WorldWideScience

Sample records for wireless lan environment

  1. Proposal of a simplified intra-school wireless LAN environment for spreading the ICT utilization in education

    OpenAIRE

    佐藤, 亮一; 矢嶋, 俊樹; 下保, 敏和; 岸本, 功; 興治, 文子; 鈴木, 賢治; Sato, Ryoichi; Yajima, Toshiki; Kaho, Toshikazu; Kishimoto, Isao; Okiharu, Fumiko; Suzuki, Kenji

    2015-01-01

    This paper proposes a simple solution for a teacher to easily construct intra-school wireless LAN (WLAN) environment in an ordinary classroom. No special knowledge on ICT and the related technologies is required in the construction procedure. The teacher only connects some cables between the prepared three components as 1) access point, 2) LCD projector, and 3) HDMI screen projection device. These devices are all low-priced. It also takes about 3 to 4 minutes to complete the WLAN environment....

  2. Applications of medical wireless LAN systems (MedLAN)

    OpenAIRE

    Banitsas, KA; Istepanian, RSH; Tachakra, S

    2002-01-01

    This is a post-peer-review, pre-copyedit version of an article published in Journal of Medical Marketing. The definitive publisher-authenticated version "Konstantinos A. Banitsas, R.S.H. Istepanian, Sapal Tachakra. Applications of medical Wireless LAN systems (MedLAN). Journal of Medical Marketing, Volume 2, Number 2, 1 January 2002 , pp. 136-142(7)" is available online at: http://www.ingentaconnect.com/content/pal/jomm/2002/00000002/00000002/art00008. In this paper the Wireless LAN (WLAN)...

  3. Patient monitoring using infrastructure-oriented wireless LANs.

    Science.gov (United States)

    Varshney, Upkar

    2006-01-01

    There is considerable interest in using wireless and mobile technologies in patient monitoring in diverse environments including hospitals and nursing homes. However, there has not been much work in determining the requirements of patient monitoring and satisfying these requirements using infrastructure-oriented wireless networks. In this paper, we derive several requirements of patient monitoring and show how infrastructure-oriented wireless LANs, such as versions of IEEE 802.11, can be used to support patient monitoring in diverse environments.

  4. Proposal of Wireless Traffic Control Schemes for Wireless LANs

    Science.gov (United States)

    Hiraguri, Takefumi; Ichikawa, Takeo; Iizuka, Masataka; Kubota, Shuji

    This paper proposes two traffic control schemes to support the communication quality of multimedia streaming services such as VoIP and audio/video over IEEE 802.11 wireless LAN systems. The main features of the proposed scheme are bandwidth control for each flow of the multimedia streaming service and load balancing between access points (APs) of the wireless LAN by using information of data link, network and transport layers. The proposed schemes are implemented on a Linux machine which is called the wireless traffic controller (WTC). The WTC connects a high capacity backbone network and an access network to which the APs are attached. We evaluated the performance of the proposed WTC and confirmed that the communication quality of the multimedia streaming would be greatly improved by using this technique.

  5. Sniffer Channel Selection for Monitoring Wireless LANs

    Science.gov (United States)

    Song, Yuan; Chen, Xian; Kim, Yoo-Ah; Wang, Bing; Chen, Guanling

    Wireless sniffers are often used to monitor APs in wireless LANs (WLANs) for network management, fault detection, traffic characterization, and optimizing deployment. It is cost effective to deploy single-radio sniffers that can monitor multiple nearby APs. However, since nearby APs often operate on orthogonal channels, a sniffer needs to switch among multiple channels to monitor its nearby APs. In this paper, we formulate and solve two optimization problems on sniffer channel selection. Both problems require that each AP be monitored by at least one sniffer. In addition, one optimization problem requires minimizing the maximum number of channels that a sniffer listens to, and the other requires minimizing the total number of channels that the sniffers listen to. We propose a novel LP-relaxation based algorithm, and two simple greedy heuristics for the above two optimization problems. Through simulation, we demonstrate that all the algorithms are effective in achieving their optimization goals, and the LP-based algorithm outperforms the greedy heuristics.

  6. Adjusting DICOM specifications when using wireless LANs: The MedLAN example

    OpenAIRE

    Banitsas, KA; Tachakra, S; Song, YH

    2003-01-01

    Wireless networks will become increasingly useful in point-of-care areas such as hospitals, because of their ease of use and their flexibility. A system called MedLAN has been developed by the Central Middlesex Hospital and Brunei University to take advantage of the above desirable properties of WLANs for use in accident & emergency departments to broadcast live, high quality video images and sound over a LAN or the Internet. However, in many cases, the limited available throughput of such a ...

  7. Wireless LAN security management with location detection capability in hospitals.

    Science.gov (United States)

    Tanaka, K; Atarashi, H; Yamaguchi, I; Watanabe, H; Yamamoto, R; Ohe, K

    2012-01-01

    In medical institutions, unauthorized access points and terminals obstruct the stable operation of a large-scale wireless local area network (LAN) system. By establishing a real-time monitoring method to detect such unauthorized wireless devices, we can improve the efficiency of security management. We detected unauthorized wireless devices by using a centralized wireless LAN system and a location detection system at 370 access points at the University of Tokyo Hospital. By storing the detected radio signal strength and location information in a database, we evaluated the risk level from the detection history. We also evaluated the location detection performance in our hospital ward using Wi-Fi tags. The presence of electric waves outside the hospital and those emitted from portable game machines with wireless communication capability was confirmed from the detection result. The location detection performance showed an error margin of approximately 4 m in detection accuracy and approximately 5% in false detection. Therefore, it was effective to consider the radio signal strength as both an index of likelihood at the detection location and an index for the level of risk. We determined the location of wireless devices with high accuracy by filtering the detection results on the basis of radio signal strength and detection history. Results of this study showed that it would be effective to use the developed location database containing radio signal strength and detection history for security management of wireless LAN systems and more general-purpose location detection applications.

  8. Mining Behavioral Groups in Large Wireless LANs

    OpenAIRE

    Hsu, Wei-jen; Dutta, Debojyoti; Helmy, Ahmed

    2006-01-01

    One vision of future wireless networks is that they will be deeply integrated and embedded in our lives and will involve the use of personalized mobile devices. User behavior in such networks is bound to affect the network performance. It is imperative to study and characterize the fundamental structure of wireless user behavior in order to model, manage, leverage and design efficient mobile networks. It is also important to make such study as realistic as possible, based on extensive measure...

  9. Optimizing wireless LAN for longwall coal mine automation

    Energy Technology Data Exchange (ETDEWEB)

    Hargrave, C.O.; Ralston, J.C.; Hainsworth, D.W. [Exploration & Mining Commonwealth Science & Industrial Research Organisation, Pullenvale, Qld. (Australia)

    2007-01-15

    A significant development in underground longwall coal mining automation has been achieved with the successful implementation of wireless LAN (WLAN) technology for communication on a longwall shearer. WIreless-FIdelity (Wi-Fi) was selected to meet the bandwidth requirements of the underground data network, and several configurations were installed on operating longwalls to evaluate their performance. Although these efforts demonstrated the feasibility of using WLAN technology in longwall operation, it was clear that new research and development was required in order to establish optimal full-face coverage. By undertaking an accurate characterization of the target environment, it has been possible to achieve great improvements in WLAN performance over a nominal Wi-Fi installation. This paper discusses the impact of Fresnel zone obstructions and multipath effects on radio frequency propagation and reports an optimal antenna and system configuration. Many of the lessons learned in the longwall case are immediately applicable to other underground mining operations, particularly wherever there is a high degree of obstruction from mining equipment.

  10. MEDIAN: Wireless broadband LAN for multimedia applications

    NARCIS (Netherlands)

    Vliet, P.J. van

    1998-01-01

    MEDIAN is one of the projects in the mobile domain of the Advanced Communications Technologies and Services (ACTS) programme of the European Commission. The main obiective of the MEDIAN project is to evaluate and implement a high speed Wireless Customer Premises / Local Area Network (WCPN/WLAN)

  11. Rogue AP Detection in the Wireless LAN for Large Scale Deployment

    OpenAIRE

    Sang-Eon Kim; Byung-Soo Chang; Sang Hong Lee; Dae Young Kim

    2006-01-01

    The wireless LAN standard, also known as WiFi, has begun to use commercial purposes. This paper describes access network architecture of wireless LAN for large scale deployment to provide public service. A metro Ethernet and digital subscriber line access network can be used for wireless LAN with access point. In this network architecture, access point plays interface between wireless node and network infrastructure. It is important to maintain access point without any failure and problems to...

  12. Impact of Implementing VPN to Secure Wireless LAN

    OpenAIRE

    H. Bourdoucen; A. Al Naamany; A. Al Kalbani

    2009-01-01

    Many corporations are seriously concerned about security of networks and therefore, their network supervisors are still reluctant to install WLANs. In this regards, the IEEE802.11i standard was developed to address the security problems, even though the mistrust of the wireless LAN technology is still existing. The thought was that the best security solutions could be found in open standards based technologies that can be delivered by Virtual Private Networking (VPN) bein...

