; Mullender, Sape J.; Polakos, Paul Anthony; Rajkumar, Ajay; Sundaram, Ganapathy S.

    2007-01-01

    The present invention provides a method of operating a first base station router. The method may include transmitting state information associated with at least one inactive mobile unit to at least one second base station router. The state information is usable to initiate an active session with the

  7. Method of sharing mobile unit state information between base station routers

    NARCIS (Netherlands)

    Bosch, H.G.P.; Mullender, Sape J.; Polakos, Paul Anthony; Rajkumar, Ajay; Sundaram, Ganapathy S.

    2010-01-01

    The present invention provides a method of operating a first base station router. The method may include transmitting state information associated with at least one inactive mobile unit to at least one second base station router. The state information is usable to initiate an active session with the

  8. 47 CFR 90.656 - Responsibilities of base station licensees of Specialized Mobile Radio systems.

    Science.gov (United States)

    2010-10-01

    ... Specialized Mobile Radio systems. 90.656 Section 90.656 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Bands § 90.656 Responsibilities of base station licensees of Specialized Mobile Radio systems. (a) The licensees of base stations that provide Specialized Mobile Radio service on a commercial basis of the use...

  9. The Displacement of Base Station in Mobile Communication with Genetic Approach

    Directory of Open Access Journals (Sweden)

    Kim Nam

    2008-01-01

    Full Text Available Abstract This paper addresses the displacement of a base station with optimization approach. A genetic algorithm is used as optimization approach. A new representation that describes base station placement, transmitted power with real numbers, and new genetic operators is proposed and introduced. In addition, this new representation can describe the number of base stations. For the positioning of the base station, both coverage and economy efficiency factors were considered. Using the weighted objective function, it is possible to specify the location of the base station, the cell coverage, and its economy efficiency. The economy efficiency indicates a reduction in the number of base stations for cost effectiveness. To test the proposed algorithm, the proposed algorithm was applied to homogeneous traffic environment. Following this, the proposed algorithm was applied to an inhomogeneous traffic density environment in order to test it in actual conditions. The simulation results show that the algorithm enables the finding of a near optimal solution of base station placement, and it determines the efficient number of base stations. Moreover, it can offer a proper solution by adjusting the weighted objective function.

  10. The Displacement of Base Station in Mobile Communication with Genetic Approach

    Directory of Open Access Journals (Sweden)

    Nam Kim

    2008-05-01

    Full Text Available This paper addresses the displacement of a base station with optimization approach. A genetic algorithm is used as optimization approach. A new representation that describes base station placement, transmitted power with real numbers, and new genetic operators is proposed and introduced. In addition, this new representation can describe the number of base stations. For the positioning of the base station, both coverage and economy efficiency factors were considered. Using the weighted objective function, it is possible to specify the location of the base station, the cell coverage, and its economy efficiency. The economy efficiency indicates a reduction in the number of base stations for cost effectiveness. To test the proposed algorithm, the proposed algorithm was applied to homogeneous traffic environment. Following this, the proposed algorithm was applied to an inhomogeneous traffic density environment in order to test it in actual conditions. The simulation results show that the algorithm enables the finding of a near optimal solution of base station placement, and it determines the efficient number of base stations. Moreover, it can offer a proper solution by adjusting the weighted objective function.

  11. Analysis of Factors Influencing Farmers’ Participation in Forest Farmers Cooperatives Based on Empirical Research of Zhejiang Province

    Institute of Scientific and Technical Information of China (English)

    Wenyi; HUANG; Lanying; LI; Hongwei; TONG; Fei; WANG; Xueqin; CHEN

    2013-01-01

    Based on field research data of farmers in Zhejiang Province, the authors analyzed factors influencing farmers’ participation in forest farmers cooperatives (hereafter referred to as FFCs) by the binary logistic regression model. Results show that understanding of farmers about cooperatives has a great influence on their behavior of participation in FFCs. Besides, educational level of householders and existing member scale of cooperatives also have significant influence on farmers’ behavior of participation in cooperatives. Therefore, it is required to strengthen propaganda of cooperatives, deepen their understanding of cooperatives; cultivate new high quality farmers to provide talents for development of cooperatives; establish incentive mechanism to encourage farmers to participate in cooperatives.

  12. Outdoor field experience with autonomous RPC based stations

    Science.gov (United States)

    Lopes, L.; Assis, P.; Blanco, A.; Carolino, N.; Cerda, M. A.; Conceição, R.; Cunha, O.; Ferreira, M.; Fonte, P.; Luz, R.; Mendes, L.; Pereira, A.; Pimenta, M.; Sarmento, R.; Tomé, B.

    2016-09-01

    In the last two decades Resistive Plate Chambers were employed in the Cosmic Ray Experiments COVER-PLASTEX and ARGO/YBJ. In both experiments the detectors were housed indoors, likely owing to gas distribution requirements and the need to control environment variables that directly affect RPCs operational stability. But in experiments where Extended Air Shower (EAS) sampling is necessary, large area arrays composed by dispersed stations are deployed, rendering this kind of approach impossible. In this situation, it would be mandatory to have detectors that could be deployed in small standalone stations, with very rare opportunities for maintenance, and with good resilience to environmental conditions. Aiming to meet these requirements, we started some years ago the development of RPCs for Autonomous Stations. The results from indoor tests and measurements were very promising, both concerning performance and stability under very low gas flow rate, which is the main requirement for Autonomous Stations. In this work we update the indoor results and show the first ones concerning outdoor stable operation. In particular, a dynamic adjustment of the high voltage is applied to keep gas gain constant.

  13. Radiofrequency radiation injures trees around mobile phone base stations.

    Science.gov (United States)

    Waldmann-Selsam, Cornelia; Balmori-de la Puente, Alfonso; Breunig, Helmut; Balmori, Alfonso

    2016-12-01

    In the last two decades, the deployment of phone masts around the world has taken place and, for many years, there has been a discussion in the scientific community about the possible environmental impact from mobile phone base stations. Trees have several advantages over animals as experimental subjects and the aim of this study was to verify whether there is a connection between unusual (generally unilateral) tree damage and radiofrequency exposure. To achieve this, a detailed long-term (2006-2015) field monitoring study was performed in the cities of Bamberg and Hallstadt (Germany). During monitoring, observations and photographic recordings of unusual or unexplainable tree damage were taken, alongside the measurement of electromagnetic radiation. In 2015 measurements of RF-EMF (Radiofrequency Electromagnetic Fields) were carried out. A polygon spanning both cities was chosen as the study site, where 144 measurements of the radiofrequency of electromagnetic fields were taken at a height of 1.5m in streets and parks at different locations. By interpolation of the 144 measurement points, we were able to compile an electromagnetic map of the power flux density in Bamberg and Hallstadt. We selected 60 damaged trees, in addition to 30 randomly selected trees and 30 trees in low radiation areas (n=120) in this polygon. The measurements of all trees revealed significant differences between the damaged side facing a phone mast and the opposite side, as well as differences between the exposed side of damaged trees and all other groups of trees in both sides. Thus, we found that side differences in measured values of power flux density corresponded to side differences in damage. The 30 selected trees in low radiation areas (no visual contact to any phone mast and power flux density under 50μW/m(2)) showed no damage. Statistical analysis demonstrated that electromagnetic radiation from mobile phone masts is harmful for trees. These results are consistent with the fact

  14. Application of Risk-Based Inspection method for gas compressor station

    Science.gov (United States)

    Zhang, Meng; Liang, Wei; Qiu, Zeyang; Lin, Yang

    2017-05-01

    According to the complex process and lots of equipment, there are risks in gas compressor station. At present, research on integrity management of gas compressor station is insufficient. In this paper, the basic principle of Risk Based Inspection (RBI) and the RBI methodology are studied; the process of RBI in the gas compressor station is developed. The corrosion loop and logistics loop of the gas compressor station are determined through the study of corrosion mechanism and process of the gas compressor station. The probability of failure is calculated by using the modified coefficient, and the consequence of failure is calculated by the quantitative method. In particular, we addressed the application of a RBI methodology in a gas compressor station. The risk ranking is helpful to find the best preventive plan for inspection in the case study.

  15. Cooperation and Game between Producers and Managers Based on the Linear Contract

    Directory of Open Access Journals (Sweden)

    Xianglan Wan

    2014-01-01

    Full Text Available There is a cooperative game between the manager and the producer in the enterprise. In this paper, we firstly construct the cooperative game model based on the principal-agent theory. Under the conditions of Nash equilibrium and linear contract, the paper calculates the net income of the client, the total risk and welfare of the agents when the agents have the cooperation or not. The result shows that the correlation coefficient between their output has a direct relationship with the cooperation. Secondly, according to the power distribution theory another model is developed. We analyze the game process and critical state. Furthermore, we deduce the share proportion of the profit and the control size when they have the cooperation. Finally, we summarize all the research achievements, which are of universal significance for the practical cooperation game problems.

  16. Financial Support for Rural Cooperative Economy in China Based on Grey Correlation Analysis

    Institute of Scientific and Technical Information of China (English)

    Fuchang; XU; Chuandong; WANG

    2015-01-01

    This paper firstly analyzed current situations of financial support for rural cooperative economy in China and tested the correlation between rural finance and rural cooperative economy using the grey correlation analysis method. Results indicate that there is a close relationship between amount,structure and efficiency of rural finance and development of rural cooperative economy. The amount of rural finance has the largest promotion function to development of rural cooperative economy,the next is rural finance structure,and the least is efficiency of rural finance. Based on research conclusions,it came up with pertinent policy recommendations.

  17. GNSS-based network positioning technology for cooperative emergency management

    Science.gov (United States)

    Wu, Caicong; Chu, Tianxing; Tang, Anning; Su, Huaihong

    2009-06-01

    Personal digital assistant (PDA) with built-in GPS chip begins to be used for city management and emergency response management nowadays. The intelligent terminal can be used for event recording, multimedia (photo, audio, and video) capturing, wireless communication, GPS positioning and navigation. In the near future, PDA would take place of the vehicle GPS monitoring terminal to provide more functions and convenient. This article organizes the PDA of the same team for emergency response event into an integrated network through wireless communication so that each terminal can see each other on the map, including the vehicle GPS monitoring terminals. All of the terminals should send its GPS position and collected information to the emergency response center (ERC) through GPRS with a customized protocol. Then the center would create the socket connection to push the neighbors' location and common or special information to the others in the team according to the terminal's requirement and its authorities, and the leader or commander could send commands and messages to all of the underling members also. The GNSS based positioning and communication network organizes the dispersive emergency response personnel handheld with PDA and vehicles equipped with vehicle GPS monitoring terminal into an organic and cooperative network, each member in the network can see where its colleagues are, so as to seek for the help or support and exchange information in real time without calling which avoids exposure to the tracked objects. The Compass-1 satellite positioning and communication terminal is also used for personnel and vehicle positioning and message reporting. Altay is selected as the demonstration area. The prototype emergency management system is established for the local public security bureau and well validates the terminals and network function.

  18. Knowledge collaborative incentive based on inter-organizational cooperative innovation of project-based supply chain

    Directory of Open Access Journals (Sweden)

    Guangdong Wu

    2013-09-01

    Full Text Available Purpose: Within project-based supply chain inter-organizational cooperative innovation, the achievement of project value-adding reflects by factors such as project-based organizational effect level, the relationship between project cooperative innovation objectives etc. The purpose is to provide a reliable reference for the contractor reasonably allocate the effect level and resources between the knowledge input and innovation stage and realize the knowledge collaboration for project-based supply chain. Design/methodology/approach: Based on the assumption of equal cooperation between project-based organizations, from the view of maximizing project value-adding and the relationship of effect cost between knowledge input and innovation stage in consideration, the knowledge collaborative incentive model for project-based supply chain inter-organizational cooperative innovation was established, and solved through the first-order and second-order approach, then the digital simulation and example analysis were presented. Findings: The results show that, the project management enterprise resorted to adjust project knowledge collaboration incentive intensity and implemented knowledge input-innovation coordinative incentive strategy, not only could achieve project value-adding maximization, but also could realize net earnings Pareto improvement between project management enterprise and contractor. Research limitations/implications: To simplify the knowledge flow among project-based organizations, the knowledge flow in the model hypothesis is presented as knowledge input and knowledge innovation stage, thus it may affect the final analysis results. Originality/value: In construction project practice, knowledge is become more and more important to achieve project value-adding. The research can provide a theoretical guideline for the project-based organizations, such as the contractor, the owner, especially how to utilize their core knowledge.

  19. 外国空间站国际合作模式分析及对我国的启示%Analysis and Enl ightenment of lnternational Cooperation Patterns of Space Station

    Institute of Scientific and Technical Information of China (English)

    周黎妮; 朱启超; 张煌; 王姝

    2015-01-01

    Study the cooperation pattern of space station is very important for formulating interna‐tional cooperation plan on China Space Station.Firstly,patterns of international space cooperation is intro‐duced,including coordination,augmentation,interdependence and integration.The advantages and disadvantages of these four patterns are compared.Secondly,the evolution process and characteristics of cooperation on International Space Station (ISS)are analyzed.Finally,by reviewing cooperation patterns employed on China Manned Space Engineering Project,three patterns including augmenta‐tion,interdependence and integration are proposed for future cooperation on China Space Station.%分析研究国外空间站国际合作模式的运用方式和特点,对我国空间站国际合作方案设计具有重要借鉴意义。介绍国际太空合作模式理论,对比协商、配合、互助和融合4种模式的优缺点,梳理国际空间站合作模式的演变过程和特点;在总结我国载人航天工程前期国际合作模式运用的基础上,针对我国空间站工程可能开展的合作领域提出运用协商、配合和互助3种模式的初步思考。

  20. Research on Quantitative Models of Electric Vehicle Charging Stations Based on Principle of Energy Equivalence

    Directory of Open Access Journals (Sweden)

    Zhenpo Wang

    2013-01-01

    Full Text Available In order to adapt the matching and planning requirements of charging station in the electric vehicle (EV marketization application, with related layout theories of the gas stations, a location model of charging stations is established based on electricity consumption along the roads among cities. And a quantitative model of charging stations is presented based on the conversion of oil sales in a certain area. Both are combining the principle based on energy consuming equivalence substitution in process of replacing traditional vehicles with EVs. Defined data are adopted in the example analysis of two numerical case models and analyze the influence on charging station layout and quantity from the factors like the proportion of vehicle types and the EV energy consumption at the same time. The results show that the quantitative model of charging stations is reasonable and feasible. The number of EVs and the energy consumption of EVs bring more significant impact on the number of charging stations than that of vehicle type proportion, which provides a basis for decision making for charging stations construction layout in reality.

  1. Flywheel-Based Fast Charging Station – FFCS for Electric Vehicles and Public Transportation

    Science.gov (United States)

    Gabbar, Hossam A.; Othman, Ahmed M.

    2017-08-01

    This paper demonstrates novel Flywheel-based Fast Charging Station (FFCS) for high performance and profitable charging infrastructures for public electric buses. The design criteria will be provided for fast charging stations. The station would support the private and open charging framework. Flywheel Energy storage system is utilized to offer advanced energy storage for charging stations to achieve clean public transportation, including electric buses with reducing GHG, including CO2 emission reduction. The integrated modelling and management system in the station is performed by a decision-based control platform that coordinates the power streams between the quick chargers, the flywheel storage framework, photovoltaic cells and the network association. There is a tidy exchange up between the capacity rate of flywheel framework and the power rating of the network association.”

  2. Research on the Computer Supported Cooperative Shipbuilding System Based on PDM

    Institute of Scientific and Technical Information of China (English)

    YUE Weihong; WANG Chengfang; ZHANG Qingying

    2006-01-01

    Shipbuilding is becoming more complex and requires many different enterprises and plants to work cooperatively to strive for the maximum profit. Supported by the computer technology, information technology, and internet technology etc., CSCW (Computer Supported Cooperative Work) plays a very crucial role in the multi-team, multi-subject, multi-layer field. According to shipbuilding characters and market requirements, the computer supported cooperative shipbuilding technology is researched actually. Key technologies to realize it are analyzed, and construction of the computer supported cooperative manufacturing environment is deeply discussed. On the base of them, scheme of the computer supported cooperative shipbuilding system based on PDM (Product Data Management) is put forward, which is useful to improve and develop the shipbuilding industry.

  3. Experimental evaluation of a communication based cooperative driving algorithm

    NARCIS (Netherlands)

    Ploeg, J.; Gietelink, O.J.; Verburg, D.J.

    2006-01-01

    This paper presents a cooperative longitudinal control system for a cluster of vehicles using an environment sensor (radar) and vehicle-to-vehicle communication. The controller computes a desired acceleration that is realized by a lower-level control loop to obtain a smooth and safe traffic flow in

  4. Punishment based on public benefit fund significantly promotes cooperation.

    Directory of Open Access Journals (Sweden)

    Xiuling Wang

    Full Text Available In prisoner's dilemma game (shortly, PD game, punishment is most frequently used to promote cooperation. However, outcome varies when different punishment approaches are applied. Here the PD game is studied on a square lattice when different punishment patterns are adopted. As is known to all, tax system, a common tool to adjust the temperature of the economy, is widely used in human society. Inspired by this philosophy, players in this study would pay corresponding taxes in accordance with their payoff level. In this way, public benefit fund is established consequently and it would be utilized to punish defectors. There are two main methods for punishing: slight intensity of punishment (shortly, SLP and severe intensity of punishment (shortly, SEP. When the totaling of public benefit fund keeps relatively fixed, SLP extends further, which means more defectors would be punished; by contrast, SEP has a smaller coverage. It is of interest to verify whether these two measures can promote cooperation and which one is more efficient. Simulate results reveal that both of them can promote cooperation remarkably. Specifically speaking, SLP shows constant advantage from the point of view either of fractions of cooperation or average payoff.

  5. Influence of Mobile Users' Density Distribution on the CDMA Base Station Power

    Science.gov (United States)

    Lebl, Aleksandar; Mitić, Dragan; Popović, Miroslav; Markov, Žarko; Mileusnić, Mladen; Matić, Vladimir

    2016-12-01

    In this paper we analyze the influence of users' density distribution in one cell of CDMA mobile network (ie adjusted power control on the forward link) on base station emission power. This influence is analyzed for different circles radii around base station within which same emission power is generated for all mobile users, and for different values of propagation loss coefficient. It is proved that emission power in this cell must be increased comparing to the similar cell, which uses complete power control. The power increase is greater when greater number of users are situated near base station, and for greater values of propagation loss coefficient. The results are presented, illustrated by numerical examples and verified by simulation for three users' density distributions: uniform, decreasing and increasing density from the base station to the cell rim. The simulation process, which is based on random traffic process, is presented briefly.

  6. Cooperation and contagion in web-based, networked public goods experiments.

    Science.gov (United States)

    Suri, Siddharth; Watts, Duncan J

    2011-03-11

    A longstanding idea in the literature on human cooperation is that cooperation should be reinforced when conditional cooperators are more likely to interact. In the context of social networks, this idea implies that cooperation should fare better in highly clustered networks such as cliques than in networks with low clustering such as random networks. To test this hypothesis, we conducted a series of web-based experiments, in which 24 individuals played a local public goods game arranged on one of five network topologies that varied between disconnected cliques and a random regular graph. In contrast with previous theoretical work, we found that network topology had no significant effect on average contributions. This result implies either that individuals are not conditional cooperators, or else that cooperation does not benefit from positive reinforcement between connected neighbors. We then tested both of these possibilities in two subsequent series of experiments in which artificial seed players were introduced, making either full or zero contributions. First, we found that although players did generally behave like conditional cooperators, they were as likely to decrease their contributions in response to low contributing neighbors as they were to increase their contributions in response to high contributing neighbors. Second, we found that positive effects of cooperation were contagious only to direct neighbors in the network. In total we report on 113 human subjects experiments, highlighting the speed, flexibility, and cost-effectiveness of web-based experiments over those conducted in physical labs.

  7. Cooperation and contagion in web-based, networked public goods experiments.

    Directory of Open Access Journals (Sweden)

    Siddharth Suri

    Full Text Available A longstanding idea in the literature on human cooperation is that cooperation should be reinforced when conditional cooperators are more likely to interact. In the context of social networks, this idea implies that cooperation should fare better in highly clustered networks such as cliques than in networks with low clustering such as random networks. To test this hypothesis, we conducted a series of web-based experiments, in which 24 individuals played a local public goods game arranged on one of five network topologies that varied between disconnected cliques and a random regular graph. In contrast with previous theoretical work, we found that network topology had no significant effect on average contributions. This result implies either that individuals are not conditional cooperators, or else that cooperation does not benefit from positive reinforcement between connected neighbors. We then tested both of these possibilities in two subsequent series of experiments in which artificial seed players were introduced, making either full or zero contributions. First, we found that although players did generally behave like conditional cooperators, they were as likely to decrease their contributions in response to low contributing neighbors as they were to increase their contributions in response to high contributing neighbors. Second, we found that positive effects of cooperation were contagious only to direct neighbors in the network. In total we report on 113 human subjects experiments, highlighting the speed, flexibility, and cost-effectiveness of web-based experiments over those conducted in physical labs.

  8. Multiuser Radio Resource Allocation for Multiservice Transmission in OFDMA-Based Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Zhang Xing

    2009-01-01

    Full Text Available Abstract The problem of multiservice transmission in OFDMA-based cooperative relay networks is studied comprehensively. We propose a framework to adaptively allocate power, subcarriers, and data rate in OFDMA system to maximize spectral efficiency under the constraints of satisfying multiuser multiservices' QoS requirements. Specifically, first we concentrate on the single-user scenario which considers multiservice transmission in point-to-point cooperative relay network. Based on the analysis of single-user scenario, we extend the multiservice transmission to multiuser point-to-multipoint scenario. Next, based on the framework, we propose several suboptimal radio resource allocation algorithms for multiservice transmissions in OFDMA-based cooperative relay networks to further reduce the computational complexity. Simulation results show that the proposed algorithms yield much higher spectral efficiency and much lower outage probability, which are flexible and efficient for the OFDMA-based cooperative relay system.

  9. Occupational Exposure due to RF leakages within GSM Base Station Cabins in Eastern Nigeria

    National Research Council Canada - National Science Library

    Ayinmode, B. O; Jibiri, N. N; Farai, I. P

    2013-01-01

    ...) Radios and TX cables and during active radio communication was measured. A total of number 30 base stations Cabins were studied in the eastern part of Nigeria, using a Broad band TES-90 Electrosmog meter...

  10. Improved social force model based on exit selection for microscopic pedestrian simulation in subway station

    Institute of Scientific and Technical Information of China (English)

    郑勋; 李海鹰; 孟令云; 许心越; 陈旭

    2015-01-01

    An improved social force model based on exit selection is proposed to simulate pedestrians’ microscopic behaviors in subway station. The modification lies in considering three factors of spatial distance, occupant density and exit width. In addition, the problem of pedestrians selecting exit frequently is solved as follows: not changing to other exits in the affected area of one exit, using the probability of remaining preceding exit and invoking function of exit selection after several simulation steps. Pedestrians in subway station have some special characteristics, such as explicit destinations, different familiarities with subway station. Finally, Beijing Zoo Subway Station is taken as an example and the feasibility of the model results is verified through the comparison of the actual data and simulation data. The simulation results show that the improved model can depict the microscopic behaviors of pedestrians in subway station.

  11. Development of a web-based 3D virtual reality program for hydrogen station

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Younghee; Kim, Jinkyung; Kim, Junghwan; Moon, Il [Department of Chemical and Biomolecular Engineering, Yonsei University, 134 Shinchon-dong Seodaemun-ku, Seoul 120-749 (Korea); Kim, Eun Jung; Kim, Young Gyu [Institute of Gas Safety R and D, Korea Gas Safety Corporation, 322-1 Daeya-Dong Siheung-si, Kyonggi-do 429-712 (Korea)

    2010-03-15

    The hydrogen fueling station is an infrastructure of supplying fuel cell vehicles. It is necessary to guarantee the safety of hydrogen station equipment and operating procedure for decreasing intangible awareness of danger of hydrogen. Among many methods of securing the safety of the hydrogen stations, the virtual experience by dynamic simulation of operating the facilities and equipment is important. Thus, we have developed a virtual reality operator education system, and an interactive hydrogen safety training system. This paper focuses on the development of a virtual reality operator education of the hydrogen fueling station based on simulations of accident scenarios and hypothetical operating experience. The risks to equipment and personnel, associated with the manual operation of hydrogen fueling station demand rigorous personnel instruction. Trainees can practice how to use all necessary equipments and can experience twenty possible accident scenarios. This program also illustrates Emergency Response Plan and Standard Operating Procedure for both emergency and normal operations. (author)

  12. Assesment of Carbon Credits for Power Generation Systems at GSM Base Station Site

    OpenAIRE

    Ani, Vincent Anayochukwu; Ani, Emmanuel Onyeka

    2016-01-01

    Electricity production is often a source of CO2 emissions, for instance when fossil fuel is combusted in power plants. Therefore the root cause of pollution coming from telecommunication industry is the source of energy (diesel genset) the network operators used in running their Base station sites. Energy consumption of using diesel to power base station by telecom networks is a contributor to global greenhouse gas (GHG) emissions. This paper presents the comparative carbon credits of hybrid ...

  13. An Orthogonal Multi-Swarm Cooperative PSO Algorithm with a Particle Trajectory Knowledge Base

    Directory of Open Access Journals (Sweden)

    Jun Yang

    2017-01-01

    Full Text Available A novel orthogonal multi-swarm cooperative particle swarm optimization (PSO algorithm with a particle trajectory knowledge base is presented in this paper. Different from the traditional PSO algorithms and other variants of PSO, the proposed orthogonal multi-swarm cooperative PSO algorithm not only introduces an orthogonal initialization mechanism and a particle trajectory knowledge base for multi-dimensional optimization problems, but also conceives a new adaptive cooperation mechanism to accomplish the information interaction among swarms and particles. Experiments are conducted on a set of benchmark functions, and the results show its better performance compared with traditional PSO algorithm in aspects of convergence, computational efficiency and avoiding premature convergence.

  14. Recent advances in cooperative bimetallic asymmetric catalysis: dinuclear Schiff base complexes.

    Science.gov (United States)

    Matsunaga, Shigeki; Shibasaki, Masakatsu

    2014-02-04

    Cooperative catalysis has proven to be a powerful strategy for realizing high reactivity and selectivity in asymmetric transformations. A variety of cooperative asymmetric catalysts have been developed over the last two decades. In this feature article, recent advances from our research on cooperative asymmetric catalysis, focusing on dinuclear Schiff base catalysis, are described. Design of dinuclear Schiff base catalysts and their applications in several asymmetric C-C and C-N bond-forming reactions under simple proton transfer conditions with perfect atom-economy are discussed in detail.

  15. Aspiration-based learning promotes cooperation in spatial prisoner's dilemma games

    Science.gov (United States)

    Liu, Yongkui; Chen, Xiaojie; Wang, Long; Li, Bin; Zhang, Wenge; Wang, Huifeng

    2011-06-01

    We study the evolution of cooperation in spatial prisoner's dilemma by proposing an aspiration-based preference learning, under which individuals switch the learning agents only if the achieved payoffs are lower than their aspirations. Both synchronous and asynchronous updates are considered. We find that the aspiration level can substantially influence the evolution of cooperation, with the moderate aspiration level leading to a plateau of the high cooperation level. There exist phase transitions for proper combinations of parameters and we give an analysis for the phase transition points. We also investigate the stationary configuration patterns and the stationary distributions of cooperators and defectors on the square lattice for a comprehensive understanding. The behavior of the well-mixed system of our model has also been discussed. Our results may provide further insights into understanding the role played by individual aspiration in the emergence of cooperation.

  16. Target distribution in cooperative combat based on Bayesian optimization algorithm

    Institute of Scientific and Technical Information of China (English)

    Shi Zhifu; Zhang An; Wang Anli

    2006-01-01

    Target distribution in cooperative combat is a difficult and emphases. We build up the optimization model according to the rule of fire distribution. We have researched on the optimization model with BOA. The BOA can estimate the joint probability distribution of the variables with Bayesian network, and the new candidate solutions also can be generated by the joint distribution. The simulation example verified that the method could be used to solve the complex question, the operation was quickly and the solution was best.

  17. Judicial Cooperation Based On a European Evidence Warrant

    Directory of Open Access Journals (Sweden)

    Mihaela Laura Pamfil

    2009-06-01

    Full Text Available The assurance of a better judicial cooperation between European Union Member States is aconstant preoccupation of the Council of Europe, taking into consideration that the European Union has setitself the objective of maintaining and developing an area of freedom, security and justice. The achievementof this objective is only possible if among EU Member States there is a high level of confidence and a mutualrecognition of the decisions issued by the competent judicial authorities. The European arrest warrant was thefirst concrete measure in the field of criminal law implementing the principle of mutual recognition which theEuropean Council referred to as cornerstone of judicial cooperation. It was followed by other measuresdesigned to create the legal framework of the judicial cooperation; some of these measures concerns the fightagainst corruption, terrorism, cross-border criminality, racism and xenophobia while others are applicable inany case, such as the order of freezing the property and the evidence. On 18 December 2008, a newinstrument was created in order to improve the judicial cooperation between the Member States: the Europeanevidence warrant. Its purpose is to assure the obtaining of the objects, documents and data which may be usedas evidence in proceedings in criminal matters in issuing State, from another Member State. So, the aim ofthis Framework Decision is to complete the provision of the Decision on the execution of orders freezingproperty and evidence which is not talking about the transfer of the evidence after the freezing.Romania, like the other European Union Member States must transpose the provision of this Decision in thenational law by 19 January 2011. That is why we would like to analyse the procedures and the safeguardsprovided by this Decision and to show the way we see the European evidence warrant settled in ourlegislation.

  18. Broadband Cooperative Spectrum Sensing Based on Distributed Modulated Wideband Converter

    Directory of Open Access Journals (Sweden)

    Ziyong Xu

    2016-09-01

    Full Text Available The modulated wideband converter (MWC is a kind of sub-Nyquist sampling system which is developed from compressed sensing theory. It accomplishes highly accurate broadband sparse signal recovery by multichannel sub-Nyquist sampling sequences. However, when the number of sparse sub-bands becomes large, the amount of sampling channels increases proportionally. Besides, it is very hard to adjust the number of sampling channels when the sparsity changes, because its undersampling board is designed by a given sparsity. Such hardware cost and inconvenience are unacceptable in practical applications. This paper proposes a distributed modulated wideband converter (DMWC scheme innovatively, which regards one sensor node as one sampling channel and combines MWC technology with a broadband cooperative spectrum sensing network perfectly. Being different from the MWC scheme, DMWC takes phase shift and transmission loss into account in the input terminal, which are unavoidable in practical application. Our scheme is not only able to recover the support of broadband sparse signals quickly and accurately, but also reduces the hardware cost of the single node drastically. Theoretical analysis and numerical simulations show that phase shift has no influence on the recovery of frequency support, but transmission loss degrades the recovery performance to a different extent. Nevertheless, we can increase the amount of cooperative nodes and select satisfactory nodes by a different transmission distance to improve the recovery performance. Furthermore, we can adjust the amount of cooperative nodes flexibly when the sparsity changes. It indicates DMWC is extremely effective in the broadband cooperative spectrum sensing network.

  19. Are people living next to mobile phone base stations more strained? Relationship of health concerns, self-estimated distance to base station, and psychological parameters

    Directory of Open Access Journals (Sweden)

    Augner Christoph

    2009-01-01

    Full Text Available Background and Aims: Coeval with the expansion of mobile phone technology and the associated obvious presence of mobile phone base stations, some people living close to these masts reported symptoms they attributed to electromagnetic fields (EMF. Public and scientific discussions arose with regard to whether these symptoms were due to EMF or were nocebo effects. The aim of this study was to find out if people who believe that they live close to base stations show psychological or psychobiological differences that would indicate more strain or stress. Furthermore, we wanted to detect the relevant connections linking self-estimated distance between home and the next mobile phone base station (DBS, daily use of mobile phone (MPU, EMF-health concerns, electromagnetic hypersensitivity, and psychological strain parameters. Design, Materials and Methods: Fifty-seven participants completed standardized and non-standardized questionnaires that focused on the relevant parameters. In addition, saliva samples were used as an indication to determine the psychobiological strain by concentration of alpha-amylase, cortisol, immunoglobulin A (IgA, and substance P. Results: Self-declared base station neighbors (DBS ≤ 100 meters had significantly higher concentrations of alpha-amylase in their saliva, higher rates in symptom checklist subscales (SCL somatization, obsessive-compulsive, anxiety, phobic anxiety, and global strain index PST (Positive Symptom Total. There were no differences in EMF-related health concern scales. Conclusions: We conclude that self-declared base station neighbors are more strained than others. EMF-related health concerns cannot explain these findings. Further research should identify if actual EMF exposure or other factors are responsible for these results.

  20. Research on Multirobot Pursuit Task Allocation Algorithm Based on Emotional Cooperation Factor

    OpenAIRE

    Baofu Fang; Lu Chen; Hao Wang; Shuanglu Dai; Qiubo Zhong

    2014-01-01

    Multirobot task allocation is a hot issue in the field of robot research. A new emotional model is used with the self-interested robot, which gives a new way to measure self-interested robots’ individual cooperative willingness in the problem of multirobot task allocation. Emotional cooperation factor is introduced into self-interested robot; it is updated based on emotional attenuation and external stimuli. Then a multirobot pursuit task allocation algorithm is proposed, which is based on em...

  1. Polarimetric Analysis of the Interference from Base Stations to UHF-band Radar

    Directory of Open Access Journals (Sweden)

    Ren Bo

    2016-04-01

    Full Text Available Radar detection and tracking performance in the UHF-band can be influenced by the downlink signals of communication base stations. The polarimetric properties of interference from base stations are measured and analyzed as a basis for suppressing this type of interference by a polarization processing method. In this study, we establish signal models from the base station for dual-polarization UHF-band radar. We express the Probability Density Functions (PDF of the estimated polarization ratio and degree of polarization in a closed form and use them to describe the statistical properties of the interference environment. We developed polarimetric radar reception experiments for the signals from both Single-Base Stations (SBS and Multi-Base Stations (MBS. Experimental results proved that deterministic polarized descriptions are appropriate only for signals from SBS but not from MBS or from stations with a low DoP (Degree of Polarization. However, the proposed statistical method can be used to describe both SBS and MBS cases, which we demonstrated by comparing the theoretical models with real measurement data.

  2. Cooperation in Carrier Sense Based Wireless Ad Hoc Networks - Part I: Reactive Schemes

    CERN Document Server

    Munari, Andrea; Zorzi, Michele

    2012-01-01

    Cooperative techniques have been shown to significantly improve the performance of wireless systems. Despite being a mature technology in single communication link scenarios, their implementation in wider, and practical, networks poses several challenges which have not been fully identified and understood so far. In this two-part paper, the implementation of cooperative communications in non-centralized ad hoc networks with sensing-based channel access is extensively discussed. Both analysis and simulation are employed to provide a clear understanding of the mutual influence between the link layer contention mechanism and collaborative protocols. Part I of this work focuses on reactive cooperation, in which relaying is triggered by packet delivery failure events, while Part II addresses proactive approaches, preemptively initiated by the source based on channel state information. Results show that sensing-based channel access significantly hampers the effectiveness of cooperation by biasing the spatial distri...

  3. Bus transport network of Shenyang considering competitive and cooperative relationship

    Science.gov (United States)

    Hu, Baoyu; Feng, Shumin; Nie, Cen

    2017-01-01

    Competition and cooperation is a universal phenomenon in bus transport networks (BTNs) because of the shared stations between bus routes. A measuring method is proposed for competitive and cooperative relationship between bus routes. Based on this measurement, we develop a new representation model for BTNs, namely competitive-cooperative space R. This model is applied to investigate empirically bus transport network of Shenyang (BTN-S) from China. We present the histograms of competitive-cooperative coefficients, competitive coefficients and cooperative coefficients to illustrate that competitive and cooperative relationship plays an important role in transporting passengers. The competitive-cooperative situation shows that cooperative relationship holds an absolutely dominant position in BTN-S. To explore the networked characteristics, we present some empirical distributions, for the number of bus stations on a route, the number of shared stations between two routes, degree and weighted degree, competitive strength, and cooperative strength. We also examine the correlations between degree and competitive strength, and between degree and cooperative strength. Besides, we investigate the diversities of competitive strength and cooperative strength in BTN-S. This study can help us to understand the BTN from a deeper level.

  4. Adaptive Source Localization Based Station Keeping of Autonomous Vehicles

    KAUST Repository

    Guler, Samet

    2016-10-26

    We study the problem of driving a mobile sensory agent to a target whose location is specied only in terms of the distances to a set of sensor stations or beacons. The beacon positions are unknown, but the agent can continuously measure its distances to them as well as its own position. This problem has two particular applications: (1) capturing a target signal source whose distances to the beacons are measured by these beacons and broadcasted to a surveillance agent, (2) merging a single agent to an autonomous multi-agent system so that the new agent is positioned at desired distances from the existing agents. The problem is solved using an adaptive control framework integrating a parameter estimator producing beacon location estimates, and an adaptive motion control law fed by these estimates to steer the agent toward the target. For location estimation, a least-squares adaptive law is used. The motion control law aims to minimize a convex cost function with unique minimizer at the target location, and is further augmented for persistence of excitation. Stability and convergence analysis is provided, as well as simulation results demonstrating performance and transient behavior.

  5. Green Networking in Cellular HetNets: A Unified Radio Resource Management Framework with Base Station ON/OFF Switching

    KAUST Repository

    Ghazzai, Hakim

    2016-12-07

    In this paper, the problem of energy efficiency in cellular heterogeneous networks (HetNets) is investigated using radio resource and power management combined with the base station (BS) ON/OFF switching. The objective is to minimize the total power consumption of the network while satisfying the quality of service (QoS) requirements of each connected user. We consider the case of co-existing macrocell BS, small cell BSs, and private femtocell access points (FAPs). Three different network scenarios are investigated, depending on the status of the FAPs, i.e., HetNets without FAPs, HetNets with closed FAPs, and HetNets with semi-closed FAPs. A unified framework is proposed to simultaneously allocate spectrum resources to users in an energy efficient manner and switch off redundant small cell BSs. The high complexity dual decomposition technique is employed to achieve optimal solutions for the problem. A low complexity iterative algorithm is also proposed and its performances are compared to those of the optimal technique. The particularly interesting case of semi-closed FAPs, in which the FAPs accept to serve external users, achieves the highest energy efficiency due to increased degrees of freedom. In this paper, a cooperation scheme between FAPs and mobile operator is also investigated. The incentives for FAPs, e.g., renewable energy sharing and roaming prices, enabling cooperation are discussed to be considered as a useful guideline for inter-operator agreements.

  6. International Cooperation for Space-Based Global Maritime Awareness- The Next Step

    Science.gov (United States)

    Greidanus, H.; Thomas, G. G.; Campbell, G.; Bryan, K.

    2013-03-01

    This paper aims to put forward for discussion a number of possible ways to promote international cooperation for global maritime awareness, in particular using space-based assets. Maritime awareness concerns the knowledge of human activities going on at sea, so for a large part equates to ship traffic detection and monitoring for safety, security and protection of resources and the environment. The essential benefits and challenges for cooperation, and related sharing of information, are recounted. Several concrete options for global cooperation that should be viable also in view of the challenges are proposed. A public discussion with global stakeholders should follow, leading to convergence on a mechanism that should be subsequently implemented.

  7. Geometry Services Construction Based on Ontology towards Cooperative Design in Cloud Environment%Geometry Services Construction Based on Ontology towards Cooperative Design in Cloud Environment

    Institute of Scientific and Technical Information of China (English)

    CAI Hong-ming; BU Feng-lin; HE Yuan-jun

    2011-01-01

    APIs of CAD system could be encapsulated to construct web services so as to provide standard access interfaces for web-based cooperative design. However, lack of semantic supporting make integration of heterogeneous modelling system limited to operational level. On the purpose of carrying out cooperative design in a flexible cloud environment, an intelligent and effective support mechanism is needed for mass and complex interaction in cooperative work. Therefore, Ontology-based Geometry Modeling Services Environment (OGMSE) is provided to realize a knowledge-level geometry modeling so as to supported semantic 3D model management and intelligent operation support. First, CAD APIs are encapsulated into web service for web invocation. Then, ontology contained structural semantic and operational semantic is built for management of models and modeling process. Lastly, conception-driven modeling mechanism is built to invocate service according to interaction requirement, thus to realize conception-level cooperative design. Based on an open geometry engine, a prototype system has been developed. The result shows that the approach provides a reference direction for large-scale application on the network.

  8. Novel Radio on Fiber Access Eliminating External Electric Power Supply at Base Station

    Institute of Scientific and Technical Information of China (English)

    Tetsuya; Miki; Katsuyasu; Kawano; Nobuo; Nakajima; Naoto; Kishi; Masaru; Miyamoto; Tetsu; Aoki

    2003-01-01

    A novel Radio On Fiber(ROF) access is proposed and demonstrated which enables the pico-cell Base Station (BS) for high-speed wireless communications to eliminate external electric power supply facilities. We demonstrated 2.4-GHz band radio signal transmission through the BS without external electric power supply. The electrical power used for BS circuit is feeded by optical power over optical fiber from central station.

  9. Mobile phone base stations and well-being--A meta-analysis.

    Science.gov (United States)

    Klaps, Armin; Ponocny, Ivo; Winker, Robert; Kundi, Michael; Auersperg, Felicitas; Barth, Alfred

    2016-02-15

    It is unclear whether electromagnetic fields emitted by mobile phone base stations affect well-being in adults. The existing studies on this topic are highly inconsistent. In the current paper we attempt to clarify this question by carrying out a meta-analysis which is based on the results of 17 studies. Double-blind studies found no effects on human well-being. By contrast, field or unblinded studies clearly showed that there were indeed effects. This provides evidence that at least some effects are based on a nocebo effect. Whether there is an influence of electromagnetic fields emitted by mobile phone base stations thus depends on a person's knowledge about the presence of the presumed cause. Taken together, the results of the meta-analysis show that the effects of mobile phone base stations seem to be rather unlikely. However, nocebo effects occur.

  10. Study on DSM-based task planning of product cooperative development

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The results of analyzing the managerial characteristics and complexity of product cooperative development suggest that task planning is an important aspect for process management of product cooperative development and the method for planning tasks should be able to model the dependency between tasks and iterations during the development process. In this paper, a DSM-based method and its corresponding optimization algorithms are developed. At first the coupled task sets and uncoupled task sets are identified...