  13. Bandwidth Estimation in Wireless Lans for Multimedia Streaming Services

    Directory of Open Access Journals (Sweden)

    Heung Ki Lee

    2007-01-01

    Full Text Available The popularity of multimedia streaming services via wireless networks presents major challenges in the management of network bandwidth. One challenge is to quickly and precisely estimate the available bandwidth for the decision of streaming rates of layered and scalable multimedia services. Previous studies based on wired networks are too burdensome to be applied to multimedia applications in wireless networks. In this paper, a new method, IdleGap, is suggested to estimate the available bandwidth of a wireless LAN based on the information from a low layer in the protocol stack. We use a network simulation tool, NS-2, to evaluate our new method with various ranges of cross-traffic and observation times. Our simulation results show that IdleGap accurately estimates the available bandwidth for all ranges of cross-traffic (100 Kbps ∼ 1 Mbps with a very short observation time of 10 seconds.

  14. Rogue AP Detection in the Wireless LAN for Large Scale Deployment

    Directory of Open Access Journals (Sweden)

    Sang-Eon Kim

    2006-10-01

    Full Text Available The wireless LAN standard, also known as WiFi, has begun to use commercial purposes. This paper describes access network architecture of wireless LAN for large scale deployment to provide public service. A metro Ethernet and digital subscriber line access network can be used for wireless LAN with access point. In this network architecture, access point plays interface between wireless node and network infrastructure. It is important to maintain access point without any failure and problems to public users. This paper proposes definition of rogue access point and classifies based on functional problem to access the Internet. After that, rogue access point detection scheme is described based on classification over the wireless LAN. The rogue access point detector can greatly improve the network availability to network service provider of wireless LAN.

  15. Development of GPS data remote retrieval system using wireless LAN

    Directory of Open Access Journals (Sweden)

    Koichiro Doi

    2012-11-01

    Full Text Available A remote retrieval system, using a wireless LAN, was developed to retrieve dual-frequency GPS data. The system consists of a ground observation unit (comprising a dual-frequency GPS logger and a data transmission unit and a data retrieval unit. In this system, we use the ZigBee communication protocol to transmit control commands (2.4 GHz, 250 Kbps and a wireless LAN communication to transmit GPS data (2.4 GHz, 54 Mbps. Data of every 30 seconds to transmit to the data retrieval unit are re-sampled from 1-second data at 00 UT each day. We conducted three data-transmission tests with the system: (1 a ground data retrieval test, (2 a data retrieval test from the atmosphere of a few hundred meters high using a small unmanned aircraft, and (3 actual GPS-data retrieval tests from a GPS buoy deployed on sea ice at Nisi-no-ura Cove, Syowa Station, Antarctica. In test (1, we successfully received all the data from the ground observation unit when situated at distances of less than 400 m from the data retrieval unit. In test (2, we obtained approximately 24.5 MB of data from the aircraft at heights of less than 250 m. In test (3, we obtained approximately 23.5 MB of data from the GPS buoy within 10 minutes. The proposed system has the advantage of enabling continuous measurements without aborting the measurement at the data retrievals.

  16. The remote transmission test of the GUAM measurement data by the wireless LAN

    International Nuclear Information System (INIS)

    Asano, Takashi; Fujiwara, Shigeo; Takahashi, Saburo; Nemoto, Tadayuki; Sato, Takashi; Kuniyasu, Kazufusa; Hiruta, Kazuhiko

    2008-01-01

    JAEA has developed and demonstrated the Remote Monitoring (RM) technology on the safeguards equipment at the storage area in PFPF to improve the efficiency of the inspection activity. JAEA is considering the expansion of the RM technology to the safeguards equipment in the process area to improve the efficiency of the inspection activity under the integrated safeguards. JAEA considers that the cabling cost and work in the facility will be reduced to apply the wireless LAN to the RM technology. JAEA performed the confirmatory testing of the performance of the Glove box Unattended Assay and Monitoring system (GUAM) and the remote transmission of the GUAM measurement data by the wireless LAN in cooperation with Japan Nuclear Fuel Limited. In this test, JAEA confirmed it's possible to establish the wireless LAN networking in the process area. This paper reports the applicability of the wireless LAN to the RM technology based on the results of the confirmatory testing. (author)

  17. Corrections to "Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs"

    Directory of Open Access Journals (Sweden)

    Choi Woo-Yong

    2010-01-01

    Full Text Available We have found the errors in the throughput formulae presented in our paper "Connectivity-based reliable multicast MAC protocol for IEEE 802.11 wireless LANs". We provide the corrected formulae and numerical results.

  18. Designing an Efficient Retransmission Scheme for Wireless LANs: Theory and Implementation

    OpenAIRE

    Koutsonikolas, Dimitrios; Wang, Chih-Chun; Hu, Y Charlie; Shroff, Ness

    2010-01-01

    Network coding is known to benefit the downlink retransmissions by the AP in a wireless LAN from exploiriting overhearing at the client nodes. However, designing an efficient and practical retransmission scheme remains a challange. We present an (asymptotically) optimal scheme, ECR, for reduing the downlink retransmissions by the AP in a wireless LAN from exploiting overhearing at the client nodes. The design of ECR, consisting of three components: batch-based operations, a systematic pha...

  19. Application of wireless LAN technology to remote monitoring for inspection equipment

    International Nuclear Information System (INIS)

    Ishiyama, Koichi; Kimura, Takashi; Miura, Yasushi; Yamaguchi, Katsuhiro; Kabuki, Toshihide

    2011-01-01

    To support inspections under an Integrated Safeguards regime into Tokai Reprocessing Plant (TRP), the IAEA suggested making use of Remote Monitoring (RM) capabilities to the inspection equipment (surveillance camera and NDA systems) installed in the spent fuel storage area at TRP. Since TRP had no pre-prepared cabling infrastructure for data transmission in the spent fuel storage area, the option of wireless LAN was chosen over the telephone line due to its lower installation costs. Feasibility studies and tests were performed by TRP on communication and particularly on long-term continuous communication using wireless LAN equipment composed of APs (AP: Access Point) and the external antennas for introducing wireless LAN technology to RM. As a result it was recognized that wireless LAN has enough ability to communicate for long periods of time and consequently the IAEA installed the AP and the external antenna to each inspection equipment and the wireless LAN technology was applied for RM. In this paper, the summary of each test and the results are reported. (author)

  20. Installation of wireless LAN system into the SuperKEKB accelerator tunnel

    International Nuclear Information System (INIS)

    Iwasaki, Masako; Satoh, Masanori

    2014-01-01

    We have installed a wireless LAN system of the accelerator control network into the accelerator tunnel for SuperKEKB, which is the upgrade plan of the KEKB B-factory project. The wireless LAN system is used for the construction and maintenance of the accelerator components. The leaky coaxial cable (LCX) antennas are installed into the arc sections of SuperKEKB tunnel, and the collinear antennas are installed into the straight sections and the injector Linac. We have selected the LCX and collinear antennas with good radiation hardness of more than 1 MGy. After the installation, we evaluated the wireless LAN system and obtained the good network speed performance in the whole tunnel area. (author)

  1. Implementation Alternatives for a Flexible Wireless LAN Transceiver

    NARCIS (Netherlands)

    Schiphorst, Roelof; Hoeksema, F.W.; Slump, Cornelis H.

    2004-01-01

    In our software-defined radio project we have implemented two different types of standards, a continuous-phase-modulation (CPM) based standard, Bluetooth, and an OFDM based standard, HiperLAN/2, on a general-purpose processor. First we describe our baseband software-defined radio testbed for the

  2. Ensuring the security and availability of a hospital wireless LAN system.

    Science.gov (United States)

    Hanada, Eisuke; Kudou, Takato; Tsumoto, Shusaku

    2013-01-01

    Wireless technologies as part of the data communication infrastructure of modern hospitals are being rapidly introduced. Even though there are concerns about problems associated with wireless communication security, the demand is remarkably large. Herein we discuss security countermeasures that must be taken and issues concerning availability that must be considered to ensure safe hospital/business use of wireless LAN systems, referring to the procedures introduced at a university hospital. Security countermeasures differ according to their purpose, such as preventing illegal use or ensuring availability, both of which are discussed. The main focus of the availability discussion is on signal reach, electromagnetic noise elimination, and maintaining power supply to the network apparatus. It is our hope that this information will assist others in their efforts to ensure safe implementation of wireless LAN systems, especially in hospitals where they have the potential to greatly improve information sharing and patient safety.

  3. Installation of secure, always available wireless LAN systems as a component of the hospital communication infrastructure.

    Science.gov (United States)

    Hanada, Eisuke; Kudou, Takato; Tsumoto, Shusaku

    2013-06-01

    Wireless technologies as part of the data communication infrastructure of modern hospitals are being rapidly introduced. Even though there are concerns about problems associated with wireless communication security, the demand is remarkably large. In addition, insuring that the network is always available is important. Herein, we discuss security countermeasures and points to insure availability that must be taken to insure safe hospital/business use of wireless LAN systems, referring to the procedures introduced at Shimane University Hospital. Security countermeasures differ according to their purpose, such as for preventing illegal use or insuring availability, both of which are discussed. It is our hope that this information will assist others in their efforts to insure safe implementation of wireless LAN systems, especially in hospitals where they have the potential to greatly improve information sharing and patient safety.

  4. A New Mechanism for Network Monitoring and Shielding in Wireless LAN

    Directory of Open Access Journals (Sweden)

    Jiujun Cheng

    2014-01-01

    Full Text Available Wireless LAN (WLAN technology is developing rapidly with the help of wireless communication technology and social demand. During the development of WLAN, the security is more and more important, and wireless monitoring and shielding are of prime importance for network security. In this paper, we have explored various security issues of IEEE 802.11 based wireless network and analyzed numerous problems in implementing the wireless monitoring and shielding system. We identify the challenges which monitoring and shielding system needs to be aware of, and then provide a feasible mechanism to avoid those challenges. We implemented an actual wireless LAN monitoring and shielding system on Maemo operating system to monitor wireless network data stream efficiently and solve the security problems of mobile users. More importantly, the system analyzes wireless network protocols efficiently and flexibly, reveals rich information of the IEEE 802.11 protocol such as traffic distribution and different IP connections, and graphically displays later. Moreover, the system running results show that the system has the capability to work stably, and accurately and analyze the wireless protocols efficiently.