  11. Reputation-Based Conditional Interaction Supports Cooperation in Well-Mixed Prisoner’s Dilemmas

    Science.gov (United States)

    Chen, Xiaojie; Schick, Alana; Doebeli, Michael; Blachford, Alistair; Wang, Long

    2012-01-01

    In the well-mixed prisoner’s dilemma game, individuals are typically assumed to have no choice about whether to interact with other individuals in the population. In this paper, we instead consider reputation-based conditional interaction and its consequences for the evolution of cooperation. Each individual has a tolerance range, and only interacts with other individuals whose reputation lies within its tolerance range in a chosen sample of the population. Reputation contains information about the number of interaction partners an individual has just cooperated with. We find that the introduction of conditional interaction promotes cooperation in well-mixed populations, and there exist moderate tolerance ranges for which this effect is maximized. For a given tolerance range, there is a critical cost-to-benefit ratio below which cooperation can be promoted. Interestingly, we find that if cooperation evolves, different cooperators’ interaction clusters are typically maintained in the population, each around a different reputation level. We further investigate some properties of these cooperators’ clusters. Moreover, we examine the effects of the sample number on the evolution of cooperation. Our results highlight the importance of the detailed consideration of modes of interaction for the evolution of cooperation in well-mixed populations. PMID:22615761

  12. Design of a Base Station for MEMS CCR Localization in an Optical Sensor Network

    Directory of Open Access Journals (Sweden)

    Chan Gook Park

    2014-05-01

    Full Text Available This paper introduces a design and implementation of a base station, capable of positioning sensor nodes using an optical scheme. The base station consists of a pulse laser module, optical detectors and beam splitter, which are mounted on a rotation-stage, and a Time to Digital Converter (TDC. The optical pulse signal transmitted to the sensor node with a Corner Cube Retro-reflector (CCR is reflected to the base station, and the Time of Flight (ToF data can be obtained from the two detectors. With the angle and flight time data, the position of the sensor node can be calculated. The performance of the system is evaluated by using a commercial CCR. The sensor nodes are placed at different angles from the base station and scanned using the laser. We analyze the node position error caused by the rotation and propose error compensation methods, namely the outlier sample exception and decreasing the confidence factor steadily using the recursive least square (RLS methods. Based on the commercial CCR results, the MEMS CCR is also tested to demonstrate the compatibility between the base station and the proposed methods. The result shows that the localization performance of the system can be enhanced with the proposed compensation method using the MEMS CCR.

  13. Interorganizational Knowledge Division Decision Model Based on Cooperative Innovation of Supply Chain System

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2014-01-01

    Full Text Available Within interorganizational cooperative innovation of construction supply chain system, the achievement of project value-adding could be reflected by several factors, such as project-based organizational effect level, and the relationship between project cooperative innovation objectives. In this paper, based on the assumption of equal cooperation between project-based organizations, we selected the knowledge cooperation between the owner and contractor in construction supply chain system as research object. From the perspective of maximizing project value-adding and the relationship of effort cost between knowledge input and innovation stage in consideration, we established the knowledge collaborative incentive model for interorganizational cooperative innovation of construction supply chain system and proposed the first-order and second-order approaches. Then we conducted the digital simulation and example analysis, its results showed that if the owner has the capability to achieve project value-adding in knowledge cooperation, he would adopt a part commissioned way. Otherwise, a fully commissioned way would be better.

  14. An Analysis of Base Station Location Accuracy within Mobile-Cellular Networks

    Directory of Open Access Journals (Sweden)

    Liam Smit

    2015-05-01

    Full Text Available An important feature within a mobile-cellular net- work is that the location of a cellphone can be determined. As long as the cellphone is powered on, the location of the cellphone can always be traced to at least the cell from which it is receiving, or last received, signal from the cellular network. Such network-based methods of estimating the location of a cellphone is useful in cases where the cellphone user is unable or unwilling to reveal his or her location, and have practical value in digital forensic investigations. This study investigates the accuracy of using mobile-cellular network base station information for estimating the location of cellphones. Through quantitative analysis of mobile-cellular network base station data, large variations between the best and worst accuracy of recorded location information is exposed. Thus, depending on the requirements, base station locations may or may not be accurate enough for a particular application.

  15. A framework for recovery-oriented, COTS-based ground station networks

    Science.gov (United States)

    Cutler, James William

    The complexity of space communication has limited our access to space systems and kept mission operations costs high. Ultimately, this results in reduced mission capabilities and yields. In particular, ground stations, the access point between space and terrestrial networks, suffer from monolithic designs, narrow interfaces, and unreliability that raise significant financial barriers for low-cost, experimental satellite missions. This research reduces these barriers by developing technology for recovery-oriented, flexible access networks built from commercial-off-the-shelf (COTS) components. Based on our extensive small satellite experiences, we decomposed ground station services and captured them in an extensible framework that simplified reuse of ground station services and improved portability across heterogeneous installations. This capability, combined with selective customization through virtual machine technology, allowed us to deliver "just in time" ground stations for QuakeSat-1 at a fraction of the price of current commodity solutions. This decomposition is also informed by principles of robust system design. Thus, our ground station reference implementation called Mercury was a candidate for recursive recovery (RR), a high availability technique whose effectiveness in reducing recovery time has been demonstrated on research prototypes of Internet server systems. Augmenting Mercury to implement RR reduced recovery time of typical ground station software failures by a factor of four, dropping recovery time to within the "window of recovery" and effectively eliminating the adverse effects of these failures. Since the time of failures cannot be predicted, RR allowed us to mitigate the effects of the failures and greatly reduce their potential impact on ground station operations. Our ground station architecture harnessed the benefits of COTS components, including rapid prototyping and deployment, while overcoming the challenges of COTS reliability and mission

  16. Cross-border innovation cooperation: Partner selection, national borders and knowledge bases

    DEFF Research Database (Denmark)

    Hjaltadóttir, Rannveig Edda; Makkonen, Teemu; Sørensen, Nils Karl

    2017-01-01

    Finding a suitable partner is paramount for the success of innovation cooperation. Thus, this paper sets out to analyse the determinants of cross-border innovation cooperation in Denmark by focusing on partner selection. The aim of the article is to investigate determinants of partner selection...... by taking the location of the partners into account. In particular, the discussion is tied to the notion of varying knowledge bases firms utilize in their innovation creation processes. Firm level data from the 2010 Community Innovation Survey in Denmark was utilized to analyse cross-border innovation...... cooperation patterns of Danish firms focusing on their choices of foreign innovation partners. The results indicate that firm size and research and development (R&D) intensity have a positive effect on firm’s propensity to cooperate on innovation and that having R&D activities abroad as well as high level...

  17. Practice and Evaluation of a Cooperative Learning Support on Educational Function as Teamwork in Project-based Learning with Regional Cooperation

    Science.gov (United States)

    Aoki, Hideyuki; Kamata, Motohiro; Yamagami, Norihisa

    The purpose of my study was to develop of cooperative learning support on Educational Function as Teamwork in Project-based Learning with Regional Cooperation. Analysis of validation of the original method were made using correlation analysis of student satisfaction of relationships among teammate and educational function as teamwork, result of self-diagnose. As a result, we achieved analysis results with a collective creativity were involved in student‧s planning skill. It was shown that educational functions as teamwork plays an important part in the growth of students. Our study revealed that there was method using cooperative learning technique helps to promote improvement of educational function as teamwork.

  18. A HYBRID APPROACH FOR NODE CO-OPERATION BASED CLUSTERING IN MOBILE AD HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    C. Sathiyakumar

    2013-01-01

    Full Text Available A Mobile Ad-Hoc Network (MANET is termed as a set of wireless nodes which could be built with infrastructure less environment where network services are afforded by the nodes themselves. In such a situation, if a node refuses to co-operate with other nodes, then it will lead to a considerable diminution in throughput and the network operation decreases to low optimum value. Mobile Ad hoc Networks (MANETs rely on the collaboration of nodes for packet routing ahead. Nevertheless, much of the existing work in MANETs imagines that mobile nodes (probably possessed by selfish users will pursue prearranged protocols without variation. Therefore, implementing the co-operation between the nodes turn out to be an significant issue. The previous work described a secured key model for ad hoc network with efficient node clustering based on reputation and ranking model. But the downside is that the co-operation with the nodes is less results in a communication error. To enhance the security in MANET, in this work, we present a hybrid approach, build a node co-operation among the nodes in MANET by evaluating the weightage of cooperativeness of each node in MANET. With the estimation of normal co-operative nodes, nodes are restructured on its own (self. Then clustering is made with the reorganized nodes to form a secured communication among the nodes in the MANET environment. The Simulation of the proposed Hybrid Approach for Node Cooperation based Clustering (HANCC work is done for varying topology, node size, attack type and intensity with different pause time settings and the performance evaluations are carried over in terms of node cooperativeness, clustering efficiency, communication overhead and compared with an existing secured key model. Compared to an existing secured key model, the proposed HANCC performance is 80-90% high.

  19. Consensus-Based Cooperative Control Based on Pollution Sensing and Traffic Information for Urban Traffic Networks.

    Science.gov (United States)

    Artuñedo, Antonio; Del Toro, Raúl M; Haber, Rodolfo E

    2017-04-26

    Nowadays many studies are being conducted to develop solutions for improving the performance of urban traffic networks. One of the main challenges is the necessary cooperation among different entities such as vehicles or infrastructure systems and how to exploit the information available through networks of sensors deployed as infrastructures for smart cities. In this work an algorithm for cooperative control of urban subsystems is proposed to provide a solution for mobility problems in cities. The interconnected traffic lights controller (TLC) network adapts traffic lights cycles, based on traffic and air pollution sensory information, in order to improve the performance of urban traffic networks. The presence of air pollution in cities is not only caused by road traffic but there are other pollution sources that contribute to increase or decrease the pollution level. Due to the distributed and heterogeneous nature of the different components involved, a system of systems engineering approach is applied to design a consensus-based control algorithm. The designed control strategy contains a consensus-based component that uses the information shared in the network for reaching a consensus in the state of TLC network components. Discrete event systems specification is applied for modelling and simulation. The proposed solution is assessed by simulation studies with very promising results to deal with simultaneous responses to both pollution levels and traffic flows in urban traffic networks.

  20. Non-Coop Station History (Unindexed)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Station history documentation for stations outside the US Cooperative Observer network. Documents should be compared with those in the Non-Coop Station History...

  1. Scalable Base-Station Model-Based Multicast in Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    Shao-Liang Peng; Shan-Shan Li; Lei Chen; Yu-Xing Peng; Nong Xiao

    2008-01-01

    Multicast is essential for wireless sensor network (WSN) applications. Existing multicast protocols in WSNs are often designed in a P2P pattern, assuming small number of destination nodes and frequent changes in network topologies.In order to truly adopt multicast in WSNs, we propose a base-station model-based multicast, SenCast, to meet the general requirements of applications. SenCast is scalable and energy-efficient for large group communications in WSNs. Theoretical analysis shows that SenCast is able to approximate the Minimum Nonleaf Nodes (MNN) problem to a ratio of In |R| (R is the set of all destinations), the best known lowest bound. We evaluate our design through comprehensive simulations and prototype implementations on Mica2 motes. Experimental results demonstrate that SenCast outperforms previous multicast protocols including the most recent work uCast.

  2. Inquiry and groups: student interactions in cooperative inquiry-based science

    Science.gov (United States)

    Woods-McConney, Amanda; Wosnitza, Marold; Sturrock, Keryn L.

    2016-03-01

    Science education research has recommended cooperative inquiry based science in the primary science context for more than two decades but after more than 20 years, student achievement in science has not substantially improved. This study, through direct observation and analysis, investigated content-related student interactions in an authentic inquiry based primary science class setting. Thirty-one upper primary students were videotaped working in cooperative inquiry based science activities. Cooperative talk and negotiation of the science content was analysed to identify any high-level group interactions. The data show that while all groups have incidences of high-level content-related group interactions, the frequency and duration of these interactions were limited. No specific pattern of preceding events was identified and no episodes of high-level content-related group interactions were immediately preceded by the teacher's interactions with the groups. This in situ study demonstrated that even without any kind of scaffolding, specific skills in knowing how to implement cooperative inquiry based science, high-level content-related group interactions did occur very briefly. Support for teachers to develop their knowledge and skills in facilitating cooperative inquiry based science learning is warranted to ensure that high-level content-related group interactions and the associated conceptual learning are not left to chance in science classrooms.

  3. Efficient ways for setting up the operation of nuclear power stations in power systems in the base load mode

    Science.gov (United States)

    Aminov, R. Z.; Shkret, A. F.; Burdenkova, E. Yu.; Garievskii, M. V.

    2011-05-01

    The results obtained from studies of efficient ways and methods for organizing the operation of developing nuclear power stations in the base load mode are presented. We also show comparative efficiency of different scenarios for unloading condensing thermal power stations, cogeneration stations, combined-cycle power plants, nuclear power stations, and using off-peak electric energy for electricity-intensive loads: pumped-hydroelectric storage, electric-powered heat supply, and electrolysis of water for producing hydrogen and oxygen.

  4. Optimized Envelope Tracking Power Supply for Tetra2 Base Station RF Power Amplifier

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    2008-01-01

    An ultra-fast tracking power supply (UFTPS) for envelope tracking in a 50kHz 64-QAM Tetra2 base station power amplification system is demonstrated. A simple method for optimizing the step response of the PID+PD sliding-mode control system is presented and demonstrated, along with a PLL-based scheme...

  5. TEDS Base Station Power Amplifier using Low-Noise Envelope Tracking Power Supply

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael A. E.

    2009-01-01

    This paper demonstrates a highly linear and efficient TETRA enhanced data service (TEDS) base-station RF power amplifier (RFPA). Based on the well-known combination of an envelope tracking (ET) power supply and a linear class-A/B RFPA, adequate adjacent channel power ratio (ACPR) and wideband noise...

  6. Base station selection for energy efficient network operation with the majorization-minimization algorithm

    CERN Document Server

    Pollakis, Emmanuel; Stańczak, Slawomir

    2012-01-01

    In this paper, we study the problem of reducing the energy consumption in a mobile communication network; we select the smallest set of active base stations that can preserve the quality of service (the minimum data rate) required by the users. In more detail, we start by posing this problem as an integer programming problem, the solution of which shows the optimal assignment (in the sense of minimizing the total energy consumption) between base stations and users. In particular, this solution shows which base stations can then be switched off or put in idle mode to save energy. However, solving this problem optimally is intractable in general, so in this study we develop a suboptimal approach that builds upon recent techniques that have been successfully applied to, among other problems, sparse signal reconstruction, portfolio optimization, statistical estimation, and error correction. More precisely, we relax the original integer programming problem as a minimization problem where the objective function is ...

  7. DBSR: Dynamic base station Repositioning using Genetic algorithm in wireless sensor network

    CERN Document Server

    Mollanejad, Amir; Zeynali, Mohammad

    2010-01-01

    Wireless sensor networks (WSNs) are commonly used in various ubiquitous and pervasive applications. Due to limited power resources, the optimal dynamic base station (BS) replacement could be Prolong the sensor network lifetime. In this paper we'll present a dynamic optimum method for base station replacement so that can save energy in sensors and increases network lifetime. Because positioning problem is a NPhard problem [1], therefore we'll use genetic algorithm to solve positioning problem. We've considered energy and distance parameters for finding BS optimized position. In our represented algorithm base station position is fixed just during each round and its positioning is done at the start of next round then it'll be placed in optimized position. Evaluating our proposed algorithm, we'll execute DBSR algorithm on LEACH & HEED Protocols.

  8. Field trial of an HTS filter system on a CDMA base station

    Institute of Scientific and Technical Information of China (English)

    YIN ZheSheng; LIANG Yong; WANG Fan; H. PIEL; B. AMINOV; F. AMINOVA; M. GETTA; S. KOLESOV; A. KNACK; N. PUPETER; D. WEHLER; WEI Bin; CAO BiSong; WANG Xin; GUO XuBo; ZHANG XiaoPing; GAO LongMa; PIAO YunLong; ZHU MaFeng

    2007-01-01

    This paper presents the field trial results of a high temperature superconductor filter system (HTSFS) in a code division multiple access (CDMA) mobile communication base station (BTS) in Tangshan, China. The center frequency of the HTSFS is 830 MHz with 1.4% fractional bandwidth. The noise figure (NF) of the HTSFS, including connectors and cables, is 0.8 dB. The field trial results show that after the HTSFS was installed in the receiver front-end of a CDMA base station, the transmitting power of handset was decreased by 3.1 dB on average. Up to now, the HTSFS has been running steadily in the base station for more than 22 months, demonstrating the reliability and stability of the system.

  9. A Technical Approach to the Evaluation of Radiofrequency Radiation Emissions from Mobile Telephony Base Stations.

    Science.gov (United States)

    Buckus, Raimondas; Strukčinskienė, Birute; Raistenskis, Juozas; Stukas, Rimantas; Šidlauskienė, Aurelija; Čerkauskienė, Rimantė; Isopescu, Dorina Nicolina; Stabryla, Jan; Cretescu, Igor

    2017-03-01

    During the last two decades, the number of macrocell mobile telephony base station antennas emitting radiofrequency (RF) electromagnetic radiation (EMR) in residential areas has increased significantly, and therefore much more attention is being paid to RF EMR and its effects on human health. Scientific field measurements of public exposure to RF EMR (specifically to radio frequency radiation) from macrocell mobile telephony base station antennas and RF electromagnetic field (EMF) intensity parameters in the environment are discussed in this article. The research methodology is applied according to the requirements of safety norms and Lithuanian Standards in English (LST EN). The article presents and analyses RF EMFs generated by mobile telephony base station antennas in areas accessible to the general public. Measurements of the RF electric field strength and RF EMF power density were conducted in the near- and far-fields of the mobile telephony base station antenna. Broadband and frequency-selective measurements were performed outside (on the roof and on the ground) and in a residential area. The tests performed on the roof in front of the mobile telephony base station antennas in the near-field revealed the presence of a dynamic energy interaction within the antenna electric field, which changes rapidly with distance. The RF EMF power density values on the ground at distances of 50, 100, 200, 300, 400, and 500 m from the base station are very low and are scattered within intervals of 0.002 to 0.05 μW/cm². The results were compared with international exposure guidelines (ICNIRP).

  10. Analysis of lifetime of wireless sensor network with base station moving on different paths

    Science.gov (United States)

    Singh, Ashutosh Kumar; Purohit, N.; Varma, S.

    2014-05-01

    Energy saving is the top most requirement of the wireless sensor network (WSN) for making it a cost effective technology. In this direction, minimisation of the distance between the communicating nodes should be an obvious choice, as it consumes the biggest chunk of the node energy. But the stationary nature of nodes (including the base station) in the standard WSN does not allow it; thus, the provision of a moving base station has been recently introduced. A few schemes with moving base station have already been developed but they suffer from several drawbacks, for example, the path over which the base station can move has not been considered which is highly unfeasible. An efficient and implementable moving strategy is needed to be developed, which is the primary goal of the present work. The fuzzy logic inference mechanism has been developed and the performance of the same is illustrated in terms of WSN lifetime. Lifetime of a WSN depends on many factors, for example, residual energy of nodes, distance between communicating nodes and base station, etc. Ability of fuzzy logic theory to address more than one factor simultaneously gives it an upper edge over other alternatives. The present work explores the possibilities of building either a circular shaped or a cross-shaped path in the deployment area. A relative study of the movement of base station on these paths has been presented. Simulation results show that the cross path always give better performance than circular path and the lifetime improves with increase in the length of the predefined path.

  11. Load forecast method of electric vehicle charging station using SVR based on GA-PSO

    Science.gov (United States)

    Lu, Kuan; Sun, Wenxue; Ma, Changhui; Yang, Shenquan; Zhu, Zijian; Zhao, Pengfei; Zhao, Xin; Xu, Nan

    2017-06-01

    This paper presents a Support Vector Regression (SVR) method for electric vehicle (EV) charging station load forecast based on genetic algorithm (GA) and particle swarm optimization (PSO). Fuzzy C-Means (FCM) clustering is used to establish similar day samples. GA is used for global parameter searching and PSO is used for a more accurately local searching. Load forecast is then regressed using SVR. The practical load data of an EV charging station were taken to illustrate the proposed method. The result indicates an obvious improvement in the forecasting accuracy compared with SVRs based on PSO and GA exclusively.

  12. HTS filter and front-end subsystem for GSM1800 wireless base station

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The first HTS front-end subsystem for wireless base station in China was developed. This demonstration system, which aims at the application in GSM1800 mobile communication base station, consists of a single RF path, i.e. one filter and one LNA, integrated with the pulse tube cooler. The subsystem works at a pass band of 1710-1785 MHz with a gain of 18 dB and at a temperature of 70 K. The accomplishment of such a demonstration subsystem can boost the development of HTS commercial subsystem.

  13. PV-solar / wind hybrid energy system for GSM/CDMA type mobile telephony base station

    OpenAIRE

    Pragya Nema, R.K. Nema, Saroj Rangnekar

    2010-01-01

    This paper gives the design idea of optimized PV-Solar and Wind Hybrid Energy System for GSM/CDMA type mobile base station over conventional diesel generator for a particular site in central India (Bhopal) . For this hybrid system ,the meteorological data of Solar Insolation, hourly wind speed, are taken for Bhopal-Central India (Longitude 77o.23'and Latitude 23o.21' ) and the pattern of load consumption of mobile base station are studied and suitably modeled for optimization of the hybrid en...

  14. Novel Base Station MIMO Antennas with Enhanced Spectral Efficiencies Using Angular Reuse

    Directory of Open Access Journals (Sweden)

    Miguel Mora-Andreu

    2015-01-01

    Full Text Available The true polarization diversity (TPD technique is combined with the spatial diversity technique in novel MIMO antenna array geometries with a large number of elements. The use of a large number of elements requires some angular reuse within the array for polarization diversity. With designs compatible with existing base station antenna array configurations, the novel geometries with combining diversity schemes are shown to be able to achieve near the maximum spectral efficiencies. True polarization diversity (TPD schemes are found to be an excellent complement to more conventional spatial diversity schemes for obtaining optimum MIMO array performance in base station antennas.

  15. LQR-Based Optimal Distributed Cooperative Design for Linear Discrete-Time Multiagent Systems.

    Science.gov (United States)

    Zhang, Huaguang; Feng, Tao; Liang, Hongjing; Luo, Yanhong

    2017-03-01

    In this paper, a novel linear quadratic regulator (LQR)-based optimal distributed cooperative design method is developed for synchronization control of general linear discrete-time multiagent systems on a fixed, directed graph. Sufficient conditions are derived for synchronization, which restrict the graph eigenvalues into a bounded circular region in the complex plane. The synchronizing speed issue is also considered, and it turns out that the synchronizing region reduces as the synchronizing speed becomes faster. To obtain more desirable synchronizing capacity, the weighting matrices are selected by sufficiently utilizing the guaranteed gain margin of the optimal regulators. Based on the developed LQR-based cooperative design framework, an approximate dynamic programming technique is successfully introduced to overcome the (partially or completely) model-free cooperative design for linear multiagent systems. Finally, two numerical examples are given to illustrate the effectiveness of the proposed design methods.

  16. Time Averaged Transmitter Power and Exposure to Electromagnetic Fields from Mobile Phone Base Stations

    Directory of Open Access Journals (Sweden)

    Alfred Bürgi

    2014-08-01

    Full Text Available Models for exposure assessment of high frequency electromagnetic fields from mobile phone base stations need the technical data of the base stations as input. One of these parameters, the Equivalent Radiated Power (ERP, is a time-varying quantity, depending on communication traffic. In order to determine temporal averages of the exposure, corresponding averages of the ERP have to be available. These can be determined as duty factors, the ratios of the time-averaged power to the maximum output power according to the transmitter setting. We determine duty factors for UMTS from the data of 37 base stations in the Swisscom network. The UMTS base stations sample contains sites from different regions of Switzerland and also different site types (rural/suburban/urban/hotspot. Averaged over all regions and site types, a UMTS duty factor  for the 24 h-average is obtained, i.e., the average output power corresponds to about a third of the maximum power. We also give duty factors for GSM based on simple approximations and a lower limit for LTE estimated from the base load on the signalling channels.

  17. Time averaged transmitter power and exposure to electromagnetic fields from mobile phone base stations.

    Science.gov (United States)

    Bürgi, Alfred; Scanferla, Damiano; Lehmann, Hugo

    2014-08-07

    Models for exposure assessment of high frequency electromagnetic fields from mobile phone base stations need the technical data of the base stations as input. One of these parameters, the Equivalent Radiated Power (ERP), is a time-varying quantity, depending on communication traffic. In order to determine temporal averages of the exposure, corresponding averages of the ERP have to be available. These can be determined as duty factors, the ratios of the time-averaged power to the maximum output power according to the transmitter setting. We determine duty factors for UMTS from the data of 37 base stations in the Swisscom network. The UMTS base stations sample contains sites from different regions of Switzerland and also different site types (rural/suburban/urban/hotspot). Averaged over all regions and site types, a UMTS duty factor for the 24 h-average is obtained, i.e., the average output power corresponds to about a third of the maximum power. We also give duty factors for GSM based on simple approximations and a lower limit for LTE estimated from the base load on the signalling channels.

  18. When Creative Problem Solving Strategy Meets Web-Based Cooperative Learning Environment in Accounting Education

    Science.gov (United States)

    Cheng, Kai Wen

    2011-01-01

    Background: Facing highly competitive and changing environment, cultivating citizens with problem-solving attitudes is one critical vision of education. In brief, the importance of education is to cultivate students with practical abilities. Realizing the advantages of web-based cooperative learning (web-based CL) and creative problem solving…

  19. Differential roles of fairness- and compassion-based motivations for cooperation, defection, and punishment.

    Science.gov (United States)

    Singer, Tania; Steinbeis, Nikolaus

    2009-06-01

    The present paper briefly describes and contrasts two different motivations crucially involved in decision making and cooperation, namely fairness-based and compassion-based motivation. Whereas both can lead to cooperation in comparable social situations, we suggest that they are driven by fundamentally different mechanisms and, overall, predict different behavioral outcomes. First, we provide a brief definition of each and discuss the relevant behavioral and neuroscientific literature with regards to cooperation in the context of economic games. We suggest that, whereas both fairness- and compassion-based motivation can support cooperation, fairness-based motivation leads to punishment in cases of norm violation, while compassion-based motivation can, in cases of defection, counteract a desire for revenge and buffer the decline into iterative noncooperation. However, those with compassion-based motivation alone may get exploited. Finally, we argue that the affective states underlying fairness-based and compassion-based motivation are fundamentally different, the former driven by anger or fear of being punished and the latter by a wish for the other person's well-being.

  20. The data platform of national special environment and disaster field observation stations based on grid environment

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Data Platform of Resource and Environment-whose data mainly come from field observation stations,spatial observations,and internet service institutions-is the base of data analysis and model simulation in geoscience research in China.Among this integrated data platform,the tasks of the data platform of field observation stations are principally data collection,management,assimilation,and share service.Taking into consideration the distributing characteristics of the data sources and the service objects,the authors formulated the framework of the field observation stations’ data platform based on the grid technology and designed its operating processes.The authors have further defined and analyzed the key functions and implementing techniques for each module.In a Linux operating system,validation tests for the data platform’s function on data replication,data synchronization,and unified data service have been conducted under an environment that of the simulating field stations.

  1. Statistical analysis of electromagnetic radiation measurements in the vicinity of indoor microcell GSM/UMTS base stations in Serbia.

    Science.gov (United States)

    Koprivica, Mladen; Petrić, Majda; Nešković, Nataša; Nešković, Aleksandar

    2016-01-01

    To determine the level of radiofrequency radiation generated by base stations of Global System for Mobile Communications and Universal Mobile Telecommunication System, extensive electromagnetic field strength measurements were carried out in the vicinity of 664 base station locations. These were classified into three categories: indoor, masts, and locations with installations on buildings. Although microcell base stations with antennas installed indoors typically emit less power than outdoor macrocell base stations, the fact that people can be found close to antennas requires exposure originating from these base stations to be carefully considered. Measurement results showed that maximum recorded value of electric field strength exceeded International Commission on Non-Ionizing Radiation Protection reference levels at 7% of indoor base station locations. At the same time, this percentage was much lower in the case of masts and installations on buildings (0% and 2.5%, respectively).

  2. Implementation of a Smart Antenna Base Station for Mobile WiMAX Based on OFDMA

    Directory of Open Access Journals (Sweden)

    Seungheon Hyeon

    2009-01-01

    Full Text Available We present an implementation of a mobile-WiMAX (m-WiMAX base station (BS that supports smart antenna (SA functionality. To implement the m-WiMAX SA BS, we must address a number of key issues in baseband signal processing related to symbol-timing acquisition, the beamforming scheme, and accurate calibration. We propose appropriate solutions and implement an m-WiMAX SA BS accordingly. Experimental tests were performed to verify the validity of the solutions. Results showed a 3.5-time (5.5 dB link-budget enhancement on the uplink compared to a single antenna system. In addition, the experimental results were consistent with the results of the computer simulation.

  3. Reconfigurable and Tunable Filtenna for Cognitive LTE Femtocell Base Stations

    Directory of Open Access Journals (Sweden)

    Hamza Nachouane

    2016-01-01

    Full Text Available A single-port uniplanar antenna with a built-in tunable filter is presented for operation in multiple LTE bands for cognitive femtocell applications. The antenna is based on a monopole microstrip patch fed by coplanar waveguide. The frequency reconfigurability is achieved by using two PIN diodes to couple or decouple a ring slot resonator filter from the antenna feed line. By switching the PIN diodes, the proposed design can operate in either wideband or narrowband modes. When the antenna operates in the narrowband state, two varactor diodes are used to continuously tune the narrowband frequency from 2.55 to 3.2 GHz, while the wideband state is obtained over the 1.35–6.2 GHz band. The diodes and their biasing networks have nearly no severe effect on the antenna characteristics. Prototypes of the proposed structure using ideal and real switches, with and without varactors, are fabricated and tested. Measured and simulated results are in good agreement, thus verifying the good performance of the proposed design. The obtained results show that the proposed antenna is very suitable for cognitive radio applications, in which the wideband mode is used for spectrum sensing and the narrowband mode for transmission at different frequency bands.

  4. Adaptive Opportunistic Cooperative Control Mechanism Based on Combination Forecasting and Multilevel Sensing Technology of Sensors for Mobile Internet of Things

    Directory of Open Access Journals (Sweden)

    Yong Jin

    2014-01-01

    Full Text Available In mobile Internet of Things, there are many challenges, including sensing technology of sensors, how and when to join cooperative transmission, and how to select the cooperative sensors. To address these problems, we studied the combination forecasting based on the multilevel sensing technology of sensors, building upon which we proposed the adaptive opportunistic cooperative control mechanism based on the threshold values such as activity probability, distance, transmitting power, and number of relay sensors, in consideration of signal to noise ratio and outage probability. More importantly, the relay sensors would do self-test real time in order to judge whether to join the cooperative transmission, for maintaining the optimal cooperative transmission state with high performance. The mathematical analyses results show that the proposed adaptive opportunistic cooperative control approach could perform better in terms of throughput ratio, packet error rate and delay, and energy efficiency, compared with the direct transmission and opportunistic cooperative approaches.

  5. Research on applying the interests distribution method of enterprise-university-research institute cooperation based on hash model

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-dong

    2007-01-01

    In order to get an acceptable interests-distribution scheme for each partner of enterprise-university-research institute cooperation in advance, based on Nash model, the paper designs the interest distribution method of enterprise-university-research institute cooperation and provides the basis for determining the weight of each partner in accordance with the interest distribution principles and subjected relations between major factors in enterprise-university-research institute cooperation. Also, in combination with one example, an applicable method is provided to distribute interest in enterprise-university-research institute cooperation. The study gives some references for interests-distribution of enterprise-university-research institute cooperation.

  6. Streamflow characteristics based on data through water year 2009 for selected streamflow-gaging stations in or near Montana: Chapter E in Montana StreamStats

    Science.gov (United States)

    McCarthy, Peter M.

    2016-04-05

    Chapter E of this Scientific Investigations Report documents results from a study by the U.S. Geological Survey, in cooperation with the Montana Department of Environmental Quality and the Montana Department of Natural Resources and Conservation, to provide an update of statewide streamflow characteristics based on data through water year 2009 for streamflow-gaging stations in or near Montana. Streamflow characteristics are presented for 408 streamflow-gaging stations in Montana and adjacent areas having 10 or more years of record. Data include the magnitude and probability of annual low and high streamflow, the magnitude and probability of low streamflow for three seasons (March–June, July–October, and November–February), streamflow duration statistics for monthly and annual periods, and mean streamflows for monthly and annual periods. Streamflow is considered to be regulated at streamflow-gaging stations where dams or other large-scale human modifications affect 20 percent or more of the contributing drainage basin. Separate streamflow characteristics are presented for the unregulated and regulated periods of record for streamflow-gaging stations with sufficient data.

  7. Radio frequency electromagnetic field compliance assessment of multi-band and MIMO equipped radio base stations.

    Science.gov (United States)

    Thors, Björn; Thielens, Arno; Fridén, Jonas; Colombi, Davide; Törnevik, Christer; Vermeeren, Günter; Martens, Luc; Joseph, Wout

    2014-05-01

    In this paper, different methods for practical numerical radio frequency exposure compliance assessments of radio base station products were investigated. Both multi-band base station antennas and antennas designed for multiple input multiple output (MIMO) transmission schemes were considered. For the multi-band case, various standardized assessment methods were evaluated in terms of resulting compliance distance with respect to the reference levels and basic restrictions of the International Commission on Non-Ionizing Radiation Protection. Both single frequency and multiple frequency (cumulative) compliance distances were determined using numerical simulations for a mobile communication base station antenna transmitting in four frequency bands between 800 and 2600 MHz. The assessments were conducted in terms of root-mean-squared electromagnetic fields, whole-body averaged specific absorption rate (SAR) and peak 10 g averaged SAR. In general, assessments based on peak field strengths were found to be less computationally intensive, but lead to larger compliance distances than spatial averaging of electromagnetic fields used in combination with localized SAR assessments. For adult exposure, the results indicated that even shorter compliance distances were obtained by using assessments based on localized and whole-body SAR. Numerical simulations, using base station products employing MIMO transmission schemes, were performed as well and were in agreement with reference measurements. The applicability of various field combination methods for correlated exposure was investigated, and best estimate methods were proposed. Our results showed that field combining methods generally considered as conservative could be used to efficiently assess compliance boundary dimensions of single- and dual-polarized multicolumn base station antennas with only minor increases in compliance distances.

  8. Pedestrian movement analysis in transfer station corridor: Velocity-based and acceleration-based

    Science.gov (United States)

    Ji, Xiangfeng; Zhang, Jian; Hu, Yongkai; Ran, Bin

    2016-05-01

    In this paper, pedestrians are classified into aggressive and conservative ones by their temper. Aggressive pedestrians' walking through crowd in transfer station corridor is analyzed. Treating pedestrians as particles, this paper uses the modified social force model (MSFM) as the building block, where forces involve self-driving force, repulsive force and friction force. The proposed model in this paper is a discrete model combining the MSFM and cellular automata (CA) model, where the updating rules of the CA are redefined with MSFM. Due to the continuity of values generated by the MSFM, we use the fuzzy logic to discretize the continuous values into cells pedestrians can move in one step. With the observation that stimulus around pedestrians influences their acceleration directly, an acceleration-based movement model is presented, compared to the generally reviewed velocity-based movement model. In the acceleration-based model, a discretized version of kinematic equation is presented based on the acceleration discretized with fuzzy logic. In real life, some pedestrians would rather keep their desired speed and this is also mimicked in this paper, which is called inertia. Compared to the simple triangular membership function, a trapezoidal membership function and a piecewise linear membership function are used to capture pedestrians' inertia. With the trapezoidal and the piecewise linear membership function, many overlapping scenarios should be carefully handled and Dubois and Prade's four-index method is used to completely describe the relative relationship of fuzzy quantities. Finally, a simulation is constructed to demonstrate the effect of our model.

  9. One4All Cooperative Media Access Strategy in Infrastructure Based Distributed Wireless Networks

    DEFF Research Database (Denmark)

    Zhang, Qi; Fitzek, Frank H.P.; Iversen, Villy Bæk

    2008-01-01

    In this paper we propose the one4all cooperative access strategy to introduce a more efficient media access strategy for wireless networks. The one4all scheme is designed for the infrastructure based distributed wireless network architecture. The basic idea is that mobile devices can form...... a cooperative cluster using their short-range air interface and one device contends the channel for all the devices within the cluster. This strategy reduces the number of mobile devices involved in the collision process for the wireless medium resulting in larger throughput, smaller access delay, and less...... energy consumption. Based on an analytical model, the proposed strategy is compared with the two existing strategies RTS/CTS (request to send/ clear to send) and packet aggregation. The results show that the proposed cooperative scheme has similar throughput performance as packet aggregation and it has...

  10. Research on Multirobot Pursuit Task Allocation Algorithm Based on Emotional Cooperation Factor

    Directory of Open Access Journals (Sweden)

    Baofu Fang

    2014-01-01

    Full Text Available Multirobot task allocation is a hot issue in the field of robot research. A new emotional model is used with the self-interested robot, which gives a new way to measure self-interested robots’ individual cooperative willingness in the problem of multirobot task allocation. Emotional cooperation factor is introduced into self-interested robot; it is updated based on emotional attenuation and external stimuli. Then a multirobot pursuit task allocation algorithm is proposed, which is based on emotional cooperation factor. Combined with the two-step auction algorithm recruiting team leaders and team collaborators, set up pursuit teams, and finally use certain strategies to complete the pursuit task. In order to verify the effectiveness of this algorithm, some comparing experiments have been done with the instantaneous greedy optimal auction algorithm; the results of experiments show that the total pursuit time and total team revenue can be optimized by using this algorithm.

  11. Research on multirobot pursuit task allocation algorithm based on emotional cooperation factor.

    Science.gov (United States)

    Fang, Baofu; Chen, Lu; Wang, Hao; Dai, Shuanglu; Zhong, Qiubo

    2014-01-01

    Multirobot task allocation is a hot issue in the field of robot research. A new emotional model is used with the self-interested robot, which gives a new way to measure self-interested robots' individual cooperative willingness in the problem of multirobot task allocation. Emotional cooperation factor is introduced into self-interested robot; it is updated based on emotional attenuation and external stimuli. Then a multirobot pursuit task allocation algorithm is proposed, which is based on emotional cooperation factor. Combined with the two-step auction algorithm recruiting team leaders and team collaborators, set up pursuit teams, and finally use certain strategies to complete the pursuit task. In order to verify the effectiveness of this algorithm, some comparing experiments have been done with the instantaneous greedy optimal auction algorithm; the results of experiments show that the total pursuit time and total team revenue can be optimized by using this algorithm.

  12. Open-Ended Interaction in Cooperative Pro-to-typing: A Video-based Analysis

    DEFF Research Database (Denmark)

    Bødker, Susanne; Grønbæk, Kaj; Trigg, Randal

    1991-01-01

    that are tied concretely to some current version of the prototype. On the other hand, the users learn more about the potential for change in their work practice, whether computer-based or otherwise. This paper presents the results of a field study of the cooperative prototyping process. The study is based...... and how cooperative prototyping can be successful with users who are reluctant to “play in the future.” The paper also discusses issues in applying video analysis to system design.......Cooperative Prototyping can be characterized as the use and development of prototypes as catalysts during discussions between designers and potential users – the overall intention being one of mutual learning. On the one hand, the designers learn more about the work practices of the users in ways...

  13. Non-cooperative spacecraft pose tracking based on point cloud feature

    Science.gov (United States)

    He, Ying; Liang, Bin; He, Jin; Li, Shunzhi

    2017-10-01

    On-orbit services have been paid more and more attention for its role in spacecraft life-extension, capacity improvement and on-orbit debris removal. As most of on-orbit targets are non-cooperative, relatively accurate pose measurement is very essential for subsequent operations. However, with the rapid development of TriDAR, flash LIDAR and other laser scanning equipment in non-cooperative target measurement, it becomes more imperative to research methods for non-cooperative target pose tracking based on 3D point cloud feature. In this paper, a method for non-cooperative target pose tracking based on point cloud feature is proposed. Firstly, the target is identified using curvature, normal, density and other geometric features of the point cloud. Then the particle filter algorithm is used to recognize the position and orientation of the target being tracked by calculating the similarity of the point cloud features of two adjacent frames. Experimental results showed that the proposed method could effectively identify the features of non-cooperative targets and track their position and attitude.

  14. Exploring the cooperative regimes in an agent-based model: indirect reciprocity vs. selfish incentives

    Science.gov (United States)

    Fort, H.

    2003-08-01

    The self-organization in cooperative regimes in a simple mean-field version of a model based on “selfish” agents which play the Prisoner's Dilemma (PD) game is studied. The agents have no memory and use strategies not based on direct reciprocity nor “tags”. Two variables are assigned to each agent k at time t, measuring its capital C( k; t) and its probability of cooperation p( k; t). At each time step t a pair of agents interact by playing the PD game. These two agents update their probability of cooperation p( k; t) as follows: they compare the profits they made in this interaction δC( k; t) with an estimator ε( k; t) and, if δC( k; t)⩾ ε( k; t), agent i increases its p( k; t) while if δC( k; t)punishment)-are analyzed. It turns out that for all these 24 possibilities, after a transient, the system self-organizes into a stationary state with average equilibrium probability of cooperation p¯∞= constant>0 . Depending on the payoff matrix, there are different equilibrium states characterized by their average probability of cooperation and average equilibrium per capita income ( p¯∞, δC¯∞) .