  5. A low complexity VBLAST OFDM detection algorithm for wireless LAN systems

    NARCIS (Netherlands)

    Wu, Y.; Lei, Zhongding; Sun, Sumei

    2004-01-01

    A low complexity detection algorithm for VBLAST OFDM system is presented. Using the fact that the correlation among neighboring subcarriers is high for wireless LAN channels, this algorithm significantly reduces the complexity of VBLAST OFDM detection. The performance degradation of the proposed

  6. Multi-service traffic profiles to realise and maintain QoS guarantees in wireless LANs

    NARCIS (Netherlands)

    F.J.M. Panken; G.J. Hoekstra (Gerard)

    2009-01-01

    htmlabstractThis paper shows that throughput parameter \\"bits/s\\" does not provide accurate insight in load conditions and/or traffic demands in Wireless LANs (WLANs). A multi-service traffic profile that does provide this insight is therefore defined. The multi-service traffic profile

  7. Radiofrequency exposure from wireless LANs utilizing Wi-Fi technology.

    Science.gov (United States)

    Foster, Kenneth R

    2007-03-01

    This survey measured radiofrequency (RF) fields from wireless local area networks (WLANs) using Wi-Fi technology against a background of RF fields in the environment over the frequency range 75 MHz-3 GHz. A total of 356 measurements were conducted at 55 sites (including private residences, commercial spaces, health care and educational institutions, and other public spaces) in four countries (U.S., France, Germany, Sweden). Measurements were conducted under conditions that would result in the higher end of exposures from such systems. Where possible, measurements were conducted in public spaces as close as practical to the Wi-Fi access points. Additional measurements were conducted at a distance of approximately 1 m from a laptop while it was uploading and downloading large files to the WLAN. This distance was chosen to allow a useful comparison of fields in the far-field of the antenna in the laptop, and give a representative measure of the exposure that a bystander might receive from the laptop. The exposure to the user, particularly if the antenna of the client card were placed against his or her body, would require different measurement techniques beyond the scope of this study. In all cases, the measured Wi-Fi signal levels were very far below international exposure limits (IEEE C95.1-2005 and ICNIRP) and in nearly all cases far below other RF signals in the same environments. An discusses technical aspects of the IEEE 802.11 standard on which WLANs operate that are relevant to determining the levels of RF energy exposure from WLANs. Important limiting factors are the low operating power of client cards and access points, and the low duty cycle of transmission that normally characterizes their operation.

  8. Enhancing MAC performance of DCF protocol for IEEE 802.11 wireless LANs

    Science.gov (United States)

    Choi, Woo-Yong

    2017-01-01

    The DCF (Distributed Coordination Function) is the basic MAC (Medium Access Control) protocol of IEEE 802.11 wireless LANs and compatible with various IEEE 802.11 PHY extensions. The performance of the DCF degrades exponentially as the number of nodes participating in the DCF transmission procedure increases. To deal with this problem, we propose a simple, however efficient modification of the DCF by which the performance of the DCF is greatly enhanced.

  9. Exposure of the general public due to wireless LAN applications in public places

    International Nuclear Information System (INIS)

    Schmid, G.; Preiner, P.; Lager, D.; Ueberbacher, R.; Georg, R.

    2007-01-01

    The typical exposure caused by wireless LAN applications in public areas has been investigated in a variety of scenarios. Small-sized (internet cafe) and large-scale (airport) indoor scenarios as well as outdoor scenarios in the environment of access points (AP) supplying for residential areas and public places were considered. The exposure assessment was carried out by numerical GTD/UTD computations based on optical wave propagation, as well as by verifying frequency selective measurements in the considered scenarios under real life conditions. In the small-sized indoor scenario the maximum temporal peak values of power density, spatially averaged over body dimensions, were found to be lower than 20 mW/m 2 , corresponding to 0.2% of the reference level according to the European Council Recommendation 1999/519/EC. Local peak values of power density might be 1-2 orders of magnitude higher, spatial and time-averaged values for usual data traffic conditions might be 2-3 orders of magnitude lower, depending on the actual data traffic. In the considered outdoor scenarios, exposure was several orders of magnitude lower than in indoor scenarios due to the usually larger distances to the AP antennas. (authors)

  10. Planning and Optimization of Wireless LANs through Field Measurements

    OpenAIRE

    Mongia, Puneet Kumar; Singh, B. J.

    2013-01-01

    In this paper, the field measurements of signal strength taken at the frequency of 2432 MHz in indoor & outdoor environments are presented and analyzed. The received signal levels from the base station were monitored manually. Total coverage area considered for the measurement campaign consisted of a mixture of different propagation environments. Based on the experimental data obtained, path loss exponent and standard deviation of signal strength variability are derived. It is shown that the ...

  11. QoS Support Polling Scheme for Multimedia Traffic in Wireless LAN MAC Protocol

    Institute of Scientific and Technical Information of China (English)

    YANG Zhijun; ZHAO Dongfeng

    2008-01-01

    Quality of service (QoS) support is a key attribute for multimedia traffic including video, voice, and data in wireless local area networks (LANs) but is limited in 802.11-based wireless LANs. A polling-based scheme called the point coordination function (PCF) was developed for 802.11 LANs to support the trans-mission of multimedia traffic. However, the PCF is not able to meet the desired practical traffic differentiation requirements for real-time data. This paper describes a QoS support polling scheme based on the IEEE 802.11 medium access control (MAC) protocol. The scheme uses a two-level polling mechanism with the QoS classes differentiated by two different access policies. Stations with higher priority traffic such as key or real-time data form the first level and can access the common channel through an exhaustive access policy. Other stations with lower priority traffic form the second level and can access the channel through a gated access policy. A system model based on imbedded Markov chain theory and a generation function were setup to explicitly analyze the mean information packet waiting time of the two-level polling scheme. Theo-retical and simulation results show that the new scheme efficiently differentiates services to guarantee better QoS and system stability.

  12. Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs

    Directory of Open Access Journals (Sweden)

    Woo-Yong Choi

    2009-01-01

    Full Text Available We propose the efficient reliable multicast MAC protocol based on the connectivity information among the recipients. Enhancing the BMMM (Batch Mode Multicast MAC protocol, the reliable multicast MAC protocol significantly reduces the RAK (Request for ACK frame transmissions in a reasonable computational time and enhances the MAC performance. By the analytical performance analysis, the throughputs of the BMMM protocol and our proposed MAC protocol are derived. Numerical examples show that our proposed MAC protocol increases the reliable multicast MAC performance for IEEE 802.11 wireless LANs.

  13. Optimal Modeling of Wireless LANs: A Decision-Making Multiobjective Approach

    Directory of Open Access Journals (Sweden)

    Tomás de Jesús Mateo Sanguino

    2018-01-01

    Full Text Available Communication infrastructure planning is a critical design task that typically requires handling complex concepts on networking aimed at optimizing performance and resources, thus demanding high analytical and problem-solving skills to engineers. To reduce this gap, this paper describes an optimization algorithm—based on evolutionary strategy—created as an aid for decision-making prior to the real deployment of wireless LANs. The developed algorithm allows automating the design process, traditionally handmade by network technicians, in order to save time and cost by improving the WLAN arrangement. To this end, we implemented a multiobjective genetic algorithm (MOGA with the purpose of meeting two simultaneous design objectives, namely, to minimize the number of APs while maximizing the coverage signal over a whole planning area. Such approach provides efficient and scalable solutions closer to the best network design, so that we integrated the developed algorithm into an engineering tool with the goal of modelling the behavior of WLANs in ICT infrastructures. Called WiFiSim, it allows the investigation of various complex issues concerning the design of IEEE 802.11-based WLANs, thereby facilitating design of the study and design and optimal deployment of wireless LANs through complete modelling software. As a result, we comparatively evaluated three target applications considering small, medium, and large scenarios with a previous approach developed, a monoobjective genetic algorithm.

  14. Dynamic Contention Window Control Scheme in IEEE 802.11e EDCA-Based Wireless LANs

    Science.gov (United States)

    Abeysekera, B. A. Hirantha Sithira; Matsuda, Takahiro; Takine, Tetsuya

    In the IEEE 802.11 MAC protocol, access points (APs) are given the same priority as wireless terminals in terms of acquiring the wireless link, even though they aggregate several downlink flows. This feature leads to a serious throughput degradation of downlink flows, compared with uplink flows. In this paper, we propose a dynamic contention window control scheme for the IEEE 802.11e EDCA-based wireless LANs, in order to achieve fairness between uplink and downlink TCP flows while guaranteeing QoS requirements for real-time traffic. The proposed scheme first determines the minimum contention window size in the best-effort access category at APs, based on the number of TCP flows. It then determines the minimum and maximum contention window sizes in higher priority access categories, such as voice and video, so as to guarantee QoS requirements for these real-time traffic. Note that the proposed scheme does not require any modification to the MAC protocol at wireless terminals. Through simulation experiments, we show the effectiveness of the proposed scheme.

  15. Low cost Polymer Optical Fibre based transmission system for feeding integrated broadband wireless in-house LANs

    NARCIS (Netherlands)

    Ng'Oma, A.; Koonen, A.M.J.; Tafur Monroy, I.; Boom, van den H.P.A.; Smulders, P.F.M.; Khoe, G.D.; Visser, D. Taco; Lenstra, Daan; Schouten, F. Hugo

    2002-01-01

    A bi-directional transmission system using low cost Polymer Optical Fibre (POF) to feed the required large number of radio access points in next-generation integrated broadband wireless in-house LANs is proposed. Results from simulations and experiments show that, by tuning system parameters, a

  16. Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs with Extended Service Range

    Science.gov (United States)

    Choi, Woo-Yong

    2011-11-01

    In this paper, we propose the efficient reliable multicast MAC protocol by which the AP (Access Point) can transmit reliably its multicast data frames to the recipients in the AP's one-hop or two-hop transmission range. The AP uses the STAs (Stations) that are directly associated with itself as the relays for the data delivery to the remote recipients that cannot be reached directly from itself. Based on the connectivity information among the recipients, the reliable multicast MAC protocol optimizes the number of the RAK (Request for ACK) frame transmissions in a reasonable computational time. Numerical examples show that our proposed MAC protocol significantly enhances the MAC performance compared with the BMMM (Batch Mode Multicast MAC) protocol that is extended to support the recipients that are in the AP's one-hop or two-hop transmission range in IEEE 802.11 wireless LANs.

  17. Cluster-Based Multipolling Sequencing Algorithm for Collecting RFID Data in Wireless LANs

    Science.gov (United States)

    Choi, Woo-Yong; Chatterjee, Mainak

    2015-03-01

    With the growing use of RFID (Radio Frequency Identification), it is becoming important to devise ways to read RFID tags in real time. Access points (APs) of IEEE 802.11-based wireless Local Area Networks (LANs) are being integrated with RFID networks that can efficiently collect real-time RFID data. Several schemes, such as multipolling methods based on the dynamic search algorithm and random sequencing, have been proposed. However, as the number of RFID readers associated with an AP increases, it becomes difficult for the dynamic search algorithm to derive the multipolling sequence in real time. Though multipolling methods can eliminate the polling overhead, we still need to enhance the performance of the multipolling methods based on random sequencing. To that extent, we propose a real-time cluster-based multipolling sequencing algorithm that drastically eliminates more than 90% of the polling overhead, particularly so when the dynamic search algorithm fails to derive the multipolling sequence in real time.

  18. A Rate Adaptation Scheme According to Channel Conditions in Wireless LANs

    Science.gov (United States)

    Numoto, Daisuke; Inai, Hiroshi

    Rate adaptation in wireless LANs is to select the most suitable transmission rate automatically according to channel condition. If the channel condition is good, a station can choose a higher transmission rate, otherwise, it should choose a lower but noise-resistant transmission rate. Since IEEE 802.11 does not specify any rate adaptation scheme, several schemes have been proposed. However those schemes provide low throughput or unfair transmission opportunities among stations especially when the number of stations increases. In this paper, we propose a rate adaptation scheme under which the transmission rate quickly closes and then stays around an optimum rate even in the presence of a large number of stations. Via simulation, our scheme provides higher throughput than existing ones and almost equal fairness.

  19. A Wireless LAN and Voice Information System for Underground Coal Mine

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    2014-06-01

    Full Text Available In this paper we constructed a wireless information system, and developed a wireless voice communication subsystem based on Wireless Local Area Networks (WLAN for underground coal mine, which employs Voice over IP (VoIP technology and Session Initiation Protocol (SIP to achieve wireless voice dispatching communications. The master control voice dispatching interface and call terminal software are also developed on the WLAN ground server side to manage and implement the voice dispatching communication. A testing system for voice communication was constructed in tunnels of an underground coal mine, which was used to actually test the wireless voice communication subsystem via a network analysis tool, named Clear Sight Analyzer. In tests, the actual flow charts of registration, call establishment and call removal were analyzed by capturing call signaling of SIP terminals, and the key performance indicators were evaluated in coal mine, including average subjective value of voice quality, packet loss rate, delay jitter, disorder packet transmission and end-to- end delay. Experimental results and analysis demonstrate that the wireless voice communication subsystem developed communicates well in underground coal mine environment, achieving the designed function of voice dispatching communication.

  20. A New Three-Dimensional Indoor Positioning Mechanism Based on Wireless LAN

    Directory of Open Access Journals (Sweden)

    Jiujun Cheng

    2014-01-01

    Full Text Available The researches on two-dimensional indoor positioning based on wireless LAN and the location fingerprint methods have become mature, but in the actual indoor positioning situation, users are also concerned about the height where they stand. Due to the expansion of the range of three-dimensional indoor positioning, more features must be needed to describe the location fingerprint. Directly using a machine learning algorithm will result in the reduced ability of classification. To solve this problem, in this paper, a “divide and conquer” strategy is adopted; that is, first through k-medoids algorithm the three-dimensional location space is clustered into a number of service areas, and then a multicategory SVM with less features is created for each service area for further positioning. Our experiment shows that the error distance resolution of the approach with k-medoids algorithm and multicategory SVM is higher than that of the approach only with SVM, and the former can effectively decrease the “crazy prediction.”

  1. KeyWare: an open wireless distributed computing environment

    Science.gov (United States)

    Shpantzer, Isaac; Schoenfeld, Larry; Grindahl, Merv; Kelman, Vladimir

    1995-12-01

    Deployment of distributed applications in the wireless domain lack equivalent tools, methodologies, architectures, and network management that exist in LAN based applications. A wireless distributed computing environment (KeyWareTM) based on intelligent agents within a multiple client multiple server scheme was developed to resolve this problem. KeyWare renders concurrent application services to wireline and wireless client nodes encapsulated in multiple paradigms such as message delivery, database access, e-mail, and file transfer. These services and paradigms are optimized to cope with temporal and spatial radio coverage, high latency, limited throughput and transmission costs. A unified network management paradigm for both wireless and wireline facilitates seamless extensions of LAN- based management tools to include wireless nodes. A set of object oriented tools and methodologies enables direct asynchronous invocation of agent-based services supplemented by tool-sets matched to supported KeyWare paradigms. The open architecture embodiment of KeyWare enables a wide selection of client node computing platforms, operating systems, transport protocols, radio modems and infrastructures while maintaining application portability.

  2. Pervasive wireless environments

    CERN Document Server

    Yang, Jie; Trappe, Wade; Cheng, Jerry

    2014-01-01

    This Springer Brief provides a new approach to prevent user spoofing by using the physical properties associated with wireless transmissions to detect the presence of user spoofing. The most common method, applying cryptographic authentication, requires additional management and computational power that cannot be deployed consistently. The authors present the new approach by offering a summary of the recent research and exploring the benefits and potential challenges of this method. This brief discusses the feasibility of launching user spoofing attacks and their impact on the wireless and sen

  3. A Wireless LAN and Voice Information System for Underground Coal Mine

    OpenAIRE

    Yu Zhang; Wei Yang; Dongsheng Han; Young-Il Kim

    2014-01-01

    In this paper we constructed a wireless information system, and developed a wireless voice communication subsystem based on Wireless Local Area Networks (WLAN) for underground coal mine, which employs Voice over IP (VoIP) technology and Session Initiation Protocol (SIP) to achieve wireless voice dispatching communications. The master control voice dispatching interface and call terminal software are also developed on the WLAN ground server side to manage and implement the voice dispatching co...

  4. Security Engineering Lessons Learned for Migrating Independent LANs to an Enterprise Environment

    Science.gov (United States)

    Marchant, Robert L.; Bonneau, Thomas

    2013-01-01

    Transition from small, independent LANs into larger enterprise managed infrastructures is becoming more prominent in academia, business and government. Consolidation of IT resources into larger, more disciplined, and more professionally managed environments has significant advantages however they do bring their own unique issues to solve in order…

  5. Usability testing of wireless broadband LAN in the MEDIAN user trials

    NARCIS (Netherlands)

    Dam, C. van; Vliet, P.J. van; Schuurman, K.; Maltha, S.R.; Leyten, A.J.M.; Dirks, M.W.S.

    1999-01-01

    The main objective of the ACTS MEDIAN project is to build a high speed WCPN/LAN demonstrator system for multimedia applications and demonstrate it in user trials. The demonstrator system, consisting of one base station and two portable stations, is capable of handling high speed (up to 150 Mbit/s)

  6. Transmission History Based Distributed Adaptive Contention Window Adjustment Algorithm Cooperating with Automatic Rate Fallback for Wireless LANs

    Science.gov (United States)

    Ogawa, Masakatsu; Hiraguri, Takefumi; Nishimori, Kentaro; Takaya, Kazuhiro; Murakawa, Kazuo

    This paper proposes and investigates a distributed adaptive contention window adjustment algorithm based on the transmission history for wireless LANs called the transmission-history-based distributed adaptive contention window adjustment (THAW) algorithm. The objective of this paper is to reduce the transmission delay and improve the channel throughput compared to conventional algorithms. The feature of THAW is that it adaptively adjusts the initial contention window (CWinit) size in the binary exponential backoff (BEB) algorithm used in the IEEE 802.11 standard according to the transmission history and the automatic rate fallback (ARF) algorithm, which is the most basic algorithm in automatic rate controls. This effect is to keep CWinit at a high value in a congested state. Simulation results show that the THAW algorithm outperforms the conventional algorithms in terms of the channel throughput and delay, even if the timer in the ARF is changed.