  15. Gallium Nitride -based Microwave Power Varactors for Wireless Base Station Applications

    Science.gov (United States)

    Lu, Wei

    With the development of wireless communication systems, the demand for providing tunability in the wireless communication circuits becomes more and more intense. Among the technologies, semiconductor varactor is the critical component that is capable of implementing tunable and adaptive characteristics, particularly for the frond-end components of the wireless communication systems. For base station applications, high voltage handling capability, typically of 100 V or greater, high quality factor (Q), typically of above 100 at operation frequency, and high linearity, OIP3 > 65 dBm, are required. This work will mainly discuss in detail the design, fabrication and characterization to achieve the high-voltage high-Q and high-linearity microwave power varactors for wireless base station applications. Some preliminary varactor applications in the test tunable circuits will be demonstrated too. In this dissertation, we first introduce the physics of the semiconductor varactors and the motivation for choosing GaN as the candidate material for this microwave power varactor. Then we elucidate the critical design considerations for achieving high breakdown voltage, high quality factor and high linearity. The novel Schottky barrier engineered design using a thin InGaN surface layer on top of GaN to enhance the breakdown voltage of GaN-based Schottky diodes is therefore introduced. We then show the theoretical and experimental studies on the suppression mechanisms for electron tunneling in the InGaN/GaN Schottky barriers. The detailed material characterization for the InGaN/GaN material system and its application for the enhancement-mode HEMTs are also presented. Next, we discuss the initial device fabrication procedure and the improving methods based on the initial DC and RF measurement results. Thereafter, we report the detailed characterizations of the fabricated devices including the high-voltage I-V and C-V, S-parameters for 1-port and 2-port devices, linearity and

  16. Modelling indoor electromagnetic fields (EMF) from mobile phone base stations for epidemiological studies

    NARCIS (Netherlands)

    Beekhuizen, J.; Vermeulen, R.; van Eijsden, M.; van Strien, R.; Bürgi, A.; Loomans, E.; Guxens, M.; Kromhout, H.; Huss, A.

    2014-01-01

    Radio frequency electromagnetic fields (RF-EMF) from mobile phone base stations can be reliably modelled for outdoor locations, using 3D radio wave propagation models that consider antenna characteristics and building geometry. For exposure assessment in epidemiological studies, however, it is espec

  17. What input data are needed to accurately model electromagnetic fields from mobile phone base stations?

    NARCIS (Netherlands)

    Beekhuizen, Johan; Kromhout, Hans; Bürgi, Alfred; Huss, Anke; Vermeulen, Roel

    2015-01-01

    The increase in mobile communication technology has led to concern about potential health effects of radio frequency electromagnetic fields (RF-EMFs) from mobile phone base stations. Different RF-EMF prediction models have been applied to assess population exposure to RF-EMF. Our study examines what

  18. Design of Three Phase Solar-Based 4.5kw Ac Power Inverter Station

    Directory of Open Access Journals (Sweden)

    Dr.J.C. Onuegbu

    2013-07-01

    Full Text Available The design model of a 4.50Kilowatt, 3-phase, 50 hertz solar-based power generating station was examined by the paper. The power station is a dual source input generating station using 8 series connected 100A, 12V batteries per phase as backup, the solar panels being the main frame. An inverter of 12Volt direct current input voltage was incorporated to supply an output of 3-phase, 220Volts and 50 hertz alternating current. A charging circuit was installed to monitor charging level and to preserve the accumulator’s life span. The paper also looked into the solar-based power station component design model. The batteries therein are back-up and the system will ensure 24-hours reliable power supply. The setup has a normally closed switching relay ready to pickup the auxiliary battery supply within a few milliseconds after the solar source voltage drops below a stipulated level. The three phase a.c. voltage was achieved using standby on-line circuit with cascaded 741-based flip-flop at the base of the transistor drivers of the 3-phase power transformer. This model circuit reduced the load on each phase winding and facilitated reliable and uninterruptible power supply. The delta-wyeconnected transformer will guarantee proper phase shift of 120 degrees that will emulate alternating current voltage similar to the conventional generator voltage.

  19. Risk and Benefit Perceptions of Mobile Phone and Base Station Technology in Bangladesh

    NARCIS (Netherlands)

    Kleef, van E.; Fischer, A.R.H.; Khan, M.; Frewer, L.J.

    2010-01-01

    Research in developed countries showed that many citizens perceive that radio signals transmitted by mobile phones and base stations represent potential health risks. Less research has been conducted in developing countries focused on citizen perceptions of risks and benefits, despite the recent and

  20. Quality Stability of Multi-Station Assembly Process Based on Variation Stream

    Institute of Scientific and Technical Information of China (English)

    WANG Lei; GUO Wei; ZHANG Conghui; ZHAO Jiali

    2007-01-01

    To analyze the physical structure of assembly process and assure product quality, the quality stability of multi-station assembly process was investigated. First, the assembly process was modeled as a one-dimensional discrete variant system by state space equation based on variation stream. Then, the criterion to judge whether the process is stable or not and the index, stability degree, to show the level of stability were proposed by analyzing the bounded-input bounded-output(BIBO) stability of system. Finally, a simulated example of a sheet metal assembly process with three stations, was provided to verify the effectiveness of the proposed method.

  1. The Research and Implementation of Three Stages Traffic Stations Intelligent Monitor Systems Based on GIS

    Science.gov (United States)

    Hong-ying, Chen; Ting, Xiao; WangTao; Jin-yi, He

    This system used three stage intelligent traffic station subsystems to forecast the path on which vehicle will go. First stage subsystem can forecast road node which adjacented to traffic station. Second stage subsystem was designed for bigger area, for example city, the third stage subsystem was for the larger area between city. Second stage subsystem system used A* based on orientation to calculate shortest path, third stage subsystem calculated critical node of a large area. The system can compose dispersed monitor information, forecast vehicle path, dynamic analysis, hierarchical monitor .It played an important role in ITS.

  2. Tectonic Plate Parameters Estimated in the International Terrestrial Reference Frame ITRF2008 Based on SLR Stations

    Directory of Open Access Journals (Sweden)

    Kraszewska Katarzyna

    2016-10-01

    Full Text Available This paper concerns an analysis of the accuracy of estimated parameters Ω(Φ, Λ, ω which define the tectonic plate motions. The study is based on the velocities of station positions published by ITRF2008 for Satellite Laser Ranging (SLR technique. The Eurasian, African, North American and Australian plates were used in the analysis. Influence of the number and location of stations on the plate surface on estimation accuracy of the tectonic plate motion parameters was discussed. The results were compared with the APKIM 2005 IGN model. In general, a remarkable concurrence agreement between our solutions and the APKIM 2005 model was found.

  3. A Fuzzy Logic-Based Approach for Estimation of Dwelling Times of Panama Metro Stations

    Directory of Open Access Journals (Sweden)

    Aranzazu Berbey Alvarez

    2015-04-01

    Full Text Available Passenger flow modeling and station dwelling time estimation are significant elements for railway mass transit planning, but system operators usually have limited information to model the passenger flow. In this paper, an artificial-intelligence technique known as fuzzy logic is applied for the estimation of the elements of the origin-destination matrix and the dwelling time of stations in a railway transport system. The fuzzy inference engine used in the algorithm is based in the principle of maximum entropy. The approach considers passengers’ preferences to assign a level of congestion in each car of the train in function of the properties of the station platforms. This approach is implemented to estimate the passenger flow and dwelling times of the recently opened Line 1 of the Panama Metro. The dwelling times obtained from the simulation are compared to real measurements to validate the approach.

  4. A case-based reasoning approach for estimating the costs of pump station projects

    Directory of Open Access Journals (Sweden)

    Mohamed M. Marzouk

    2011-10-01

    Full Text Available The effective estimation of costs is crucial to the success of construction projects. Cost estimates are used to evaluate, approve and/or fund projects. Organizations use some form of classification system to identify the various types of estimates that may be prepared during the lifecycle of a project. This research presents a parametric-cost model for pump station projects. Fourteen factors have been identified as important to the influence of the cost of pump station projects. A data set that consists of forty-four pump station projects (fifteen water and twenty-nine waste water are collected to build a Case-Based Reasoning (CBR library and to test its performance. The results obtained from the CBR tool are processed and adopted to improve the accuracy of the results. A numerical example is presented to demonstrate the development of the effectiveness of the tool.

  5. Transient Simulations in Hydropower Stations Based on a Novel Turbine Boundary

    Directory of Open Access Journals (Sweden)

    Yanna Liu

    2016-01-01

    Full Text Available Most accidents in hydropower stations happened during transient processes; thus, simulation of these processes is important for station design and safety operation. This study establishes a mathematical model of the transient process in hydropower stations and presents a new method to calculate the hydraulic turbine boundary based on an error function of the rotational speed. The mathematical derivation shows that the error function along the equal-opening characteristic curve is monotonic and has opposite signs at the two sides, which means that a unique solution exists to make the error function null. Thus, iteration of the transient simulation is unique and monotonous, which avoids iterative convergence or false solution and improves the solution efficiency compared with traditional methods. Simulation of an engineering case illustrates that the results obtained by the error function are reasonable. Then, the accuracy and feasibility of the mathematical model using the proposed solution are verified by comparison with model and field tests.

  6. Cooperative Hurricane Network Obs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Observations from the Cooperative Hurricane Reporting Network (CHURN), a special network of stations that provided observations when tropical cyclones approached the...

  7. Public safety assessment of electromagnetic radiation exposure from mobile base stations.

    Science.gov (United States)

    Alhekail, Z O; Hadi, M A; Alkanhal, M A

    2012-09-01

    Exposure of the general public to electromagnetic radiation originating from randomly selected GSM/WCDMA base stations in Riyadh, Kingdom of Saudi Arabia has been assessed in the context of the International Commission on Non-Ionising Radiation Protection (ICNIRP) guidelines. The purpose of the measurement was to record the maximum power density of signals to estimate possible worst case exposure at each measurement location. These power density measurements were carried out at 60 mobile base stations located in different regions of the city. For each of these sites, three sectors were operational, yielding a total of 180 sectors. Two positions were identified per site with the greatest power density values. Exposures from these base stations were generally found to be in the range of 0.313 to 0.00000149% of the ICNIRP general public reference level, and the greatest exposure near any of the base stations was 21.96 mW m(-2) for a wideband measurement in the 75-3000 MHz frequency range. Analysis of the measured data reveals several trends for different mobile bands with respect to maximum exposure in those locations. Additionally, a simplified calculation method for the electromagnetic fields was used to compare calculated and the measured data. It was determined, on the basis of both results of the measurements and calculations carried out for these selected base stations, that members of the public would not be exposed to in excess of a small fraction of the ICNIRP guidelines at any of those sites. These are first such measurements to be made in the Middle East and provide assurance that exposures in this region of the world do not seem to be any greater than elsewhere.

  8. 基于PMAC的MACRO Station 的应用%The Application of MACRO Station Based on PMAC

    Institute of Scientific and Technical Information of China (English)

    王宏; 王斌; 弓清忠; 祁玉宁

    2004-01-01

    介绍了PMAC运动控制器及MACRO Station(宏运动控制站)的概念.阐述MACRO Station的设置及映射的建立,结合轧辊磨床专用数控系统的建立,介绍MACRO Station的应用及其实际意义.

  9. Cooperative co-evolution based distributed path planning of multiple mobile robots

    Institute of Scientific and Technical Information of China (English)

    WANG Mei; WU Tie-jun

    2005-01-01

    This paper proposes novel multiple-mobile-robot collision avoidance path planning based on cooperative co-evolution,which can be executed fully distributed and in parallel. A real valued co-evolutionary algorithm is developed to coordinate the movement of multiple robots in 2D world, avoiding C-space or grid net searching. The collision avoidance is achieved by cooperatively co-evolving segments of paths and the time interval to pass them. Methods for constraint handling, which are developed for evolutionary algorithm, make the path planning easier. The effectiveness of the algorithm is demonstrated on a number of 2Dpath planning problems.

  10. Network-based criterion for the success of cooperation in an evolutionary prisoner's dilemma.

    Science.gov (United States)

    Devlin, Stephen; Treloar, Thomas

    2012-08-01

    We consider an evolutionary prisoner's dilemma on a random network. We introduce a simple quantitative network-based parameter and show that it effectively predicts the success of cooperation in simulations on the network. The criterion is shown to be accurate on a variety of networks with degree distributions ranging from regular to Poisson to scale free. The parameter allows for comparisons of random networks regardless of their underlying topology. Finally, we draw analogies between the criterion for the success of cooperation introduced here and existing criteria in other contexts.

  11. Performance Analysis of Observation Based Cooperation Enforcement in Ad Hoc Networks

    CERN Document Server

    Ghandar, Abeer; Fayed, Zaky Taha

    2012-01-01

    Node misbehavior due to selfish or malicious behavior could significantly degrade the performance of MANET because most existing routing protocols in MANET aim to find the most efficient path. Overhearing and reputation based cooperation schemes have been used to detect and isolate the misbehaving nodes as well as to force them to cooperate. Performance analysis has been done for the network traffic using OCEAN over DSR on ns2 while considering the low energy levels for mobile nodes. Throughput, energy level, routing packets and normalized routing overhead are analyzed for OCEAN and normal DSR to show the impact of OCEAN on the overall network performance.

  12. Subject Combination and Electrode Selection in Cooperative Brain-Computer Interface Based on Event Related Potentials

    Directory of Open Access Journals (Sweden)

    Hubert Cecotti

    2014-04-01

    Full Text Available New paradigms are required in Brain-Computer Interface (BCI systems for the needs and expectations of healthy people. To solve this issue, we explore the emerging field of cooperative BCIs, which involves several users in a single BCI system. Contrary to classical BCIs that are dependent on the unique subject’s will, cooperative BCIs are used for problem solving tasks where several people shall be engaged by sharing a common goal. Similarly as combining trials over time improves performance, combining trials across subjects can significantly improve performance compared with when only a single user is involved. Yet, cooperative BCIs may only be used in particular settings, and new paradigms must be proposed to efficiently use this approach. The possible benefits of using several subjects are addressed, and compared with current single-subject BCI paradigms. To show the advantages of a cooperative BCI, we evaluate the performance of combining decisions across subjects with data from an event-related potentials (ERP based experiment where each subject observed the same sequence of visual stimuli. Furthermore, we show that it is possible to achieve a mean AUC superior to 0.95 with 10 subjects and 3 electrodes on each subject, or with 4 subjects and 6 electrodes on each subject. Several emerging challenges and possible applications are proposed to highlight how cooperative BCIs could be efficiently used with current technologies and leverage BCI applications.

  13. Subject combination and electrode selection in cooperative brain-computer interface based on event related potentials.

    Science.gov (United States)

    Cecotti, Hubert; Rivet, Bertrand

    2014-04-30

    New paradigms are required in Brain-Computer Interface (BCI) systems for the needs and expectations of healthy people. To solve this issue, we explore the emerging field of cooperative BCIs, which involves several users in a single BCI system. Contrary to classical BCIs that are dependent on the unique subject's will, cooperative BCIs are used for problem solving tasks where several people shall be engaged by sharing a common goal. Similarly as combining trials over time improves performance, combining trials across subjects can significantly improve performance compared with when only a single user is involved. Yet, cooperative BCIs may only be used in particular settings, and new paradigms must be proposed to efficiently use this approach. The possible benefits of using several subjects are addressed, and compared with current single-subject BCI paradigms. To show the advantages of a cooperative BCI, we evaluate the performance of combining decisions across subjects with data from an event-related potentials (ERP) based experiment where each subject observed the same sequence of visual stimuli. Furthermore, we show that it is possible to achieve a mean AUC superior to 0.95 with 10 subjects and 3 electrodes on each subject, or with 4 subjects and 6 electrodes on each subject. Several emerging challenges and possible applications are proposed to highlight how cooperative BCIs could be efficiently used with current technologies and leverage BCI applications.

  14. Cartalk 2000: development of a co-operative ADAS based on vehicle-to-vehicle communication

    NARCIS (Netherlands)

    Morsink, P.L.J.; Hallouzi, R.; Dagli, I.; Cseh, C.; Schäfers, L.; Nelisse, M.W.; Bruin, D. de

    2003-01-01

    Advanced Driver Assistance Systems (ADAS) benefit from using vehicle-to-vehicle communication. In the 5th framework EC project CarTALK2000 co-operative ADAS are designed, tested and evaluated with respect to increasing traffic safety, efficiency and driving comfort. Communication based longitudinal

  15. Impact assessment for cooperative urban traffic management applications based on microscopic traffic flow simulation

    NARCIS (Netherlands)

    Lüßmann, J.; Vreeswijk, J.; Katwijk, R. van; Blokpoel, R.; Fullerton, M.

    2014-01-01

    The EU FP7 project eCoMove created an integrated solution for more energy efficient road transport based on cooperative technology. The project's core concept assumed that there is theoretical minimum energy consumption achievable with the "perfect eco-driver" travelling through the "perfectly

  16. Successful Group Work: Using Cooperative Learning and Team-Based Learning in the Classroom

    Science.gov (United States)

    Grant-Vallone, E. J.

    2011-01-01

    This research study examined student perceptions of group experiences in the classroom. The author used cooperative learning and team-based learning to focus on three characteristics that are critical for the success of groups: structure of activities, relationships of group members, and accountability of group members. Results indicated that…

  17. The Effects of Jigsaw Technique Based on Cooperative Learning on Prospective Science Teachers' Science Process Skill

    Science.gov (United States)

    Karacop, Ataman; Diken, Emine Hatun

    2017-01-01

    The purpose of this study is to investigate the effects of laboratory approach based on jigsaw method with cooperative learning and confirmatory laboratory approach on university students' cognitive process development in Science teaching laboratory applications, and to determine the opinions of the students on applied laboratory methods. The…

  18. Raising Awareness of Assistive Technology in Older Adults through a Community-Based, Cooperative Extension Program

    Science.gov (United States)

    Sellers, Debra M.; Markham, Melinda Stafford

    2012-01-01

    The Fashion an Easier Lifestyle with Assistive Technology (FELAT) curriculum was developed as a needs-based, community educational program provided through a state Cooperative Extension Service. The overall goal for participants was to raise awareness of assistive technology. Program evaluation included a postassessment and subsequent interview to…

  19. Inquiry and Groups: Student Interactions in Cooperative Inquiry-Based Science

    Science.gov (United States)

    Woods-McConney, Amanda; Wosnitza, Marold; Sturrock, Keryn L.

    2016-01-01

    Science education research has recommended cooperative inquiry based science in the primary science context for more than two decades but after more than 20 years, student achievement in science has not substantially improved. This study, through direct observation and analysis, investigated content-related student interactions in an authentic…

  20. Inquiry and Groups: Student Interactions in Cooperative Inquiry-Based Science

    Science.gov (United States)

    Woods-McConney, Amanda; Wosnitza, Marold; Sturrock, Keryn L.

    2016-01-01

    Science education research has recommended cooperative inquiry based science in the primary science context for more than two decades but after more than 20 years, student achievement in science has not substantially improved. This study, through direct observation and analysis, investigated content-related student interactions in an authentic…

  1. A Model of Solid Waste Management Based Multilateral Co-Operation in Semi-Urban Community

    Science.gov (United States)

    Kanchanabhandhu, Chanchai; Woraphong, Seree

    2016-01-01

    The purpose of this research was to construct a model of solid waste management based on multilateral cooperation in semi-urban community. Its specific objectives were to 1) study the solid waste situation and involvement of community in the solid waste management in Wangtaku Sub-district, Muang District, Nakhon Pathom Province; 2) construct a…

  2. A Journal-Club-Based Class that Promotes Active and Cooperative Learning of Biology

    Science.gov (United States)

    Kitazono, Ana A.

    2010-01-01

    A journal-club-based class has been developed to promote active and cooperative learning and expose seniors in biochemistry and cellular molecular biology to recent research in the field. Besides giving oral presentations, students also write three papers: one discussing an article of their own choosing and two, discussing articles presented by…

  3. Experimental Investigation of Cooperative Schemes on a Real-Time DSP-Based Testbed

    Directory of Open Access Journals (Sweden)

    Per Zetterberg

    2009-01-01

    Full Text Available Experimental results on the well-known cooperating relaying schemes, amplify-and-forward (AF, detect-and-forward (DF, cooperative maximum ratio combining (CMRC, and distributed space-time coding (DSTC, are presented in this paper. A novel relaying scheme named “selection relaying” (SR, in which one of two relays are selected base on path-loss, is also tested. For all schemes except AF receive antenna diversity is as an option which can be switched on or off. For DF and DSTC a feature “selective” where the relay only forwards frames with a receive SNR above 6 dB is introduced. In our measurements, all cooperative relaying schemes above increase the coverage area as compared with direct transmission. The features “antenna diversity” and “selective” improve the performance. Good performance is obtained with CMRC, DSTC, and SR.

  4. Cooperative Control Based on Absolute Positional Information of Grasped Object in Multiple Mobile Manipulators

    Science.gov (United States)

    Sugawara, Toshiharu; Murakami, Toshiyuki

    This paper describes a control strategy to realize grasping and cooperative motion in multiple mobile manipulators. In the general approach, the stable grasping motion is well realized, but the emergent motion such as the obstacle avoidance motion and the collision avoidance motion among the robots are not taken into account in the cooperative motion of multiple mobile manipulators. In the practical application, however, the above issue is important to realize an adaptive and sophisticated motion. The proposed approach introduces the null space motion based on the grasping matrix and the absolute position of target object in the grasping motion of the manipulator. In this case, each motion of mobile manipulator is given independently of the grasping and the cooperative motion, and the emergent motion is determined arbitrary. This is one of the remarkable features of the proposed strategy. Several numerical and experimental results show the validity of the proposed approach.

  5. Efficient Relay Selection Scheme based on Fuzzy Logic for Cooperative Communication

    Directory of Open Access Journals (Sweden)

    Shakeel Ahmad Waqas

    2016-11-01

    Full Text Available The performance of cooperative network can be increased by using relay selection technique. Therefore, interest in relay selection is sloping upward. We proposed two new relay selection schemes based on fuzzy logic for dual hop cooperative communication. These relay selection schemes require SNR (signal to noise ratio, cooperative gain and channel gain as input fuzzy parameters for selection of best relay. The performance of first proposed relay selection scheme is evaluated in term of BER (bit error rate in Nakagami, Rician and Rayleigh fading channels. In second proposed relay selection scheme, threshold is used with the objective to minimize the power consumption and channel estimation load. Its performance is analyzed in term of BER, number of active relays and load of number of channel estimations.

  6. Study on Cooperative Mechanism of Prefabricated Producers Based on Evolutionary Game Theory

    Directory of Open Access Journals (Sweden)

    Tongyao Feng

    2017-01-01

    Full Text Available Good cooperation mechanism is an important guarantee for the advancement of industrialization construction. To strengthen the partnership between producers, we analyze the behavior evolution trend of both parties using an evolutionary game theory. Based on the original model, the mechanism of coordination and cooperation between prefabricated producers is explained under the condition of punishment and incentive. The results indicate that stable evolutionary strategies exist under both cooperation and noncooperation, and the evolutionary results are influenced by the initial proportion of both decision-making processes. The government can support the production enterprises to establish a solid partnership through effective punishment and incentive mechanisms to reduce the initial cost in the supply chain of prefabricated construction, resulting in a win-win situation.

  7. Emergence of Cooperative Behavior based on Learning and Evolution in Collective Autonomous Mobile Robots

    Energy Technology Data Exchange (ETDEWEB)

    Jun, H.B.; Sim, K.B. [Chungang University, Seoul (Korea, Republic of)

    1998-12-01

    In this paper, we propose a behavior learning algorithm of the collective autonomous mobile robots based on the reinforcement learning and conditional evolution. The cooperative behavior is a high level phenomenon observed in the society of social animals and, recently the emergence of cooperative behavior in collective autonomous mobile robots becomes an interesting field in artificial life. In our system each robot with simple behavior strategies can adapt to its environment by means of the reinforcement learning. The internal reinforcement signal for the reinforcement learning is generated by fuzzy interference engine, and dynamic recurrent neural networks are used as an action generation module. We propose conditional evolution for the emergence of cooperative behavior. The evolutionary conditions are spatio-temporal limitations to the occurrence of genetic operations. We show the validity of the proposed learning and evolutionary algorithm through several computer simulations. (author). 22 refs., 9 figs.

  8. Cooperation in Carrier Sense Based Wireless Ad Hoc Networks - Part II: Proactive Schemes

    CERN Document Server

    Munari, Andrea; Zorzi, Michele

    2012-01-01

    This work is the second of a two-part series of papers on the effectiveness of cooperative techniques in non-centralized carrier sense-based ad hoc wireless networks. While Part I extensively discussed reactive cooperation, characterized by relayed transmissions triggered by failure events at the intended receiver, Part II investigates in depth proactive solutions, in which the source of a packet exploits channel state information to preemptively coordinate with relays in order to achieve the optimal overall rate to the destination. In particular, this work shows by means of both analysis and simulation that the performance of reactive cooperation is reduced by the intrinsic nature of the considered medium access policy, which biases the distribution of the available relays, locating them in unfavorable positions for rate optimization. Moreover, the highly dynamic nature of interference that characterizes non-infrastructured ad hoc networks is proved to hamper the efficacy and the reliability of preemptively ...

  9. Measuring prosodic alignment in cooperative task-based conversations

    NARCIS (Netherlands)

    Truong, Khiet P.; Heylen, Dirk

    2012-01-01

    In this paper, we investigate prosodic alignment in task-based conversations. We use the HCRC Map Task Corpus and investigate how familiarity affects prosodic alignment and how task success is related to prosodic alignment. A variety of existing alignment measures is used and applied to our data. In

  10. Memoryless cooperative graph search based on the simulated annealing algorithm

    Institute of Scientific and Technical Information of China (English)

    Hou Jian; Yan Gang-Feng; Fan Zhen

    2011-01-01

    We have studied the problem of reaching a globally optimal segment for a graph-like environment with a single or a group of autonomous mobile agents. Firstly, two efficient simulated-annealing-like algorithms are given for a single agent to solve the problem in a partially known environment and an unknown environment, respectively. It shows that under both proposed control strategies, the agent will eventually converge to a globally optimal segment with probability 1Secondly, we use multi-agent searching to simultaneously reduce the computation complexity and accelerate convergence based on the algorithms we have given for a single agent. By exploiting graph partition, a gossip consensus method based scheme is presented to update the key parameter-radius of the graph, ensuring that the agents spend much less time finding a globally optimal segment.

  11. Resource Allocation for Selection-Based Cooperative OFDM Networks

    CERN Document Server

    Hosseini, Kianoush

    2011-01-01

    This paper considers resource allocation to achieve max-min fairness in a selection-based orthogonal frequency division multiplexing network wherein source nodes are assisted by fixed decode-and-forward relays. Crucial design questions such as whether to relay, relay assignment and power allocation form a combinatorial problem with exponential solution complexity. The first set of problems assume perfect source-relay channels and that sources distribute power equally across subcarriers. The solutions based on these simplifications help illustrate our general methodology and also why these solutions provide tight bounds. We then formulate the general problem of transmission strategy selection, relay assignment, and power allocation at the sources and relays considering all communication channels, i.e., imperfect source-relay channels. In both sets of problems, transmissions over subcarriers are assumed to be independent. Given the attendant problems of synchronization and the implementation using a FFT/IFFT pa...

  12. Mining Learning Social Networks for Cooperative Learning with Appropriate Learning Partners in a Problem-Based Learning Environment

    Science.gov (United States)

    Chen, Chih-Ming; Chang, Chia-Cheng

    2014-01-01

    Many studies have identified web-based cooperative learning as an increasingly popular educational paradigm with potential to increase learner satisfaction and interactions. However, peer-to-peer interaction often suffers barriers owing to a failure to explore useful social interaction information in web-based cooperative learning environments.…

  13. Mining Learning Social Networks for Cooperative Learning with Appropriate Learning Partners in a Problem-Based Learning Environment

    Science.gov (United States)

    Chen, Chih-Ming; Chang, Chia-Cheng

    2014-01-01

    Many studies have identified web-based cooperative learning as an increasingly popular educational paradigm with potential to increase learner satisfaction and interactions. However, peer-to-peer interaction often suffers barriers owing to a failure to explore useful social interaction information in web-based cooperative learning environments.…

  14. The Effects of Inquiry-Based Computer Simulation with Cooperative Learning on Scientific Thinking and Conceptual Understanding of Gas Laws

    Science.gov (United States)

    Abdullah, Sopiah; Shariff, Adilah

    2008-01-01

    The purpose of the study was to investigate the effects of inquiry-based computer simulation with heterogeneous-ability cooperative learning (HACL) and inquiry-based computer simulation with friendship cooperative learning (FCL) on (a) scientific reasoning (SR) and (b) conceptual understanding (CU) among Form Four students in Malaysian Smart…

  15. Integrated base stations and a method of transmitting data units in a communications system for mobile devices

    NARCIS (Netherlands)

    Bosch, H.G.P.; Mullender, Sape J.; Narlikar, G.J.; Samuel, L.G.; Yagati, L.N.

    2006-01-01

    Integrated base stations and a method of transmitting data units in a communications system for mobile devices. In one embodiment, an integrated base station includes a communications processor having a protocol stack configured with a media access control layer and a physical layer.

  16. A microeconomic-based framework for green cooperative communications

    KAUST Repository

    Bonello, Nicholas

    2011-05-01

    The global concern on environmental issues is placing its mark on all sectors of the society, including of course, the wireless telecommunications industry. In this paper, we develop a microeconomic-based green radio framework in which a network operator shifts some of its responsibilities towards the intended destination to one of these inactive end-users with the specific intention of reducing the transmitted power of its source nodes and the incurred costs. Our results disclose up to 70% energy savings and up to 65% cost savings over the direct transmission benchmarker, when selecting from approximately 50 eligible relays in the scenario portrayed by the UMTS Rel. 99 standard. © 2011 IEEE.

  17. Cooperation-based Ant Colony Algorithm in WSN

    Directory of Open Access Journals (Sweden)

    Jianbin Xue

    2013-04-01

    Full Text Available This paper proposed a routing algorithm based on ant colony algorithm. The traditional ant colony algorithm updates pheromone according to the path length, to get the shortest path from the initial node to destination node. But MIMO system is different from the SISO system. The distance is farther but the energy is not bigger. Similarly, the closer the distance, the smaller the energy is not necessarily. So need to select the path according to the energy consumption of the path. This paper is based on the energy consumption to update the pheromone which from the cluster head node to the next hop node. Then, can find a path which the communication energy consumption is least. This algorithm can save more energy consumption of the network. The simulation results of MATLAB show that the path chosen by the algorithm is better than the simple ant colony algorithm, and the algorithm can save the network energy consumption better and can prolong the life cycle of the network.

  18. A Cooperative Approach to Virtual Machine Based Fault Injection

    Energy Technology Data Exchange (ETDEWEB)

    Naughton III, Thomas J [ORNL; Engelmann, Christian [ORNL; Vallee, Geoffroy R [ORNL; Aderholdt, William Ferrol [ORNL; Scott, Stephen L [Tennessee Technological University (TTU)

    2017-01-01

    Resilience investigations often employ fault injection (FI) tools to study the effects of simulated errors on a target system. It is important to keep the target system under test (SUT) isolated from the controlling environment in order to maintain control of the experiement. Virtual machines (VMs) have been used to aid these investigations due to the strong isolation properties of system-level virtualization. A key challenge in fault injection tools is to gain proper insight and context about the SUT. In VM-based FI tools, this challenge of target con- text is increased due to the separation between host and guest (VM). We discuss an approach to VM-based FI that leverages virtual machine introspection (VMI) methods to gain insight into the target s context running within the VM. The key to this environment is the ability to provide basic information to the FI system that can be used to create a map of the target environment. We describe a proof- of-concept implementation and a demonstration of its use to introduce simulated soft errors into an iterative solver benchmark running in user-space of a guest VM.

  19. On cooperative and efficient overlay network evolution based on a group selection pattern.

    Science.gov (United States)

    Wang, Yufeng; Nakao, Akihiro

    2010-06-01

    In overlay networks, the interplay between network structure and dynamics remains largely unexplored. In this paper, we study dynamic coevolution between individual rational strategies (cooperative or defect) and the overlay network structure, that is, the interaction between peer's local rational behaviors and the emergence of the whole network structure. We propose an evolutionary game theory (EGT)-based overlay topology evolution scheme to drive a given overlay into the small-world structure (high global network efficiency and average clustering coefficient). Our contributions are the following threefold: From the viewpoint of peers' local interactions, we explicitly consider the peer's rational behavior and introduce a link-formation game to characterize the social dilemma of forming links in an overlay network. Furthermore, in the evolutionary link-formation phase, we adopt a simple economic process: Each peer keeps one link to a cooperative neighbor in its neighborhood, which can slightly speed up the convergence of cooperation and increase network efficiency; from the viewpoint of the whole network structure, our simulation results show that the EGT-based scheme can drive an arbitrary overlay network into a fully cooperative and efficient small-world structure. Moreover, we compare our scheme with a search-based economic model of network formation and illustrate that our scheme can achieve the experimental and analytical results in the latter model. In addition, we also graphically illustrate the final overlay network structure; finally, based on the group selection model and evolutionary set theory, we theoretically obtain the approximate threshold of cost and draw the conclusion that the small value of the average degree and the large number of the total peers in an overlay network facilitate the evolution of cooperation.

  20. A Game Theoretic Framework for Green HetNets Using D2D Traffic Offload and Renewable Energy Powered Base Stations

    KAUST Repository

    Yaacoub, Elias

    2015-08-26

    This chapter investigates the interplay between cooperative device-to-device (D2D) communications and green communications in LTE heterogeneous networks (HetNets). Two game theoretic concepts are studied and analyzed in order to perform dynamic HetNet base station (BS) on/off switching. The first approach is a coalition-based method whereas the second is based on the Nash bargaining solution. Afterwards, a method for coupling the BS on/off switching approach with D2D collaborative communications is presented and shown to lead to increased energy efficiency. The savings are additionally increased when a portion of the small cell BSs in a HetNet are powered by renewable energy sources. Different utility functions, modeling the game theoretic framework governing the energy consumption balance between the cellular network and the mobile terminals (MTs), are proposed and compared, and their impact on MT quality of service (QoS) is analyzed.

  1. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station antenna masts.

    Science.gov (United States)

    Koprivica, Mladen; Neskovic, Natasa; Neskovic, Aleksandar; Paunovic, George

    2014-01-01

    As a result of dense installations of public mobile base station, additional electromagnetic radiation occurs in the living environment. In order to determine the level of radio-frequency radiation generated by base stations, extensive electromagnetic field strength measurements were carried out for 664 base station locations. Base station locations were classified into three categories: indoor, masts and locations with installations on buildings. Having in mind the large percentage (47 %) of sites with antenna masts, a detailed analysis of this location category was performed, and the measurement results were presented. It was concluded that the total electric field strength in the vicinity of base station antenna masts in no case exceeded 10 V m(-1), which is quite below the International Commission on Non-Ionizing Radiation Protection reference levels. At horizontal distances >50 m from the mast bottom, the median and maximum values were <1 and 2 V m(-1), respectively.

  2. Cooperation in memory-based prisoner's dilemma game on interdependent networks

    Science.gov (United States)

    Luo, Chao; Zhang, Xiaolin; Liu, Hong; Shao, Rui

    2016-05-01

    Memory or so-called experience normally plays the important role to guide the human behaviors in real world, that is essential for rational decisions made by individuals. Hence, when the evolutionary behaviors of players with bounded rationality are investigated, it is reasonable to make an assumption that players in system are with limited memory. Besides, in order to unravel the intricate variability of complex systems in real world and make a highly integrative understanding of their dynamics, in recent years, interdependent networks as a comprehensive network structure have obtained more attention in this community. In this article, the evolution of cooperation in memory-based prisoner's dilemma game (PDG) on interdependent networks composed by two coupled square lattices is studied. Herein, all or part of players are endowed with finite memory ability, and we focus on the mutual influence of memory effect and interdependent network reciprocity on cooperation of spatial PDG. We show that the density of cooperation can be significantly promoted within an optimal region of memory length and interdependent strength. Furthermore, distinguished by whether having memory ability/external links or not, each kind of players on networks would have distinct evolutionary behaviors. Our work could be helpful to understand the emergence and maintenance of cooperation under the evolution of memory-based players on interdependent networks.

  3. A strategic conflict avoidance approach based on cooperative coevolutionary with the dynamic grouping strategy

    Science.gov (United States)

    Guan, Xiangmin; Zhang, Xuejun; Wei, Jian; Hwang, Inseok; Zhu, Yanbo; Cai, Kaiquan

    2016-07-01

    Conflict avoidance plays a crucial role in guaranteeing the safety and efficiency of the air traffic management system. Recently, the strategic conflict avoidance (SCA) problem has attracted more and more attention. Taking into consideration the large-scale flight planning in a global view, SCA can be formulated as a large-scale combinatorial optimisation problem with complex constraints and tight couplings between variables, which is difficult to solve. In this paper, an SCA approach based on the cooperative coevolution algorithm combined with a new decomposition strategy is proposed to prevent the premature convergence and improve the search capability. The flights are divided into several groups using the new grouping strategy, referred to as the dynamic grouping strategy, which takes full advantage of the prior knowledge of the problem to better deal with the tight couplings among flights through maximising the chance of putting flights with conflicts in the same group, compared with existing grouping strategies. Then, a tuned genetic algorithm (GA) is applied to different groups simultaneously to resolve conflicts. Finally, the high-quality solutions are obtained through cooperation between different groups based on cooperative coevolution. Simulation results using real flight data from the China air route network and daily flight plans demonstrate that the proposed algorithm can reduce the number of conflicts and the average delay effectively, outperforming existing approaches including GAs, the memetic algorithm, and the cooperative coevolution algorithms with different well-known grouping strategies.

  4. Cooperative Caching in Mobile Ad Hoc Networks Based on Data Utility

    Directory of Open Access Journals (Sweden)

    Narottam Chand

    2007-01-01

    Full Text Available Cooperative caching, which allows sharing and coordination of cached data among clients, is a potential technique to improve the data access performance and availability in mobile ad hoc networks. However, variable data sizes, frequent data updates, limited client resources, insufficient wireless bandwidth and client's mobility make cache management a challenge. In this paper, we propose a utility based cache replacement policy, least utility value (LUV, to improve the data availability and reduce the local cache miss ratio. LUV considers several factors that affect cache performance, namely access probability, distance between the requester and data source/cache, coherency and data size. A cooperative cache management strategy, Zone Cooperative (ZC, is developed that employs LUV as replacement policy. In ZC one-hop neighbors of a client form a cooperation zone since the cost for communication with them is low both in terms of energy consumption and message exchange. Simulation experiments have been conducted to evaluate the performance of LUV based ZC caching strategy. The simulation results show that, LUV replacement policy substantially outperforms the LRU policy.

  5. A NASA/RAE cooperation in the development of a real-time knowledge based autopilot

    Science.gov (United States)

    Daysh, Colin; Corbin, Malcolm; Butler, Geoff; Duke, Eugene L.; Belle, Steven D.; Brumbaugh, Randal W.

    1991-01-01

    As part of a US/UK cooperative aeronautical research program, a joint activity between NASA-Ames and the Royal Aerospace Establishment on Knowledge Based Systems (KBS) was established. This joint activity is concerned with tools and techniques for the implementation and validation of real-time KBS. The proposed next stage of the research is described, in which some of the problems of implementing and validating a Knowledge Based Autopilot (KBAP) for a generic high performance aircraft will be studied.

  6. A NASA/RAE cooperation in the development of a real-time knowledge based autopilot

    Science.gov (United States)

    Daysh, Colin; Corbin, Malcolm; Butler, Geoff; Duke, Eugene L.; Belle, Steven D.; Brumbaugh, Randal W.

    1991-01-01

    As part of a US/UK cooperative aeronautical research program, a joint activity between NASA-Ames and the Royal Aerospace Establishment on Knowledge Based Systems (KBS) was established. This joint activity is concerned with tools and techniques for the implementation and validation of real-time KBS. The proposed next stage of the research is described, in which some of the problems of implementing and validating a Knowledge Based Autopilot (KBAP) for a generic high performance aircraft will be studied.

  7. Measuring sustainability based upon various perspectives: a case study of a hill station in Southeast Asia.

    Science.gov (United States)

    Estoque, Ronald C; Murayama, Yuji

    2014-11-01

    A hill station is a town or city situated in mountain regions in the tropics founded during the western colonization in the nineteenth and early twentieth centuries. Hill stations have moderate temperatures, and are known for their relatively good natural environments, which generate valuable ecosystem services that benefit the local population. However, rapid urbanization threatens the sustainability of these areas. This study evaluates the sustainability of the urbanization process of Baguio City, a hill station city in Southeast Asia and the summer capital of the Philippines, by determining the relationship between its velocity of urbanization and velocity of urban sustainability based upon various perspectives. From an equal weight perspective (of the triple bottom line of sustainability components, namely environmental, social, and economic) and a pro-economic perspective, the results revealed that the urbanization of Baguio City has been moving toward a "sustainable urbanization." However, from the environmental and eco-sustainable human development perspectives, the results indicated that it has been moving toward an "unsustainable urbanization." The paper discusses the implications of the findings for the planning of sustainable development for Baguio City, including some critical challenges in sustainability assessment and the applicability of the framework used for future sustainability assessments of the other hill stations in Southeast Asia.

  8. Interference Cancellation in Cooperative CDMA Networks

    Directory of Open Access Journals (Sweden)

    A. Rajeswari

    2011-01-01

    Full Text Available The wireless communication networks are subjected to multi access interference and multipath fading. To minimize the interference cancellation in CDMA networks, multiple user detection schemes and cooperative communication networks are used. consider the uplink of a cooperative CDMA network, where users cooperate by relaying each other’s messages to the base station. When spreading waveforms are not orthogonal, multiple access interference (MAI exists at the relays and the destination, causing cooperative diversity gains to diminish. To overcome this problem, we integrate various multiuser detection (MUD schemes to mitigate MAI in achieving the full advantages of cooperation. Specifically, the relay-assisted decorrelating multiuser detector (RADMUD is proposed to separate interfering signals at the destination with the help of precoding at the relays along with pre-whitening at the destination. In this paper we examined the BER performance of various MUD schemes are analyzed and compared with cooperative system. The advantages of RAD-MUD with co-operative communication shows better BER performance compared with non co-operative wireless communication system and other existing cooperative MUD schemes are also shown through MATLAB Simulations.

  9. Analyzing mobile WiMAX base station deployment under different frequency planning strategies

    Science.gov (United States)

    Salman, M. K.; Ahmad, R. B.; Ali, Ziad G.; Aldhaibani, Jaafar A.; Fayadh, Rashid A.