  7. A system for ubiquitous health monitoring in the bedroom via a Bluetooth network and wireless LAN.

    Science.gov (United States)

    Choi, J M; Choi, B H; Seo, J W; Sohn, R H; Ryu, M S; Yi, W; Park, K S

    2004-01-01

    Advances in information technology have enabled ubiquitous health monitoring at home, which is particularly useful for patients, who have to live alone. We have focused on the automatic and unobtrusive measurement of biomedical signals and activities of patients. We have constructed wireless communication networks in order to transfer data. The networks consist of Bluetooth and Wireless Local Area Network (WLAN). In this paper, we present the concept of a ubiquitous-Bedroom (u-Bedroom) which is a part of a ubiquitous-House (u-House) and we present our systems for ubiquitous health monitoring.

  8. Traffic Agents for Improving QoS in Mixed Infrastructure and Ad Hoc Modes Wireless LAN

    Directory of Open Access Journals (Sweden)

    Yuan Hai-Feng

    2006-01-01

    Full Text Available As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN, which can offer high data-rate wireless multimedia services to the mobile stations (MSs in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light.

  9. A study of the impact of frequency selectivity on link adaptive wireless LAN systems

    OpenAIRE

    Armour, SMD; Doufexi, A; Nix, AR; Bull, DR

    2002-01-01

    Wireless local area networks (WLANs) supporting broadband multimedia communication are being developed and standardized around the world. The HIPERLAN/2, 802.11a and HiSWANa standards provide channel adaptive data rates between 6 and 54 Mbps in the 5GHz radio band. The link adaptation mechanism is not specified in the standards. In this paper the performance of the HIPERLAN/2 system is evaluated in terms of throughput in a range of test channels with different degrees of frequency selectivity...

  10. Fractal analysis of intraflow unidirectional delay over w-lan and w-wan environments

    OpenAIRE

    Pezaros, D. P.; Sifalakis, M.; Mathy, Laurent

    2007-01-01

    We have analysed unidirectional delay traces of a diverse set of IPv6 microflows routed over W-LAN and W-WAN environments. Using a number of time-domain and frequency-domain estimators we have examined the existence and intensity of long-range dependence in packet delay when viewed as time-series data. The correlation structures of packet delay on bulk TCP data path and UDP flows follow asymptotic decay while Hurst exponent estimates suggest from moderate to strong intensity(H->1).

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

    Directory of Open Access Journals (Sweden)

    Sungkwan Youm

    2013-01-01

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

  12. IEEE 802.11 Wireless LANs: Performance Analysis and Protocol Refinement

    Directory of Open Access Journals (Sweden)

    Chatzimisios P.

    2005-01-01

    Full Text Available The IEEE 802.11 protocol is emerging as a widely used standard and has become the most mature technology for wireless local area networks (WLANs. In this paper, we focus on the tuning of the IEEE 802.11 protocol parameters taking into consideration, in addition to throughput efficiency, performance metrics such as the average packet delay, the probability of a packet being discarded when it reaches the maximum retransmission limit, the average time to drop a packet, and the packet interarrival time. We present an analysis, which has been validated by simulation that is based on a Markov chain model commonly used in the literature. We further study the improvement on these performance metrics by employing suitable protocol parameters according to the specific communication needs of the IEEE 802.11 protocol for both basic access and RTS/CTS access schemes. We show that the use of a higher initial contention window size does not considerably degrade performance in small networks and performs significantly better in any other scenario. Moreover, we conclude that the combination of a lower maximum contention window size and a higher retry limit considerably improves performance. Results indicate that the appropriate adjustment of the protocol parameters enhances performance and improves the services that the IEEE 802.11 protocol provides to various communication applications.

  13. BER IMPROVEMENT OF WIRELESS LAN IEEE 802.11 STANDARD USING WAVELET PACKET TRANSFORMS

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar

    2012-09-01

    Full Text Available High data rates and spectral efficiency is the main requirements for wireless communication systems. Orthogonal Frequency Division Multiplexing (OFDM is a special form of multi carrier transmission used to achieve high data rates of the various WLAN standards. WLAN uses an Inverse Fast Fourier Transform (IFFT at the transmitter to modulate a high bit-rate signal onto a number of carriers and ensure orthogonality between the carriers. The FFT-OFDM has a disadvantage that it is inherently inflexible and requires a complex IFFT core. Recently, Wavelet Packet Transform is proposed as an alternate to FFT. It is a multiplexing method in which data is assigned to wavelet sub bands having different time and frequency resolutions. This paper presents a BER analysis of Fourier-based OFDM (FFT-OFDM and Wavelet Packet based OFDM (WPT-OFDM in WLAN standard (IEEE 802.11a. The performance of FFT and WPT OFDM for various modulation techniques such as PSK, DPSK and QAM for varying values of M was evaluated in AWGN Channel.

  14. A Seamless Handoff Scheme with Access Point Load Balance for Real-Time Services Support in 802.11 Wireless LANs

    Science.gov (United States)

    Manodham, Thavisak; Loyola, Luis; Miki, Tetsuya

    IEEE 802.11 wirelesses LANs (WLANs) have been rapidly deployed in enterprises, public areas, and households. Voice-over-IP (VoIP) and similar applications are now commonly used in mobile devices over wireless networks. Recent works have improved the quality of service (QoS) offering higher data rates to support various kinds of real-time applications. However, besides the need for higher data rates, seamless handoff and load balancing among APs are key issues that must be addressed in order to continue supporting real-time services across wireless LANs and providing fair services to all users. In this paper, we introduce a novel access point (AP) with two transceivers that improves network efficiency by supporting seamless handoff and traffic load balancing in a wireless network. In our proposed scheme, the novel AP uses the second transceiver to scan and find neighboring STAs in the transmission range and then sends the results to neighboring APs, which compare and analyze whether or not the STA should perform a handoff. The initial results from our simulations show that the novel AP module is more effective than the conventional scheme and a related work in terms of providing a handoff process with low latency and sharing traffic load with neighbor APs.

  15. Wireless sensor network and monitoring for environment

    OpenAIRE

    Han, Liang

    2011-01-01

    In recent years, wireless sensor network technology is developing at a surprisingly high speed. More and more fields have started to use the wireless sensor network technology and find the advantages of WSN, such as military applications, environmental observing and forecasting system, medical care, smart home, structure monitoring. The world Environmental Summit in Copenhagen on 2010 has just concluded that environment has become the world’s main concern. But regrettably the summit did no...

  16. USMMA LAN -

    Data.gov (United States)

    Department of Transportation — Local Area Network (LAN) includes all personal computers, network servers, network storage, network appliances, network switches, and Internet access to support the...

  17. A Remote WIRELESS Facility

    Directory of Open Access Journals (Sweden)

    Kees Uiterwijk

    2007-10-01

    Full Text Available Continuing need for available distance learning facilities has led to the development of a remote lab facility focusing on wireless technology. In the field of engineering there is a student need of gaining experience in set-up, monitoring and maintenance of 802.11A/B/G based wireless LAN environments.

  18. Wireless Sensor Applications in Extreme Aeronautical Environments

    Science.gov (United States)

    Wilson, William C.; Atkinson, Gary M.

    2013-01-01

    NASA aeronautical programs require rigorous ground and flight testing. Many of the testing environments can be extremely harsh. These environments include cryogenic temperatures and high temperatures (greater than 1500 C). Temperature, pressure, vibration, ionizing radiation, and chemical exposure may all be part of the harsh environment found in testing. This paper presents a survey of research opportunities for universities and industry to develop new wireless sensors that address anticipated structural health monitoring (SHM) and testing needs for aeronautical vehicles. Potential applications of passive wireless sensors for ground testing and high altitude aircraft operations are presented. Some of the challenges and issues of the technology are also presented.

  19. From early wireless to Everest.

    Science.gov (United States)

    Allen, A

    1998-01-01

    Medical information has been transmitted using wireless technologies for almost 80 years. A "wired wireless" electronic stethoscope was developed by the U.S. Army Signal Corps in the early 1920's, for potential use in ship-to-shore transmission of cardiac sounds. [Winters SR. Diagnosis by wireless. Scientific American June 11, 1921, p. 465] Today, wireless is used in a wide range of medical applications and at sites from transoceanic air flights to offshore oil platforms to Mt. Everest. 'Wireless LANs' are often used in medical environments. Typically, nurses and physicians in a hospital or clinic use hand-held "wireless thin client" pen computers that exchange patient information and images with the hospital server. Numerous companies, such as Fujitsu (article below) and Cruise Technologies (www.cruisetech.com) manufacture handheld pen-entry computers. One company, LXE, integrates radio-frequency (RF) enhanced hand-held computers specifically designed for production use within a wireless LAN (www.lxe.com). Other companies (Proxim, Symbol, and others) supply the wireless RF LAN infrastructure for the enterprise. Unfortunately, there have been problems with widespread deployment of wireless LANs. Perhaps the biggest impediment has been the lack of standards. Although an international standard (IEEE 802.11) was adopted in 1997, most wireless LAN products still are not compatible with the equipment of competing companies. A problem with the current standard for LAN adapters is that throughput is limited to 3 Mbps--compared to at least 10 Mbps, and often 100 Mbps, in a hard-wired Ethernet LAN. An II Mbps standard is due out in the next year or so, but it will be at least 2 years before standards-compliant products are available. This story profiles some of the ways that wireless is being used to overcome gaps in terrestrial and within-enterprise communication.