    2015-05-01

    The frequency spectrum is a precious resource and scarce in the communication markets. Therefore, different techniques are adopted to utilize the available spectrum in deploying WiMAX base stations (BS) in cellular networks. In this paper several types of frequency planning techniques are illustrated, and a comprehensive comparative study between conventional frequency reuse of 1 (FR of 1) and fractional frequency reuse (FFR) is presented. These techniques are widely used in network deployment, because they employ universal frequency (using all the available bandwidth) in their base station installation/configuration within network system. This paper presents a network model of 19 base stations in order to be employed in the comparison of the aforesaid frequency planning techniques. Users are randomly distributed within base stations, users' resource mapping and their burst profile selection are based on the measured signal to interference plus-noise ratio (SINR). Simulation results reveal that the FFR has advantages over the conventional FR of 1 in various metrics. 98 % of downlink resources (slots) are exploited when FFR is applied, whilst it is 81 % at FR of 1. Data rate of FFR has been increased to 10.6 Mbps, while it is 7.98 Mbps at FR of 1. The spectral efficiency is better enhanced (1.072 bps/Hz) at FR of 1 than FFR (0.808 bps/Hz), since FR of 1 exploits all the Bandwidth. The subcarrier efficiency shows how many data bits that can be carried by subcarriers under different frequency planning techniques, the system can carry more data bits under FFR (2.40 bit/subcarrier) than FR of 1 (1.998 bit/subcarrier). This study confirms that FFR can perform better than conventional frequency planning (FR of 1) which made it a strong candidate for WiMAX BS deployment in cellular networks.

  10. Exposure to superfluous information reduces cooperation and increases antisocial punishment in reputation-based interactions

    Directory of Open Access Journals (Sweden)

    Miguel edos Santos

    2014-08-01

    Full Text Available Human cooperation is often based on reputation gained from previous interactions with third parties. Such reputation can be built on generous or punitive actions, and both, one’s own reputation and the reputation of others have been shown to influence decision making in experimental games that control for confounding variables. Here we test how reputation-based cooperation and punishment react to disruption of the cognitive processing in different kinds of helping games with observers. Saying a few superfluous words before each interaction was used to possibly interfere with working memory. In a first set of experiments, where reputation could only be based on generosity, the disruption reduced the frequency of cooperation and lowered mean final payoffs. In a second set of experiments where reputation could only be based on punishment, the disruption increased the frequency of antisocial punishment (i.e. of punishing those who helped and reduced the frequency of punishing defectors. Our findings suggest that working memory can easily be constraining in reputation-based interactions within experimental games, even if these games are based on a few simple rules with a visual display that provides all the information the subjects need to play the strategies predicted from current theory. Our findings also highlight a weakness of experimental games, namely that they can be very sensitive to environmental variation and that quantitative conclusions about antisocial punishment or other behavioral strategies can easily be misleading.

  11. Implicit attitudes toward nuclear power and mobile phone base stations: support for the affect heuristic.

    Science.gov (United States)

    Siegrist, Michael; Keller, Carmen; Cousin, Marie-Eve

    2006-08-01

    The implicit association test (IAT) measures automatic associations. In the present research, the IAT was adapted to measure implicit attitudes toward technological hazards. In Study 1, implicit and explicit attitudes toward nuclear power were examined. Implicit measures (i.e., the IAT) revealed negative attitudes toward nuclear power that were not detected by explicit measures (i.e., a questionnaire). In Study 2, implicit attitudes toward EMF (electro-magnetic field) hazards were examined. Results showed that cell phone base stations and power lines are judged to be similarly risky and, further, that base stations are more closely related to risk concepts than home appliances are. No differences between experts and lay people were observed. Results of the present studies are in line with the affect heuristic proposed by Slovic and colleagues. Affect seems to be an important factor in risk perception.

  12. Mechanism Design for Base Station Association and Resource Allocation in Downlink OFDMA Network

    CERN Document Server

    Hong, Mingyi

    2012-01-01

    We consider a resource management problem in a multi-cell downlink OFDMA network, whereby the goal is to find the optimal per base station resource allocation and user-base station assignment. The users are assumed to be strategic/selfish who have private information on downlink channel states and noise levels. To induce truthfulness among the users as well as to enhance the spectrum efficiency, the resource management strategy needs to be both incentive compatible and efficient. However, due to the mixed (discrete and continuous) nature of resource management in this context, the implementation of any incentive compatible mechanism that maximizes the system throughput is NP-hard. We consider the dominant strategy implementation of an approximately optimal resource management scheme via a computationally tractable mechanism. The proposed mechanism is decentralized and dynamic. More importantly, it ensures the truthfulness of the users and it implements a resource allocation solution that yields at least 1/2 o...

  13. Combined Base Station Association and Power Control in Multi-channel Cellular Networks

    CERN Document Server

    Singh, Chandramani; Sundaresan, Rajesh

    2011-01-01

    A combined base station association and power control problem is studied for the uplink of multichannel multicell cellular networks, in which each channel is used by exactly one cell (i.e., base station). A distributed association and power update algorithm is proposed and shown to converge to a Nash equilibrium of a noncooperative game. We consider network models with discrete mobiles (yielding an atomic congestion game), as well as a continuum of mobiles (yielding a population game). We find that the equilibria need not be Pareto efficient, nor need they be system optimal. To address the lack of system optimality, we propose pricing mechanisms. It is shown that these mechanisms can be implemented in a distributed fashion.

  14. Laser based bi-directional Gbit ground links with the Tesat transportable adaptive optical ground station

    Science.gov (United States)

    Heine, Frank; Saucke, Karen; Troendle, Daniel; Motzigemba, Matthias; Bischl, Hermann; Elser, Dominique; Marquardt, Christoph; Henninger, Hennes; Meyer, Rolf; Richter, Ines; Sodnik, Zoran

    2017-02-01

    Optical ground stations can be an alternative to radio frequency based transmit (forward) and receive (return) systems for data relay services and other applications including direct to earth optical communications from low earth orbit spacecrafts, deep space receivers, space based quantum key distribution systems and Tbps capacity feeder links to geostationary spacecrafts. The Tesat Transportable Adaptive Optical Ground Station is operational since September 2015 at the European Space Agency site in Tenerife, Spain.. This paper reports about the results of the 2016 experimental campaigns including the characterization of the optical channel from Tenerife for an optimized coding scheme, the performance of the T-AOGS under different atmospheric conditions and the first successful measurements of the suitability of the Alphasat LCT optical downlink performance for future continuous variable quantum key distribution systems.

  15. A Potential Transmitter Architecture for Future Generation Green Wireless Base Station

    Directory of Open Access Journals (Sweden)

    Cijvat Ellie

    2009-01-01

    Full Text Available Abstract Current radio frequency power amplifiers in 3G base stations have very high power consumption leading to a hefty cost and negative environmental impact. In this paper, we propose a potential architecture design for future wireless base station. Issues associated with components of the architecture are investigated. The all-digital transmitter architecture uses a combination of envelope elimination and restoration (EER and pulse width modulation (PWM/pulse position modulation (PPM modulation. The performance of this architecture is predicted from the measured output power and efficiency curves of a GaN amplifier. 57% efficiency is obtained for an OFDM signal limited to 8 dB peak to average power ratio. The PWM/PPM drive signal is generated using the improved Cartesian sigma delta techniques. It is shown that an RF oversampling by a factor of four meets the WLAN spectral mask, and WCDMA specification is met by an RF oversampling of sixteen.

  16. A Potential Transmitter Architecture for Future Generation Green Wireless Base Station

    Directory of Open Access Journals (Sweden)

    Mike Faulkner

    2009-01-01

    Full Text Available Current radio frequency power amplifiers in 3G base stations have very high power consumption leading to a hefty cost and negative environmental impact. In this paper, we propose a potential architecture design for future wireless base station. Issues associated with components of the architecture are investigated. The all-digital transmitter architecture uses a combination of envelope elimination and restoration (EER and pulse width modulation (PWM/pulse position modulation (PPM modulation. The performance of this architecture is predicted from the measured output power and efficiency curves of a GaN amplifier. 57% efficiency is obtained for an OFDM signal limited to 8 dB peak to average power ratio. The PWM/PPM drive signal is generated using the improved Cartesian sigma delta techniques. It is shown that an RF oversampling by a factor of four meets the WLAN spectral mask, and WCDMA specification is met by an RF oversampling of sixteen.

  17. Cooperative Cloud Service Aware Mobile Internet Coverage Connectivity Guarantee Protocol Based on Sensor Opportunistic Coverage Mechanism

    Directory of Open Access Journals (Sweden)

    Qin Qin

    2015-01-01

    Full Text Available In order to improve the Internet coverage ratio and provide connectivity guarantee, based on sensor opportunistic coverage mechanism and cooperative cloud service, we proposed the coverage connectivity guarantee protocol for mobile Internet. In this scheme, based on the opportunistic covering rules, the network coverage algorithm of high reliability and real-time security was achieved by using the opportunity of sensor nodes and the Internet mobile node. Then, the cloud service business support platform is created based on the Internet application service management capabilities and wireless sensor network communication service capabilities, which is the architecture of the cloud support layer. The cooperative cloud service aware model was proposed. Finally, we proposed the mobile Internet coverage connectivity guarantee protocol. The results of experiments demonstrate that the proposed algorithm has excellent performance, in terms of the security of the Internet and the stability, as well as coverage connectivity ability.

  18. Survey of radiofrequency radiation levels around GSM base stations and evaluation of measurement uncertainty

    Directory of Open Access Journals (Sweden)

    Vulević Branislav D.

    2011-01-01

    Full Text Available This paper is a summary of broadband measurement values of radiofrequency radiation around GSM base stations in the vicinity of residential areas in Belgrade and 12 other cities in Serbia. It will be useful for determining non-ionizing radiation exposure levels of the general public in the future. The purpose of this paper is also an appropriate representation of basic information on the evaluation of measurement uncertainty.

  19. Structure of microprocessor-based automation system of oil pumping station “Alexndrovskaya”

    Directory of Open Access Journals (Sweden)

    Dmitriyenko Margarita A.

    2014-01-01

    Full Text Available Structure of microprocessed-based automation system (MBAS of oil pumping station (OPS «Alexandrovskaya», located on the territory of Tomsk region and forming part of the Oil Transporting Joint Stock Company «Transneft», developed in accordance with the requirements of the guidance document «Complex of the typical design choices automation of OPSs and crude storages on the basis of modern standard solutions and components».

  20. Human exposition to non ionizing electromagnetic radiations. Legislation and base stations measurements

    Directory of Open Access Journals (Sweden)

    Alonso Alonso Alonso

    2004-12-01

    Full Text Available This work deals about measurement procedures of non-ionizing radiations and their recorded levels in practice. The analyzed radiation sources cover the most common broadcasting media such as AM and FM transmissions and the GSM mobile telephony base stations. These sources currently radiate locations with high density of population. Spanish radiation level regulations are briefly described and some possible improvements are pointed out. The measurement results are discussed.

  1. Data Reduction and Control Software for Meteor Observing Stations Based on CCD Video Systems

    Science.gov (United States)

    Madiedo, J. M.; Trigo-Rodriguez, J. M.; Lyytinen, E.

    2011-01-01

    The SPanish Meteor Network (SPMN) is performing a continuous monitoring of meteor activity over Spain and neighbouring countries. The huge amount of data obtained by the 25 video observing stations that this network is currently operating made it necessary to develop new software packages to accomplish some tasks, such as data reduction and remote operation of autonomous systems based on high-sensitivity CCD video devices. The main characteristics of this software are described here.

  2. DroneCells: Improving 5G Spectral Efficiency using Drone-mounted Flying Base Stations

    OpenAIRE

    Fotouhi, Azade; Ding, Ming; Hassan, Mahbub

    2017-01-01

    We study a cellular networking scenario, called DroneCells, where miniaturized base stations (BSs) are mounted on flying drones to serve mobile users. We propose that the drones never stop, and move continuously within the cell in a way that reduces the distance between the BS and the serving users, thus potentially improving the spectral efficiency of the network. By considering the practical mobility constraints of commercial drones, we design drone mobility algorithms to improve the spectr...

  3. Developing and integrating a computer-based AM/FM radio station

    Directory of Open Access Journals (Sweden)

    Everardo Inzunza González

    2010-06-01

    Full Text Available This article presents the development of a personal computer based AM/FM radio station operating on the AM/FM commercial band. Developing the graphical user interface for the software and the interconnection with an RF function generator by means of a GPIB is presented. Computer users can enter the desired transmission frequency within the commercial band as well as the transmission potency.

  4. The effect of link-based topological changes and recoveries on the robustness of cooperation on scale-free networks

    Science.gov (United States)

    Wang, Shuai; Liu, Jing

    2016-07-01

    The emergence of cooperation is one of the key metaphors behind many social disciplines and phenomena. Existing studies show that intentional attacks on nodes damage the robustness of cooperation distinctly, and the heterogeneity among nodes promotes the emergence of cooperation. However, the impact of link-based attacks and the connectivity of networks on the cooperative mechanism is still unclear. In this paper, we focus on the effect of edge removal on the emergence of cooperation together with the connectivity of networks. The results show that malicious attacks evaluated by edge-degree are efficient to invade cooperators, and heterogeneous networks tend to perform poorly when attacks arise. Furthermore, we analyze the performance of several recovering strategies, and conclude that the connectivity is crucial to the recovery of functionality of whole networks.

  5. A reference station-based GNSS computing mode to support unified precise point positioning and real-time kinematic services

    Science.gov (United States)

    Feng, Yanming; Gu, Shengfeng; Shi, Chuang; Rizos, Chris

    2013-11-01

    Currently, the GNSS computing modes are of two classes: network-based data processing and user receiver-based processing. A GNSS reference receiver station essentially contributes raw measurement data in either the RINEX file format or as real-time data streams in the RTCM format. Very little computation is carried out by the reference station. The existing network-based processing modes, regardless of whether they are executed in real-time or post-processed modes, are centralised or sequential. This paper describes a distributed GNSS computing framework that incorporates three GNSS modes: reference station-based, user receiver-based and network-based data processing. Raw data streams from each GNSS reference receiver station are processed in a distributed manner, i.e., either at the station itself or at a hosting data server/processor, to generate station-based solutions, or reference receiver-specific parameters. These may include precise receiver clock, zenith tropospheric delay, differential code biases, ambiguity parameters, ionospheric delays, as well as line-of-sight information such as azimuth and elevation angles. Covariance information for estimated parameters may also be optionally provided. In such a mode the nearby precise point positioning (PPP) or real-time kinematic (RTK) users can directly use the corrections from all or some of the stations for real-time precise positioning via a data server. At the user receiver, PPP and RTK techniques are unified under the same observation models, and the distinction is how the user receiver software deals with corrections from the reference station solutions and the ambiguity estimation in the observation equations. Numerical tests demonstrate good convergence behaviour for differential code bias and ambiguity estimates derived individually with single reference stations. With station-based solutions from three reference stations within distances of 22-103 km the user receiver positioning results, with various

  6. Profit Allocation Scheme Among Players in Supply-Chain Based on Shapley Value of Fuzzy Bi-cooperative Games

    Institute of Scientific and Technical Information of China (English)

    YU Xiao-hui; ZHANG Qiang

    2009-01-01

    The Shapley value of fuzzy bi-cooperative game is developed based on the conventional Shapley value of bi-cooperative game.From the viewpoint that the players can participate in the coalitions to a certain extent and there are at least two independent cooperative projects for every player to choose,Shapley value which is introduced by Grabisch is extended to the case of fuzzy bi-cooperative game by Choquet integral.Moveover,the explicit fuzzy Shapley value is given.The explicit fuzzy Shapley function can be used to allocate the profits among players in supply-chain under the competitive and uncertain environment.

  7. PV-solar / wind hybrid energy system for GSM/CDMA type mobile telephony base station

    Directory of Open Access Journals (Sweden)

    Pragya Nema, R.K. Nema, Saroj Rangnekar

    2010-03-01

    Full Text Available This paper gives the design idea of optimized PV-Solar and Wind Hybrid Energy System for GSM/CDMA type mobile base station over conventional diesel generator for a particular site in central India (Bhopal . For this hybrid system ,the meteorological data of Solar Insolation, hourly wind speed, are taken for Bhopal-Central India (Longitude 77o.23'and Latitude 23o.21' and the pattern of load consumption of mobile base station are studied and suitably modeled for optimization of the hybrid energy system using HOMER software. The simulation and optimization result gives the best optimized sizing of wind turbine and solar array with diesel generator for particular GSM/CDMA type mobile telephony base station. This system is more cost effective and environmental friendly over the conventional diesel generator. It should reduced approximate 70%-80% fuel cost over conventional diesel generator and also reduced the emission of CO2 and other harmful gasses in environments. It is expected that the newly developed and installed system will provide very good opportunities for telecom sector in near future.

  8. The Mediterranean Oscillation Teleconnection Index: Station-Based versus Principal Component Paradigms

    Directory of Open Access Journals (Sweden)

    Francisco Criado-Aldeanueva

    2013-01-01

    Full Text Available Two different paradigms of the Mediterranean Oscillation (MO teleconnection index have been compared in this work: station-based definitions obtained by the difference of some climate variable between two selected points in the eastern and western basins (i.e., Algiers and Cairo, Gibraltar and Israel, Marseille and Jerusalem, or south France and Levantine basin and the principal component (PC approach in which the index is obtained as the time series of the first mode of normalised sea level pressure anomalies across the extended Mediterranean region. Interannual to interdecadal precipitation (P, evaporation (E, E-P, and net heat flux have been correlated with the different MO indices to compare their relative importance in the long-term variability of heat and freshwater budgets over the Mediterranean Sea. On an annual basis, the PC paradigm is the most effective tool to assess the effect of the large-scale atmospheric forcing in the Mediterranean Sea because the station-based indices exhibit a very poor correlation with all climatic variables and only influence a reduced fraction of the basin. In winter, the station-based indices highly improve their ability to represent the atmospheric forcing and results are fairly independent of the paradigm used.

  9. PV-solar / wind hybrid energy system for GSM/CDMA type mobile telephony base station

    Energy Technology Data Exchange (ETDEWEB)

    Nema, Pragya; Rangnekar, Saroj [Energy Engineering Department, Maulana Azad National Institute of Technology , Bhopal-462007 M.P. (India); Nema, R.K. [Electrical Engineering Department, Maulana Azad National Institute of Technology, Bhopal-462007 M.P. (India)

    2010-07-01

    This paper gives the design idea of optimized PV-Solar and Wind Hybrid Energy System for GSM/CDMA type mobile base station over conventional diesel generator for a particular site in central India (Bhopal). For this hybrid system ,the meteorological data of Solar Insolation, hourly wind speed, are taken for Bhopal-Central India (Longitude 77 deg.23'and Latitude 23 deg.21' ) and the pattern of load consumption of mobile base station are studied and suitably modeled for optimization of the hybrid energy system using HOMER software. The simulation and optimization result gives the best optimized sizing of wind turbine and solar array with diesel generator for particular GSM/CDMA type mobile telephony base station. This system is more cost effective and environmental friendly over the conventional diesel generator. It should reduced approximate 70%-80% fuel cost over conventional diesel generator and also reduced the emission of CO2 and other harmful gasses in environments. It is expected that the newly developed and installed system will provide very good opportunities for telecom sector in near future.

  10. Magnetic Base Station Deceptions, a magnetovariational analysis along the Ligurian Sea coast, Italy

    Directory of Open Access Journals (Sweden)

    E. Bozzo

    2007-06-01

    Full Text Available Reliability of high resolution airborne and shipborne magnetic surveys depends on accurate removal of temporal variations from the recorded total magnetic field intensity data. At mid latitudes, one or a few base stations are typically located within or near the survey area and are used to monitor and remove time dependent variations. These are usually assumed to be of external origin and uniform throughout the survey area. Here we investigate the influence on the magnetic base station correction of the time varying magnetic field variations generated by internal telluric currents flowing in anomalous regional 2D/3D conductivity structures. The study is based on the statistical analysis of a data set collected by four magnetovariational stations installed in northwestern Italy. The variometer stations were evenly placed with a spacing of about 60 km along a profile roughly parallel to the coastline. They recorded the geomagnetic field from the beginning to the end of April 2005, with a sampling rate of 0.33 Hz. Cross-correlation and coherence analysis applied to a subset of 125 five hours long magnetic events indicates that, for periods longer than 400 s, there is an high correlation between the horizontal magnetic field components at the different stations. This indicates spatial uniformity of the source field and of the induced currents in the 1D Earth. Additionally, the pattern of the induction arrows, estimated from single site transfer functions, reveals a clear electromagnetic signature of the Sestri-Voltaggio line, interpreted as a major regional tectonic boundary. Induced telluric currents flowing through this 2D/3D electrical conductivity discontinuity affect mainly the vertical magnetic component at the closer locations. By comparing this component at near (32 km and far (70 km stations, we have found that the mean value of the power spectra ratio, due to the electromagnetic induced field, is about 1.8 in the frequency

  11. BICM-based cooperative communication systems with relay selection: Constellation and multiplexer design

    KAUST Repository

    Malik, Muhammad Talha

    2014-09-01

    We propose a new bit-interleaved coded modulation (BICM)-based cooperative communication system where different BICM modules can be optimized jointly considering the average signal to noise ratios of the direct and the two-hop Rayleigh fading channels. As such, the full benefit of BICM can be exploited in the context of cooperative communication. Our design considers cooperative communication systems with so called max-min relay selection scheme that has no loss in performance in terms of diversity- multiplexing trade off in orthogonal cooperation. The presented numerical results for rate 1/2 convolutional code with 8-ary pulse amplitude modulation equivalently 64-ary quadrature amplitude modulation show that the proposed design can offer gains up to 1.4 dB over the traditional BICM design for a target bit error rate of 10-6. Moreover the results show that the amount of gain depends on the relays\\' positions and increases with the number of relays available for selection.

  12. Exploring Pre-Service Teachers' Historical Thinking through the Cooperative Biography: A Design-Based Research Study

    Science.gov (United States)

    Fuentes, David A.

    2012-01-01

    Through Design-Based Research (Cobb, et al., 2003), this study explores the intended outcomes and processes of the Cooperative Biography project. This research provides an "iterative analysis" (Cobb, et al., 2003) of how pre-service teachers experienced history while engaged in a Cooperative Biography, in a teacher-education setting.…

  13. NetCoDer: A Retransmission Mechanism for WSNs Based on Cooperative Relays and Network Coding

    Directory of Open Access Journals (Sweden)

    Odilson T. Valle

    2016-05-01

    Full Text Available Some of the most difficult problems to deal with when using Wireless Sensor Networks (WSNs are related to the unreliable nature of communication channels. In this context, the use of cooperative diversity techniques and the application of network coding concepts may be promising solutions to improve the communication reliability. In this paper, we propose the NetCoDer scheme to address this problem. Its design is based on merging cooperative diversity techniques and network coding concepts. We evaluate the effectiveness of the NetCoDer scheme through both an experimental setup with real WSN nodes and a simulation assessment, comparing NetCoDer performance against state-of-the-art TDMA-based (Time Division Multiple Access retransmission techniques: BlockACK, Master/Slave and Redundant TDMA. The obtained results highlight that the proposed NetCoDer scheme clearly improves the network performance when compared with other retransmission techniques.

  14. Incremental inverse kinematics based vision servo for autonomous robotic capture of non-cooperative space debris

    Science.gov (United States)

    Dong, Gangqi; Zhu, Z. H.

    2016-04-01

    This paper proposed a new incremental inverse kinematics based vision servo approach for robotic manipulators to capture a non-cooperative target autonomously. The target's pose and motion are estimated by a vision system using integrated photogrammetry and EKF algorithm. Based on the estimated pose and motion of the target, the instantaneous desired position of the end-effector is predicted by inverse kinematics and the robotic manipulator is moved incrementally from its current configuration subject to the joint speed limits. This approach effectively eliminates the multiple solutions in the inverse kinematics and increases the robustness of the control algorithm. The proposed approach is validated by a hardware-in-the-loop simulation, where the pose and motion of the non-cooperative target is estimated by a real vision system. The simulation results demonstrate the effectiveness and robustness of the proposed estimation approach for the target and the incremental control strategy for the robotic manipulator.

  15. NASA/RAE cooperation on a knowlede based flight status monitor

    Science.gov (United States)

    Butler, G. F.; Duke, E. L.

    1989-01-01

    As part of a US/UK cooperative aeronautical research pragram, a joint activity between the Dryden Flight Research Facility of the NASA Ames Research Center (Ames-Dryden) and the Royal Aerospace Establishment (RAE) on Knowledge Based Systems was established. Under the agreement, a Flight Status Monitor Knowledge base developed at Ames-Dryden was implemented using the real-time IKBS toolkit, MUSE, which was developed in the UK under RAE sponsorship. The Flight Status Monitor is designed to provide on-line aid to the flight test engineer in the interpretation of system health and status by storing expert knowledge of system behavior in an easily accessible form. The background to the cooperation is described and the details of the Flight Status Monitor, the MUSE implementation are presented.

  16. Facilitating Consensus in Cooperative Design Processes using animation-based sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter; Rosenstand, Claus Andreas Foss

    2016-01-01

    from a action research case study at the North Sea Oceanarium we show that animation can act as a tool to create clear representations of the quality criteria at hand, and thus enable a richer feedback loop between the different stakeholders in the design process. The main contribution......In the following paper we show how animation can be used as a digital sketching tool to facilitate cooperative work processes when exploring the application of non-idiomatic digital technologies. Focus is on the early stages of the design process, framed as ‘product formation’. Based on the results...... is an examination of how animation can be applied as a cooperative temporal sketching tool for establishing representations of different aspects of a design, and how it can facilitate consensus between stakeholders in the design project. We propose a set of guidelines for choosing animation-based sketching...

  17. Service allocation based on QoS evaluation in military organization cloud cooperation

    Institute of Scientific and Technical Information of China (English)

    An Zhang; Haiyang Sun; Yanxia Zhang

    2016-01-01

    The problem of cloud cooperation of military service providers (MSPs) is addressed for alocating limited resources to military service users (MSUs) that are geographicaly dis-tributed. The MSPs, also caled military organization clouds, are virtualized and encapsulated by the services they can offer and each of them contains different kinds of resources that MSU needs. The MSPs are also geographicaly dis-persed. They are required to alocate their resources to the MSU complying with the corresponding quality of service (QoS), so that each MSU gathers the services it needs to guarantee its task to be implemented. The outline of military organization cloud cooperation is discussed and the method of service optimal selection is proposed based on QoS evaluation. The QoS evaluation method based on exponential approximation is put forward to include the users’ will. Simulation results verify the effectiveness of the proposed algorithm.

  18. Object tracking with robotic total stations: Current technologies and improvements based on image data

    Science.gov (United States)

    Ehrhart, Matthias; Lienhart, Werner

    2017-09-01

    The importance of automated prism tracking is increasingly triggered by the rising automation of total station measurements in machine control, monitoring and one-person operation. In this article we summarize and explain the different techniques that are used to coarsely search a prism, to precisely aim at a prism, and to identify whether the correct prism is tracked. Along with the state-of-the-art review, we discuss and experimentally evaluate possible improvements based on the image data of an additional wide-angle camera which is available for many total stations today. In cases in which the total station's fine aiming module loses the prism, the tracked object may still be visible to the wide-angle camera because of its larger field of view. The theodolite angles towards the target can then be derived from its image coordinates which facilitates a fast reacquisition of the prism. In experimental measurements we demonstrate that our image-based approach for the coarse target search is 4 to 10-times faster than conventional approaches.

  19. Optic flow based station-keeping and wind rejection for small flying vehicles

    Science.gov (United States)

    Patrick, Bryan

    Optic flow and Wide Field Integration (WFI) have shown potential for application to autonomous navigation of Unmanned Air Vehicles (UAVs). In this study the application of these same methods to other tasks, namely station-keeping and wind rejection, is examined. Theory surrounding optic flow, WFI and wind gust modeling is examined to provide a theoretical background. A controller based on a Hinfinity bounded formulation of the well known Linear Quadratic Regulator in designed to both mitigate wind disturbances and station-keep. The performance of this controller is assessed via simulation to determine both performance and trade-offs in implementation such as the method for optic flow calculation. Furthermore, flight tests are performed to examine the real world effectiveness of the controller. Finally, conclusions about potential improvement to implementation are drawn

  20. Heat flows and energetic behavior of a telecommunication radio base station

    CERN Document Server

    Petraglia, Antonio; Vetromile, Carmela; D'Onofrio, Antonio; Lubritto, Carmine

    2015-01-01

    This paper shows a study on energetic consumption of BTSs (Base Transceiver Stations) for mobile communication, related to conditioning functions. An energetic "thermal model" of a telecommunication station is proposed and studied. The results have been validated with a BTS in central Italy, showing good agreement. Findings show a substantial high internal-external temperature difference in the containing shelter, particularly during daytime and warm months, due to sources of heat (equipment, external temperature and sun radiation) and to the difficulty in spread the warmth out. The necessity to keep the operating temperatures within a given range for the correct functioning of the electronic equipment requires the use of conditioning setups, and this significantly increases the energetic demand of the whole system. The analysis of thermal flows across the shelter can help to gather further data on its temperature behavior and to devise practical measures to lower the power demand, while keeping the operating...

  1. Performance Analysis of SNR-Based HDAF M2M Cooperative Networks

    Directory of Open Access Journals (Sweden)

    Lingwei Xu

    2015-01-01

    Full Text Available The lower bound on outage probability (OP of mobile-to-mobile (M2M cooperative networks over N-Nakagami fading channels is derived for SNR-based hybrid decode-amplify-forward (HDAF relaying. The OP performance under different conditions is evaluated through numerical simulation to verify the accuracy of the analysis. These results show that the fading coefficient, number of cascaded components, relative geometric gain, and power-allocation are important parameters that influence this performance.

  2. Markov chain-based analysis of a modified Cooper-Frieze model

    Institute of Scientific and Technical Information of China (English)

    Jin-ying TONG; Zhen-ting HOU; Ding-hua SHI

    2009-01-01

    From the perspective of probability,the stability of a modified Cooper Frieze model is studied in the present paper.Based on the concept and technique of the first-passage probability in the Markov theory,we provide a rigorous proof for the existence of the steady-state degree distribution,and derive the explicit formula analytically.Moreover,we perform extensive numerical simulations of the model,including the degree distribution and the clustering.

  3. OPTIMIZATION DESIGN OF HYDRAU-LIC MANIFOLD BLOCKS BASED ON HUMAN-COMPUTER COOPERATIVE GENETIC ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    Feng Yi; Li Li; Tian Shujun

    2003-01-01

    Optimization design of hydraulic manifold blocks (HMB) is studied as a complex solid spatial layout problem. Based on comprehensive research into structure features and design rules of HMB, an optimal mathematical model for this problem is presented. Using human-computer cooperative genetic algorithm (GA) and its hybrid optimization strategies, integrated layout and connection design schemes of HMB can be automatically optimized. An example is given to testify it.

  4. Optimal Entropy-Based Cooperative Spectrum Sensing for Maritime Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Waleed Ejaz

    2013-11-01

    Full Text Available Maritime cognitive radio networks (MCRNs have recently been proposed for opportunistic utilization of the licensed band. Spectrum sensing is one of the key issues for the successful deployment of the MCRNs. The maritime environment is unique in terms of radio wave propagation over water, surface reflection and wave occlusions. In order to deal with the challenging maritime environment, we proposed an optimal entropy-based cooperative spectrum sensing. As the results of spectrum sensing are sensitive to the number of samples in an entropy-based local detection scheme, we first calculated the optimal number of samples. Next, a cooperative spectrum sensing scheme considering the conditions of the sea environment is proposed. Finally, the throughput optimization of the m-out-of-n rule is considered. Results revealed that although the existing schemes work well for the lower sea states, they fail to perform at higher sea states. Moreover, simulation results also indicated the robustness of the entropy-based scheme and the proposed cooperative spectrum sensing scheme at higher sea states in comparison with the traditional energy detector.

  5. The Study of Cooperative Obstacle Avoidance Method for MWSN Based on Flocking Control

    Directory of Open Access Journals (Sweden)

    Zuo Chen

    2014-01-01

    Full Text Available Compared with the space fixed feature of traditional wireless sensor network (WSN, mobile WSN has better robustness and adaptability in unknown environment, so that it is always applied in the research of target tracking. In order to reach the target, the nodes group should find a self-adaptive method to avoid the obstacles together in their moving directions. Previous methods, which were based on flocking control model, realized the strategy of obstacle avoidance by means of potential field. However, these may sometimes lead the nodes group to fall into a restricted area like a trap and never get out of it. Based on traditional flocking control model, this paper introduced a new cooperative obstacle avoidance model combined with improved SA obstacle avoidance algorithm. It defined the tangent line of the intersection of node’s velocity line and the edge of obstacle as the steering direction. Furthermore, the cooperative obstacle avoidance model was also improved in avoiding complex obstacles. When nodes group encounters mobile obstacles, nodes will predict movement path based on the spatial location and velocity of obstacle. And when nodes group enters concave obstacles, nodes will temporarily ignore the gravity of the target and search path along the edge of the concave obstacles. Simulation results showed that cooperative obstacle avoidance model has significant improvement on average speed and time efficiency in avoiding obstacle compared with the traditional flocking control model. It is more suitable for obstacle avoidance in complex environment.

  6. PID Controller Parameters Tuning Based-on Satisfaction for Superheated Steam Temperature of Power Station Boiler

    Directory of Open Access Journals (Sweden)

    Benxian Xiao

    2014-06-01

    Full Text Available Proposed the PID controller parameters tuning method based-on New Luus-Jaakola (NLJ algorithm and satisfaction idea. According to the different requirements of each performance index, designed the satisfaction function with fuzzy constraint attributes, and then determined the comprehensive satisfaction function for PID tuning by NLJ algorithm. Provided the steps of PID controller parameters tuning based on the NLJ algorithm and satisfaction, and applied this tuning method to the cascade control system of superheated steam temperature for Power Station Boiler. Finally the simulation and experiment results have shown the proposed method has good dynamic and static control performances for this complicated superheated steam temperature control system.

  7. Joint Preprocesser-Based Detectors for One-Way and Two-Way Cooperative Communication Networks

    KAUST Repository

    Abuzaid, Abdulrahman I.

    2014-05-01

    Efficient receiver designs for cooperative communication networks are becoming increasingly important. In previous work, cooperative networks communicated with the use of L relays. As the receiver is constrained, channel shortening and reduced-rank techniques were employed to design the preprocessing matrix that reduces the length of the received vector from L to U. In the first part of the work, a receiver structure is proposed which combines our proposed threshold selection criteria with the joint iterative optimization (JIO) algorithm that is based on the mean square error (MSE). Our receiver assists in determining the optimal U. Furthermore, this receiver provides the freedom to choose U for each frame depending on the tolerable difference allowed for MSE. Our study and simulation results show that by choosing an appropriate threshold, it is possible to gain in terms of complexity savings while having no or minimal effect on the BER performance of the system. Furthermore, the effect of channel estimation on the performance of the cooperative system is investigated. In the second part of the work, a joint preprocessor-based detector for cooperative communication networks is proposed for one-way and two-way relaying. This joint preprocessor-based detector operates on the principles of minimizing the symbol error rate (SER) instead of minimizing MSE. For a realistic assessment, pilot symbols are used to estimate the channel. From our simulations, it can be observed that our proposed detector achieves the same SER performance as that of the maximum likelihood (ML) detector with all participating relays. Additionally, our detector outperforms selection combining (SC), channel shortening (CS) scheme and reduced-rank techniques when using the same U. Finally, our proposed scheme has the lowest computational complexity.

  8. Diagnosis of Multiple Fixture Faults in Multiple-Station Manufacturing Processes Based on State Space Approach

    Institute of Scientific and Technical Information of China (English)

    田兆青; 来新民; 林忠钦

    2004-01-01

    Dimensional quality is one of the most critical challenges in industries, which uses the multistage manufacturing process (MMP) such as assembly and machining for automotive and aerospace industries. According to investigations, fixture faults accounted for 72% of all the dimensional faults. Previous studies focused on only one fault or multiple faults occurred in one station or one fault in multiple stations, but these cases rarely appear in the real manufacturing. This paper presents a method for diagnosis of multiple fixture faults in the multi-station manufacturing process. The proposed method is based on the state space model of the MMP processes, which carries the information of the fixture layout geometry and sensor position. To identify the root cause, three continuous steps were used: a) development of the state space model and the construction of the statistics variables on offline mode, b) measurement of the coordinate measuring machines data on online mode and calculation of the statistics variables, and c) diagnostic algorithm for identifying the root cause. The presented paper integrates the state space model of the manufacturing processes and hypothesis test considering the impact of the measure noises. A case study verifies the proposed method.

  9. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks

    Directory of Open Access Journals (Sweden)

    Ming Li

    2016-09-01

    Full Text Available Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE, and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes.

  10. Reallocation of water in the state of New Mexico based on cooperative game theory

    Science.gov (United States)

    Rouhi Rad, M.

    2011-12-01

    Water allocation models often aim to maximize net benefits in the river basin based on the water rights, thus there is no motivation to use water efficiently by the users with lower marginal value for water. Water markets not only could help increase the net benefits over the basin but also will encourage the stakeholders to save the water and use it in transfer markets and increase their income. This issue can be viewed as a game in which stakeholders can play non-cooperatively and try to increase their own benefits using the amount of water assigned to them or they could cooperate and make coalitions in order to increase the total benefits in the coalition and the whole basin. The aim of this study is to reallocate the water based on cooperation among different stakeholders, namely agricultural, municipal and industrial and environmental, in the Upper Rio Grande river basin in the state of New Mexico in order to increase efficiency, sustainability and equity of water distribution in the basin using different game theory schemes such as Nucleolus and the Shapley Value.

  11. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks.

    Science.gov (United States)

    Li, Ming; Chen, Pengpeng; Gao, Shouwan

    2016-09-13

    Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE) is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE) has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE), and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes.

  12. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks

    Science.gov (United States)

    Li, Ming; Chen, Pengpeng; Gao, Shouwan

    2016-01-01

    Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE) is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE) has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE), and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes. PMID:27649170

  13. Study on DSM-based task planning of product cooperative development

    Institute of Scientific and Technical Information of China (English)

    Jiang Zengqiang; Liu Mingzhou; Zhao Han; Ge Maogen; Guo Jia

    2008-01-01

    The results of analyzing the managerial characteristics and complexity of product cooperative development suggest that task planning is an important aspect for process management of product cooperative development and the method for planning tasks should be able to model the dependency between tasks and iterations during the development process. In this paper, a DSM-based method and its corresponding optimization algorithms are developed. At first the coupled task sets and uncoupled task sets are identified, and the tasks are then optimized by the corresponding algorithms. The optimal tasks plan will reduce the development time and cost. Considering the practical requirements in real world, a Multilayer DSM is proposed, and its information communication techniques between DSM and traversing principle are described in details.

  14. Cost-Sharing of Ecological Construction Based on Trapezoidal Intuitionistic Fuzzy Cooperative Games.

    Science.gov (United States)

    Liu, Jiacai; Zhao, Wenjian

    2016-11-08

    There exist some fuzziness and uncertainty in the process of ecological construction. The aim of this paper is to develop a direct and an effective simplified method for obtaining the cost-sharing scheme when some interested parties form a cooperative coalition to improve the ecological environment of Min River together. Firstly, we propose the solution concept of the least square prenucleolus of cooperative games with coalition values expressed by trapezoidal intuitionistic fuzzy numbers. Then, based on the square of the distance in the numerical value between two trapezoidal intuitionistic fuzzy numbers, we establish a corresponding quadratic programming model to obtain the least square prenucleolus, which can effectively avoid the information distortion and uncertainty enlargement brought about by the subtraction of trapezoidal intuitionistic fuzzy numbers. Finally, we give a numerical example about the cost-sharing of ecological construction in Fujian Province in China to show the validity, applicability, and advantages of the proposed model and method.

  15. Multi-agent reinforcement learning with cooperation based on eligibility traces

    Institute of Scientific and Technical Information of China (English)

    杨玉君; 程君实; 陈佳品

    2004-01-01

    The application of reinforcement learning is widely used by multi-agent systems in recent years. An agent uses a multi-agent system to cooperate with other agents to accomplish the given task, and one agent's be-havior usually affects the others' behaviors. In traditional reinforcement learning, one agent takes the others lo-cation, so it is difficult to consider the others' behavior, which decreases the learning efficiency. This paper proposes multi-agent reinforcement learning with cooperation based on eligibility traces, i.e. one agent esti-mates the other agent's behavior with the other agent's eligibility traces. The results of this simulation prove the validity of the proposed learning method.

  16. Non-Cooperative Regulation Coordination Based on Game Theory for Wind Farm Clusters during Ramping Events

    DEFF Research Database (Denmark)

    Qi, Yongzhi; Liu, Yutian; Wu, Qiuwei

    2017-01-01

    of wind farm clusters (WFCs) in order to track scheduled wind power of the WFC during ramping events. In the proposed strategy, a non‐cooperative game is formulated and wind farms compete to provide regulation to the WFC during ramping events. A regulation revenue function is proposed to evaluate......With increasing penetration of wind power in power systems, it is important to track scheduled wind power output as much as possible during ramping events to ensure security of the system. In this paper, a non‐cooperative coordination strategy based on the game theory is proposed for the regulation...... the competition process of wind farms to provide regulation to the WFC which includes revenue of effective regulation (ER), power support regulation and punishment regulation. The multi‐time‐interval Nash equilibrium condition is derived for the regulation competition process of wind farms. By setting parameters...

  17. Space station, 1959 to . .

    Science.gov (United States)

    Butler, G. V.

    1981-04-01

    Early space station designs are considered, taking into account Herman Oberth's first space station, the London Daily Mail Study, the first major space station design developed during the moon mission, and the Manned Orbiting Laboratory Program of DOD. Attention is given to Skylab, new space station studies, the Shuttle and Spacelab, communication satellites, solar power satellites, a 30 meter diameter radiometer for geological measurements and agricultural assessments, the mining of the moons, and questions of international cooperation. It is thought to be very probable that there will be very large space stations at some time in the future. However, for the more immediate future a step-by-step development that will start with Spacelab stations of 3-4 men is envisaged.

  18. A large-scale measurement of electromagnetic fields near GSM base stations in Guangxi, China for risk communication.

    Science.gov (United States)

    Wu, Tongning; Shao, Qing; Yang, Lei; Qi, Dianyuan; Lin, Jun; Lin, Xiaojun; Yu, Zongying

    2013-06-01

    Radiofrequency (RF) electromagnetic field (EMF) exposure from wireless telecommunication base station antennae can lead to debates, conflicts or litigations among the adjacent residents if inappropriately managed. This paper presents a measurement campaign for the GSM band EMF exposure in the vicinity of 827 base station sites (totally 6207 measurement points) in Guangxi, China. Measurement specifications are designed for risk communication with the residents who previously complained of over-exposure. The EMF power densities with the global positioning system coordinate at each measured point were recorded. Compliance with the International Commission on Non-Ionizing Radiation Protection guidelines and Chinese environmental EMF safety standards was studied. The results show that the GSM band EMF level near the base stations is very low. The measurement results and the EMF risk communication procedures positively influence public perception of the RF EMF exposure from the base stations and promote the exchange of EMF exposure-related knowledge.

  19. A transition metal Lewis acid/base triad system for cooperative substrate binding.

    Science.gov (United States)

    Tutusaus, Oscar; Ni, Chengbao; Szymczak, Nathaniel K

    2013-03-06

    A frustrated Lewis pair accessory functionality is positioned in the secondary coordination sphere of a terpyridine ligand (Tpy(BN) = 6-morpholino-2,2':6',2″-terpyridine-6″-boronic acid pinacol ester) to promote directed Lewis acid/base interactions. Following metalation with VCl3, the utility of the metal Lewis acid/base triad (LABT) is highlighted with N2H4 as a cooperatively coordinated substrate, affording the first η(2)-[N2H3](-) vanadium complex.

  20. An erbium-based bifuctional heterogeneous catalyst: a cooperative route towards C-C bond formation.

    Science.gov (United States)

    Oliverio, Manuela; Costanzo, Paola; Macario, Anastasia; De Luca, Giuseppina; Nardi, Monica; Procopio, Antonio

    2014-07-15

    Heterogeneous bifuctional catalysts are multifunctional synthetic catalysts enabling efficient organic transformations by exploiting two opposite functionalities without mutual destruction. In this paper we report the first Er(III)-based metallorganic heterogeneous catalyst, synthesized by post-calcination MW-assisted grafting and modification of the natural aminoacid L-cysteine. The natural acid-base distance between sites was maintained to assure the cooperation. The applicability of this new bifunctional heterogeneous catalyst to C-C bond formation and the supposed mechanisms of action are discussed as well.

  1. An Erbium-Based Bifuctional Heterogeneous Catalyst: A Cooperative Route Towards C-C Bond Formation

    Directory of Open Access Journals (Sweden)

    Manuela Oliverio

    2014-07-01

    Full Text Available Heterogeneous bifuctional catalysts are multifunctional synthetic catalysts enabling efficient organic transformations by exploiting two opposite functionalities without mutual destruction. In this paper we report the first Er(III-based metallorganic heterogeneous catalyst, synthesized by post-calcination MW-assisted grafting and modification of the natural aminoacid L-cysteine. The natural acid–base distance between sites was maintained to assure the cooperation. The applicability of this new bifunctional heterogeneous catalyst to C-C bond formation and the supposed mechanisms of action are discussed as well.

  2. A Power Allocation Algorithm Based on Cooperative Game Theory in Multi-cell OFDM Systems

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2011-11-01

    Full Text Available A centralized resource allocation algorithm in multi-cell OFDM systems is studied, which aims at improving the performance of wireless communication systems and enhancing user’s spectral efficiency on the edge of the cell. The proposed resource allocation algorithm can be divided into two steps. The first step is sub-carrier allocation based on matrix searching in single cell and the second one is joint power allocation based on cooperative game theory in multi-cell. By comparing with traditional resource allocation algorithms in multi-cell scenario, we find that the proposed algorithm has lower computational complexity and good fairness performance.

  3. Decode-and-Forward Based Differential Modulation for Cooperative Communication System with Unitary and Non-Unitary Constellations

    CERN Document Server

    Bhatnagar, Manav R

    2012-01-01

    In this paper, we derive a maximum likelihood (ML) decoder of the differential data in a decode-and-forward (DF) based cooperative communication system utilizing uncoded transmissions. This decoder is applicable to complex-valued unitary and non-unitary constellations suitable for differential modulation. The ML decoder helps in improving the diversity of the DF based differential cooperative system using an erroneous relaying node. We also derive a piecewise linear (PL) decoder of the differential data transmitted in the DF based cooperative system. The proposed PL decoder significantly reduces the decoding complexity as compared to the proposed ML decoder without any significant degradation in the receiver performance. Existing ML and PL decoders of the differentially modulated uncoded data in the DF based cooperative communication system are only applicable to binary modulated signals like binary phase shift keying (BPSK) and binary frequency shift keying (BFSK), whereas, the proposed decoders are applicab...

  4. The Environment Friendly Power Source for Power Supply of Mobile Communication Base Stations

    Science.gov (United States)

    Rudenko, N. V.; Ershov, V. V.; Evstafiev, V. V.

    2017-05-01

    The article describes the technical proposals to improve environmental and resource characteristics of the autonomous power supply systems of mobile communication base stations based on renewable energy sources, while ensuring the required reliability and security of power supply. These include: the replacement of diesel-generator with clean energy source - an electrochemical generator based on hydrogen fuel cells; the use of wind turbines with a vertical axis; use of specialized batteries. Based on the analysis of the know technical solutions, the structural circuit diagram of the hybrid solar-wind-hydrogen power plant and the basic principles of the algorithm of its work were proposed. The implementation of these proposals will improve the environmental and resource characteristics.

  5. Mobile phone base stations and adverse health effects: phase 1 of a population-based, cross-sectional study in Germany

    DEFF Research Database (Denmark)

    Blettner, M; Schlehofer, B; Breckenkamp, J

    2009-01-01

    .7% of participants were concerned about adverse health effects of mobile phone base stations, while an additional 10.3% attributed their personal adverse health effects to the exposure from them. Participants who were concerned about or attributed adverse health effects to mobile phone base stations and those living...... in the vicinity of a mobile phone base station (500 m) reported slightly more health complaints than others. CONCLUSIONS: A substantial proportion of the German population is concerned about adverse health effects caused by exposure from mobile phone base stations. The observed slightly higher prevalence......OBJECTIVE: The aim of this first phase of a cross-sectional study from Germany was to investigate whether proximity of residence to mobile phone base stations as well as risk perception is associated with health complaints. METHODS: The researchers conducted a population-based, multi-phase, cross...

  6. A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

    Directory of Open Access Journals (Sweden)

    Chao Tan

    2015-01-01

    Full Text Available In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others.

  7. L0 Confirmation with fast, Tsa based tracking in the T-stations

    CERN Document Server

    Albrecht, J; Terrier, H

    2007-01-01

    A fast tracking algorithm to confirm the high $p_T$ L0 trigger objects with tracks from the T-stations is presented. The L0 trigger candidate is used to define a search window to a potential track. Using this, a seeded track search is performed. The track finding algorithm is based on the \\textit{TsaSeeding} algorithm~\\cite{bib:Tsa}. The efficiency to confirm a true L0 trigger signal is around 96\\%, the momentum can be measured up to $\\Delta p/p$=3\\%.

  8. DESIGN OF A SHAPED BEAM BASE STATION ANTENNA USING GENETIC ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    Liu Ying; Bu Antao; Gong Shuxi; Shen Zongzhen; Xiao Liangyong

    2003-01-01

    Genetic algorithm is used to optimize a base station antenna in order to achieve a shaped beam in a frequency band. During the optimization process, different antenna models have been evaluated using the Method of Moment (MoM). As a result of this optimization, a shaped beam antenna with suppressed sidelobe smaller than -18dB, backlobe smaller than -30dB and filled null point larger than -15dB is achieved. The proposed method is closer to reality compared with previous methods and can be used to optimize complicated antennas. The result is very useful for engineering and theoretical analysis.

  9. RIGOROUS FULL-WAVE ANALYSIS OF THE BASE-STATION ANTENNAS

    Institute of Scientific and Technical Information of China (English)

    Chen Shengbing; Zhang Fushun; Jiao Yongchang; Sun Baohua

    2002-01-01

    Rigorous analysis of the Base-Station (BS) antennas with reflector is made in this letter. The wire-grid modeling of BS antenna is established. In order to improve the solution accuracy and efficiency, some efficient techniques such as three-term sinusoidal interpolation basis function and discrete wavelet transform are used. Numerical examples considered here are the typical vertically polarized and the dual-polarized BS antennas. The calculated results for the vertically polarized BS antenna are in good agreement with the measured data, which show that the analysis modeling used is accurate and reliable.

  10. SURVEI TOPOGRAFI UNTUK MENENTUKAN GARIS TAMPAK PANDANG BASE TRANSCEIVER STATION (BTS

    Directory of Open Access Journals (Sweden)

    Arief Laila Nugraha

    2012-02-01

    Full Text Available Base Transceiver Station (BTS representation one of appliance of supporter of telecommunicationsnetwork. The development of BTS have to each other in circuit by other BTS or which have been planned.The situation BTS in circuit between other BTS without obstacle are called Line of Sight (LoS. Thetopographic survey is method of survey work to make sure the Line of Sight BTS. The topographic surveyconsist of GPS survey and study map for determination of high of BTS antenna and the Line of Sight ofBTS can be made.

  11. An EIRP Measurement Method for Base-Station Antennas Using Field Strengths Measured along a Single Straight Line

    OpenAIRE

    Soon-Soo Oh; Young-Hwan Lee

    2013-01-01

    We describe an EIRP measurement technique for a base-station antenna. The proposed method especially can be applied to the base-station antenna installed in real environments. Fresnel region measurement method is an optimal technique to avoid the far-field multipath interference, and, furthermore, it could shorten the measurement time. For detecting only the field strengths along a single straight line, we also propose a simple phase-retrieval method. For verification, a simulation and experi...

  12. Evolutionary, neurobiological, gene-based solution of the ideological "puzzle" of human altruism and cooperation.

    Science.gov (United States)

    Baschetti, Riccardo

    2007-01-01

    Despite hundreds of published articles about humankind's eusocial behaviours, most scholars still regard the origin of human altruism and cooperation as an enduring puzzle, because it seems incompatible with two central tenets of evolution, namely, the competition between individuals and the consequent selective advantages of selfish traits. This "puzzle", however, rather than being due to insurmountable scientific difficulties, is to be attributed to two powerful ideologies, which are politically opposite, but nevertheless concurred to prevent scholars from solving it. One ideology rejects the concept of genetic determinism, whereas the other dislikes the concept of group selection. As a consequence, these widespread ideologies, which are common in the scientific community, too, kept scholars from realising that the puzzle of human altruism and cooperation can only be solved by proposing a theoretical model that is based precisely on both genetic determinism and group selection. This model, which was never advanced in published papers, is presented here. This article also proposes to regard ancestral environments as determinants of human eusociality. By contrast, virtually all previous articles about it leave primitive habitats unmentioned. To support the hypothesis that human unselfish behaviours represent genetically conserved traits that evolved ancestrally, not products of cultural transmission, this paper also discusses six groups of arguments in the section "Genes versus culture". Finally, this article advances a purely genetic evolutionary explanation for the uniqueness of human eusociality, thereby challenging prevailing cultural explanations for the incomparably developed levels of cooperation in humankind, which are observed in no other social species.

  13. Cooperative Transmission for Relay Networks Based on Second-Order Statistics of Channel State Information

    Science.gov (United States)

    Li, Jiangyuan; Petropulu, Athina P.; Poor, H. Vincent

    2011-03-01

    Cooperative beamforming in relay networks is considered, in which a source transmits to its destination with the help of a set of cooperating nodes. The source first transmits locally. The cooperating nodes that receive the source signal retransmit a weighted version of it in an amplify-and-forward (AF) fashion. Assuming knowledge of the second-order statistics of the channel state information, beamforming weights are determined so that the signal-to-noise ratio (SNR) at the destination is maximized subject to two different power constraints, i.e., a total (source and relay) power constraint, and individual relay power constraints. For the former constraint, the original problem is transformed into a problem of one variable, which can be solved via Newton's method. For the latter constraint, the original problem is transformed into a homogeneous quadratically constrained quadratic programming (QCQP) problem. In this case, it is shown that when the number of relays does not exceed three the global solution can always be constructed via semidefinite programming (SDP) relaxation and the matrix rank-one decomposition technique. For the cases in which the SDP relaxation does not generate a rank one solution, two methods are proposed to solve the problem: the first one is based on the coordinate descent method, and the second one transforms the QCQP problem into an infinity norm maximization problem in which a smooth finite norm approximation can lead to the solution using the augmented Lagrangian method.

  14. Analysis of Cooperative Networks Based on WiMAX LDPC Code

    Directory of Open Access Journals (Sweden)

    M.B. Khan

    2014-11-01

    Full Text Available This study focus on the performance analysis of Cooperative communication networks based on WiMAX Low Density Parity Check (LDPC codes. The channel capacity approaching coding technique LDPC having coding gain method Bit Interleave Coded Modulation with Iterative Decoding (BICM-ID is used. The different fading environment is analyze to counter the challenges in wireless communication and provides solutions for the drawbacks in the multiple input multiple output MIMO technology. The relays are used in Cooperative communications networks to increases the range and link reliability at a lower transmit power because once the signal transmit power loses its strength it’s amplify on the relay node and when it suffers from noise it is also decoded at the relay node which increases the link reliability. LDPC with iterative decoding are used to gain BER performance only a small amount of decibel to attain Shannon limit. This performance analysis open the way for WiMAX technology can be used with Cooperative networks by using LDPC codes. The above mention communication system will provides rate, range and reliability at a lower cost, less complexity and lower transmit power.

  15. A Consensus-Based Grouping Algorithm for Multi-agent Cooperative Task Allocation with Complex Requirements.

    Science.gov (United States)

    Hunt, Simon; Meng, Qinggang; Hinde, Chris; Huang, Tingwen

    2014-01-01

    This paper looks at consensus algorithms for agent cooperation with unmanned aerial vehicles. The foundation is the consensus-based bundle algorithm, which is extended to allow multi-agent tasks requiring agents to cooperate in completing individual tasks. Inspiration is taken from the cognitive behaviours of eusocial animals for cooperation and improved assignments. Using the behaviours observed in bees and ants inspires decentralised algorithms for groups of agents to adapt to changing task demand. Further extensions are provided to improve task complexity handling by the agents with added equipment requirements and task dependencies. We address the problems of handling these challenges and improve the efficiency of the algorithm for these requirements, whilst decreasing the communication cost with a new data structure. The proposed algorithm converges to a conflict-free, feasible solution of which previous algorithms are unable to account for. Furthermore, the algorithm takes into account heterogeneous agents, deadlocking and a method to store assignments for a dynamical environment. Simulation results demonstrate reduced data usage and communication time to come to a consensus on multi-agent tasks.

  16. Modelling of cooperating robotized systems with the use of object-based approach

    Science.gov (United States)

    Foit, K.; Gwiazda, A.; Banas, W.; Sekala, A.; Hryniewicz, P.

    2015-11-01

    Today's robotized manufacturing systems are characterized by high efficiency. The emphasis is placed mainly on the simultaneous work of machines. It could manifest in many ways, where the most spectacular one is the cooperation of several robots, during work on the same detail. What's more, recently a dual-arm robots are used that could mimic the manipulative skills of human hands. As a result, it is often hard to deal with the situation, when it is necessary not only to maintain sufficient precision, but also the coordination and proper sequence of movements of individual robots’ arms. The successful completion of this task depends on the individual robot control systems and their respective programmed, but also on the well-functioning communication between robot controllers. A major problem in case of cooperating robots is the possibility of collision between particular links of robots’ kinematic chains. This is not a simple case, because the manufacturers of robotic systems do not disclose the details of the control algorithms, then it is hard to determine such situation. Another problem with cooperation of robots is how to inform the other units about start or completion of part of the task, so that other robots can take further actions. This paper focuses on communication between cooperating robotic units, assuming that every robot is represented by object-based model. This problem requires developing a form of communication protocol that the objects can use for collecting the information about its environment. The approach presented in the paper is not limited to the robots and could be used in a wider range, for example during modelling of the complete workcell or production line.

  17. Station Based Polynomial Modeling of the local ionospheric Vertical Total Electron Content (VTEC) using Particle Filter

    Science.gov (United States)

    Erdogan, Eren; Onur Karslioglu, Mahmut; Durmaz, Murat; Aghakarimi, Armin

    2014-05-01

    In this study, particle filter (PF) which is mainly based on the Monte Carlo simulation technique has been carried out for polynomial modeling of the local ionospheric conditions above the selected ground based stations. Less sensitivity to the errors caused by linearization of models and the effect of unknown or unmodeled components in the system model is one of the advantages of the particle filter as compared to the Kalman filter which is commonly used as a recursive filtering method in VTEC modeling. Besides, probability distribution of the system models is not necessarily required to be Gaussian. In this work third order polynomial function has been incorporated into the particle filter implementation to represent the local VTEC distribution. Coefficients of the polynomial model presenting the ionospheric parameters and the receiver inter frequency biases are the unknowns forming the state vector which has been estimated epoch-wise for each ground station. To consider the time varying characteristics of the regional VTEC distribution, dynamics of the state vector parameters changing permanently have been modeled using the first order Gauss-Markov process. In the processing of the particle filtering, multi-variety probability distribution of the state vector through the time has been approximated by means of randomly selected samples and their associated weights. A known drawback of the particle filtering is that the increasing number of the state vector parameters results in an inefficient filter performance and requires more samples to represent the probability distribution of the state vector. Considering the total number of unknown parameters for all ground stations, estimation of these parameters which were inserted into a single state vector has caused the particle filter to produce inefficient results. To solve this problem, the PF implementation has been carried out separately for each ground station at current time epochs. After estimation of unknown

  18. Assessment of Radio-Frequency Radiation Exposure Level from Selected Mobile Base Stations (MBS) in Lokoja, Kogi State, Nigeria

    CERN Document Server

    Victor, U J Nwankwo; Dada, S S; Onugba, A A; Ushie, P

    2012-01-01

    The acquisition and use of mobile phone is tremendously increasing especially in developing countries, but not without a concern. The greater concern among the public is principally over the proximity of mobile base stations (MBS) to residential areas rather than the use of handsets. In this paper, we present an assessment of Radio-Frequency (RF) radiation exposure level measurements and analysis of radiation power density (in \\mu W/sq m) from mobile base stations relative to radial distance (in metre). The minimum average power density from individual base station in the town was about 47\\mu W/sq m while the average maximum was about 1.5mW/sq m. Our result showed that average power density of a base station decreases with increase in distance (from base station) and that radiation intensity varies from one base station to another even at the same distance away. Our result (obtained signature of power density variation) was also compared with the 'expected' signature. It was found that radiation from external...

  19. Analysis of local ionospheric variability based on SVD and MDS at low-latitude GNSS stations

    Science.gov (United States)

    Dabbakuti, J. R. K. Kumar; Devanaboyina, Venkata Ratnam; Kanchumarthi, S. Ramesh

    2016-06-01

    Investigation of ionospheric anomalies during equatorial and low latitude is of major concern for modeling and global navigation satellite system (GNSS) applications. Total electron content (TEC) varies with the ionospheric conditions, which will lead to the errors in the global positioning system (GPS) measurements. It is therefore a method that is necessary to characterize the ionospheric anomalies for satellite-based navigation systems. In this study, characterization of ionospheric variations based on the singular value decomposition (SVD) and classical multidimensional scaling (MDS) methods was studied. The yearly and daily variations are decomposed from the GPS-TEC, international reference ionosphere (IRI) 2007 and IRI 2012 models TEC over the three low-latitude GNSS stations located at Koneru Lakshmaiah University (KLU-Guntur), Hyderabad and Bangalore, respectively. From the results, it is found that there is a strong correlation between GPS-TEC and IRI models. The correlation coefficient for the first three singular values is more than 0.86. From this, it is possible to reconstruct more than 85 % of the variability contained in global GPS-derived VTEC data (for year 2013) by using only the first three modes. The semiannual variation has maximum value during March-April and September-October and has minimum value during June-July. It is observed that the annual variations have maximum value in summer and minimum value in winter, and the amplitudes decrease with increasing latitude. Further, opposite latitudinal asymmetry among annual and semiannual variations for three GNSS stations is noticed. SVD and MDS methods clearly show time-varying characteristics and the absence of the winter anomaly at low-latitude GNSS stations.

  20. International Space Station as a Base Camp for Exploration Beyond Low Earth Orbit

    Science.gov (United States)

    Raftery, Michael; Hoffman, Jeffrey

    2011-01-01

    The idea for using the International Space Station (ISS) as platform for exploration has matured in the past year and the concept continues to gain momentum. ISS provides a robust infrastructure which can be used to test systems and capabilities needed for missions to the Moon, Mars, asteroids and other potential destinations. International cooperation is a critical enabler and ISS has already demonstrated successful management of a large multi-national technical endeavor. Systems and resources needed for expeditions can be aggregated and thoroughly tested at ISS before departure thus providing wide operational flexibility and the best assurance of mission success. A small part of ISS called an Exploration Platform (ISS-EP) can be placed at Earth-Moon Libration point 1 (EML1) providing immediate benefits and flexibility for future exploration missions. We will show how ISS and the ISS-EP can be used to reduce risk and improve the operational flexibility for missions beyond low earth orbit. Life support systems and other technology developed for ISS can be evolved and adapted to the ISS-EP and other exploration spacecraft. New technology, such as electric propulsion and advanced life support systems can be tested and proven at ISS as part of an incremental development program. Commercial companies who are introducing transportation and other services will benefit with opportunities to contribute to the mission since ISS will serve as a focal point for the commercialization of low earth orbit services. Finally, we will show how use of ISS provides immediate benefits to the scientific community because its capabilities are available today and certain critical aspects of exploration missions can be simulated.

  1. Assessing Measurement Distances for OTA Testing of Massive MIMO Base Station at 28 GHz

    DEFF Research Database (Denmark)

    Kyösti, Pekka; Fan, Wei; Kyrolainen, Jukka

    2017-01-01

    This paper discusses physical dimensions for a multi probe anechoic chamber based (MPAC) over-the-air (OTA) setup aiming for base station (BS) testing. The target frequency of the simulated massive multiple-input-multiple-output (MIMO) BS arrays is 28 GHz. The assessment is performed with two...... metrics. The first metric is a new power metric based on assumptions of a code book of fixed beams and planar waves. The second one is the multi-user (MU) MIMO sum rate capacity. The intention is to evaluate physical dimensions in metres with respect to different BS array sizes. Simulation results...... indicate that OTA performance of a BS array with maximum dimension of 0.15m could be measured with a setup having measurement distance of approximately 1m...

  2. Distributed Linear Precoder Optimization and Base Station Selection for an Uplink Heterogeneous Network

    CERN Document Server

    Hong, Mingyi

    2012-01-01

    In a heterogeneous wireless cellular network, each user may be covered by multiple access points such as macro/pico/relay/femto base stations (BS). An effective approach to maximize the sum utility (e.g., system throughput) in such a network is to jointly optimize users' linear procoders as well as their base station associations. In this paper we first show that this joint optimization problem is NP-hard and thus is difficult to solve to global optimality. To find a locally optimal solution, we formulate the problem as a noncooperative game in which the users and the BSs both act as players. We introduce a set of new utility functions for the players and show that every Nash equilibrium (NE) of the resulting game is a stationary solution of the original sum utility maximization problem. Moreover, we develop a best-response type algorithm that allows the players to distributedly reach a NE of the game. Simulation results show that the proposed distributed algorithm can effectively relieve local BS congestion ...

  3. Energy-Aware Base Stations: The Effect of Planning, Management, and Femto Layers

    Directory of Open Access Journals (Sweden)

    G. Koutitas

    2014-01-01

    Full Text Available We compare the performance of three base station management schemes on three different network topologies. In addition, we explore the effect of offloading traffic to heterogeneous femtocell layer upon energy savings taking into account the increase of base station switch-off time intervals. Fairness between mobile operator and femtocell owners is maintained since current femtocell technologies present flat power consumption curves with respect to served traffic. We model two different user-to-femtocell association rules in order to capture realistic and maximum gains from the heterogeneous network. To provide accurate findings and a holistic overview of the techniques, we explore a real urban district where channel estimations and power control are modeled using deterministic algorithms. Finally, we explore energy efficiency metrics that capture savings in the mobile network operator, the required watts per user and watts per bitrate. It is found that the newly established pseudo distributed management scheme is the most preferable solution for practical implementations and together with the femotcell layer the network can handle dynamic load control that is regarded as the basic element of future demand response programs.

  4. Efficiency Evaluation of Vegetable Specialized Cooperatives Based on Data of Chongqing Municipality

    Institute of Scientific and Technical Information of China (English)

    Zimin; LIU; Dan; YANG

    2014-01-01

    By introducing development situation of specialized cooperatives and vegetable specialized cooperatives in China,this paper discussed existing problems in the process of development of China’s vegetable specialized cooperatives. Then,it made efficiency evaluation on typical vegetable specialized cooperatives in 3 districts of Chongqing Municipality by the DEA method. Considering traditional DEA model has drawbacks,it introduced super efficiency DEA model to make complete identification and ordering of cooperatives. On this basis,it divided efficiency value into pure technical efficiency and scale efficiency,and classified cooperatives into 4 categories according to efficiency characteristics of non-complete effective cooperatives. Finally,it came up with recommendations and countermeasures for improving efficiency of specialized cooperatives from raising technical level and increasing members of specialized cooperatives.

  5. Performance of static positioning for medium distances based on data from a virtual reference station and ASG-PL Network

    Science.gov (United States)

    Bakula, M.

    The use of a network of reference stations instead of a single reference station allows the modelling of some systematic errors in a region and allows a user to increase the distance between the rover receiver and reference stations. In some countries, GPS reference stations exist and GPS observations are available for users in real-time mode and in post-processing. Observations from several GPS reference stations in a regional network enable modelling spatially-correlated errors and their modelling on an epoch-by-epoch and satellite-by-satellite basis. As a result, observations of a virtual reference station can be created at a rover's approximate position and its observations can be used in the precise baseline positioning of the rover. This paper presents the performance of the static positioning of a rover station, its quality and reliability for two different baselines. Single-baseline and network static solutions are presented and compared. Network solutions are based on data from a virtual reference station (VRS) obtained by the Wasoft/Virtuall software. In both cases, the same strategy of ambiguity resolution was used. These approaches have been tested with the use of 24-hour GPS data from the Polish Active Geodetic Network (ASG-PL). The data from three reference stations with medium-range separation were used in the process of generating VRS data. GPS data of the rover station were divided into 20, 10 and 5-min. sessions with a sampling interval of 5 sec. Practical calculations and analyses of horizontal and vertical accuracy of coordinates clearly show the improvement of static positioning in terms of time observation span and ambiguity reliability.

  6. Comparison of technology-based cooperative learning with technology-based individual learning in enhancing fundamental nursing proficiency.

    Science.gov (United States)

    Lin, Zu-Chun

    2013-05-01

    The aim of nursing education is to prepare students with critical thinking, high interests in profession and high proficiency in patient care. Cooperative learning promotes team work and encourages knowledge building upon discussion. It has been viewed as one of the most powerful learning methods. Technology has been considered an influential tool in teaching and learning. It assists students in gathering more information to solve the problems and master skills better. The purpose of this study was to compare the effect of technology-based cooperative learning with technology-based individual learning in nursing students' critical thinking in catheterization knowledge gaining, error discovering, skill acquisitions, and overall scores. This study used a pretest-posttest experimental design. Ninety-eight students were assigned randomly to one of two groups. Questionnaires and tests were collected at baseline and after completion of intervention. The results of this study showed that there was no significant difference in related catheterization skill performance. However, the remaining variables differed greatly between the two groups. CONCLUSIONS AND APPLICATIONS: This study's findings guide the researchers and instructors to use technology-based cooperative learning more appropriately. Future research should address the design of the course module and the availability of mobile devices to reach student-centered and learn on the move goals. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Limit span of self-anchored cable-stayed suspension cooperation system bridge based on strength

    Institute of Scientific and Technical Information of China (English)

    Zhe ZHANG; Huili WANG; Sifeng QIN; Xiaomeng GE

    2009-01-01

    The limit span of self-anchored cable-stayed suspension bridge is deduced. The relations among the geometrical parameters, loads and material characteristics are also analyzed. Based on the material strength and commonly used materials, the limit spans of self-anchored cable-stayed suspension bridges with concrete girder or steel girder under vertical static load are discussed in detail.The corresponding upper limit spans and the effect of the factors on the span are given. The results indicate that increasing rise-span ratio, height-span ratio and cable-stayed segment length or reducing the second dead load could increase the cooperation system span.

  8. Fuzzy variable impedance control based on stiffness identification for human-robot cooperation

    Science.gov (United States)

    Mao, Dachao; Yang, Wenlong; Du, Zhijiang

    2017-06-01

    This paper presents a dynamic fuzzy variable impedance control algorithm for human-robot cooperation. In order to estimate the intention of human for co-manipulation, a fuzzy inference system is set up to adjust the impedance parameter. Aiming at regulating the output fuzzy universe based on the human arm’s stiffness, an online stiffness identification method is developed. A drag interaction task is conducted on a 5-DOF robot with variable impedance control. Experimental results demonstrate that the proposed algorithm is superior.

  9. A LINEAR PRECODING STRATEGY BASED ON PARTICLE SWARM OPTIMIZATION IN MULTICELL COOPERATIVE TRANSMISSION

    Institute of Scientific and Technical Information of China (English)

    Zhang Rui; Song Rongfang

    2011-01-01

    An optimal linear precoding scheme based on Particle Swarm Optimization (PSO),which aims to maximize the system capacity of the cooperative transmission in the downlink channel,is proposed for a multicell multiuser single input single output system.With such a scheme,the optimal precoding vector could be easily searched for each user according to a simplified objective function.Simulation results show that the proposed scheme can obtain larger average spectrum efficiency and a better Bit Error Rate (BER) performance than Zero Forcing (ZF) and Minimum Mean Square Error (MMSE) algorithm.

  10. Latitudinal GRBR-TEC estimation in Southeast Asia region based on the two-station method

    Science.gov (United States)

    Watthanasangmechai, Kornyanat; Yamamoto, Mamoru; Saito, Akinori; Tsugawa, Takuya; Yokoyama, Tatsuhiro; Supnithi, Pornchai; Yatini, Clara Yono

    2014-10-01

    Total electron content (TEC) is an important parameter for revealing latitudinal ionospheric structures, such as the equatorial ionization anomaly (EIA) in Southeast Asia. Understanding the EIA is beneficial for studying equatorial spread F. To reveal the structures, the absolute TEC as a function of latitude must be accurately determined. In early 2012, we expanded a GNU Radio Beacon Receiver (GRBR) network to provide latitudinal coverage in the Thailand-Indonesia sector. We employed the GRBR network to receive VHF and UHF signals from polar low-Earth-orbit satellites. The TEC offset is an unknown parameter in the absolute TEC estimation process. We propose a new technique based on the two-station method to estimate the offset for the latitudinal TEC estimation, and it works better than the original method for a sparse network. The TEC estimation system requires two iterations to minimize the root-mean-square error (RMSE). Once the RMSE reaches the global minimum, the absolute TECs are estimated simultaneously over five GRBR stations. GPS-TECs from local stations are used as the initial guess of the offset estimation. The height of the ionospheric pierce point is determined from the ionosonde hmF2. As a result, the latitudinal GRBR-TEC was successfully estimated from the polar orbit satellites. The two EIA humps were clearly captured by the GRBR-TEC. The result was well verified with the TEC reconstructed from the C/NOFS density data and the ionosonde bottomside data. This is a significant step showing that the GRBR is a useful tool for the study of low-latitude ionospheric features.

  11. Robust and Cooperative Image-Based Visual Servoing System Using a Redundant Architecture

    Directory of Open Access Journals (Sweden)

    Francisco J. Badesa

    2011-12-01

    Full Text Available The reliability and robustness of image-based visual servoing systems is still unsolved by the moment. In order to address this issue, a redundant and cooperative 2D visual servoing system based on the information provided by two cameras in eye-in-hand/eye-to-hand configurations is proposed. Its control law has been defined to assure that the whole system is stable if each subsystem is stable and to allow avoiding typical problems of image-based visual servoing systems like task singularities, features extraction errors, disappearance of image features, local minima, etc. Experimental results with an industrial robot manipulator based on Schunk modular motors to demonstrate the stability, performance and robustness of the proposed system are presented.

  12. The study of single station inverting the sea surface current by HF ground wave radar based on adjoint assimilation technology

    Science.gov (United States)

    Han, Shuzong; Yang, Hua; Xue, Wenhu; Wang, Xingchi

    2017-06-01

    This paper introduces the assimilation technology in an ocean dynamics model and discusses the feasibility of inverting the sea surface current in the detection zone by assimilating the sea current radial velocity detected by single station HF ground wave radar in ocean dynamics model. Based on the adjoint assimilation and POM model, the paper successfully inverts the sea surface current through single station HF ground wave radar in the Zhoushan sea area. The single station HF radar inversion results are also compared with the bistatic HF radar composite results and the fixed point measured results by Annderaa current meter. The error analysis shows that acquisition of flow velocity and flow direction data from the single station HF radar based on adjoint assimilation and POM model is viable and the data obtained have a high correlation and consistency with the flow field observed by HF radar.

  13. Relay selection based on MAP estimation for cooperative communication with outdated channel state information

    Institute of Scientific and Technical Information of China (English)

    Ding Wenrui; Fei Li; Gao Qiang; Liu Shuo

    2013-01-01

    In this paper,we consider an amplify-and-forward (AF) cooperative communication system when the channel state information (CSI) used in relay selection differs from that during data transmission,i.e.,the CSI used in relay selection is outdated.The selected relay may not be actually the best for data transmission and the outage performance of the cooperative system will deteriorate.To improve its performance,we propose a relay selection strategy based on maximum a posteriori (MAP) estimation,where relay is selected based on predicted signal-to-noise ratio (SNR).To reduce the computation complexity,we approximate the a posteriori probability density of SNR and obtain a closed-form predicted SNR,and a relay selection strategy based on the approximate MAP estimation (RS-AMAP) is proposed.The simulation results show that this approximation leads to trivial performance loss from the perspective of outage probability.Compared with relay selection strategies given in the literature,the outage probability is reduced largely through RS-AMAP for medium-to-large transmitting powers and medium-to-high channel correlation coefficients.

  14. Distributed Fault Detection Based on Credibility and Cooperation for WSNs in Smart Grids.

    Science.gov (United States)

    Shao, Sujie; Guo, Shaoyong; Qiu, Xuesong

    2017-04-28

    Due to the increasingly important role in monitoring and data collection that sensors play, accurate and timely fault detection is a key issue for wireless sensor networks (WSNs) in smart grids. This paper presents a novel distributed fault detection mechanism for WSNs based on credibility and cooperation. Firstly, a reasonable credibility model of a sensor is established to identify any suspicious status of the sensor according to its own temporal data correlation. Based on the credibility model, the suspicious sensor is then chosen to launch fault diagnosis requests. Secondly, the sending time of fault diagnosis request is discussed to avoid the transmission overhead brought about by unnecessary diagnosis requests and improve the efficiency of fault detection based on neighbor cooperation. The diagnosis reply of a neighbor sensor is analyzed according to its own status. Finally, to further improve the accuracy of fault detection, the diagnosis results of neighbors are divided into several classifications to judge the fault status of the sensors which launch the fault diagnosis requests. Simulation results show that this novel mechanism can achieve high fault detection ratio with a small number of fault diagnoses and low data congestion probability.

  15. Efficient and Secure Information Sharing For Security Personnels: A Role and Cooperation Based Approach

    Directory of Open Access Journals (Sweden)

    G.K. Pradhan

    2010-07-01

    Full Text Available To facilitate users to interact with and share information without difficulty and faultlessly across various networks and databases nationwide, a secure and trusted information-sharing environment has been recognized as an imperative requirement and to advance homeland security effort. The key incentive following this research is to build a secure and trusted information-sharing approach for governmentdepartments. This paper presents an efficient role and cooperation based information sharing approach for secure exchange of confidential and top secret information amongst security personnels and government departments within the national boundaries using public key cryptography. The devised approach makes use of cryptographic hash function; public key cryptosystem and a unique and complex mapping function for securely exchanging confidential information. Furthermore, the proposed approach facilitates privacy preserving information sharing with probable restrictions based on the rank of the security personnels. The developed role and cooperation based information sharing approach ensures secure and stream-lined information sharing among security personnels and government intelligence departments to avoid threatening activities. The experimental results demonstrate the effectiveness of theproposed information sharing approach.

  16. A soft-hard combination-based cooperative spectrum sensing scheme for cognitive radio networks.

    Science.gov (United States)

    Do, Nhu Tri; An, Beongku

    2015-02-13

    In this paper we propose a soft-hard combination scheme, called SHC scheme, for cooperative spectrum sensing in cognitive radio networks. The SHC scheme deploys a cluster based network in which Likelihood Ratio Test (LRT)-based soft combination is applied at each cluster, and weighted decision fusion rule-based hard combination is utilized at the fusion center. The novelties of the SHC scheme are as follows: the structure of the SHC scheme reduces the complexity of cooperative detection which is an inherent limitation of soft combination schemes. By using the LRT, we can detect primary signals in a low signal-to-noise ratio regime (around an average of -15 dB). In addition, the computational complexity of the LRT is reduced since we derive the closed-form expression of the probability density function of LRT value. The SHC scheme also takes into account the different effects of large scale fading on different users in the wide area network. The simulation results show that the SHC scheme not only provides the better sensing performance compared to the conventional hard combination schemes, but also reduces sensing overhead in terms of reporting time compared to the conventional soft combination scheme using the LRT.

  17. Role of the right inferior frontal gyrus in turn-based cooperation and competition: A near-infrared spectroscopy study.

    Science.gov (United States)

    Liu, Tao; Saito, Hirofumi; Oi, Misato

    2015-10-01

    Interpersonal interaction can be classified into two types: concurrent and turn-based interaction, requiring synchronized body-movement and complementary behaviors across persons, respectively. To examine the neural mechanism of turn-based interaction, we simultaneously measured paired participants activations in their bilateral inferior frontal gyrus (IFG) and the bilateral inferior parietal lobule (IPL) in a turn-taking game using near-infrared spectroscopy (NIRS). Pairs of participants were assigned to either one of two roles (game builder and the partner) in the game. The builder's task was to make a copy of a target disk-pattern by placing disks on a monitor, while the partner's task was to aid the builder in his/her goal (cooperation condition) or to obstruct it (competition condition). The builder always took the initial move and the partner followed. The NIRS data demonstrated an interaction of role (builder vs. partner) by task-type (cooperation vs. competition) in the right IFG. The builder in the cooperation condition showed higher activation than the cooperator, but the same builder in the competition condition showed lower activation than in the cooperation condition. The activations in the competitor-builder pairs showed positive correlation between their right IFG, but the activations in the cooperator-builder pairs did not. These results suggest that the builder's activation in the right IFG is reduced/increased in the context of interacting with a cooperative/competitive partner. Also, the competitor may actively trace the builder's disk manipulation, leading to deeper mind-set synchronization in the competition condition, while the cooperator may passively follow the builder's move, leading to shallower mind-set synchronization in the cooperation condition.

  18. Joint Base Station Clustering and Beamformer Design for Partial Coordinated Transmission in Heterogenous Networks

    CERN Document Server

    Hong, Mingyi; Baligh, Hadi; Luo, Zhi-Quan

    2012-01-01

    We consider the interference management problem in a multicell MIMO heterogenous network. Within each cell there are a large number of distributed micro/pico base stations (BSs) that can be potentially coordinated for joint transmission. To reduce coordination overhead, we consider user-centric BS clustering so that each user is served by only a small number of (potentially overlapping) BSs. Thus, given the channel state information, our objective is to jointly design the BS clustering and the linear beamformers for all BSs in the network. In this paper, we formulate this problem from a {sparse optimization} perspective, and propose an efficient algorithm that is based on iteratively solving a sequence of group LASSO problems. A novel feature of the proposed algorithm is that it performs BS clustering and beamformer design jointly rather than separately as is done in the existing approaches for partial coordinated transmission. Moreover, the cluster size can be controlled by adjusting a single penalty paramet...

  19. Exploiting Phase Diversity for CDMA2000 1X Smart Antenna Base Stations

    Directory of Open Access Journals (Sweden)

    Hyeon Seungheon

    2004-01-01

    Full Text Available A performance analysis of an access channel decoder is presented which exploits a diversity gain due to the independent magnitude of received signals energy at each of the antenna elements of a smart-antenna base-station transceiver subsystem (BTS operating in CDMA2000 1X signal environment. The objective is to enhance the data retrieval at cellsite during the access period, for which the optimal weight vector of the smart antenna BTS is not available. It is shown in this paper that the access channel decoder proposed in this paper outperforms the conventional one, which is based on a single antenna channel in terms of detection probability of access probe, access channel failure probability, and Walsh-code demodulation performance.

  20. Downlink Video Streaming for Users Non-Equidistant from Base Station

    Directory of Open Access Journals (Sweden)

    S. Pejoski

    2012-06-01

    Full Text Available We consider multiuser video transmission for users that are non-equidistantly positioned from base station. We propose a greedy algorithm for video streaming in a wireless system with capacity achieving channel coding, that implements the cross-layer principle by partially separating the physical and the application layer. In such a system the parameters at the physical layer are dependent on the packet length and the conditions in the wireless channel and the parameters at the application layer are dependent on the reduction of the expected distortion assuming no packet errors in the system. We also address the fairness in the multiuser video system with non-equidistantly positioned users. Our fairness algorithm is based on modified opportunistic round robin scheduling. We evaluate the performance of the proposed algorithms by simulating the transmission of H.264/AVC video signals in a TDMA wireless system.

  1. International Space Station-Based Electromagnetic Launcher for Space Science Payloads

    Science.gov (United States)

    Jones, Ross M.

    2013-01-01

    A method was developed of lowering the cost of planetary exploration missions by using an electromagnetic propulsion/launcher, rather than a chemical-fueled rocket for propulsion. An electromagnetic launcher (EML) based at the International Space Station (ISS) would be used to launch small science payloads to the Moon and near Earth asteroids (NEAs) for the science and exploration missions. An ISS-based electromagnetic launcher could also inject science payloads into orbits around the Earth and perhaps to Mars. The EML would replace rocket technology for certain missions. The EML is a high-energy system that uses electricity rather than propellant to accelerate payloads to high velocities. The most common type of EML is the rail gun. Other types are possible, e.g., a coil gun, also known as a Gauss gun or mass driver. The EML could also "drop" science payloads into the Earth's upper

  2. A Redox-Controllable Molecular Switch Based on Weak Recognition of BPX26C6 at a Diphenylurea Station

    Directory of Open Access Journals (Sweden)

    Jia-Cheng Chang

    2015-01-01

    Full Text Available The Na+ ion–assisted recognition of urea derivatives by BPX26C6 has allowed the construction of a redox-controllable [2]rotaxane-type molecular switch based on two originally very weakly interacting host/guest systems. Using NOBF4 to oxidize the triarylamine terminus into a corresponding radical cation attracted the macrocyclic component toward its adjacent carbamate station; subsequent addition of Zn powder moved the macrocyclic component back to its urea station.