  20. Passive Wireless Temperature Sensor for Harsh Environments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Wireless Sensor Technologies has for several years been developing a passive Wireless Temperature Sensor (WTS) for gas turbine engine and other harsh environment...

  1. Wireless Communications in Reverberant Environments

    Science.gov (United States)

    2015-01-01

    Dedications For Mom, Dad , Michelle, Tyler, and Emily. iii Acknowledgments Moshe once told us that we would learn more from our lab mates than we would...in reverberant environments, such as industrial facilities, naval vessels, aircraft, and spacecraft, has proven challenging, because rich ...environments are characterized by rich electromagnetic scattering which is a result of the low absorption of electromagnetic radiation by the surfaces

  2. Fractal analysis of intraflow unidirectional\\ud delay over W-LAN and W-WAN environments

    OpenAIRE

    Pezaros, D.; Sifalakis, M.; Mathy, L.

    2007-01-01

    We have analysed unidirectional delay traces of a diverse\\ud set of IPv6 microflows routed over W-LAN and W-WAN\\ud environments. Using a number of time-domain and frequency-domain estimators we have examined the existence and intensity of long-range dependence in packet delay when viewed as time-series data. The correlation structures of packet delay on bulk TCP data path and UDP flows follow asymptotic decay while Hurst exponent estimates suggest from moderate to strong intensity(H->1).

  3. A New MAC Protocol with Pseudo-TDMA Behavior for Supporting Quality of Service in 802.11 Wireless LANs

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available A new medium access control (MAC protocol is proposed for quality-of-service (QoS support in wireless local area networks (WLAN. The protocol is an alternative to the recent enhancement 802.11e. A new priority policy provides the system with better performance by simulating time division multiple access (TDMA functionality. Collisions are reduced and starvation of low-priority classes is prevented by a distributed admission control algorithm. The model performance is found analytically extending previous work on this matter. The results show that a better organization of resources is achieved through this scheme. Throughput analysis is verified with OPNET simulations.

  4. Wireless sensor platform for harsh environments

    Science.gov (United States)

    Garverick, Steven L. (Inventor); Yu, Xinyu (Inventor); Toygur, Lemi (Inventor); He, Yunli (Inventor)

    2009-01-01

    Reliable and efficient sensing becomes increasingly difficult in harsher environments. A sensing module for high-temperature conditions utilizes a digital, rather than analog, implementation on a wireless platform to achieve good quality data transmission. The module comprises a sensor, integrated circuit, and antenna. The integrated circuit includes an amplifier, A/D converter, decimation filter, and digital transmitter. To operate, an analog signal is received by the sensor, amplified by the amplifier, converted into a digital signal by the A/D converter, filtered by the decimation filter to address the quantization error, and output in digital format by the digital transmitter and antenna.

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

    Directory of Open Access Journals (Sweden)

    Chang-Seop Park

    2015-01-01

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

  6. Analysis of Adaptive Control Scheme in IEEE 802.11 and IEEE 802.11e Wireless LANs

    Science.gov (United States)

    Lee, Bih-Hwang; Lai, Hui-Cheng

    In order to achieve the prioritized quality of service (QoS) guarantee, the IEEE 802.11e EDCAF (the enhanced distributed channel access function) provides the distinguished services by configuring the different QoS parameters to different access categories (ACs). An admission control scheme is needed to maximize the utilization of wireless channel. Most of papers study throughput improvement by solving the complicated multidimensional Markov-chain model. In this paper, we introduce a back-off model to study the transmission probability of the different arbitration interframe space number (AIFSN) and the minimum contention window size (CWmin). We propose an adaptive control scheme (ACS) to dynamically update AIFSN and CWmin based on the periodical monitoring of current channel status and QoS requirements to achieve the specific service differentiation at access points (AP). This paper provides an effective tuning mechanism for improving QoS in WLAN. Analytical and simulation results show that the proposed scheme outperforms the basic EDCAF in terms of throughput and service differentiation especially at high collision rate.

  7. Mobile wireless network for the urban environment

    Science.gov (United States)

    Budulas, Peter; Luu, Brian; Gopaul, Richard

    2005-05-01

    As the Army transforms into the Future Force, particular attention must be paid to operations in Complex and Urban Terrain. Our adversaries increasingly draw us into operations in the urban environment and one can presume that this trend will continue in future battles. In order to ensure that the United States Army maintains battlefield dominance, the Army Research Laboratory (ARL) is developing technology to equip our soldiers for the urban operations of the future. Sophisticated soldier borne systems will extend sensing to the individual soldier, and correspondingly, allow the soldier to establish an accurate picture of their surrounding environment utilizing information from local and remote assets. Robotic platforms will be an integral part of the future combat team. These platforms will augment the team with remote sensing modalities, task execution capabilities, and enhanced communication systems. To effectively utilize the products provided by each of these systems, collected data must be exchanged in real time to all affected entities. Therefore, the Army Research Laboratory is also developing the technology that will be required to support high bandwidth mobile communication in urban environments. This technology incorporates robotic systems that will allow connectivity in areas unreachable by traditional systems. This paper will address some of the issues of providing wireless connectivity in complex and urban terrain. It will further discuss approaches developed by the Army Research Laboratory to integrate communications capabilities into soldier and robotic systems and provide seamless connectivity between the elements of a combat team, and higher echelons.

  8. Experimental Evaluation of Wireless Communication Channels under Radiation Environment

    International Nuclear Information System (INIS)

    Wang, Quan; Bari, Ataul; Deng, Changjian; Li, Liquan

    2014-01-01

    Deployment of wireless systems in nuclear power plants has attracted a lot of attention recently. However, before wireless systems can be installed in a nuclear power plant, it is necessary to evaluate the effect of radiation environment on electromagnetic wave which is the communication media for all radio wave based wireless systems. This is particular important if the wireless systems are expected to work in a harsh and radioactive environment following a severe accident. This paper presents some results of an experiment for evaluating the effect of radiation on electromagnetic wave. The experiments involve placing transmitter antenna and receiver antenna in a hot cell with variable strength of radiation to study the attenuation effects of the radioactive media. The results indicate that radiation does not effect on the electromagnetic wave propagation. This fact should be considered during the design and deployment wireless systems in a potentially radioactive environment

  9. Risk assessment of LAN communications

    OpenAIRE

    Paylor, Mark Alan

    1992-01-01

    Approved for public release; distribution is unlimited The National Computer Security Center's (NCSC) Computer Security Requirements -- Guidance for Applying the DoD TCSEC in Specific Environments (CSC-STD-003-85) describes an environmental evaluation process which can be utilized to determine the level of trust required in a given Local Area Network (LAN) system for processing sensitive information. This thesis investigates the environmental evaluation process and applies it to the LAN en...

  10. New Wireless Sensors for Diagnostics Under Harsh Environments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — There is an acute need for robust sensors and sensor systems capable of operation in harsh environments. In particular, high temperature passive wireless surface...

  11. Cloud based spectrum manager for future wireless regulatory environment

    CSIR Research Space (South Africa)

    Masonta, MT

    2015-12-01

    Full Text Available The regulatory environment in radio frequency spectrum management lags the advancement of wireless technologies, especially in the area of cognitive radio and dynamic spectrum access. In this paper we argue that the solution towards spectrum Pareto...

  12. ATM LAN Emulation: Getting from Here to There.

    Science.gov (United States)

    Learn, Larry L., Ed.

    1995-01-01

    Discusses current LAN (local area network) configuration and explains ATM (asynchronous transfer mode) as the future telecommunications transport. Highlights include LAN emulation, which enables the interconnection of legacy LANs and the new ATM environment; virtual LANs; broadcast servers; and standards. (LRW)

  13. Field test of wireless sensor network in the nuclear environment

    International Nuclear Information System (INIS)

    Li, L.; Wang, Q.; Bari, A.; Deng, C.; Chen, D.; Jiang, J.; Alexander, Q.; Sur, B.

    2014-01-01

    Wireless sensor networks (WSNs) are appealing options for the health monitoring of nuclear power plants due to their low cost and flexibility. Before they can be used in highly regulated nuclear environments, their reliability in the nuclear environment and compatibility with existing devices have to be assessed. In situ electromagnetic interference tests, wireless signal propagation tests, and nuclear radiation hardness tests conducted on candidate WSN systems at AECL Chalk River Labs are presented. The results are favourable to WSN in nuclear applications. (author)

  14. Field test of wireless sensor network in the nuclear environment

    Energy Technology Data Exchange (ETDEWEB)

    Li, L., E-mail: lil@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Wang, Q.; Bari, A. [Univ. of Western Ontario, London, Ontario (Canada); Deng, C.; Chen, D. [Univ. of Electronic Science and Technology of China, Chengdu, Sichuan (China); Jiang, J. [Univ. of Western Ontario, London, Ontario (Canada); Alexander, Q.; Sur, B. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2014-06-15

    Wireless sensor networks (WSNs) are appealing options for the health monitoring of nuclear power plants due to their low cost and flexibility. Before they can be used in highly regulated nuclear environments, their reliability in the nuclear environment and compatibility with existing devices have to be assessed. In situ electromagnetic interference tests, wireless signal propagation tests, and nuclear radiation hardness tests conducted on candidate WSN systems at AECL Chalk River Labs are presented. The results are favourable to WSN in nuclear applications. (author)

  15. The research of nuclear experiment radiation environment wireless alarm device

    International Nuclear Information System (INIS)

    Wang Xiaoqiong; Wang Pan; Fang Fang

    2009-01-01

    This article introduces based on monolithic integrated circuit's nuclear experiment radiation environment wireless alarm device's software and hardware design. The system by G-M tube, high-pressured module, signal conditioning circuit, power source module, monolithic integrated circuit and wireless transmission module is composed. The device has low power consumption, high performance, high accuracy detection, easy maintenance, small size, simple operation, and other features, and has a broad application prospects. (authors)

  16. Source Coding for Wireless Distributed Microphones in Reverberant Environments

    DEFF Research Database (Denmark)

    Zahedi, Adel

    2016-01-01

    . However, it comes with the price of several challenges, including the limited power and bandwidth resources for wireless transmission of audio recordings. In such a setup, we study the problem of source coding for the compression of the audio recordings before the transmission in order to reduce the power...... consumption and/or transmission bandwidth by reduction in the transmission rates. Source coding for wireless microphones in reverberant environments has several special characteristics which make it more challenging in comparison with regular audio coding. The signals which are acquired by the microphones......Modern multimedia systems are more and more shifting toward distributed and networked structures. This includes audio systems, where networks of wireless distributed microphones are replacing the traditional microphone arrays. This allows for flexibility of placement and high spatial diversity...