  3. Fire Stations - 2007

    Data.gov (United States)

    Kansas Data Access and Support Center — Fire Station Locations in Kansas Any location where fire fighters are stationed at or based out of, or where equipment that such personnel use in carrying out their...

  4. Fire Stations - 2009

    Data.gov (United States)

    Kansas Data Access and Support Center — Fire Stations in Kansas Any location where fire fighters are stationed or based out of, or where equipment that such personnel use in carrying out their jobs is...

  5. Design and Development of a CPCI-Based Electronics Package for Space Station Experiments

    Science.gov (United States)

    Kolacz, John S.; Clapper, Randy S.; Wade, Raymond P.

    2006-01-01

    The NASA John H. Glenn Research Center is developing a Compact-PCI (CPCI) based electronics package for controlling space experiment hardware on the International Space Station. Goals of this effort include an easily modified, modular design that allows for changes in experiment requirements. Unique aspects of the experiment package include a flexible circuit used for internal interconnections and a separate enclosure (box in a box) for controlling 1 kW of power for experiment fuel heating requirements. This electronics package was developed as part of the FEANICS (Flow Enclosure Accommodating Novel Investigations in Combustion of Solids) mini-facility which is part of the Fluids and Combustion Facility s Combustion Integrated Rack (CIR). The CIR will be the platform for future microgravity combustion experiments and will reside on the Destiny Module of the International Space Station (ISS). The FEANICS mini-facility will be the primary means for conducting solid fuel combustion experiments in the CIR on ISS. The main focus of many of these solid combustion experiments will be to conduct applied scientific investigations in fire-safety to support NASA s future space missions. A description of the electronics package and the results of functional testing are the subjects of this report. The report concludes that the use of innovative packaging methods combined with readily available COTS hardware can provide a modular electronics package which is easily modified for changing experiment requirements.

  6. Passenger Flow Prediction of Subway Transfer Stations Based on Nonparametric Regression Model

    Directory of Open Access Journals (Sweden)

    Yujuan Sun

    2014-01-01

    Full Text Available Passenger flow is increasing dramatically with accomplishment of subway network system in big cities of China. As convergence nodes of subway lines, transfer stations need to assume more passengers due to amount transfer demand among different lines. Then, transfer facilities have to face great pressure such as pedestrian congestion or other abnormal situations. In order to avoid pedestrian congestion or warn the management before it occurs, it is very necessary to predict the transfer passenger flow to forecast pedestrian congestions. Thus, based on nonparametric regression theory, a transfer passenger flow prediction model was proposed. In order to test and illustrate the prediction model, data of transfer passenger flow for one month in XIDAN transfer station were used to calibrate and validate the model. By comparing with Kalman filter model and support vector machine regression model, the results show that the nonparametric regression model has the advantages of high accuracy and strong transplant ability and could predict transfer passenger flow accurately for different intervals.

  7. Wind Energy Based Electric Vehicle Charging Stations Sitting. A GIS/Wind Resource Assessment Approach

    Directory of Open Access Journals (Sweden)

    George Xydis

    2015-11-01

    Full Text Available The transportation sector is severely correlated with major problems in environment, citizens’ health, climate and economy. Issues such as traffic, fuel cost and parking space have make life more difficult, especially in the dense urban environment. Thus, there is a great need for the development of the electric vehicle (EV sector. The number of cars in cities has increased so much that the current transportation system (roads, parking places, traffic lights, etc. cannot accommodate them properly. The increasing number of vehicles does not affect only humans but also the environment, through air and noise pollution. According to EPA, the 39.2% of total gas emissions in 2007 was caused by transportation activities. Studies have shown that the pollutants are not only gathered in the major roads and/or highways but can travel depending on the meteorological conditions leading to generic pollution. The promotion of EVs and the charging stations are both equally required to be further developed in order EVs to move out of the cities and finally confront the range problem. In this work, a wind resource and a GIS analysis optimizes in a wider area the sitting of wind based charging stations and proposes an optimizing methodology.

  8. Simple random sampling-based probe station selection for fault detection in wireless sensor networks.

    Science.gov (United States)

    Huang, Rimao; Qiu, Xuesong; Rui, Lanlan

    2011-01-01

    Fault detection for wireless sensor networks (WSNs) has been studied intensively in recent years. Most existing works statically choose the manager nodes as probe stations and probe the network at a fixed frequency. This straightforward solution leads however to several deficiencies. Firstly, by only assigning the fault detection task to the manager node the whole network is out of balance, and this quickly overloads the already heavily burdened manager node, which in turn ultimately shortens the lifetime of the whole network. Secondly, probing with a fixed frequency often generates too much useless network traffic, which results in a waste of the limited network energy. Thirdly, the traditional algorithm for choosing a probing node is too complicated to be used in energy-critical wireless sensor networks. In this paper, we study the distribution characters of the fault nodes in wireless sensor networks, validate the Pareto principle that a small number of clusters contain most of the faults. We then present a Simple Random Sampling-based algorithm to dynamic choose sensor nodes as probe stations. A dynamic adjusting rule for probing frequency is also proposed to reduce the number of useless probing packets. The simulation experiments demonstrate that the algorithm and adjusting rule we present can effectively prolong the lifetime of a wireless sensor network without decreasing the fault detected rate.

  9. Graph theoretic framework based cooperative control and estimation of multiple UAVs for target tracking

    Science.gov (United States)

    Ahmed, Mousumi

    Designing the control technique for nonlinear dynamic systems is a significant challenge. Approaches to designing a nonlinear controller are studied and an extensive study on backstepping based technique is performed in this research with the purpose of tracking a moving target autonomously. Our main motivation is to explore the controller for cooperative and coordinating unmanned vehicles in a target tracking application. To start with, a general theoretical framework for target tracking is studied and a controller in three dimensional environment for a single UAV is designed. This research is primarily focused on finding a generalized method which can be applied to track almost any reference trajectory. The backstepping technique is employed to derive the controller for a simplified UAV kinematic model. This controller can compute three autopilot modes i.e. velocity, ground heading (or course angle), and flight path angle for tracking the unmanned vehicle. Numerical implementation is performed in MATLAB with the assumption of having perfect and full state information of the target to investigate the accuracy of the proposed controller. This controller is then frozen for the multi-vehicle problem. Distributed or decentralized cooperative control is discussed in the context of multi-agent systems. A consensus based cooperative control is studied; such consensus based control problem can be viewed from the algebraic graph theory concepts. The communication structure between the UAVs is represented by the dynamic graph where UAVs are represented by the nodes and the communication links are represented by the edges. The previously designed controller is augmented to account for the group to obtain consensus based on their communication. A theoretical development of the controller for the cooperative group of UAVs is presented and the simulation results for different communication topologies are shown. This research also investigates the cases where the communication

  10. Neuro-Fuzzy Prediction of Cooperation Interaction Profile of Flexible Road Train Based on Hybrid Automaton Modeling

    Directory of Open Access Journals (Sweden)

    Banjanovic-Mehmedovic Lejla

    2016-01-01

    Full Text Available Accurate prediction of traffic information is important in many applications in relation to Intelligent Transport systems (ITS, since it reduces the uncertainty of future traffic states and improves traffic mobility. There is a lot of research done in the field of traffic information predictions such as speed, flow and travel time. The most important research was done in the domain of cooperative intelligent transport system (C-ITS. The goal of this paper is to introduce the novel cooperation behaviour profile prediction through the example of flexible Road Trains useful road cooperation parameter, which contributes to the improvement of traffic mobility in Intelligent Transportation Systems. This paper presents an approach towards the control and cooperation behaviour modelling of vehicles in the flexible Road Train based on hybrid automaton and neuro-fuzzy (ANFIS prediction of cooperation profile of the flexible Road Train. Hybrid automaton takes into account complex dynamics of each vehicle as well as discrete cooperation approach. The ANFIS is a particular class of the ANN family with attractive estimation and learning potentials. In order to provide statistical analysis, RMSE (root mean square error, coefficient of determination (R2 and Pearson coefficient (r, were utilized. The study results suggest that ANFIS would be an efficient soft computing methodology, which could offer precise predictions of cooperative interactions between vehicles in Road Train, which is useful for prediction mobility in Intelligent Transport systems.

  11. 47 CFR 0.434 - Data bases and lists of authorized broadcast stations and pending broadcast applications.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Data bases and lists of authorized broadcast... Commission § 0.434 Data bases and lists of authorized broadcast stations and pending broadcast applications. Periodically the FCC makes available copies of its data bases and lists containing information about...

  12. A monocular vision system based on cooperative targets detection for aircraft pose measurement

    Science.gov (United States)

    Wang, Zhenyu; Wang, Yanyun; Cheng, Wei; Chen, Tao; Zhou, Hui

    2017-08-01

    In this paper, a monocular vision measurement system based on cooperative targets detection is proposed, which can capture the three-dimensional information of objects by recognizing the checkerboard target and calculating of the feature points. The aircraft pose measurement is an important problem for aircraft’s monitoring and control. Monocular vision system has a good performance in the range of meter. This paper proposes an algorithm based on coplanar rectangular feature to determine the unique solution of distance and angle. A continuous frame detection method is presented to solve the problem of corners’ transition caused by symmetry of the targets. Besides, a displacement table test system based on three-dimensional precision and measurement system human-computer interaction software has been built. Experiment result shows that it has a precision of 2mm in the range of 300mm to 1000mm, which can meet the requirement of the position measurement in the aircraft cabin.

  13. MAS-Based Cooperative Control for Biotechnological Process-A Case Study

    Science.gov (United States)

    Choinski, Dariusz; Metzger, Mieczyslaw; Nocon, Witold

    The MAS-based control seems to be better suited for manufacturing control because of its discrete event character. Nevertheless, for continuous industrial processes the MAS-based control can be also very attractive. In this paper, a synthesis of the MAS-based control system for the continuous process is presented. A biological reactor is controlled using respirometric approach. In this approach, both standard control loops and additional experiments are performed to obtain measurements not available on-line. Therefore, the system consists of different control agents being able to cooperate or to inhibit each other in order to achieve the appropriate goals. A case study experiments are realized using an experimental wastewater treatment pilot plant.

  14. Research on Marketing Cooperation System Based on Multi-Agent Services Aggregation Driven by Requirement

    Directory of Open Access Journals (Sweden)

    Hong ZHOU

    2010-11-01

    Full Text Available The web service has great significance and value since it represents a large industrial sector and huge trade interests, but the function of a single web service is too small to satisfy the need of service requestor, so it is necessary to combine a mount of simple services to satisfy the complex and dynamic requirement in practice, then the problem of web services composition is one of the research hotspot. This paper generalized the primary interaction processes between enterprise and customer in marketing, encapsulated the special function for marketing works as the agent, and considered the marketing as the cooperation process of agents focusing on requirements, and based on that a multi-agent based marketing cooperation system (MAMCS is established and the agent ontology is designed according to JADE, finally the negotiation mechanism is built. The method of multi-agent services aggregation driven by requirement supposed in this paper can improve the utilizing effect of service, reduce the difficulty of services composition, and realize the automatic purpose of services composition. Moreover, by combining the merits of agent technique the initiation and intelligence of the services are improved, that safeguard the best interests of the service providers due to they have an option on requirements.

  15. Robust Feature Selection from Microarray Data Based on Cooperative Game Theory and Qualitative Mutual Information.

    Science.gov (United States)

    Mortazavi, Atiyeh; Moattar, Mohammad Hossein

    2016-01-01

    High dimensionality of microarray data sets may lead to low efficiency and overfitting. In this paper, a multiphase cooperative game theoretic feature selection approach is proposed for microarray data classification. In the first phase, due to high dimension of microarray data sets, the features are reduced using one of the two filter-based feature selection methods, namely, mutual information and Fisher ratio. In the second phase, Shapley index is used to evaluate the power of each feature. The main innovation of the proposed approach is to employ Qualitative Mutual Information (QMI) for this purpose. The idea of Qualitative Mutual Information causes the selected features to have more stability and this stability helps to deal with the problem of data imbalance and scarcity. In the third phase, a forward selection scheme is applied which uses a scoring function to weight each feature. The performance of the proposed method is compared with other popular feature selection algorithms such as Fisher ratio, minimum redundancy maximum relevance, and previous works on cooperative game based feature selection. The average classification accuracy on eleven microarray data sets shows that the proposed method improves both average accuracy and average stability compared to other approaches.

  16. Adaptive Cooperative FEC Based on Combination of Network Coding and Channel Coding for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yong Jin

    2014-02-01

    Full Text Available The data delivery over wireless links with QoS-guarantee is a big challenge because of the unreliable and dynamic characteristics of wireless sensor networks, as well as QoS diversity requirements of applications. In this paper, we propose an adaptive cooperative Forward Error Correction algorithm based on network coding, in the hope quality of experience could be satisfied on receivers with high quality. The algorithm, based on wireless link and distance, adjusts the RS coder parameter and selects the optimal relay nodes. On the other hand, we combine the channel coding and network coding technology at the data link layer to fulfil the requirements of QoS diversity. Both mathematical analysis and NS simulation results demonstrate the proposed mechanism is superior to the traditional FEC and cooperative FEC alone at the reliability, real time performance and energy efficiency. In addition, the proposed mechanism can significantly improve quality of media streaming, in terms of playable frame rate on the receiving side. 

  17. Autonomous robotic capture of non-cooperative target by adaptive extended Kalman filter based visual servo

    Science.gov (United States)

    Dong, Gangqi; Zhu, Zheng H.

    2016-05-01

    This paper presents a real-time, vision-based algorithm for the pose and motion estimation of non-cooperative targets and its application in visual servo robotic manipulator to perform autonomous capture. A hybrid approach of adaptive extended Kalman filter and photogrammetry is developed for the real-time pose and motion estimation of non-cooperative targets. Based on the pose and motion estimates, the desired pose and trajectory of end-effector is defined and the corresponding desired joint angles of the robotic manipulator are derived by inverse kinematics. A close-loop visual servo control scheme is then developed for the robotic manipulator to track, approach and capture the target. Validating experiments are designed and performed on a custom-built six degrees of freedom robotic manipulator with an eye-in-hand configuration. The experimental results demonstrate the feasibility, effectiveness and robustness of the proposed adaptive extended Kalman filter enabled pose and motion estimation and visual servo strategy.

  18. An Accurate Non-Cooperative Method for Measuring Textureless Spherical Target Based on Calibrated Lasers

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2016-12-01

    Full Text Available Strong demands for accurate non-cooperative target measurement have been arising recently for the tasks of assembling and capturing. Spherical objects are one of the most common targets in these applications. However, the performance of the traditional vision-based reconstruction method was limited for practical use when handling poorly-textured targets. In this paper, we propose a novel multi-sensor fusion system for measuring and reconstructing textureless non-cooperative spherical targets. Our system consists of four simple lasers and a visual camera. This paper presents a complete framework of estimating the geometric parameters of textureless spherical targets: (1 an approach to calibrate the extrinsic parameters between a camera and simple lasers; and (2 a method to reconstruct the 3D position of the laser spots on the target surface and achieve the refined results via an optimized scheme. The experiment results show that our proposed calibration method can obtain a fine calibration result, which is comparable to the state-of-the-art LRF-based methods, and our calibrated system can estimate the geometric parameters with high accuracy in real time.

  19. Individual wealth-based selection supports cooperation in spatial public goods games.

    Science.gov (United States)

    Chen, Xiaojie; Szolnoki, Attila

    2016-09-06

    In a social dilemma game group members are allowed to decide if they contribute to the joint venture or not. As a consequence, defectors, who do not invest but only enjoy the mutual benefit, prevail and the system evolves onto the tragedy of the common state. This unfortunate scenario can be avoided if participation is not obligatory but only happens with a given probability. But what if we also consider a player's individual wealth when to decide about participation? To address this issue we propose a model in which the probabilistic participation in the public goods game is combined with a conditional investment mode that is based on individual wealth: if a player's wealth exceeds a threshold value then it is qualified and can participate in the joint venture. Otherwise, the participation is forbidden in the investment interactions. We show that if only probabilistic participation is considered, spatially structured populations cannot support cooperation better than well-mixed populations where full defection state can also be avoided for small participation probabilities. By adding the wealth-based criterion of participation, however, structured populations are capable to augment network reciprocity relevantly and allow cooperator strategy to dominate in a broader parameter interval.

  20. Robust Feature Selection from Microarray Data Based on Cooperative Game Theory and Qualitative Mutual Information

    Directory of Open Access Journals (Sweden)

    Atiyeh Mortazavi

    2016-01-01

    Full Text Available High dimensionality of microarray data sets may lead to low efficiency and overfitting. In this paper, a multiphase cooperative game theoretic feature selection approach is proposed for microarray data classification. In the first phase, due to high dimension of microarray data sets, the features are reduced using one of the two filter-based feature selection methods, namely, mutual information and Fisher ratio. In the second phase, Shapley index is used to evaluate the power of each feature. The main innovation of the proposed approach is to employ Qualitative Mutual Information (QMI for this purpose. The idea of Qualitative Mutual Information causes the selected features to have more stability and this stability helps to deal with the problem of data imbalance and scarcity. In the third phase, a forward selection scheme is applied which uses a scoring function to weight each feature. The performance of the proposed method is compared with other popular feature selection algorithms such as Fisher ratio, minimum redundancy maximum relevance, and previous works on cooperative game based feature selection. The average classification accuracy on eleven microarray data sets shows that the proposed method improves both average accuracy and average stability compared to other approaches.

  1. Individual wealth-based selection supports cooperation in spatial public goods games

    Science.gov (United States)

    Chen, Xiaojie; Szolnoki, Attila

    2016-09-01

    In a social dilemma game group members are allowed to decide if they contribute to the joint venture or not. As a consequence, defectors, who do not invest but only enjoy the mutual benefit, prevail and the system evolves onto the tragedy of the common state. This unfortunate scenario can be avoided if participation is not obligatory but only happens with a given probability. But what if we also consider a player’s individual wealth when to decide about participation? To address this issue we propose a model in which the probabilistic participation in the public goods game is combined with a conditional investment mode that is based on individual wealth: if a player’s wealth exceeds a threshold value then it is qualified and can participate in the joint venture. Otherwise, the participation is forbidden in the investment interactions. We show that if only probabilistic participation is considered, spatially structured populations cannot support cooperation better than well-mixed populations where full defection state can also be avoided for small participation probabilities. By adding the wealth-based criterion of participation, however, structured populations are capable to augment network reciprocity relevantly and allow cooperator strategy to dominate in a broader parameter interval.

  2. Base Station Ordering for Emergency Call Localization in Ultra-dense Cellular Networks

    KAUST Repository

    Elsawy, Hesham

    2017-10-04

    This paper proposes the base station ordering localization technique (BoLT) for emergency call localization in cellular networks. Exploiting the foreseen ultra-densification of the next-generation (5G and beyond) cellular networks, we utilize higher-order Voronoi tessellations to provide ubiquitous localization services that are in compliance to the public safety standards in cellular networks. The proposed localization algorithm runs at the base stations (BSs) and requires minimal operation from agents (i.e., mobile users). Particularly, BoLT requires each agent to feedback a neighbor cell list (NCL) that contains the order of neighboring BSs based on the received signal power in the pilots sent from these BSs. Moreover, this paper utilizes stochastic geometry to develop a tractable mathematical model to assess the performance of BoLT in a general network setting. The goal of this paper is to answer the following two fundamental questions: i) how many BSs should be ordered and reported by the agent to achieve a desirable localization accuracy? and ii) what is the localization error probability given that the pilot signals are subject to shadowing? Assuming that the BSs are deployed according to a Poisson point process (PPP), we answer these two questions via characterizing the tradeoff between the area of location region (ALR) and the localization error probability in terms of the number of BSs ordered by the agent. The results show that reporting the order of six neighboring BSs is sufficient to localize the agent within 10% of the cell area. Increasing the number of reported BSs to ten confines the location region to 1% of the cell area. This would translate to the range of a few meters to decimeters in the foreseen ultra-dense 5G networks.

  3. Estimation of selected streamflow statistics for a network of low-flow partial-record stations in areas affected by Base Realignment and Closure (BRAC) in Maryland

    Science.gov (United States)

    Ries, Kernell G.; Eng, Ken

    2010-01-01

    The U.S. Geological Survey, in cooperation with the Maryland Department of the Environment, operated a network of 20 low-flow partial-record stations during 2008 in a region that extends from southwest of Baltimore to the northeastern corner of Maryland to obtain estimates of selected streamflow statistics at the station locations. The study area is expected to face a substantial influx of new residents and businesses as a result of military and civilian personnel transfers associated with the Federal Base Realignment and Closure Act of 2005. The estimated streamflow statistics, which include monthly 85-percent duration flows, the 10-year recurrence-interval minimum base flow, and the 7-day, 10-year low flow, are needed to provide a better understanding of the availability of water resources in the area to be affected by base-realignment activities. Streamflow measurements collected for this study at the low-flow partial-record stations and measurements collected previously for 8 of the 20 stations were related to concurrent daily flows at nearby index streamgages to estimate the streamflow statistics. Three methods were used to estimate the streamflow statistics and two methods were used to select the index streamgages. Of the three methods used to estimate the streamflow statistics, two of them--the Moments and MOVE1 methods--rely on correlating the streamflow measurements at the low-flow partial-record stations with concurrent streamflows at nearby, hydrologically similar index streamgages to determine the estimates. These methods, recommended for use by the U.S. Geological Survey, generally require about 10 streamflow measurements at the low-flow partial-record station. The third method transfers the streamflow statistics from the index streamgage to the partial-record station based on the average of the ratios of the measured streamflows at the partial-record station to the concurrent streamflows at the index streamgage. This method can be used with as few as

  4. Integrating stations from the North America Gravity Database into a local GPS-based land gravity survey

    Science.gov (United States)

    Shoberg, Thomas G.; Stoddard, Paul R.

    2013-01-01

    The ability to augment local gravity surveys with additional gravity stations from easily accessible national databases can greatly increase the areal coverage and spatial resolution of a survey. It is, however, necessary to integrate such data seamlessly with the local survey. One challenge to overcome in integrating data from national databases is that these data are typically of unknown quality. This study presents a procedure for the evaluation and seamless integration of gravity data of unknown quality from a national database with data from a local Global Positioning System (GPS)-based survey. The starting components include the latitude, longitude, elevation and observed gravity at each station location. Interpolated surfaces of the complete Bouguer anomaly are used as a means of quality control and comparison. The result is an integrated dataset of varying quality with many stations having GPS accuracy and other reliable stations of unknown origin, yielding a wider coverage and greater spatial resolution than either survey alone.

  5. A Compact MultiBand and Dual-Polarized Mobile Base-Station Antenna Using Optimal Array Structure

    Directory of Open Access Journals (Sweden)

    Young-Bae Jung

    2015-01-01

    Full Text Available This paper introduces a multiband base-station antenna to provide multiple communications services. There is growing need for multiband base-station antennas for mobile communications to serve existing 2nd and 3rd generation systems and to provide emerging 4th generation communication service as well as WiFi. For example, cellular, PCS, and especially WCDMA service are currently widely used in Korea, and 4th generation service (WiBro and LTE, introduced in 2011, will have to operate in parallel with existing services. The proposed multiband base-station antenna can provide a single/dual/triple or more multiple services using dual-polarization (±45° linear polarizations according to the requirements of the service provider. This antenna has a shared aperture, having several array antenna sets for multiple services (Band 1: cellular service in 0.824~0.894 GHz, Band 2: PCS, WCDMA, and WiFi in 1.920~2.170 GHz, Band 3: WiBro and WiMAX in 2.300~2.400 GHz, and Band 4: WiMAX in 5.150~5.850 GHz. This antenna can be helpful for reducing base-station operating expenses and to create a clean urban landscape by minimizing the number of base-station antennas, which are increasing rapidly.

  6. Low-cost extrapolation method for maximal LTE radio base station exposure estimation: test and validation.

    Science.gov (United States)

    Verloock, Leen; Joseph, Wout; Gati, Azeddine; Varsier, Nadège; Flach, Björn; Wiart, Joe; Martens, Luc

    2013-06-01

    An experimental validation of a low-cost method for extrapolation and estimation of the maximal electromagnetic-field exposure from long-term evolution (LTE) radio base station installations are presented. No knowledge on downlink band occupation or service characteristics is required for the low-cost method. The method is applicable in situ. It only requires a basic spectrum analyser with appropriate field probes without the need of expensive dedicated LTE decoders. The method is validated both in laboratory and in situ, for a single-input single-output antenna LTE system and a 2×2 multiple-input multiple-output system, with low deviations in comparison with signals measured using dedicated LTE decoders.

  7. National surveys of radiofrequency field strengths from radio base stations in Africa.

    Science.gov (United States)

    Joyner, Ken H; Van Wyk, Marthinus J; Rowley, Jack T

    2014-01-01

    The authors analysed almost 260 000 measurement points from surveys of radiofrequency (RF) field strengths near radio base stations in seven African countries over two time frames from 2001 to 2003 and 2006 to 2012. The results of the national surveys were compared, chronological trends investigated and potential exposures compared by technology and with frequency modulation (FM) radio. The key findings from thes data are that irrespective of country, the year and mobile technology, RF fields at a ground level were only a small fraction of the international human RF exposure recommendations. Importantly, there has been no significant increase in typical measured levels since the introduction of 3G services. The mean levels in these African countries are similar to the reported levels for countries of Asia, Europe and North America using similar mobile technologies. The median level for the FM services in South Africa was comparable to the individual but generally lower than the combined mobile services.

  8. Evaluation of RF electromagnetic field exposure levels from cellular base stations in Korea.

    Science.gov (United States)

    Kim, Byung Chan; Park, Seong-Ook

    2010-09-01

    This article presents the measurement results of human exposure to CDMA800 and CDMA1800 signals at locations in Korea where the general public has expressed concern. Measurements were performed at 50 locations across the country to compare the electromagnetic field levels with the general public exposure compliance limits. At each site, the distances between the nearest single or co-located base station and measurement positions were within a range of approximately 32-422 m. The measured exposure levels were very low compared with the international standard and the Korean human protection notice. The highest field level was 1.5 V/m, which corresponds to 0.15% of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines for human exposure. 2010 Wiley-Liss, Inc.

  9. On Dimensions of OTA Setups for Massive MIMO Base Stations Radiated Testing

    DEFF Research Database (Denmark)

    Kyösti, Pekka; Fan, Wei; Pedersen, Gert F.

    2016-01-01

    The development of base stations (BS) with large aperture antenna arrays, enabled partially by the utilization of cmWave and mmWave frequency bands, will require radiated testing in fading conditions. In this paper, the objective is to investigate the suitable measurement distances and physical...... (DoA) estimation algorithm as well as multi-user MIMO sum-rate capacity are investigated to determine the range of the test setup. It was found that the link budget doesn’t support for the measurement distances claimed by the Fraunhofer distance. Most of the utilized metrics, especially the sum rate...... capacity, indicate that smaller setup sizes can still yield reasonable measurement accuracy. Simulations were performed at 2.6, 3.5, and 28 GHz frequencies....

  10. Energy-Efficient Network Transmission between Satellite Swarms and Earth Stations Based on Lyapunov Optimization Techniques

    Directory of Open Access Journals (Sweden)

    Weiwei Fang

    2014-01-01

    Full Text Available The recent advent of satellite swarm technologies has enabled space exploration with a massive number of picoclass, low-power, and low-weight spacecraft. However, developing swarm-based satellite systems, from conceptualization to validation, is a complex multidisciplinary activity. One of the primary challenges is how to achieve energy-efficient data transmission between the satellite swarm and terrestrial terminal stations. Employing Lyapunov optimization techniques, we present an online control algorithm to optimally dispatch traffic load among different satellite-ground links for minimizing overall energy consumption over time. Our algorithm is able to independently and simultaneously make control decisions on traffic dispatching over intersatellite-links and up-down-links so as to offer provable energy and delay guarantees, without requiring any statistical information of traffic arrivals and link condition. Rigorous analysis and extensive simulations have demonstrated the performance and robustness of the proposed new algorithm.

  11. A Seed-Based Plant Propagation Algorithm: The Feeding Station Model

    Directory of Open Access Journals (Sweden)

    Muhammad Sulaiman

    2015-01-01

    Full Text Available The seasonal production of fruit and seeds is akin to opening a feeding station, such as a restaurant. Agents coming to feed on the fruit are like customers attending the restaurant; they arrive at a certain rate and get served at a certain rate following some appropriate processes. The same applies to birds and animals visiting and feeding on ripe fruit produced by plants such as the strawberry plant. This phenomenon underpins the seed dispersion of the plants. Modelling it as a queuing process results in a seed-based search/optimisation algorithm. This variant of the Plant Propagation Algorithm is described, analysed, tested on nontrivial problems, and compared with well established algorithms. The results are included.

  12. Mesospheric CO above Troll station, Antarctica observed by a ground based microwave radiometer

    Directory of Open Access Journals (Sweden)

    C. Straub

    2013-01-01

    Full Text Available This paper presents mesospheric carbon monoxide (CO data acquired by the ground-based microwave radiometer of the British Antarctic Survey (BAS radiometer stationed at Troll station in Antarctica (72° S, 2.5° E, 1270 a.m.s.l.. The data set covers the period from February 2008 to January 2010, however, due to very low CO concentrations below approximately 80 km altitude in summer, profiles can only be retrieved during Antarctic winter. CO is measured for approximately 2 h each day and profiles are retrieved approximately every half hour. The retrieved profiles, covering the pressure range from 1 to 0.01 hPa (approximately 48 to 80 km, are compared to measurements from Aura/MLS and SD-WACCM. This intercomparison reveals a low bias of 0.5 to 1 ppmv at 0.1 hPa (approximately 64 km and 2.5 to 3.5 ppmv at 0.01 hPa (approximately 80 km of the BAS microwave radiometer compared to both reference datasets. One explanation for this low bias could be the known high bias of MLS which is in the same order of magnitude. The ground based radiometer shows high and significant correlation (coefficients higher than 0.9/0.65 compared to MLS/SD-WACCM at all altitudes compared with both reference datasets. doi:10.5285/DE3E2092-406D-47A9-9205-3971A8DFB4A9

  13. Mesospheric CO above Troll station, Antarctica observed by a ground based microwave radiometer

    Directory of Open Access Journals (Sweden)

    C. Straub

    2013-06-01

    Full Text Available This paper presents mesospheric carbon monoxide (CO data acquired by the ground-based microwave radiometer of the British Antarctic Survey (BAS radiometer stationed at Troll station in Antarctica (72° S, 2.5° E, 1270 m a.s.l.. The dataset covers the period from February 2008 to January 2010, however, due to very low CO concentrations below approximately 80 km altitude in summer, profiles are only presented during the Antarctic winter. CO is measured for approximately 2 h each day and profiles are retrieved approximately every half hour. The retrieved profiles, covering the pressure range from 1 to 0.01 hPa (approximately 48 to 80 km, are compared to measurements from Microwave Limb Sounder on the Aura satellite (Aura/MLS and Whole Atmosphere Community Climate Model with Specified Dynamics (SD-WACCM. This intercomparison reveals a low bias of 0.5 to 1 ppmv at 0.1 hPa (approximately 64 km and 2.5 to 3.5 ppmv at 0.01 hPa (approximately 80 km of the BAS microwave radiometer compared to both reference datasets. One explanation for this low bias could be the known high bias of MLS which is on the same order of magnitude. The ground based radiometer shows high and significant correlation (coefficients higher than 0.9/0.7 compared to MLS/SD-WACCM at all altitudes compared with both reference datasets. The dataset can be accessed under http://dx.doi.org/10/mhq.

  14. Risk and benefit perceptions of mobile phone and base station technology in Bangladesh.

    Science.gov (United States)

    van Kleef, Ellen; Fischer, Arnout R H; Khan, Moin; Frewer, Lynn J

    2010-06-01

    Research in developed countries showed that many citizens perceive that radio signals transmitted by mobile phones and base stations represent potential health risks. Less research has been conducted in developing countries focused on citizen perceptions of risks and benefits, despite the recent and rapid introduction of mobile communication technologies. This study aims to identify factors that are influential in determining the tradeoffs that Bangladeshi citizens make between risks and benefits in terms of mobile phone technology acceptance and health concerns associated with the technology. Bangladesh was selected as representative of many developing countries inasmuch as terrestrial telephone infrastructure is insubstantial, and mobile phone use has expanded rapidly over the last decade, even among the poor. Issues of importance were identified in a small-scale qualitative study among Bangladeshi citizens (n = 13), followed by a survey within a sample of Bangladeshi citizens (n = 500). The results demonstrate that, in general, the perceived benefits of mobile phone technology outweigh the risks. The perceived benefits are primarily related to the social and personal advantages of mobile phone use, including the ability to receive emergency news about floods, cyclones, and other natural disasters. Base stations were seen as a symbol of societal advance. The results furthermore suggest that overall risk perceptions are relatively low, in particular health risks, and are primarily driven by perceptions that related to crime and social inconvenience. Perceived health risks are relatively small. These findings show that risk communication and management may be particularly effective when contextual factors of the society where the system is implemented are taken into consideration.

  15. A Lightweight Neighbor-Info-Based Routing Protocol for No-Base-Station Taxi-Call System

    Science.gov (United States)

    Zhu, Xudong; Wang, Jinhang; Chen, Yunchao

    2014-01-01

    Since the quick topology change and short connection duration, the VANET has had unstable routing and wireless signal quality. This paper proposes a kind of lightweight routing protocol-LNIB for call system without base station, which is applicable to the urban taxis. LNIB maintains and predicts neighbor information dynamically, thus finding the reliable path between the source and the target. This paper describes the protocol in detail and evaluates the performance of this protocol by simulating under different nodes density and speed. The result of evaluation shows that the performance of LNIB is better than AODV which is a classic protocol in taxi-call scene. PMID:24737984

  16. A lightweight neighbor-info-based routing protocol for no-base-station taxi-call system.

    Science.gov (United States)

    Zhu, Xudong; Wang, Jinhang; Chen, Yunchao

    2014-01-01

    Since the quick topology change and short connection duration, the VANET has had unstable routing and wireless signal quality. This paper proposes a kind of lightweight routing protocol-LNIB for call system without base station, which is applicable to the urban taxis. LNIB maintains and predicts neighbor information dynamically, thus finding the reliable path between the source and the target. This paper describes the protocol in detail and evaluates the performance of this protocol by simulating under different nodes density and speed. The result of evaluation shows that the performance of LNIB is better than AODV which is a classic protocol in taxi-call scene.

  17. Joint preprocesser-based detector for cooperative networks with limited hardware processing capability

    KAUST Repository

    Abuzaid, Abdulrahman I.

    2015-02-01

    In this letter, a joint detector for cooperative communication networks is proposed when the destination has limited hardware processing capability. The transmitter sends its symbols with the help of L relays. As the destination has limited hardware, only U out of L signals are processed and the energy of the remaining relays is lost. To solve this problem, a joint preprocessing based detector is proposed. This joint preprocessor based detector operate on the principles of minimizing the symbol error rate (SER). For a realistic assessment, pilot symbol aided channel estimation is incorporated for this proposed detector. From our simulations, it can be observed that our proposed detector achieves the same SER performance as that of the maximum likelihood (ML) detector with all participating relays. Additionally, our detector outperforms selection combining (SC), channel shortening (CS) scheme and reduced-rank techniques when using the same U. Our proposed scheme has low computational complexity.

  18. A Cooperative Spectrum Sensing Scheme Based on Trust and Fuzzy Logic for Cognitive Radio Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yonghua Wang

    2013-01-01

    Full Text Available This paper proposes a cooperative spectrum sensing scheme based on trust and fuzzy logic for Cognitive Radio Sensor Networks (CRSN. The CRSN nodes use the T-S fuzzy logic to make local decisions on the presence or absence of the primary users (PU signal, and then use a censoring method to only allow the relatively reliable decisions sent to the fusion center. Utilizing a trust evaluation scheme based on the factors such as local sensing difference, sensing location factors, and sensing channel conditions for each node. Combing the majority rule and the trust values of the nodes, the fusion center makes the final decision. Simulation results show that the proposed scheme could improve the detect probability effectively.

  19. A Comparison of Parametric and Sample-Based Message Representation in Cooperative Localization

    Directory of Open Access Journals (Sweden)

    Jaime Lien

    2012-01-01

    Full Text Available Location awareness is a key enabling feature and fundamental challenge in present and future wireless networks. Most existing localization methods rely on existing infrastructure and thus lack the flexibility and robustness necessary for large ad hoc networks. In this paper, we build upon SPAWN (sum-product algorithm over a wireless network, which determines node locations through iterative message passing, but does so at a high computational cost. We compare different message representations for SPAWN in terms of performance and complexity and investigate several types of cooperation based on censoring. Our results, based on experimental data with ultra-wideband (UWB nodes, indicate that parametric message representation combined with simple censoring can give excellent performance at relatively low complexity.

  20. Cooperative Learning through Team-Based Projects in the Biotechnology Industry.

    Science.gov (United States)

    Luginbuhl, Sarah C; Hamilton, Paul T

    2013-01-01

    We have developed a cooperative-learning, case studies project model that has teams of students working with biotechnology professionals on company-specific problems. These semester-long, team-based projects can be used effectively to provide students with valuable skills in an industry environment and experience addressing real issues faced by biotechnology companies. Using peer-evaluations, we have seen improvement in students' professional skills such as time-management, quality of work, and level of contribution over multiple semesters. This model of team-based, industry-sponsored projects could be implemented in other college and university courses/programs to promote professional skills and expose students to an industry setting.

  1. Cooperative Learning through Team-Based Projects in the Biotechnology Industry

    Directory of Open Access Journals (Sweden)

    Sarah C. Luginbuhl

    2013-08-01

    Full Text Available We have developed a cooperative-learning, case studies project model that has teams of students working with biotechnology professionals on company-specific problems. These semester-long, team-based projects can be used effectively to provide students with valuable skills in an industry environment and experience addressing real issues faced by biotechnology companies. Using peer-evaluations, we have seen improvement in students’ professional skills such as time-management, quality of work, and level of contribution over multiple semesters. This model of team-based, industry-sponsored projects could be implemented in other college and university courses/programs to promote professional skills and expose students to an industry setting.

  2. Optimal Facility Location Model Based on Genetic Simulated Annealing Algorithm for Siting Urban Refueling Stations

    Directory of Open Access Journals (Sweden)

    Dawei Chen

    2015-01-01

    Full Text Available This paper analyzes the impact factors and principles of siting urban refueling stations and proposes a three-stage method. The main objective of the method is to minimize refueling vehicles’ detour time. The first stage aims at identifying the most frequently traveled road segments for siting refueling stations. The second stage focuses on adding additional refueling stations to serve vehicles whose demands are not directly satisfied by the refueling stations identified in the first stage. The last stage further adjusts and optimizes the refueling station plan generated by the first two stages. A genetic simulated annealing algorithm is proposed to solve the optimization problem in the second stage and the results are compared to those from the genetic algorithm. A case study is also conducted to demonstrate the effectiveness of the proposed method and algorithm. The results indicate the proposed method can provide practical and effective solutions that help planners and government agencies make informed refueling station location decisions.

  3. Adjusted peak-flow frequency estimates for selected streamflow-gaging stations in or near Montana based on data through water year 2011: Chapter D in Montana StreamStats

    Science.gov (United States)

    Sando, Steven K.; Sando, Roy; McCarthy, Peter M.; Dutton, DeAnn M.

    2016-04-05

    The climatic conditions of the specific time period during which peak-flow data were collected at a given streamflow-gaging station (hereinafter referred to as gaging station) can substantially affect how well the peak-flow frequency (hereinafter referred to as frequency) results represent long-term hydrologic conditions. Differences in the timing of the periods of record can result in substantial inconsistencies in frequency estimates for hydrologically similar gaging stations. Potential for inconsistency increases with decreasing peak-flow record length. The representativeness of the frequency estimates for a short-term gaging station can be adjusted by various methods including weighting the at-site results in association with frequency estimates from regional regression equations (RREs) by using the Weighted Independent Estimates (WIE) program. Also, for gaging stations that cannot be adjusted by using the WIE program because of regulation or drainage areas too large for application of RREs, frequency estimates might be improved by using record extension procedures, including a mixed-station analysis using the maintenance of variance type I (MOVE.1) procedure. The U.S. Geological Survey, in cooperation with the Montana Department of Transportation and the Montana Department of Natural Resources and Conservation, completed a study to provide adjusted frequency estimates for selected gaging stations through water year 2011.The purpose of Chapter D of this Scientific Investigations Report is to present adjusted frequency estimates for 504 selected streamflow-gaging stations in or near Montana based on data through water year 2011. Estimates of peak-flow magnitudes for the 66.7-, 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities are reported. These annual exceedance probabilities correspond to the 1.5-, 2-, 2.33-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-year recurrence intervals, respectively.The at-site frequency estimates were

  4. A Simulation-Based Framework for the Cooperation of VMS Travel Guidance and Traffic Signal Control

    Directory of Open Access Journals (Sweden)

    Meng Li

    2014-01-01

    Full Text Available Nowadays, both travel guidance systems and traffic signal control systems are quite common for urban traffic management. In order to achieve collaborative effect, different models had been proposed in the last two decades. In recent years, with the development of variable message sign (VMS technology, more and more VMS panels are installed on major arterials to provide highly visible and concise graphs or text messages to drivers, especially in developing countries. To discover drivers’ responses to VMS, we establish a drivers’ en route diversion model according to a stated-preference survey. Basically, we proposed a cooperative mechanism and systematic framework of VMS travel guidance and major arterials signal operations. And then a two-stage nested optimization problem is formulated. To solve this optimization problem, a simulation-based optimization method is adopted to optimize the cooperative strategies with TRANSIMS. The proposed method is applied to the real network of Tianjin City comprising of 30 nodes and 46 links. Simulations show that this new method could well improve the network condition by 26.3%. And analysis reveals that GA with nested dynamic programming is an effective technique to solve the optimization problem.

  5. Evolution of tag-based cooperation on Erdős-Rényi random graphs

    Science.gov (United States)

    Lima, F. W. S.; Hadzibeganovic, Tarik; Stauffer, Dietrich

    2014-12-01

    Here, we study an agent-based model of the evolution of tag-mediated cooperation on Erdős-Rényi random graphs. In our model, agents with heritable phenotypic traits play pairwise Prisoner's Dilemma-like games and follow one of the four possible strategies: Ethnocentric, altruistic, egoistic and cosmopolitan. Ethnocentric and cosmopolitan strategies are conditional, i.e. their selection depends upon the shared phenotypic similarity among interacting agents. The remaining two strategies are always unconditional, meaning that egoists always defect while altruists always cooperate. Our simulations revealed that ethnocentrism can win in both early and later evolutionary stages on directed random graphs when reproduction of artificial agents was asexual; however, under the sexual mode of reproduction on a directed random graph, we found that altruists dominate initially for a rather short period of time, whereas ethnocentrics and egoists suppress other strategists and compete for dominance in the intermediate and later evolutionary stages. Among our results, we also find surprisingly regular oscillations which are not damped in the course of time even after half a million Monte Carlo steps. Unlike most previous studies, our findings highlight conditions under which ethnocentrism is less stable or suppressed by other competing strategies.

  6. Supply Chain Cooperation by Agreed Reduction of Behavior Variability: A Simulation-based Study

    Directory of Open Access Journals (Sweden)

    M. L. Chew Hernandez

    2017-04-01

    Full Text Available Supply chain echelons normally base their operational decisions on average values of the parameters that depend on other members. However, in real-life operation the variability of said parameters decreases the link profits. Thus, a cooperative arrangement may be devised in which a link agrees to reduce the variability of its behavior to enhance the performance of other links, receiving compensation in return. This work shows the application of simulation and decision trees to assess the feasibility of this cooperation scheme, from the perspective of the central link of a three member supply chain. First, the operational parameters of the link are optimized for mean values of the variables set by adjacent members. Then, by simulating the system for different probability distributions of these variables, graphs of the expected link gain versus the variances of the distributions are plotted. The results are incorporated to decision trees to evaluate the collaboration feasibility. It was found that the increased variability of the behavior of one neighboring member decreases the benefit of lowering the variability of the behavior of the other. The manuscript closes with a discussion of the practical viability of this collaboration scheme.

  7. Physical Layer Authentication Enhancement Using Maximum SNR Ratio Based Cooperative AF Relaying

    Directory of Open Access Journals (Sweden)

    Jiazi Liu

    2017-01-01

    Full Text Available Physical layer authentication techniques developed in conventional macrocell wireless networks face challenges when applied in the future fifth-generation (5G wireless communications, due to the deployment of dense small cells in a hierarchical network architecture. In this paper, we propose a novel physical layer authentication scheme by exploiting the advantages of amplify-and-forward (AF cooperative relaying, which can increase the coverage and convergence of the heterogeneous networks. The essence of the proposed scheme is to select the best relay among multiple AF relays for cooperation between legitimate transmitter and intended receiver in the presence of a spoofer. To achieve this goal, two best relay selection schemes are developed by maximizing the signal-to-noise ratio (SNR of the legitimate link to the spoofing link at the destination and relays, respectively. In the sequel, we derive closed-form expressions for the outage probabilities of the effective SNR ratios at the destination. With the help of the best relay, a new test statistic is developed for making an authentication decision, based on normalized channel difference between adjacent end-to-end channel estimates at the destination. The performance of the proposed authentication scheme is compared with that in a direct transmission in terms of outage and spoofing detection.

  8. Goodness-of-fit based secure cooperative spectrum sensing for cognitive radio network.

    Science.gov (United States)

    Vu-Van, Hiep; Koo, Insoo

    2014-01-01

    Cognitive radio (CR) is a promising technology for improving usage of frequency band. Cognitive radio users (CUs) are allowed to use the bands without interference in operation of licensed users. Reliable sensing information about status of licensed band is a prerequirement for CR network. Cooperative spectrum sensing (CSS) is able to offer an improved sensing reliability compared to individual sensing. However, the sensing performance of CSS can be destroyed due to the appearance of some malicious users. In this paper, we propose a goodness-of-fit (GOF) based cooperative spectrum sensing scheme to detect the dissimilarity between sensing information of normal CUs and that of malicious users, and reject their harmful effect to CSS. The empirical CDF will be used in GOF test to determine the measured distance between distributions of observation sample set according to each hypothesis of licensed user signal. Further, the DS theory is used to combine results of multi-GOF tests. The simulation results demonstrate that the proposed scheme can protect the sensing process against the attack from malicious users.

  9. Stereo-vision-based cooperative-vehicle positioning using OCC and neural networks

    Science.gov (United States)

    Ifthekhar, Md. Shareef; Saha, Nirzhar; Jang, Yeong Min

    2015-10-01

    Vehicle positioning has been subjected to extensive research regarding driving safety measures and assistance as well as autonomous navigation. The most common positioning technique used in automotive positioning is the global positioning system (GPS). However, GPS is not reliably accurate because of signal blockage caused by high-rise buildings. In addition, GPS is error prone when a vehicle is inside a tunnel. Moreover, GPS and other radio-frequency-based approaches cannot provide orientation information or the position of neighboring vehicles. In this study, we propose a cooperative-vehicle positioning (CVP) technique by using the newly developed optical camera communications (OCC). The OCC technique utilizes image sensors and cameras to receive and decode light-modulated information from light-emitting diodes (LEDs). A vehicle equipped with an OCC transceiver can receive positioning and other information such as speed, lane change, driver's condition, etc., through optical wireless links of neighboring vehicles. Thus, the target vehicle position that is too far away to establish an OCC link can be determined by a computer-vision-based technique combined with the cooperation of neighboring vehicles. In addition, we have devised a back-propagation (BP) neural-network learning method for positioning and range estimation for CVP. The proposed neural-network-based technique can estimate target vehicle position from only two image points of target vehicles using stereo vision. For this, we use rear LEDs on target vehicles as image points. We show from simulation results that our neural-network-based method achieves better accuracy than that of the computer-vision method.

  10. Performance Analyses of Renewable and Fuel Power Supply Systems for Different Base Station Sites

    Directory of Open Access Journals (Sweden)

    Josip Lorincz

    2014-11-01

    Full Text Available Base station sites (BSSs powered with renewable energy sources have gained the attention of cellular operators during the last few years. This is because such “green” BSSs impose significant reductions in the operational expenditures (OPEX of telecom operators due to the possibility of on-site renewable energy harvesting. In this paper, the green BSSs power supply system parameters detected through remote and centralized real time sensing are presented. An implemented sensing system based on a wireless sensor network enables reliable collection and post-processing analyses of many parameters, such as: total charging/discharging current of power supply system, battery voltage and temperature, wind speed, etc. As an example, yearly sensing results for three different BSS configurations powered by solar and/or wind energy are discussed in terms of renewable energy supply (RES system performance. In the case of powering those BSS with standalone systems based on a fuel generator, the fuel consumption models expressing interdependence among the generator load and fuel consumption are proposed. This has allowed energy-efficiency comparison of the fuel powered and RES systems, which is presented in terms of the OPEX and carbon dioxide (CO2 reductions. Additionally, approaches based on different BSS air-conditioning systems and the on/off regulation of a daily fuel generator activity are proposed and validated in terms of energy and capital expenditure (CAPEX savings.

  11. An Optimal Charging Strategy for PV-Based Battery Swapping Stations in a DC Distribution System

    Directory of Open Access Journals (Sweden)

    Shengjun Wu

    2017-01-01

    Full Text Available Photovoltaic- (PV- based battery swapping stations (BSSs utilize a typical integration of consumable renewable resources to supply power for electric vehicles (EVs. The charging strategy of PV-based BSSs directly influences the availability, cost, and carbon emissions of the swapping service. This paper proposes an optimal charging strategy to improve the self-consumption of PV-generated power and service availability while considering forecast errors. First, we introduce the typical structure and operation model of PV-based BSSs. Second, three indexes are presented to evaluate operational performance. Then, a particle swarm optimization (PSO algorithm is developed to calculate the optimal charging power and to minimize the charging cost for each time slot. The proposed charging strategy helps decrease the impact of forecast uncertainties on the availability of the battery swapping service. Finally, a day-ahead operation schedule, a real-time decision-making strategy, and the proposed PSO charging strategy for PV-based BSSs are simulated in a case study. The simulation results show that the proposed strategy can effectively improve the self-consumption of PV-generated power and reduce charging cost.

  12. Double Station Cooperative Reconnaissance and Positioning Error Analysis%双机协同交叉定位算法及误差分析

    Institute of Scientific and Technical Information of China (English)

    贺刚; 赵雷鸣; 刘昊; 樊雷; 黄秦煌

    2015-01-01

    针对双机协同对地面或海面缓慢移动目标进行精确定位的需求,给出了双站协同定位的工作原理、定位流程及模型,从理论上推导了三维空间中双机协同交叉定位算法中的误差关系式,并详细分析了影响定位误差的各种因素,最后通过仿真验证了理论推导的正确性.研究结果为双机协同对敌目标精确定位的实际应用提供了理论支持.%Be demand for precise positioning dual synergistic move slowly on the ground or sea targets,this paper presents a dual station co-location of works,positioning processes and models, Theoretically derived from three-dimensional space dual synergistic cross-localization algorithm errors in the relationship,And a detailed analysis of the various factors influences the positioning error,and finally the simulation verify the theoretical derivation is correct. The results for the two-machine collaboration pinpoint enemy targets practical application provides theoretical support.

  13. Base station MAC with APRMA protocol for broadband multimedia ATM in micro/pico-cellular mobile networks

    DEFF Research Database (Denmark)

    Le, Khanh Hoang; Nielsen, Søren Nørskov; Dittmann, Lars

    1998-01-01

    The concept for a wireless ATM access system that enables seamless mobile connectivity to the B-ISDN is presented. It is based on small, low cost and intelligent base stations running a medium access control (MAC) protocol using adaptive packet reservation multiple access (APRMA). Both the princi...

  14. Network analysis of geomagnetic substorms using the SuperMAG database of ground-based magnetometer stations

    CERN Document Server

    Dods, J; Gjerloev, J W

    2016-01-01

    The overall morphology and dynamics of magnetospheric substorms is well established in terms of the observed qualitative auroral features seen in ground-based magnetometers. This paper focuses on the quantitative characterization of substorm dynamics captured by ground-based magnetometer stations. We present the first analysis of substorms using dynamical networks obtained from the full available set of ground-based magnetometer observations in the Northern Hemisphere. The stations are connected in the network when the correlation between the vector magnetometer time series from pairs of stations within a running time window exceeds a threshold. Dimensionless parameters can then be obtained that characterize the network and by extension, the spatiotemporal dynamics of the substorm under observation. We analyze four isolated substorm test cases as well as a steady magnetic convection (SMC) event and a day in which no substorms occur. These test case substorms are found to give a consistent characteristic netwo...

  15. Ground-based aerosol measurements during CHARMEX/ADRIMED campaign at Granada station

    Science.gov (United States)

    Granados-Muñoz, Maria Jose; Bravo-Aranda, Juan Antonio; Navas-Guzman, Francisco; Guerro-Rascado, Juan Luis; Titos, Gloria; Lyamani, Hassan; Valenzuela, Antonio; Cazorla, Alberto; Olmo, Francisco Jose; Mallet, Marc; Alados-Arboledas, Lucas

    2015-04-01

    In the framework of ChArMEx/ADRIMED (Chemistry-Aerosol Mediterranean Experiment, http://charmex.lsce.ipsl.fr/; Aerosol Direct Radiative Impact on the regional climate in the MEDiterranean region) projects, a field experiment based on in situ and remote sensing measurements from surface and airborne platforms was performed. The ADRIMED project aimed to capture the high complexity of the Mediterranean region by using an integrated approach based on intensive experimental field campaign and spaceborne observations, radiative transfer calculations and climate modelling with Regional Climate Models better adapted than global circulation models. For this purpose, measurements were performed at different surface super-sites (including Granada station) over the Occidental Mediterranean region during summer 2013 for creating an updated database of the physical, chemical, optical properties and the vertical distribution of the major "Mediterranean aerosols". Namely, measurements at Granada station were performed on 16 and 17 July 2013, in coincidence with the overpasses of the ATR aircraft over the station. The instrumentation used for the campaign includes both remote sensing instruments (a multiwavelength Raman lidar and a sun photometer) and in-situ measurements (a nephelometer, a Multi-Angle Absorption Photometer (MAAP), an Aerodynamic particle sizer (APS), a high volume sampler of PM10 and an aethalometer). During the measurement period a mineral dust event was detected, with similar dust load on both days. According to in-situ measurements, the event reached the surface level on 16 of June. Vertically resolved lidar measurements indicated presence of mineral dust layers up to 5 km asl both on 16 and 17 June 2013. Temporal evolution analysis indicated that on 17 June the dust layer decoupled from the boundary layer and disappeared around 14:00 UTC. In addition, lidar and sun-photometer data were used to retrieve volume concentration profiles by means of LIRIC (Lidar

  16. Fiber-distributed Ultra-wideband noise radar with steerable power spectrum and colorless base station.

    Science.gov (United States)

    Zheng, Jianyu; Wang, Hui; Fu, Jianbin; Wei, Li; Pan, Shilong; Wang, Lixian; Liu, Jianguo; Zhu, Ninghua

    2014-03-10

    A fiber-distributed Ultra-wideband (UWB) noise radar was achieved, which consists of a chaotic UWB noise source based on optoelectronic oscillator (OEO), a fiber-distributed transmission link, a colorless base station (BS), and a cross-correlation processing module. Due to a polarization modulation based microwave photonic filter and an electrical UWB pass-band filter embedded in the feedback loop of the OEO, the power spectrum of chaotic UWB signal could be shaped and notch-filtered to avoid the spectrum-overlay-induced interference to the narrow band signals. Meanwhile, the wavelength-reusing could be implemented in the BS by means of the distributed polarization modulation-to-intensity modulation conversion. The experimental comparison for range finding was carried out as the chaotic UWB signal was notch-filtered at 5.2 GHz and 7.8 GHz or not. Measured results indicate that space resolution with cm-level could be realized after 3-km fiber transmission thanks to the excellent self-correlation property of the UWB noise signal provided by the OEO. The performance deterioration of the radar raised by the energy loss of the notch-filtered noise signal was negligible.

  17. Comparison of two human-machine-interfaces for cooperative maneuver-based driving.

    Science.gov (United States)

    Franz, Benjamin; Kauer, Michaela; Blanke, Anton; Schreiber, Michael; Bruder, Ralph; Geyer, Sebastian

    2012-01-01

    In the project "Conduct-by-Wire" which is founded by the German Research Foundation (DFG) cooperative maneuver based driving is examined. In this paper two different input devices (gesture recognition and tactile touch display) are compared in a simulator study with 29 participants. It shows that the major advantage of the gesture recognition is that there is no need for the driver to take his gaze off the road. In contrast, the number of gazes at the tactile touch display is significantly higher. The major advantage of the tactile touch display is that no input errors occurred during the test drives. Conversely, the gesture recognition was significantly worse. Nevertheless, further work is needed to decide which input device is the best.

  18. Cooperative Reputation Index Based Selfish Node Detection and Prevention System for Mobile Ad hoc Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Arsalan Paracha

    2012-04-01

    Full Text Available In Ad hoc networks every node plays an important part in the transmission of packets from sender to receiver. Most of the time packet delivery ratio of these networks depends on the behavior of intermediate nodes. Sometimes these intermediate nodes cooperate and forward the packets of their neighbor and some time they simply drop their packets and cheat their neighbors. We present a solution that not only detect these selfish nodes but also punish these nodes so that they avoid such misbehavior in future. To this account, we use an agent “Neighbor Monitor”, running on every node, to monitor the traffic of neighbors and assign a value called “Reputation Index”, associated with each node, based on its behavior.

  19. Distributed non-cooperative robust MPC based on reduced-order models

    Institute of Scientific and Technical Information of China (English)

    Yushen LONG; Shuai LIU; Lihua XIE; Karl Henrik JOHANSSON

    2016-01-01

    In this paper, a non-cooperative distributed MPC algorithm based on reduced order model is proposed to stabilize large-scale systems. The large-scale system consists of a group of interconnected subsystems. Each subsystem can be partitioned into two parts:measurable part, whose states can be directly measured by sensors, and the unmeasurable part. In the online computation phase, only the measurable dynamics of the corresponding subsystem and neighbour-to-neighbour communication are necessary for the local controller design. Satisfaction of the state constraints and the practical stability are guaranteed while the complexity of the optimization problem is reduced. Numerical examples are given to show the effectiveness of this algorithm.

  20. Individual wealth-based selection supports cooperation in spatial public goods games

    CERN Document Server

    Chen, Xiaojie

    2016-01-01

    In a social dilemma game group members are allowed to decide if they contribute to the joint venture or not. As a consequence, defectors, who do not invest but only enjoy the mutual benefit, prevail and the system evolves onto the tragedy of the common state. This unfortunate scenario can be avoided if participation is not obligatory but only happens with a given probability. But what if we also consider a player's individual wealth when to decide about participation? To address this issue we propose a model in which the probabilistic participation in the public goods game is combined with a conditional investment mode that is based on individual wealth: if a player's wealth exceeds a threshold value then it is qualified and can participate in the joint venture. Otherwise, the participation is forbidden in the investment interactions. We show that if only probabilistic participation is considered, spatially structured populations cannot support cooperation better than well-mixed populations where full defecti...

  1. Differential space-time modulation based on orthogonal design for cooperative network

    Institute of Scientific and Technical Information of China (English)

    Ding Sheng; Yan Kai; Qiu Yunzhou; Zhu Minghua; Liu Haitao

    2008-01-01

    Differential modulation was widely used for wireless networks in which channel estimation was difficult. Based on orthogonal design, a novel distributed differential space-time coding/decoding scheme for M-PSK modulations was proposed, which had a high code rate of 2/3 and second-order diversity for the two-user cooperative networks. The performance of decode-and-forward (DF) protocols was evaluated. Simulations show that the differential space-time modulation scheme in this paper has better bit error rate (BER) performance or higher code rate than the schemes proposed by Tarasak and Wang when interuser channel states are good enough. The impacts of transmission error between two users for the whole system BER performance were also investigated.

  2. Assessing the value of cooperation and information exchange in large water resources systems by agent-based optimization

    Science.gov (United States)

    Giuliani, M.; Castelletti, A.

    2013-07-01

    Many large-scale water resources systems, especially in transboundary contexts, are characterized by the presence of several and conflicting interests and managed by multiple, institutionally independent decision makers. These systems are often studied adopting a centralized approach based on the assumption of full cooperation and information exchange among the involved parties. Such a perspective is conceptually interesting to quantify the best achievable performance but might have little practical impact given the real political and institutional setting. In this work, we propose a novel decision-analytic framework based on multiagent systems to model and analyze different levels of cooperation and information exchange among multiple decision makers. The Zambezi River basin is used as a case study. According to the proposed agent-based optimization approach, each agent represents a decision maker, whose decisions are defined by an explicit optimization problem considering only the agent's local interests. The economic value of information exchange is estimated comparing a noncooperative setting, where agents act independently, with the first basic level of cooperation, i.e., coordination, characterized by full information exchange. The economic value of cooperation is also estimated by comparison with the ideal, fully cooperative management of the system. Results show that coordination, obtained with complete information exchange, allows the downstream agents to better adapt to the upstream behaviors. The impact of information exchange depends on the objective considered, and we show coordination to be particularly beneficial to environmental interests.

  3. Optimal Allocation of Changing Station for Electric Vehicle Based on Queuing Theory

    Directory of Open Access Journals (Sweden)

    Yagang Zhang

    2016-11-01

    Full Text Available Electric vehicle as the main development direction of the future automotive industry, has gained attention worldwide. The rationality of the planning and construction of the power station, as the foundation of energy supply, is an important premise for the development of electric vehicles. In full consideration of the electric demand and electricity consumption, this paper proposes a new construction mode in which charging station and centralized charging station are appropriately combined and presents a location optimization model. Not only can this model be applied to determine the appropriate location for the power station, but it can use the queuing theory to determine the optimal number of power equipment, with which we can achieve the minimum costs. Finally, taking a certain city as an example, the optimum plan for power station is calculated by using this model, which provides an important reference for the study of electric vehicle infrastructure planning.

  4. Hard Decision Fusion based Cooperative Spectrum Sensing in Cognitive Radio System

    Directory of Open Access Journals (Sweden)

    N. Armi N.M. Saad

    2013-09-01

    Full Text Available Cooperative spectrum sensing was proposed to combat fading, noise uncertainty, shadowing, and even hidden node problem due to primary users (PUs activity that is not spatially localized. It improves the probability of detection by collaborating to detect PUs signal in cognitive radio (CR system as well. This paper studies cooperative spectrum sensing and signal detection in CR system by implementing hard decision combining in data fusion centre. Through computer simulation, we evaluate the performances of cooperative spectrum sensing and signal detection by employing OR and AND rules as decision combining. Energy detector is used to observe the presence of primary user (PU signal. Those results are compared to non-cooperative signal detection for evaluation. They show that cooperative technique has better performance than non-cooperative. Moreover, signal to noise ratio (SNR with greater than or equal 10 dB and 15 collaborated users in CR system has optimal value for probability of detection.

  5. Long-lead station-scale prediction of hydrological droughts in South Korea based on bivariate pattern-based downscaling

    Science.gov (United States)

    Sohn, Soo-Jin; Tam, Chi-Yung

    2016-05-01

    Capturing climatic variations in boreal winter to spring (December-May) is essential for properly predicting droughts in South Korea. This study investigates the variability and predictability of the South Korean climate during this extended season, based on observations from 60 station locations and multi-model ensemble (MME) hindcast experiments (1983/1984-2005/2006) archived at the APEC Climate Center (APCC). Multivariate empirical orthogonal function (EOF) analysis results based on observations show that the first two leading modes of winter-to-spring precipitation and temperature variability, which together account for ~80 % of the total variance, are characterized by regional-scale anomalies covering the whole South Korean territory. These modes were also closely related to some of the recurrent large-scale circulation changes in the northern hemisphere during the same season. Consistent with the above, examination of the standardized precipitation evapotranspiration index (SPEI) indicates that drought conditions in South Korea tend to be accompanied by regional-to-continental-scale circulation anomalies over East Asia to the western north Pacific. Motivated by the aforementioned findings on the spatial-temporal coherence among station-scale precipitation and temperature anomalies, a new bivariate and pattern-based downscaling method was developed. The novelty of this method is that precipitation and temperature data were first filtered using multivariate EOFs to enhance their spatial-temporal coherence, before being linked to large-scale circulation variables using canonical correlation analysis (CCA). To test its applicability and to investigate its related potential predictability, a perfect empirical model was first constructed with observed datasets as predictors. Next, a model output statistics (MOS)-type hybrid dynamical-statistical model was developed, using products from nine one-tier climate models as inputs. It was found that, with model sea

  6. Simulation of bidirectional pedestrian flow in transfer station corridor based on multi forces

    Institute of Scientific and Technical Information of China (English)

    周雪梅; 纪翔峰; 黄凰; 杨晓光

    2014-01-01

    A good understanding of pedestrian movement in the transfer corridor is vital for the planning and design of the station, especially for efficiency and safety.A multi-force vector grid model was presented to simulate the movement of bidirectional pedestrian flow based on cellular automata and forces between pedestrians. The model improves rule-based characteristics of cellular automata, details forces between pedestrians and solves pedestrian collisions by a several-step updating method to simulate pedestrian movements. Two general scenarios in corridor were simulated. One is bidirectional pedestrian flow simulation with isolation facility, and the other is bidirectional pedestrian flow simulation without isolation facility, where there exists disturbance in the middle. Through simulation, some facts can be seen that pedestrians in the case with isolation facility have the largest speed and pedestrians in the case without isolation facility have the smallest speed; pedestrians in the case of unidirectional flow have the largest volume and pedestrians in the case of without isolation facility have the smallest volume.

  7. High precision mobile location framework and its service based on virtual reference station of GPS

    Science.gov (United States)

    Liu, Chun; Sun, Liangyu; Yao, Lianbi

    2008-10-01

    The wireless communication technology and space technology are synchronously developed in recent years, which bring up the development of location based service (LBS). At present, many location technology methods were developed. However, all these methods can only provide a relative poor location precision and depend on high cost. The technology of Virtual Reference Station (VRS) of GPS is then involved in this paper. One of the objective in this paper is aim to give the LBS position structure to improve the mobile location position when a mobile position instrument is connected with VRS network. The cheaper GPS built-in Personal Designer Aid (PDA) is then used to achieve a higher precision by using RTCM data from existing VRS network. In order to obtain a high precision position when using the low-cost GPS receiver as a rover, the infrusture of the mobile differential correction system is then put forward. According to network transportation of RTCM via internet protocol (NTRIP), the message is communicated through wireless network, such as GPRS, CDMA and so on. The rough coordinate information is sent to VRS control center continuously, and then the VRS correction information is replied to rover in the data format of RTCM3.1. So the position will be updated based on mathematic solution after the decoding of RTCM3.1 data. The thought of LBS position can improve the precision, and can speed the LBS.

  8. Attitude Estimation for In-Service Base Station Antenna Using Downlink Channel Fading Statistics

    Directory of Open Access Journals (Sweden)

    Cen Ling

    2015-01-01

    Full Text Available A maximum-likelihood-estimation method is proposed for extracting the attitude of a sectoring base station (BS antenna by using the received signal strengths observed by multiple user equipments (UEs in this contribution. This method calculates the likelihood function of the antenna attitude derived by taking into account the multiscale fading statistics, that is, path loss, shadowing, and multipath fading. Depending on whether a calibration result of these fading statistics is available or not, the proposed method can be utilized in either calibration-based estimation (CBE or calibration-free estimation (CFE approaches. The performance of both methods is evaluated by Monte-Carlo simulations and real experiments. The results obtained demonstrate that the estimation accuracy of both CBE and CFE approaches increases when the percentage of UEs in the line-of-sight (LoS condition among all available UEs increases and, moreover, the total number of UEs has no significant impact on the estimation accuracy. Furthermore, the CFE exhibits more robust performance than the CBE particularly in the case where the calibration results involve uncertainties.

  9. Broadcast Network Coverage with Multicell Cooperation

    Directory of Open Access Journals (Sweden)

    Hongxiang Li

    2010-01-01

    Full Text Available Multicell cooperation has been identified as one of the underlying principles for future wireless communication systems. This paper studies the benefits of multicell cooperation in broadcast TV network from an information theoretical perspective. We define outage capacity as the figure of merit and derive the broadcast coverage area to evaluate such system. Specifically, we calculate the broadcast coverage area with given common information rate and outage probabilities when multiple base stations collaboratively transmit the broadcast signals. For the general MIMO case where receivers have multiple antennas, we provide simulation results to illustrate the expanded coverage area. In all cases, our results show that the coverage of a TV broadcast network can be significantly improved by multicell cooperation.

  10. GAMBARAN GANGGUAN CEMAS MASYARAKAT DI SEKITAR MENARA BASE TRANCEIVER STATION/BTS DI BANDUNG DAN JAKARTA

    Directory of Open Access Journals (Sweden)

    Athena Anwar

    2015-01-01

    Full Text Available AbstractA research on Health Effect of Electromagnetic Fields to People Arround The Base Tranceiver Stations (BTSs in Jakarta and Bandung was conducted to study the influence of BTS existence on the residents’ mental health condition.The research design was cross-sectional The number of sample was 655 people scattered in 10 BTSs. The data was collected through interviews using Mini International Neuropsychiatric Interview (MINI questionnaires, conducted by researchers of Center for Public Health Intervention Technology, NIHRD. Data processing and analysis were performed bivariate between the house’s distances from BTSs and the occurrences of anxiety disorder. The results showed that 64,8% of respondents in Bandung and 57,8% of respondents in Jakarta have a general health complaints such as dizziness/headaches, cough and fever, and suffering from degenerative diseases such as high blood pressure, stroke, and diabetes mellitus (DM. Specially for mental health, there is a significant association between respondents’ anxiety disorders and the distance of their house from the BTSs (p<0,05. The proportion of respondents suffering from anxiety disorder is higher for respondents whose house is located less than 100 meters from the BTSs than those who have their house at a greater distance (over 100 meters. The respondents living near BTSs in Bandung and Jakarta have general health problems. The anxiety disorder is most likely triggered by the BTSs existence near their house.Keywords : Base Transceiver Station, Radiation, Anxiety DisorderAbstrakTelah dilakukan Penelitian Pengaruh Medan Elektromagnetik Terhadap Kesehatan Masyarakat Di Sekitar Menara Pemancar Telepon Seluler (BTS di Jakarta dan Bandung, Disain dari penelitian adalah potong lintang dengan jumlah sampel 655 orang yang tersebar di sekitar 10 BTS. Pengumpulan data dilakukan dengan cara wawancara menggunakan kuesioner Mini International of Neuropsychiatric Interview (MINI oleh peneliti

  11. Peak-flow frequency analyses and results based on data through water year 2011 for selected streamflow-gaging stations in or near Montana: Chapter C in Montana StreamStats

    Science.gov (United States)

    Sando, Steven K.; McCarthy, Peter M.; Dutton, DeAnn M.

    2016-04-05

    Chapter C of this Scientific Investigations Report documents results from a study by the U.S. Geological Survey, in cooperation with the Montana Department of Transportation and the Montana Department of Natural Resources, to provide an update of statewide peak-flow frequency analyses and results for Montana. The purpose of this report chapter is to present peak-flow frequency analyses and results for 725 streamflow-gaging stations in or near Montana based on data through water year 2011. The 725 streamflow-gaging stations included in this study represent nearly all streamflowgaging stations in Montana (plus some from adjacent states or Canadian Provinces) that have at least 10 years of peak-flow records through water year 2011. For 29 of the 725 streamflow-gaging stations, peak-flow frequency analyses and results are reported for both unregulated and regulated conditions. Thus, peak-flow frequency analyses and results are reported for a total of 754 analyses. Estimates of peak-flow magnitudes for 66.7-, 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities are reported. These annual exceedance probabilities correspond to 1.5-, 2-, 2.33-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-year recurrence intervals.

  12. Chinese Meridian Project and its international cooperation

    Science.gov (United States)

    Yang, Guotao; Wang, Chi; Jiao, Jing; Liu, Zhengkuan

    2016-07-01

    Meridian Space Weather Monitoring Project (Meridian Project) has a Chinese multi-station chain along 120ºE longitude to monitor space environment, starting from Mohe, the most northern station in China, through Beijing, Wuhan and extended to Zhongshan station in the Antarctic. The Meridian Project consists of 15 observational stations, the instruments includes magnetometer, ionosonde, incoherent scattering radar, HF back-scattering radar, VLF receiver, LIDAR, and Fabry-Perot interferometer (FPI). The Meridian Project has finished its construction phase in 2012, and started its running phase in 2013. Until now, more than 100 papers have been published by using Meridian Project data. The Meridian Project also provide service for Chinese space activity. The International Space Weather Meridian Circle Program (IMCP) is based upon the Meridian Project. With the international cooperation around this circle, we should take full advantage of foreign resources. The Meridian Project will be extended to Russian, though many Southeast Asia countries such as Australia, and so on. Furthermore, it will be extended to the countries located in the west hemisphere near 60° meridian. The first and only ground-based global space weather monitoring circle will be formed. Cooperation agreements for IMCP have been signed, and we will develop IMCP more deeply in the 2016 COSPAR meeting.

  13. Analysis on influencing factors of EV charging station planning based on AHP

    Science.gov (United States)

    Yan, F.; Ma, X. F.

    2016-08-01

    As a new means of transport, electric vehicle (EV) is of great significance to alleviate the energy crisis. EV charging station planning has a far-reaching significance for the development of EV industry. This paper analyzes the impact factors of EV charging station planning, and then uses the analytic hierarchy process (AHP) to carry on the further analysis to the influencing factors, finally it gets the weight of each influence factor, and provides the basis for the evaluation scheme of the planning of charging stations for EV.

  14. Multi-User Cooperative Diversity through Network Coding Based on Classical Coding Theory

    CERN Document Server

    Rebelatto, João Luiz; Li, Yonghui; Vucetic, Branka

    2010-01-01

    In this work, we propose and analyze a generalized construction of distributed network codes for a network consisting of M users sending different information to a common base station through independent block fading channels. The aim is to increase the diversity order of the system without reducing its code rate. The proposed scheme, called generalized dynamic-network codes (GDNC), is a generalization of the dynamic-network codes (DNC) recently proposed by Xiao and Skoglund. The design of the network codes that maximize the diversity order is recognized as equivalent to the design of linear block codes over a nonbinary finite field under the Hamming metric. We prove that adopting a systematic generator matrix of a maximum distance separable block code over a sufficiently large finite field as the network transfer matrix is a sufficient condition for full diversity order under link failure model. The proposed generalization offers a much better tradeoff between rate and diversity order compared to the DNC. An...

  15. Generalized Distributed Network Coding Based on Nonbinary Linear Block Codes for Multi-User Cooperative Communications

    CERN Document Server

    Rebelatto, João Luiz; Li, Yonghui; Vucetic, Branka

    2010-01-01

    In this work, we propose and analyze a generalized construction of distributed network codes for a network consisting of M users sending different information to a common base station through independent block fading channels. The aim is to increase the diversity order of the system without reducing its code rate. The proposed scheme, called generalized dynamic network codes (GDNC), is a generalization of the dynamic network codes (DNC) recently proposed by Xiao and Skoglung. The design of the network codes that maximizes the diversity order is recognized as equivalent to the design of linear block codes over a nonbinary finite field under the Hamming metric. The proposed scheme offers a much better tradeoff between rate and diversity order. An outage probability analysis showing the improved performance is carried out, and computer simulations results are shown to agree with the analytical results.

  16. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station installed on buildings in Serbia.

    Science.gov (United States)

    Koprivica, Mladen; Slavkovic, Vladimir; Neskovic, Natasa; Neskovic, Aleksandar

    2016-03-01

    As a result of dense deployment of public mobile base stations, additional electromagnetic (EM) radiation occurs in the modern human environment. At the same time, public concern about the exposure to EM radiation emitted by such sources has increased. In order to determine the level of radio frequency radiation generated by base stations, extensive EM field strength measurements were carried out for 664 base station locations, from which 276 locations refer to the case of base stations with antenna system installed on buildings. Having in mind the large percentage (42 %) of locations with installations on buildings, as well as the inevitable presence of people in their vicinity, a detailed analysis of this location category was performed. Measurement results showed that the maximum recorded value of total electric field strength has exceeded International Commission on Non-Ionizing Radiation Protection general public exposure reference levels at 2.5 % of locations and Serbian national reference levels at 15.6 % of locations. It should be emphasised that the values exceeding the reference levels were observed only outdoor, while in indoor total electric field strength in no case exceeded the defined reference levels.

  17. Regulation during Cooperative and Collaborative Learning: A Theory-Based Review of Terms and Concepts

    Science.gov (United States)

    Schoor, Cornelia; Narciss, Susanne; Körndle, Hermann

    2015-01-01

    This article reviews the terms and concepts that have been used for describing regulation of learning during cooperative and collaborative learning and suggests differentiating them on the basis of which parts of a regulatory feedback loop model are being shared. During cooperative and collaborative learning, not only self-regulation but also the…

  18. Service Station Evaluation Problem in Catering Service of High-Speed Railway: A Fuzzy QFD Approach Based on Evidence Theory

    Directory of Open Access Journals (Sweden)

    Xin Wu

    2015-01-01

    Full Text Available Catering Service of High-Speed Railway (CSHR starts at suppliers, includes distribution centers and service stations in cities, and ends at cabinets in high-speed trains. In Distribution System Design (DSD Problem for CSHR, it is critical to evaluate the alternatives of service stations, which is termed as Service Station Evaluation Problem in Catering Service of High-speed Railway (SSEP-CSHR. As a preparation work for DSD, SSEP-CSHR needs to be solved without detailed information and being accompanied with uncertainty. Fuzzy Quality Function Deployment (F-QFD has been given in the literatures to deal with vagueness in Facility Location Evaluation (FLE. However, SSEP-CSHR that includes identifying and evaluating stations requires not only dealing with the vague nature of assessments but also confirming them. Based on evidence theory, this paper introduces the framework to give the truth of proposition “x is A.” Then it is incorporated into a two-phase F-QFD with an approximate reasoning to enable the truth of the decisions to be measured. A case study that refers to 85 alternative stations on Chinese high-speed railway will be carried out to verify the proposed method. Analysis shows that the proposed evaluation method enhances scientific credibility of FLE and allows decision makers to express how much is known.

  19. Cooperation in environmental protection. The economics of green trade, market-based instruments and community involvement

    Energy Technology Data Exchange (ETDEWEB)

    Roettgers, Dirk

    2013-12-18

    The Millennium Development Goals (United Nations, 2000) and, by extension, such efforts as the Convention on Biological Diversity and the Kyoto Protocol (Kyoto Protocol, 1997), present mankind with a challenge that can only be overcome through cooperation. Cooperative policies are necessary from the highest level, i.e. international policies and treaties, to regional and national agreements, down to the local level, where policies are actually enacted. To close some gaps in the understanding of applicable policy instruments, this dissertation looks at a few key topics of environmental protection with implications for market-based instruments. The five different research areas are (1) EU bioenergy trade, (2) Clean Development Mechanism (CDM), (3) comparison of the effectiveness of product certification, ecosystem certification and offset mechanisms in wetland ecosystems, (4) international market-based instruments for African protected areas and (5) local stakeholder decision making in rural ecosystems of developing countries. Bioenergy consumption, production and trade have been increasing worldwide in the recent decade, mostly due to demand from EU countries and the USA. Taking the example of the EU, it is questionable if these trade flows are caused mainly by EU trade rules or targeted bioenergy policies. A sector-specific analysis taking industry patterns into consideration is necessary to evaluate the impact of these two policy areas on trade flows. A common way to analyze trade flows is the gravity model, which is employed here. This dissertation finds out why that is by using a gravity model to analyze flows of Certified Emission Reductions (CERs) between host and financier countries. The special roles of foreign direct investments (FDI), official development aid (ODA) and trade are scrutinized closely in this context. Findings show that FDI, ODA and trade have a positive influence on project attraction, even when holding determinants of these factors constant

  20. Vibration-Based Damage Detection in Beams by Cooperative Coevolutionary Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Kittipong Boonlong

    2014-03-01

    Full Text Available Vibration-based damage detection, a nondestructive method, is based on the fact that vibration characteristics such as natural frequencies and mode shapes of structures are changed when the damage happens. This paper presents cooperative coevolutionary genetic algorithm (CCGA, which is capable for an optimization problem with a large number of decision variables, as the optimizer for the vibration-based damage detection in beams. In the CCGA, a minimized objective function is a numerical indicator of differences between vibration characteristics of the actual damage and those of the anticipated damage. The damage detection in a uniform cross-section cantilever beam, a uniform strength cantilever beam, and a uniform cross-section simply supported beam is used as the test problems. Random noise in the vibration characteristics is also considered in the damage detection. In the simulation analysis, the CCGA provides the superior solutions to those that use standard genetic algorithms presented in previous works, although it uses less numbers of the generated solutions in solution search. The simulation results reveal that the CCGA can efficiently identify the occurred damage in beams for all test problems including the damage detection in a beam with a large number of divided elements such as 300 elements.

  1. Real-Time Communication Support for Cooperative, Infrastructure-Based Traffic Safety Applications

    Directory of Open Access Journals (Sweden)

    Annette Böhm

    2011-01-01

    Full Text Available The implementation of ITS (Intelligent Transport Systems services offers great potential to improve the level of safety, efficiency and comfort on our roads. Although cooperative traffic safety applications rely heavily on the support for real-time communication, the Medium Access Control (MAC mechanism proposed for the upcoming IEEE 802.11p standard, intended for ITS applications, does not offer deterministic real-time support, that is, the access delay to the common radio channel is not upper bounded. To address this problem, we present a framework for a vehicle-to-infrastructure-based (V2I communication solution extending IEEE 802.11p by introducing a collision-free MAC phase assigning each vehicle an individual priority based on its geographical position, its proximity to potential hazards and the overall road traffic density. Our solution is able to guarantee the timely treatment of safety-critical data, while minimizing the required length of this real-time MAC phase and freeing bandwidth for best-effort services (targeting improved driving comfort and traffic efficiency. Furthermore, we target fast connection setup, associating a passing vehicle to an RSU (Road Side Unit, and proactive handover between widely spaced RSUs. Our real-time MAC concept is evaluated analytically and by simulation based on a realistic task set from a V2I highway merge assistance scenario.

  2. Study of variations of radiofrequency power density from mobile phone base stations with distance.

    Science.gov (United States)

    Ayinmode, B O; Farai, I P

    2013-10-01

    The variations of radiofrequency (RF) radiation power density with distance around some mobile phone base stations (BTSs), in ten randomly selected locations in Ibadan, western Nigeria, were studied. Measurements were made with a calibrated hand-held spectrum analyser. The maximum Global System of Mobile (GSM) communication 1800 signal power density was 323.91 µW m(-2) at 250 m radius of a BTS and that of GSM 900 was 1119.00 µW m(-2) at 200 m radius of another BTS. The estimated total maximum power density was 2972.00 µW m(-2) at 50 m radius of a different BTS. This study shows that the maximum carrier signal power density and the total maximum power density from a BTS may be observed averagely at 200 and 50 m of its radius, respectively. The result of this study demonstrates that exposure of people to RF radiation from phone BTSs in Ibadan city is far less than the recommended limits by International scientific bodies.

  3. What input data are needed to accurately model electromagnetic fields from mobile phone base stations?

    Science.gov (United States)

    Beekhuizen, Johan; Kromhout, Hans; Bürgi, Alfred; Huss, Anke; Vermeulen, Roel

    2015-01-01

    The increase in mobile communication technology has led to concern about potential health effects of radio frequency electromagnetic fields (RF-EMFs) from mobile phone base stations. Different RF-EMF prediction models have been applied to assess population exposure to RF-EMF. Our study examines what input data are needed to accurately model RF-EMF, as detailed data are not always available for epidemiological studies. We used NISMap, a 3D radio wave propagation model, to test models with various levels of detail in building and antenna input data. The model outcomes were compared with outdoor measurements taken in Amsterdam, the Netherlands. Results showed good agreement between modelled and measured RF-EMF when 3D building data and basic antenna information (location, height, frequency and direction) were used: Spearman correlations were >0.6. Model performance was not sensitive to changes in building damping parameters. Antenna-specific information about down-tilt, type and output power did not significantly improve model performance compared with using average down-tilt and power values, or assuming one standard antenna type. We conclude that 3D radio wave propagation modelling is a feasible approach to predict outdoor RF-EMF levels for ranking exposure levels in epidemiological studies, when 3D building data and information on the antenna height, frequency, location and direction are available.