  17. Functional Analysis of a SDR Based Bluetooth/HiperLAN Terminal Demonstrator

    NARCIS (Netherlands)

    Hoeksema, F.W.; Schiphorst, Roelof; Slump, Cornelis H.

    2001-01-01

    |In our Software Defined Radio (SDR) project we aim at combining two different types of standards, Bluetooth and HiperLAN/2 on one common hardware platform. HiperLAN/2 is a high-speed Wireless LAN (WLAN) standard, whereas Bluetooth is a low-cost and low-speed Personal Area Network (PAN) standard. An

  18. The Effects of Space Environment on Wireless Communication Devices' Performance

    OpenAIRE

    Landon, Hillyard; Dennison, JR

    2012-01-01

    This project evaluates the effects of the space environment on small radio hardware devices called Bluetooth (a proprietary open wireless technology standard for exchanging data over short distances) chips (hoovers). When electronics are exposed to the harsh environment outside the Earth's atmosphere, they sometimes do not perform as expected. The USU Getaway Away Special (GAS) team is now in the design stages of launching a CubeSat (a 10 cm cubed autonomous satellite to fly in Low Earth Orbi...

  19. Wireless Communication Enhancement Methods for Mobile Robots in Radiation Environments

    CERN Document Server

    Nattanmai Parasuraman, Ramviyas; Ferre, Manuel

    In hostile environments such as in scientific facilities where ionising radiation is a dominant hazard, reducing human interventions by increasing robotic operations are desirable. CERN, the European Organization for Nuclear Research, has around 50 km of underground scientific facilities, where wireless mobile robots could help in the operation of the accelerator complex, e.g. in conducting remote inspections and radiation surveys in different areas. The main challenges to be considered here are not only that the robots should be able to go over long distances and operate for relatively long periods, but also the underground tunnel environment, the possible presence of electromagnetic fields, radiation effects, and the fact that the robots shall in no way interrupt the operation of the accelerators. Having a reliable and robust wireless communication system is essential for successful execution of such robotic missions and to avoid situations of manual recovery of the robots in the event that the robot runs ...

  20. The Wireless ATM Architecture

    Directory of Open Access Journals (Sweden)

    R. Palitefka

    1998-06-01

    Full Text Available An overview of the proposed wireless ATM structure is provided. Wireless communication have been developed to a level where offered services can now be extended beyond voice and data. There are already wireless LANs, cordless systems offering data services and mobile data. Wireless LAN systems are basically planned for local, on-promises and in-house networking providing short distance radio or infrared links between computer system. The main challenge of wireless ATM is to harmonise the development of broadband wireless system with service B -ISDN/ATM and ATM LANs, and offer multimedia multiservice features for the support of time-sensitive voice communication, video, desktop multimedia applications, and LAN data traffic for the wireless user.

  1. Multimedia chatting system on LAN

    Science.gov (United States)

    Lung, Chu-Sheng; Wang, Chun-Chao; Lee, Ching-Long; Huang, Huang-Chen

    1994-04-01

    An interactive system designed for talking via multimedia presentation with other parties on Ethernet- LAN is proposed. Our Multimedia Chatting System will take several media services into consideration, like still image, text, pen writing, voice, and slow-motion video, to integrate a practical chatting system. The prototyping subsystem to implement the above idea is currently under development using NETBIOS communication interface and Microsoft Windows environment.

  2. Enhancing LAN performance

    CERN Document Server

    Held, Gilbert

    2004-01-01

    Enhancing LAN Performance, Fourth Edition explains how to connect geographically separated LANs with appropriate bandwidth, the issues to consider when weighing the use of multiport or dualport devices, how to estimate traffic for new networks, the effects of configuration changes on the performance of Ethernet and Token Ring networks, the design of switch-based networks that prevent traffic bottlenecks, and other critical topics. It provides the tools to address these issues in relation to specific network requirements. This volume develops mathematical models of various LAN performance issue

  3. Construct mine environment monitoring system based on wireless mesh network

    Science.gov (United States)

    Chen, Xin; Ge, Gengyu; Liu, Yinmei; Cheng, Aimin; Wu, Jun; Fu, Jun

    2018-04-01

    The system uses wireless Mesh network as a network transmission medium, and strive to establish an effective and reliable underground environment monitoring system. The system combines wireless network technology and embedded technology to monitor the internal data collected in the mine and send it to the processing center for analysis and environmental assessment. The system can be divided into two parts: the main control network module and the data acquisition terminal, and the SPI bus technology is used for mutual communication between them. Multi-channel acquisition and control interface design Data acquisition and control terminal in the analog signal acquisition module, digital signal acquisition module, and digital signal output module. The main control network module running Linux operating system, in which the transplant SPI driver, USB card driver and AODV routing protocol. As a result, the internal data collection and reporting of the mine are realized.

  4. High Temperature Wireless Communication And Electronics For Harsh Environment Applications

    Science.gov (United States)

    Hunter, G. W.; Neudeck, P. G.; Beheim, G. M.; Ponchak, G. E.; Chen, L.-Y

    2007-01-01

    In order for future aerospace propulsion systems to meet the increasing requirements for decreased maintenance, improved capability, and increased safety, the inclusion of intelligence into the propulsion system design and operation becomes necessary. These propulsion systems will have to incorporate technology that will monitor propulsion component conditions, analyze the incoming data, and modify operating parameters to optimize propulsion system operations. This implies the development of sensors, actuators, and electronics, with associated packaging, that will be able to operate under the harsh environments present in an engine. However, given the harsh environments inherent in propulsion systems, the development of engine-compatible electronics and sensors is not straightforward. The ability of a sensor system to operate in a given environment often depends as much on the technologies supporting the sensor element as the element itself. If the supporting technology cannot handle the application, then no matter how good the sensor is itself, the sensor system will fail. An example is high temperature environments where supporting technologies are often not capable of operation in engine conditions. Further, for every sensor going into an engine environment, i.e., for every new piece of hardware that improves the in-situ intelligence of the components, communication wires almost always must follow. The communication wires may be within or between parts, or from the engine to the controller. As more hardware is added, more wires, weight, complexity, and potential for unreliability is also introduced. Thus, wireless communication combined with in-situ processing of data would significantly improve the ability to include sensors into high temperature systems and thus lead toward more intelligent engine systems. NASA Glenn Research Center (GRC) is presently leading the development of electronics, communication systems, and sensors capable of prolonged stable

  5. セキュア ナ VPN テキヨウ ムセン LAN ノ コウセイ ト トクセイ

    OpenAIRE

    塩田, 宏明

    2003-01-01

    This paper presents the wireless LAN using a VPN(Virtual Private Network).The wireless LAN is based on IEEE 802.11b standard. The wireless access point(AP)is connected to a VPN server,which is connected to the lnternet.The wireless station(STA)is a VPN remote access point.The wireless LAN using a VPN between an AP and a STA is based on the Point to Point Tunneling Protocol(PPTP).

  6. Robust digital image inpainting algorithm in the wireless environment

    Science.gov (United States)

    Karapetyan, G.; Sarukhanyan, H. G.; Agaian, S. S.

    2014-05-01

    Image or video inpainting is the process/art of retrieving missing portions of an image without introducing undesirable artifacts that are undetectable by an ordinary observer. An image/video can be damaged due to a variety of factors, such as deterioration due to scratches, laser dazzling effects, wear and tear, dust spots, loss of data when transmitted through a channel, etc. Applications of inpainting include image restoration (removing laser dazzling effects, dust spots, date, text, time, etc.), image synthesis (texture synthesis), completing panoramas, image coding, wireless transmission (recovery of the missing blocks), digital culture protection, image de-noising, fingerprint recognition, and film special effects and production. Most inpainting methods can be classified in two key groups: global and local methods. Global methods are used for generating large image regions from samples while local methods are used for filling in small image gaps. Each method has its own advantages and limitations. For example, the global inpainting methods perform well on textured image retrieval, whereas the classical local methods perform poorly. In addition, some of the techniques are computationally intensive; exceeding the capabilities of most currently used mobile devices. In general, the inpainting algorithms are not suitable for the wireless environment. This paper presents a new and efficient scheme that combines the advantages of both local and global methods into a single algorithm. Particularly, it introduces a blind inpainting model to solve the above problems by adaptively selecting support area for the inpainting scheme. The proposed method is applied to various challenging image restoration tasks, including recovering old photos, recovering missing data on real and synthetic images, and recovering the specular reflections in endoscopic images. A number of computer simulations demonstrate the effectiveness of our scheme and also illustrate the main properties

  7. Miniaturized printed K shaped monopole antenna with truncated ground plane for 2.4/5.2/5.5/5.8 wireless lan applications

    Science.gov (United States)

    Chandan, Bharti, Gagandeep; Srivastava, Toolika; Rai, B. S.