  4. Spherical Projection Based Straight Line Segment Extraction for Single Station Terrestrial Laser Point Cloud

    Directory of Open Access Journals (Sweden)

    ZHANG Fan

    2015-06-01

    Full Text Available Due to the discrete distribution computing errors and lack of adaptability are ubiquitous in the current straight line extraction for TLS data methods. A 3D straight line segment extraction method is proposed based on spherical projection for single station terrestrial laser point clouds. Firstly, horizontal and vertical angles of each laser point are calculated by means of spherical coordinates, intensity panoramic image according to the two angles is generated. Secondly, edges which include straight line features are detected from intensity panoramic image by using of edge detection algorithm. Thirdly, great circles are detected from edges of panoramic image using spherical Hough transform. According to the axiom that a straight line segment in 3D space is a spherical great circle after spherical projection, detecting great circles from spherical projected data sets is essentially detecting straight line segments from 3D data sets without spherical projection. Finally, a robust 3D straight line fitting method is employed to fitting the straight lines and calculating parameters of the straight line segments. Experiments using different data sets and comparison with other methods show the accuracy and applicability of the proposed method.

  5. Wind characteristics on the Yucatan Peninsula based on short term data from meteorological stations

    Energy Technology Data Exchange (ETDEWEB)

    Soler-Bientz, Rolando [CREST, Department of Electronic and Electrical Engineering, Loughborough University, LE11 3TU (United Kingdom); Energy Laboratory, Faculty of Engineering, Autonomous University of Yucatan, Merida, Yucatan (Mexico); Watson, Simon [CREST, Department of Electronic and Electrical Engineering, Loughborough University, LE11 3TU (United Kingdom); Infield, David [Institute of Energy and Environment, University of Strathclyde, Glasgow (United Kingdom)

    2010-04-15

    Due to the availability of sparsely populated and flat open terrain, the Yucatan Peninsula located in eastern Mexico is a promising region from the perspective of wind energy development. Study of the diurnal and seasonal wind resource is an important stage in the move towards commercial exploitation of wind power in this Latin American region. An analysis of the characteristics of the wind resource of the Yucatan Peninsula is presented in this paper, based on 10 min averaged wind speed data from nine meteorological stations, between 2000 and 2007. Hourly and monthly patterns of the main environmental parameters have been examined. Highly directional behaviour was identified that reflects the influence of winds coming from the Caribbean Sea and the Gulf of Mexico. The characteristics of the wind speed variation observed at the studied sites reflected their proximity to the coast and whether they were influenced by wind coming predominantly from over the land or predominantly from over the sea. The atmospheric stability over the eastern seas of the Yucatan Peninsula was also analysed to assess thermal effects for different wind directions. The findings were consistent with the variation in average wind speeds observed at the coastal sites where winds came predominantly from over the sea. The research presented here is to be used as a basis for a wind atlas for the Yucatan Peninsula. (author)

  6. Optimasi Peletakan Base Transceiver Station Di Kabupaten Mojokerto Menggunakan Algoritma Differential Evolution

    Directory of Open Access Journals (Sweden)

    Ahadi Arif Nugraha

    2015-03-01

    Full Text Available Salah satu aspek penting dalam perencanaan infrastruktur jaringan seluler adalah Base Transceiver Station (BTS yang merupakan sebuah pemancar dan penerima sinyal telephone seluler. Di satu sisi, peningkatan jumlah menara memang akan mendukung tercapainya pemenuhan kebutuhan masyarakat terhadap layanan telekomunikasi. Namun di sisi lain, penempatan menara yang  tanpa perencanaan serta koordinasi yang tepat akan menimbulkan jumlah menara yang berlebih sehingga dapat mengganggu estetika lingkungan, tata ruang suatu wilayah, dan radiasi gelombang radio yang tidak terkontrol sehingga sangat mengganggu. Berdasarkan permasalahan diatas, maka dapat diselesaikan dengan cara menyusun suatu master plan yang lengkap dan rinci tentang penataan lokasi menara di Kabupaten Mojokerto untuk lima tahun mendatang. Penataan lokasi menara dilakukan dengan menggunakan algoritma Differential Evolution (DE untuk menemukan solusi penataan menara yang baik berdasarkan luas cakupan area sel yang dihasilkan, kemudian menggunakan software MapInfo sebagai media visualisasi peta lokasi penempatan menara telekomunikasi. Dalam perancangan menara BTS tahun 2019, Kabupaten Mojokerto membutuhkan 106 menara BTS 2G dan 36 menara BTS 3G. Penempatan menara BTS 2G dan 3G menggunakan algoritma differential evolution mampu mengoptimalkan 2,94% dari luas wilayah Kabupaten Mojokerto

  7. Measurement and analysis of radiofrequency radiations from some mobile phone base stations in Ghana.

    Science.gov (United States)

    Amoako, J K; Fletcher, J J; Darko, E O

    2009-08-01

    A survey of the radiofrequency electromagnetic radiation at public access points in the vicinity of 50 cellular phone base stations has been carried out. The primary objective was to measure and analyse the electromagnetic field strength levels emitted by antennae installed and operated by the Ghana Telecommunications Company. On all the sites measurements were made using a hand-held spectrum analyser to determine the electric field level with the 900 and 1800 MHz frequency bands. The results indicated that power densities at public access points varied from as low as 0.01 microW m(-2) to as high as 10 microW m(-2) for the frequency of 900 MHz. At a transmission frequency of 1800 MHz, the variation of power densities is from 0.01 to 100 microW m(-2). The results were found to be in compliant with the International Commission on Non-ionizing Radiological Protection guidance level but were 20 times higher than the results generally obtained for such a practice elsewhere. There is therefore a need to re-assess the situation to ensure reduction in the present level as an increase in mobile phone usage is envisaged within the next few years.

  8. Radiation safety of mobile phones and base stations; Matkapuhelimien ja tukiasemien saeteilyturvallisuus

    Energy Technology Data Exchange (ETDEWEB)

    Jokela, K.; Leszczynski, D.; Paile, W.; Salomaa, S.; Puranen, L.; Hyysalo, P.

    1997-06-01

    The recent expansion of personal telecommunications has led to a rapid increase in the exposure of people to the radio-frequency (RF) radiation. Although the mobile phones are low power devices, the antenna is so close to the head that the local exposure may slightly exceed 2 W/kg, the current exposure limit for the local specific absorption rate SAR for the general public. The increase in the temperature is, however, too small to have any physiological significance. On the basis of experiments with cell cultures it is possible that other biological effects caused by some unknown non-thermal mechanism exist, but thus far there is conclusive biological or epidemiological evidence to suggest any diseases adverse physiological changes below the thermal threshold. The use of a mobile phone by a person wearing a pace-maker, the immunity which against the electromagnetic interference from the mobile phone has not be assured, is not recommended. The exposure caused by the base stations is in almost all practical ceases all below the power density limits for general public. (orig.) (115 refs.).

  9. Effect of Electromagnetic Waves Generated by Base Transiver Station on Liver Enzymes in Female Rats

    Directory of Open Access Journals (Sweden)

    Gholam-Ali Jelodar

    2013-07-01

    Full Text Available Background: This study was investigating the effect of electromagnetic wave generated by mobile and base transceiver station (900 MHz on liver enzymes in both mature and immature female age.Materials and Methods: In this study, 20 rats Sprague Dawley white mature female age 8 to 9 weeks and weight 180 to 200 g and 20 rats immature age 3 to 4 weeks, weight 80 to 100 g, each age group were randomly divided in two groups (control and test. Test groups, were daily for four hours and four different times exposed to electromagnetic waves with signal generator (900 MHz, 5-meter intervals. Control groups were kept at equal condition (themperature and light in laboratory during experiment. After at the end experimental period, blood was collected by heart puncture of all animal. Exposure to EMF generated by BTS had significant effect on liver enzymes composition in mature and immature rats.Results: AST, ALT and ALP in immature-test groups decreased significantly compared with their respective control groups (p<0.05. ALP in mature-test groups increased significantly compared with their respective control groups (p<0.05.Conclusion: These result suggest that exposure to EMF generated by BTS has a deleterious effect on liver enzymes and that this effect is more sever in immature animals.

  10. Life is Short: The Impact of Power States on Base Station Lifetime

    Directory of Open Access Journals (Sweden)

    Luca Chiaraviglio

    2015-12-01

    Full Text Available We study the impact of power state transitions on the lifetime of base stations (BSs in mobile networks. In particular, we propose a model to estimate the lifetime decrease/increase as a consequence of the application of power state changes. The model takes into account both hardware (HW parameters, which depend on the materials used to build the device, and power state parameters, that instead depend on how and when power state transitions take place. More in depth, we consider the impact of different power states when a BS is active, and one sleep mode state when a BS is powered off. When a BS reduces the power consumption, its lifetime tends to increase. However, when a BS changes the power state, its lifetime tends to be decreased. Thus, there is a tradeoff between these two effects. Our results, obtained over universal mobile telecommunication system (UMTS and long term evolution (LTE case studies, indicate the need of a careful management of the power state transitions in order to not deteriorate the BS lifetime, and consequently to not increase the associated reparation/replacement costs.

  11. Comparative international analysis of radiofrequency exposure surveys of mobile communication radio base stations.

    Science.gov (United States)

    Rowley, Jack T; Joyner, Ken H

    2012-01-01

    This paper presents analyses of data from surveys of radio base stations in 23 countries across five continents from the year 2000 onward and includes over 173,000 individual data points. The research compared the results of the national surveys, investigated chronological trends and compared exposures by technology. The key findings from this data are that irrespective of country, the year and cellular technology, exposures to radio signals at ground level were only a small fraction of the relevant human exposure standards. Importantly, there has been no significant increase in exposure levels since the widespread introduction of 3G mobile services, which should be reassuring for policy makers and negate the need for post-installation measurements at ground level for compliance purposes. There may be areas close to antennas where compliance levels could be exceeded. Future potential work includes extending the study to additional countries, development of cumulative exposure distributions and investigating the possibility of linking exposure measurements to population statistics to assess the distribution of exposure levels relative to population percentiles.

  12. A fault diagnosis system for PV power station based on global partitioned gradually approximation method

    Science.gov (United States)

    Wang, S.; Zhang, X. N.; Gao, D. D.; Liu, H. X.; Ye, J.; Li, L. R.

    2016-08-01

    As the solar photovoltaic (PV) power is applied extensively, more attentions are paid to the maintenance and fault diagnosis of PV power plants. Based on analysis of the structure of PV power station, the global partitioned gradually approximation method is proposed as a fault diagnosis algorithm to determine and locate the fault of PV panels. The PV array is divided into 16x16 blocks and numbered. On the basis of modularly processing of the PV array, the current values of each block are analyzed. The mean current value of each block is used for calculating the fault weigh factor. The fault threshold is defined to determine the fault, and the shade is considered to reduce the probability of misjudgments. A fault diagnosis system is designed and implemented with LabVIEW. And it has some functions including the data realtime display, online check, statistics, real-time prediction and fault diagnosis. Through the data from PV plants, the algorithm is verified. The results show that the fault diagnosis results are accurate, and the system works well. The validity and the possibility of the system are verified by the results as well. The developed system will be benefit for the maintenance and management of large scale PV array.

  13. A Radio Resource Management strategy for downlink cooperation in distributed networks

    CERN Document Server

    Pischella, Mylene

    2007-01-01

    Downlink cooperation between Base Stations is a simple, efficient alternative to macrodiversity for providing QoS continuity during mobility in distributed cellular networks. It brings cooperation diversity and only requires data forwarding between Base Stations. This paper presents a strategy for downlink cooperation triggering, resource allocation and power control in an OFDMA-based system. Power control aims at maximizing the equivalent capacity that is achieved thanks to the diversity brought by relaying, while taking into account inter-cell interference. We use an iterative method which dedicates a proportion of the total power to relayed users. Simulation results show that our method increases capacity at any load. It importantly reduces the rejection probability thanks to SIR increase of users at cell's border. The paper also shows that cooperation should be limited to cell-border users for restricting additional resource consumption, and that it should make use of diversity as much as possible.

  14. Risk-based maintenance in network stations; Risikobasert vedlikehold i nettstasjoner

    Energy Technology Data Exchange (ETDEWEB)

    Solum, Geir

    2004-07-01

    The so-called KILE scheme instructs the network owners to give compensation to their customers when the mains go off, in cases for which notification has been given, such as maintenance on network stations. This is an extra cost for the electricity company. The compensation frequently exceeds the technical maintenance costs. Thus, KILE effectively motivates for less maintenance. It is slowly being realized, however, that issues relating to the personal safety for the technicians will play a role long before it becomes economically optimal to service or replace a network station. In particular this is true of the network stations having air-insulated circuit breakers, which was very common up to the 1980s. TEV Nett, a subsidiary of Trondheim Energiverk, has developed a maintenance strategy for network stations that tries to consider risk factors relating to both personnel security and economical risk in a way that is systematic and purpose-built.

  15. Ingroup favoritism and intergroup cooperation under indirect reciprocity based on group reputation

    CERN Document Server

    Masuda, Naoki

    2012-01-01

    Indirect reciprocity in which players cooperate with unacquainted other players having good reputations is a mechanism for cooperation in relatively large populations subjected to social dilemma situations. When the population has group structure, as is often found in social networks, players in experiments are considered to show behavior that deviates from existing theoretical models of indirect reciprocity. First, players often show ingroup favoritism (i.e., cooperation only within the group) rather than full cooperation (i.e., cooperation within and across groups) even though the latter is Pareto efficient. Second, in general, humans approximate outgroup members' personal characteristics, presumably including the reputation used for indirect reciprocity, by a single value attached to the group. Humans use such a stereotypic approximation, a phenomenon known as outgroup homogeneity in social psychology. I propose a model of indirect reciprocity in populations with group structure to examine the possibility ...

  16. UV climatology at Palmer Station, Antarctica, based on Version 2 NSF network data

    Science.gov (United States)

    Bernhard, Germar; Booth, Charles R.; Ehramjian, James C.

    2005-08-01

    Spectral ultraviolet (UV) and visible irradiance has been measured at Palmer Station, Antarctica, between 1988 and 2004 with a SUV-100 spectroradiometer. The instrument is part of the U.S. National Science Foundation's UV Monitoring Network. Here we present a UV climatology for Palmer Station based on the recently produced "Version 2" data edition. This data set will supersede the original release "Version 0". Corrections applied to the new version increased biologically effective UV dose rates by 0-9%. Values of UV-A irradiance changed by -8% to +10%. A comparison with results of a radiative transfer model confirmed that measurements of different years are consistent to within +/-5%. Total ozone column was calculated from UV spectra and was found to agree with measurements of NASA's Total Ozone Mapping Spectrometer (TOMS) installed on the Nimbus-7 satellite to within 1%. TOMS measurements on the Earth Probe satellite are 3% lower than SUV-100 data. Effective surface albedo was estimated from clear sky spectra. Between August and November, albedo typically ranges between 0.6 and 0.95. After melting of snow and sea ice, albedo varies between 0.3 and 0.5. Biologically effective UV radiation is largest in November and December when low total ozone amounts coincide with relatively small solar zenith angles (SZA). During these months, the noon-time UV Index typically varies between 4 and 7, but UV indices as high as 14.8 have been observed. The largest erythemal daily dose of 8.8 kJ/m2 was measured on 11/10/97 and 12/7/98. Linear regression analyses did not indicate statistically significant trends in UV or visible radiation, with the exception of February when small downward trends with statistical significance were observed. On average, clouds reduce UV irradiance at 345 nm between 28% (October and November) and 42% (February) compared to clear sky levels. In extreme cases, reductions by clouds can be as high as 90%. Between September and November, the variability

  17. A total station spatial positioning method based on rotary laser scanning and ultrasonic ranging

    Science.gov (United States)

    Wu, Jun; Zhu, Jigui; Yu, Zhijing; Zhuge, Jingchang; Xue, Bin

    2016-11-01

    Total station spatial coordinator measuring technology is extensively applied in the large-scale measurement of industrial assembly and manufacturing for its flexibility and adaptability. The existing total station technology has some principal limits such as poor efficiency and single tasking; in order to achieve the total station spatial coordinator measuring technology with the advantages of multi-task, real-time measurement, and high accuracy, this paper presents a novel total station measurement method by using multi-laser plane constraints established through rotating planar planes and distance information obtained with an ultrasonic ranging method. With the spatial divergence angles of the optoelectronic scanning and ultrasonic arrays, this method can measure the spatial coordinates in multi-task and real-time with a single station and a portable target bar. Experimental results show that the proposed method is feasible and valid with satisfactory accuracy. The maximum distance measurement error is less than 0.2 mm in a volume that is 5 m far away from the station.

  18. A subcarrier-pair based resource allocation scheme using proportional fairness for cooperative OFDM-based cognitive radio networks.

    Science.gov (United States)

    Ma, Yongtao; Zhou, Liuji; Liu, Kaihua

    2013-08-09

    The paper presents a joint subcarrier-pair based resource allocation algorithm in order to improve the efficiency and fairness of cooperative multiuser orthogonal frequency division multiplexing (MU-OFDM) cognitive radio (CR) systems. A communication model where one source node communicates with one destination node assisted by one half-duplex decode-and-forward (DF) relay is considered in the paper. An interference-limited environment is considered, with the constraint of transmitted sum-power over all channels and aggregate average interference towards multiple primary users (PUs). The proposed resource allocation algorithm is capable of maximizing both the system transmission efficiency and fairness among secondary users (SUs). Besides, the proposed algorithm can also keep the interference introduced to the PU bands below a threshold. A proportional fairness constraint is used to assure that each SU can achieve a required data rate, with quality of service guarantees. Moreover, we extend the analysis to the scenario where each cooperative SU has no channel state information (CSI) about non-adjacent links. We analyzed the throughput and fairness tradeoff in CR system. A detailed analysis of the performance of the proposed algorithm is presented with the simulation results.

  19. NIRS-based hyperscanning reveals inter-brain neural synchronization during cooperative Jenga game with face-to-face communication

    Directory of Open Access Journals (Sweden)

    Ning eLiu

    2016-03-01

    Full Text Available Functional near-infrared spectroscopy (fNIRS is an increasingly popular technology for studying social cognition. In particular, fNIRS permits simultaneous measurement of hemodynamic activity in two or more individuals interacting in a naturalistic setting. Here, we used fNIRS hyperscanning to study social cognition and communication in human dyads engaged in cooperative and non-cooperative interaction while they played the game of Jenga™. Novel methods were developed to identify synchronized channels for each dyad and a structural node-based spatial registration approach was utilized for inter-dyad analyses. Strong inter-brain neural synchrony (INS was observed in the posterior region of the right middle and superior frontal gyrus, in particular Brodmann area 8, during cooperative and obstructive interaction. This synchrony was not observed during the parallel game play condition and the dialogue section, suggesting that BA8 was involved in goal-oriented social interaction such as complex interactive movements and social decision-making. INS was also observed in the dorsomedial prefrontal region (dmPFC, in particular Brodmann 9, during cooperative interaction only. These additional findings suggest that BA9 may be particularly engaged when theory-of-mind is required for cooperative social interaction. The new methods described here have the potential to significantly extend fNIRS applications to social cognitive research.

  20. Agent Virus of Cooperation (Avicoop: an Intelligent Model of Cooperation and Collaboration Based on the MAS for Data Exchange in Ad hoc Network

    Directory of Open Access Journals (Sweden)

    Claude Tangha

    2012-09-01

    Full Text Available We propose in this paper a response to the problem of cooperation and collaboration between nodes in a mobile ad hoc network (MANET for intelligent data relays from one source to a destination. In their operation, each routing protocol relies on the support of each node for end-to-end messages routing by completely ignoring the autonomous nature of the node that is to be free to accept, reject, relay or otherwise simply manipulate the protocols principle. This random and unpredictable behavior of the node impacts on the routing effectiveness in the global network. Our approach is based on multi-agent systems (MAS and game theory, especially the iterated version of the Prisoner's Dilemma. The proposed model is validated by a prototype.

  1. Comparative Analysis and Cultivation of New Agricultural Business Entities Based on Comparison of Family Farms and Professional Cooperatives

    OpenAIRE

    Yang, Fang; LIU, Xingxi; Zhang, Yingliang

    2014-01-01

    Cultivating new bussiness entities is the key to speeding up improving new agricultural production and operating system. This study discussed two representative entities under the agricultural production and operating system based on household contract management, namely, family farms and cooperatives. It introduced current development status of these two entities in Chongqing region, and discussed prominent problems of understanding, management, fund, personnel, technology, information, and ...

  2. GeoScape: An Instructional Rock Garden for Inquiry-Based Cooperative Learning Exercises in Introductory Geology Courses.

    Science.gov (United States)

    Calderone, Gary J.; Thompson, J. Robert; Johnson, Wayne M.; Kadel, Steve D.; Nelson, Pamela J.; Hall-Wallace, Michelle; Butler, Robert F.

    2003-01-01

    GeoScape is a landscape design consisting of colored gravel, strategically placed flagstone and boulders, and two vertical features that simulate the geology of fictitious regions. Employs "hands-on", inquiry-based, and cooperative learning techniques to help students develop problem solving and critical thinking skills. Explains the construction,…

  3. Constructing Knowledge with an Agent-Based Instructional Program: A Comparison of Cooperative and Individual Meaning Making

    Science.gov (United States)

    Moreno, Roxana

    2009-01-01

    Participants in the present study were 87 college students who learned about botany using an agent-based instructional program with three different learning approaches: individual, jigsaw, or cooperative learning. Results showed no differences among learning approaches on retention. Students in jigsaw groups reported higher cognitive load during…

  4. Alkaloid-Derived Thioureas in Asymmetric Organocatalysis: A Cooperative Learning Activity in a Project-Based Laboratory Course

    Science.gov (United States)

    Monge, David

    2015-01-01

    An experiment carried out by advanced undergraduate students in a project-based laboratory course is described. Taking into account the positive effects of working in teams, which has been key for successful research in industry and academia, a cooperative learning experience in the laboratory was developed. Students working in teams of four…

  5. DEADS: Depth and Energy Aware Dominating Set Based Algorithm for Cooperative Routing along with Sink Mobility in Underwater WSNs

    Directory of Open Access Journals (Sweden)

    Amara Umar

    2015-06-01

    Full Text Available Performance enhancement of Underwater Wireless Sensor Networks (UWSNs in terms of throughput maximization, energy conservation and Bit Error Rate (BER minimization is a potential research area. However, limited available bandwidth, high propagation delay, highly dynamic network topology, and high error probability leads to performance degradation in these networks. In this regard, many cooperative communication protocols have been developed that either investigate the physical layer or the Medium Access Control (MAC layer, however, the network layer is still unexplored. More specifically, cooperative routing has not yet been jointly considered with sink mobility. Therefore, this paper aims to enhance the network reliability and efficiency via dominating set based cooperative routing and sink mobility. The proposed work is validated via simulations which show relatively improved performance of our proposed work in terms the selected performance metrics.

  6. Merged dust climatology in Phoenix, Arizona based on satellite and station data

    Science.gov (United States)

    Lei, Hang; Wang, Julian X. L.; Tong, Daniel Q.; Lee, Pius

    2016-11-01

    In order to construct climate quality long-term dust storm dataset, merged dust storm climatology in Phoenix is developed based on three data sources: regular meteorological records, in situ air quality measurements, and satellite remote sensing observations. The result presented in this paper takes into account the advantages of each dataset and integrates individual analyses demonstrated and presented in previous studies that laid foundation to reconstruct a consistent and continuous time series of dust frequency. A key for the merging procedure is to determine analysis criteria suitable for each individual data source. A practical application to historic records of dust storm activities over the Phoenix area is presented to illustrate detailed steps, advantages, and limitations of the newly developed process. Three datasets are meteorological records from the Sky Harbor station, satellite observed aerosol optical depth data from moderate resolution imaging spectroradiometer, and the U.S. Environmental Protection Agency Air Quality System particulate matter data of eight sites surrounding Phoenix. Our purpose is to construct dust climatology over the Phoenix region for the period 1948-2012. Data qualities of the reconstructed dust climatology are assessed based on the availability and quality of the input data. The period during 2000-2012 has the best quality since all datasets are well archived. The reconstructed climatology shows that dust storm activities over the Phoenix region have large interannual variability. However, seasonal variations show a skewed distribution with higher frequency of dust storm activities in July and August and relatively quiet during the rest of months. Combining advantages of all the available datasets, this study presents a merged product that provides a consistent and continuous time series of dust storm activities suitable for climate studies.

  7. Base Station Placement Algorithm for Large-Scale LTE Heterogeneous Networks.

    Science.gov (United States)

    Lee, Seungseob; Lee, SuKyoung; Kim, Kyungsoo; Kim, Yoon Hyuk

    2015-01-01

    Data traffic demands in cellular networks today are increasing at an exponential rate, giving rise to the development of heterogeneous networks (HetNets), in which small cells complement traditional macro cells by extending coverage to indoor areas. However, the deployment of small cells as parts of HetNets creates a key challenge for operators' careful network planning. In particular, massive and unplanned deployment of base stations can cause high interference, resulting in highly degrading network performance. Although different mathematical modeling and optimization methods have been used to approach various problems related to this issue, most traditional network planning models are ill-equipped to deal with HetNet-specific characteristics due to their focus on classical cellular network designs. Furthermore, increased wireless data demands have driven mobile operators to roll out large-scale networks of small long term evolution (LTE) cells. Therefore, in this paper, we aim to derive an optimum network planning algorithm for large-scale LTE HetNets. Recently, attempts have been made to apply evolutionary algorithms (EAs) to the field of radio network planning, since they are characterized as global optimization methods. Yet, EA performance often deteriorates rapidly with the growth of search space dimensionality. To overcome this limitation when designing optimum network deployments for large-scale LTE HetNets, we attempt to decompose the problem and tackle its subcomponents individually. Particularly noting that some HetNet cells have strong correlations due to inter-cell interference, we propose a correlation grouping approach in which cells are grouped together according to their mutual interference. Both the simulation and analytical results indicate that the proposed solution outperforms the random-grouping based EA as well as an EA that detects interacting variables by monitoring the changes in the objective function algorithm in terms of system

  8. Compliance boundaries for multiple-frequency base station antennas in three directions.

    Science.gov (United States)

    Thielens, Arno; Vermeeren, Günter; Kurup, Divya; Joseph, Wout; Martens, Luc

    2013-09-01

    In this article, compliance boundaries and allowed output powers are determined for the front, back, and side of multiple-frequency base station antennas, based on the root-mean-squared electric field, the whole-body averaged specific absorption rate (SAR), and the 10 g averaged SAR in both the limbs and the head and trunk. For this purpose, the basic restrictions and reference levels defined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) for both the general public and occupational exposure are used. The antennas are designed for Global System for Mobile Communications around 900 MHz (GSM900), GSM1800, High Speed Packet Access (HSPA), and Long Term Evolution (LTE), and are operated with output powers at the individual frequencies up to 300 W. The compliance boundaries are estimated using finite-difference time-domain simulations with the Virtual Family Male and have been determined for three directions with respect to the antennas for 800, 900, 1800, and 2600 MHz. The reference levels are not always conservative when the radiating part of the antenna is small compared to the length of the body. Combined compliance distances, which ensure compliance with all reference levels and basic restrictions, have also been determined for each frequency. A method to determine a conservative estimation of compliance boundaries for multiple-frequency (cumulative) exposure is introduced. Using the errors on the estimated allowed powers, an uncertainty analysis is carried out for the compliance distances. Uncertainties on the compliance distances are found to be smaller than 122%.

  9. 基于簇间干扰消除的静态基站协作策略%A static base station coordination strategy based on inter-cluster interference cancellation

    Institute of Scientific and Technical Information of China (English)

    孙丽楠; 张中兆; 沙学军; 蒋样琳

    2011-01-01

    在分析了上行链路静态分簇基站协作策略及动态分簇基站协作策略的基础上,提出了一种基于簇间干扰消除的静态基站协作策略.运用此策略时,协作基站采用线性波束成型或连续干扰消除技术,对邻簇的边缘用户进行干扰抑制,有效地消除簇间干扰;对簇内用户采用线性波束成型,抑制簇内多用户间的干扰.仿真表明,此策略性能优于单小区处理策略和静态分簇策略,在某些情况下甚至超出动态分簇策略,有效地消除了小区间干扰,改善了用户公平性,提高了频谱效率,同时减少了动态分簇策略所需的算法复杂度.%After analyzing the static clustering-based base station coordination strategy and the dynamic clustering-based base station coordination strategy for the uplink, this paper proposes a static base station coordination strategy based on inter-cluster interference cancellation. When the new strategy works, coordinated base stations use the linear beam forming or the successive interference cancellation technique to suppress the interference from the edge users in adjacent clusters to effectively eliminate the inter-cluster interference, and to intra-cluster users, adopt the linear beam forming to cooperatively suppress the intra-cluster multi-user interference. The simulations show that the proposed strategy outperforms the single-cell processing strategy and the static clustering strategy, and in some cases, is even better than the dynamic clustering strategy, achieving the effective elimination of inter-cell interference and the improvement of the user fairness and the spectral efficiency. Moreover, it reduces the algorithm complexity needed by the dynamic clustering strategy.

  10. Design and implementation of a project-based active/cooperative engineering design course for freshmen

    Science.gov (United States)

    Abdulaal, R. M.; Al-Bahi, A. M.; Soliman, A. Y.; Iskanderani, F. I.

    2011-08-01

    A project-based active/cooperative design course is planned, implemented, assessed and evaluated to achieve several desired engineering outcomes. The course allows freshman-level students to gain professional hands-on engineering design experience through an opportunity to practise teamwork, quality principles, communication skills, life-long learning, realistic constraints and awareness of current domestic and global challenges. Throughout successive design reports and in-class assignments, the students are required by the end of the semester to communicate, clearly and concisely, the details of their design both orally and in writing through a functional artefact/prototype, a design notebook, an A0 project poster and a final oral presentation. In addition to these direct assessment tools, several indirect measures are used to ensure triangulation. Assignments are based on customer expectations using a detailed checklist. This paper shows the direct and indirect assessment tools that indicated a high level of achievement of course learning outcomes and a high level of student satisfaction.

  11. Cooperative Planning for UAS-based Sensor Networks In Realistic Communication Environments

    Science.gov (United States)

    Stachura, M.

    This dissertation develops a unified, tractable algorithm for distributed planning for multiple unmanned aircraft based sensor networks with performance bounds. An information-theoretic objective function is derived that incorporates sensing and communication to guide a cooperative team of unmanned aircraft. The communication is modelled with packet erasure channels for each link in a multi-hop mesh network. This objective is shown to be intractable and assumptions are made to find a tractable formulation. This tractable formulation is then distributed using the chain rule of mutual information and optimization algorithms are designed with performance bounds for different scenarios and compared against the fully centralized mutual information approach. This comparison is done analytically using submodularity under certain assumptions and Monte Carlo simulations to evaluate the algorithms when these assumptions break down. A novel unmanned aircraft system platform was developed to facilitate experiments with multiple unmanned aircraft utilizing sensing and multi-hop mesh networking. This system was used to perform localization experiments of radio frequency emitters based on the received signal strength measurement. The planning algorithms were demonstrated with multiple aircraft to show there validity and tractability on a real world scenario. These experiments were used to asses the algorithms performance showing the improvement in sensing is appreciable and specifically the benefits of utilizing multi-hop communication.

  12. Sustainability of Water Resources in the Upstream Watershed- Based Community Engagement and Multistakeholder Cooperation

    Science.gov (United States)

    Brotosusilo, Agus; Utari, Dyah; Agung Satria, Afrizal

    2016-02-01

    The communities engagement become the backbone of the conservation in the Citanduy upstream watershed. It functioning as a major deal and the first one in keeping his own Watershed. This paper based on Community Engagement Grants (CEGs). Program Society-based empowerment approach is also emphasized in the viewpoint of environmental law that is useful to set governance and sanctions in watershed management. The type of activity to be undertaken are the expansion of awareness programs communities of the existence and condition of the watershed Citanduy, the formation of a cadre of conservationists environment that is primarily directed to children and women, the institutionalization of customary law environment, and afforestation by planting 100,000 prolific trees, tree conservationists, and Sunda endemic tree in the land surrounding the watershed upstream Citanduy. The Program involves several partners and stakeholders who helped in substance and operational support activities in the field.. Result of program shows that Community Engagement Grants need cooperation among stakeholders by positioning the community as main subject of changing, not as subject who does not understand their needs to change.

  13. Ingroup favoritism and intergroup cooperation under indirect reciprocity based on group reputation.

    Science.gov (United States)

    Masuda, Naoki

    2012-10-21

    Indirect reciprocity in which players cooperate with unacquainted other players having good reputations is a mechanism for cooperation in relatively large populations subjected to social dilemma situations. When the population has group structure, as is often found in social networks, players in experiments are considered to show behavior that deviates from existing theoretical models of indirect reciprocity. First, players often show ingroup favoritism (i.e., cooperation only within the group) rather than full cooperation (i.e., cooperation within and across groups), even though the latter is Pareto efficient. Second, in general, humans approximate outgroup members' personal characteristics, presumably including the reputation used for indirect reciprocity, by a single value attached to the group. Humans use such a stereotypic approximation, a phenomenon known as outgroup homogeneity in social psychology. I propose a model of indirect reciprocity in populations with group structure to examine the possibility of ingroup favoritism and full cooperation. In accordance with outgroup homogeneity, I assume that players approximate outgroup members' personal reputations by a single reputation value attached to the group. I show that ingroup favoritism and full cooperation are stable under different social norms (i.e., rules for assigning reputations) such that they do not coexist in a single model. If players are forced to consistently use the same social norm for assessing different types of interactions (i.e., ingroup versus outgroup interactions), only full cooperation survives. The discovered mechanism is distinct from any form of group selection. The results also suggest potential methods for reducing ingroup bias to shift the equilibrium from ingroup favoritism to full cooperation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Cooperative Handover Management in Dense Cellular Networks

    KAUST Repository

    Arshad, Rabe

    2017-02-07

    Network densification has always been an important factor to cope with the ever increasing capacity demand. Deploying more base stations (BSs) improves the spatial frequency utilization, which increases the network capacity. However, such improvement comes at the expense of shrinking the BSs\\' footprints, which increases the handover (HO) rate and may diminish the foreseen capacity gains. In this paper, we propose a cooperative HO management scheme to mitigate the HO effect on throughput gains achieved via cellular network densification. The proposed HO scheme relies on skipping HO to the nearest BS at some instances along the user\\'s trajectory while enabling cooperative BS service during HO execution at other instances. To this end, we develop a mathematical model, via stochastic geometry, to quantify the performance of the proposed HO scheme in terms of coverage probability and user throughput. The results show that the proposed cooperative HO scheme outperforms the always best connected based association at high mobility. Also, the value of BS cooperation along with handover skipping is quantified with respect to the HO skipping only that has recently appeared in the literature. Particularly, the proposed cooperative HO scheme shows throughput gains of 12% to 27% and 17% on average, when compared to the always best connected and HO skipping only schemes at user velocity ranging from 80 km/h to 160 Km/h, respectively.

  15. Analysis of Base Station Assisted Novel Network Design Space for Edge-based WSNs

    Directory of Open Access Journals (Sweden)

    Muni Venkateswarlu K.

    2015-06-01

    Full Text Available Limited and constrained energy resources of wireless sensor network should be used wisely to prolong sensor nodes lifetime. To achieve high energy efficiency and to increase wireless sensor network lifetime, sensor nodes are grouped together to form clusters. Organizing wireless sensor networks into clusters enables the efficient utilization of limited energy resources of the deployed sensor nodes. However, the problems of unbalanced energy consumption exist in intra and inter cluster communication, and it is tightly bound to the role and the location of a sensor nodes and cluster heads in the network. Also, clustering mechanism results in an unequal load distribution in the network. This paper presents an analytical and conceptual model of Energy-efficient edge-based network partitioning scheme proposed for wireless sensor networks. Also, it analyzes different network design space proposed for wireless sensor networks and evaluates their performance. From the experimental results it is observed that, with proper network organization mechanism, sensor network resources are utilized effectively to elevate network lifetime.

  16. Research on image fusion of missile team based on multi-agent cooperative blackboard model

    Science.gov (United States)

    Sen, Guo; Munan, Li

    The target of cooperative engagement of missile teams is to furthest improve hit rate of target according to communication and cooperation among missiles. In this paper the problems of image fusion between missile teams in complex combat environment was analyzed, after which an muti-agent blackboard cooperative model was presented and a public information platform of missile team is built according to this model. Through these, the fusion of images taken from muti-sensor of missiles can be realized and the hit rate of attacking target will be improved. At last, an simulation experiment were performed, and the feasibility of the method is proved by simulation experiment.

  17. Vertical profiling of atmospheric refractivity using GPS STD data from a single ground-based station: Simulations and applications

    Science.gov (United States)

    Zus, F.; Dick, G.; Heise, S.; Wickert, J.; Ramatschi, M.

    2013-12-01

    We developed a ray-tracing operator to compute the signal travel time delay due to the neutral atmosphere, known as Slant Total Delay (STD), between a GPS satellite and a ground-based receiving station. Having developed a rapid and precise forward operator we constructed the tangent-linear (adjoint) operator to estimate refractivity in the vicinity of a single station. The refractivity retrievals potentially complement refractivity retrievals from radio occultation data and can be considered a valuable input for Numerical Weather Prediction. In a first experiment (simulation) we study the feasibility for vertical profiling of refractivity using STDs from a single station. The simulation cycle consists of the computation of STDs given a refractivity profile, the addition of noise to mimic observation errors and the retrieval of a refractivity profile from the artificial STDs by a non-linear least-square analysis. Clearly, besides the noise level, the elevation range plays an important role regarding the quality of the refractivity retrieval; near-horizon STDs corrupted by noise allow a significantly better refractivity retrieval than STDs close to the zenith without any noise. The simulation study suggests that near-horizon STDs provide additional information when compared to Zenith Total Delays (ZTDs). In a second experiment (application) we replace the artificial STDs in the simulation by STDs retrieved from GPS phase-observations. The procedure is repeated station-by-station for 200 stations in Germany. We do not find a significant benefit from STDs over ZTDs in the retrieved refractivity profile since near-horizon STDs are rarely available and representative errors due to asymmetry are non-negligable. We attempt to mitigate the latter problem by the additional estimation of horizontal gradients, and indeed, we find strong evidence that STDs retrieved from GPS phase-observations contain asymmetric information. The former problem still poses a serious limitation

  18. Hybrid information retrieval policies based on cooperative cache in mobile P2P networks

    Institute of Scientific and Technical Information of China (English)

    Quanqing XU; Hengtao SHEN; Zaiben CHEN; Bin CUI; Xiaofang ZHOU; Yafei DAI

    2009-01-01

    The concept of Peer-to-Peer (P2P) has been in-troduced into mobile networks, which has led to the emer-gence of mobile P2P networks, and originated potential ap-plications in many fields. However, mobile P2P networks are subject to the limitations of transmission range, and highly dynamic and unpredictable network topology, giving rise to many new challenges for efficient information retrieval. In this paper, we propose an automatic and economical hybrid information retrieval approach based on cooperative cache. In this method, the region covered by a mobile P2P network is partitioned into subregions, each of which is identified by a unique ID and known to all peers. All the subregions then constitute a mobile Kademlia (MKad) network. The pro-posed hybrid retrieval approach aims to utilize the flooding-based and Distributed Hash Table (DHT)-based schemes in MKad for indexing and searching according to the designed utility functions. To further facilitate information retrieval, we present an effective cache update method by considering all relevant factors. At the same time, the combination of two different methods for cache update is also introduced. One of them is pull based on time stamp including two different pulls: an on-demand pull and a periodical pull, and the other is a push strategy using update records. Furthermore, we provide detailed mathematical analysis on the cache hit ratio of our approach. Simulation experiments in NS-2 showed that the proposed approach is more accurate and efficient than the existing methods.

  19. Space Station Freedom (SSF) Data Management System (DMS) performance model data base

    Science.gov (United States)

    Stovall, John R.

    1993-01-01

    The purpose of this document was originally to be a working document summarizing Space Station Freedom (SSF) Data Management System (DMS) hardware and software design, configuration, performance and estimated loading data from a myriad of source documents such that the parameters provided could be used to build a dynamic performance model of the DMS. The document is published at this time as a close-out of the DMS performance modeling effort resulting from the Clinton Administration mandated Space Station Redesign. The DMS as documented in this report is no longer a part of the redesigned Space Station. The performance modeling effort was a joint undertaking between the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Flight Data Systems Division (FDSD) and the NASA Ames Research Center (ARC) Spacecraft Data Systems Research Branch. The scope of this document is limited to the DMS core network through the Man Tended Configuration (MTC) as it existed prior to the 1993 Clinton Administration mandated Space Station Redesign. Data is provided for the Standard Data Processors (SDP's), Multiplexer/Demultiplexers (MDM's) and Mass Storage Units (MSU's). Planned future releases would have added the additional hardware and software descriptions needed to describe the complete DMS. Performance and loading data through the Permanent Manned Configuration (PMC) was to have been included as it became available. No future releases of this document are presently planned pending completion of the present Space Station Redesign activities and task reassessment.

  20. A geomorphology-based ANFIS model for multi-station modeling of rainfall-runoff process

    Science.gov (United States)

    Nourani, Vahid; Komasi, Mehdi

    2013-05-01

    This paper demonstrates the potential use of Artificial Intelligence (AI) techniques for predicting daily runoff at multiple gauging stations. Uncertainty and complexity of the rainfall-runoff process due to its variability in space and time in one hand and lack of historical data on the other hand, cause difficulties in the spatiotemporal modeling of the process. In this paper, an Integrated Geomorphological Adaptive Neuro-Fuzzy Inference System (IGANFIS) model conjugated with C-means clustering algorithm was used for rainfall-runoff modeling at multiple stations of the Eel River watershed, California. The proposed model could be used for predicting runoff in the stations with lack of data or any sub-basin within the watershed because of employing the spatial and temporal variables of the sub-basins as the model inputs. This ability of the integrated model for spatiotemporal modeling of the process was examined through the cross validation technique for a station. In this way, different ANFIS structures were trained using Sugeno algorithm in order to estimate daily discharge values at different stations. In order to improve the model efficiency, the input data were then classified into some clusters by the means of fuzzy C-means (FCMs) method. The goodness-of-fit measures support the gainful use of the IGANFIS and FCM methods in spatiotemporal modeling of hydrological processes.