    2018-04-01

    A novel truncated ground plane monopole antenna is proposed for wide band wireless local area network (WLAN) applications. The antenna contains a rectangular patch with a rectangular ring, a circular slot and a truncated ground plane printed on opposite sides of a low cost substrate FR4. The operating frequency bands for the antenna are band1 (2.4-2.88 GHz) and band 2 (4.8-6.3 GHz) with ≤ - 10 dB return loss which covers 2.4/5.2/5.5/5.8 GHz WLAN bands. The antenna is compact with overall dimension 26×40×0.8 mmł and with the dimension of patch 16×16×0.8 mm3. The two bands of antenna is obtained by cutting a rectangular ring and a circular slot in the patch and return loss is improved by cutting two rectangular slot in the ground plane. Performance measures of the antenna are shown in terms of return loss, current distribution, radiation pattern and gain. To verify the simulated results, the antenna is also fabricated and tested. The simulated and fabricated results have been found in good agreement.

  8. Lightweight context aware routing in wireless sensor networks for environments

    International Nuclear Information System (INIS)

    Aijaz, S.

    2015-01-01

    Design and implementation of a WSN (Wireless Sensor Network) that can efficiently work for a longer time period must include identification of the deployment environment context and to conform to the behavior of the sensor nodes. The context information when treated with evaluation factor becomes a process of context awareness and the evaluation factor is called the context attribute. In this paper, we consider the context factor of energy. The paper identifies analyses and evaluates efficiency of two when used in a context aware environment. Furthermore, the study also highlights the strengths and weaknesses of sensor SPIN (Sensor Protocol for Information via Negotiation) and LEACH (Low Energy Adaptive Clustering Hierarchy) protocols with respect to the support for WSN with heavy network traffic conditions. The performance has been evaluated in terms of energy efficiency, data packet transmission, network status, data management, reliability, etc. (author)

  9. A LAN Primer.

    Science.gov (United States)

    Hazari, Sunil I.

    1991-01-01

    Local area networks (LANs) are systems of computers and peripherals connected together for the purposes of electronic mail and the convenience of sharing information and expensive resources. In planning the design of such a system, the components to consider are hardware, software, transmission media, topology, operating systems, and protocols.…

  10. PHAM THI NGOC LAN

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. PHAM THI NGOC LAN. Articles written in Bulletin of Materials Science. Volume 41 Issue 1 February 2018 pp 6. Lead ions removal from aqueous solution using modified carbon nanotubes · NGUYEN DUC VU QUYEN TRAN NGOC TUYEN DINH QUANG KHIEU HO VAN MINH ...

  11. Wireless Communication Technologies

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Wireless Communication Technologies. Since 1999, the wireless LAN has experienced a tremendous growth. Reasons: Adoption of industry standards. Interoperability testing. The progress of wireless equipments to higher data rates. Rapid decrease in product ...

  12. Lessons learned on solar powered wireless sensor network deployments in urban, desert environments

    KAUST Repository

    Dehwah, Ahmad H.; Mousa, Mustafa; Claudel, Christian G.

    2015-01-01

    The successful deployment of a large scale solar powered wireless sensor network in an urban, desert environment is a very complex task. Specific cities of such environments cause a variety of operational problems, ranging from hardware faults

  13. New approach to wireless data communication in a propagation environment

    Science.gov (United States)

    Hunek, Wojciech P.; Majewski, Paweł

    2017-10-01

    This paper presents a new idea of perfect signal reconstruction in multivariable wireless communications systems including a different number of transmitting and receiving antennas. The proposed approach is based on the polynomial matrix S-inverse associated with Smith factorization. Crucially, the above mentioned inverse implements the so-called degrees of freedom. It has been confirmed by simulation study that the degrees of freedom allow to minimalize the negative impact of the propagation environment in terms of increasing the robustness of whole signal reconstruction process. Now, the parasitic drawbacks in form of dynamic ISI and ICI effects can be eliminated in framework described by polynomial calculus. Therefore, the new method guarantees not only reducing the financial impact but, more importantly, provides potentially the lower consumption energy systems than other classical ones. In order to show the potential of new approach, the simulation studies were performed by author's simulator based on well-known OFDM technique.

  14. Surface Acoustic Wave Devices for Harsh Environment Wireless Sensing

    Directory of Open Access Journals (Sweden)

    David W. Greve

    2013-05-01

    Full Text Available Langasite surface acoustic wave devices can be used to implement harsh-environment wireless sensing of gas concentration and temperature. This paper reviews prior work on the development of langasite surface acoustic wave devices, followed by a report of recent progress toward the implementation of oxygen gas sensors. Resistive metal oxide films can be used as the oxygen sensing film, although development of an adherent barrier layer will be necessary with the sensing layers studied here to prevent interaction with the langasite substrate. Experimental results are presented for the performance of a langasite surface acoustic wave oxygen sensor with tin oxide sensing layer, and these experimental results are correlated with direct measurements of the sensing layer resistivity.

  15. Extreme-Environment Silicon-Carbide (SiC) Wireless Sensor Suite

    Science.gov (United States)

    Yang, Jie

    2015-01-01

    Phase II objectives: Develop an integrated silicon-carbide wireless sensor suite capable of in situ measurements of critical characteristics of NTP engine; Compose silicon-carbide wireless sensor suite of: Extreme-environment sensors center, Dedicated high-temperature (450 deg C) silicon-carbide electronics that provide power and signal conditioning capabilities as well as radio frequency modulation and wireless data transmission capabilities center, An onboard energy harvesting system as a power source.

  16. Wireless local area network in a prehospital environment

    Directory of Open Access Journals (Sweden)

    Grimes Gary J

    2004-08-01

    Full Text Available Abstract Background Wireless local area networks (WLANs are considered the next generation of clinical data network. They open the possibility for capturing clinical data in a prehospital setting (e.g., a patient's home using various devices, such as personal digital assistants, laptops, digital electrocardiogram (EKG machines, and even cellular phones, and transmitting the captured data to a physician or hospital. The transmission rate is crucial to the applicability of the technology in the prehospital setting. Methods We created two separate WLANs to simulate a virtual local are network environment such as in a patient's home or an emergency room (ER. The effects of different methods of data transmission, number of clients, and roaming among different access points on the file transfer rate were determined. Results The present results suggest that it is feasible to transfer small files such as patient demographics and EKG data from the patient's home to the ER at a reasonable speed. Encryption, user control, and access control were implemented and results discussed. Conclusions Implementing a WLAN in a centrally managed and multiple-layer-controlled access control server is the key to ensuring its security and accessibility. Future studies should focus on product capacity, speed, compatibility, interoperability, and security management.

  17. Wireless Connectivity to ATM Communication Grid

    National Research Council Canada - National Science Library

    Rajaravivarma, Veeramuthu

    1998-01-01

    The AFOSR funds were used to purchase a 12 port Fore ATM switch, ATM network interface cards, a SUN UltraSPARC workstation, Lucent WavePoint wireless bridge, and Lucent WaveLAN wireless network interface cards...

  18. Wireless sensors in industrial time-critical environments

    CERN Document Server

    Cecilio, José

    2013-01-01

    This book introduces the components, operations, industry protocols and standards of distributed control system (DCS), and shows how to include wireless technology in their design while guaranteeing the desired operation characteristics.

  19. New Wireless Sensors for Diagnostics Under Harsh Environments, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — High-temperature passive wireless surface acoustic wave (SAW) sensors are highly desirable for improving safety and efficiency in aviation and space vehicles. This...

  20. Mastering wireless penetration testing for highly secured environments

    CERN Document Server

    Johns, Aaron

    2015-01-01

    This book is intended for security professionals who want to enhance their wireless penetration testing skills and knowledge. Since this book covers advanced techniques, you will need some previous experience in computer security and networking.

  1. Wireless Local Area Network (WLAN) Vulnerability Assessment and Security

    National Research Council Canada - National Science Library

    Kessel, Adam; Goodwin, Shane

    2005-01-01

    The proliferation of wireless computer equipment and Local Area Networks (LANs) create an increasingly common and growing threat to Marine Corps Network infrastructure and communication security (COMSEC...

  2. Evaluation of wireless Local Area Networks

    Science.gov (United States)

    McBee, Charles L.

    1993-09-01

    This thesis is an in-depth evaluation of the current wireless Local Area Network (LAN) technologies. Wireless LAN's consist of three technologies: they are infrared light, microwave, and spread spectrum. When the first wireless LAN's were introduced, they were unfavorably labeled slow, expensive, and unreliable. The wireless LAN's of today are competitively priced, more secure, easier to install, and provide equal to or greater than the data throughput of unshielded twisted pair cable. Wireless LAN's are best suited for organizations that move office staff frequently, buildings that have historical significance, or buildings that have asbestos. Additionally, an organization may realize a cost savings of between $300 to $1,200 each time a node is moved. Current wireless LAN technologies have a positive effect on LAN standards being developed by the Defense Information System Agency (DISA). DoD as a whole is beginning to focus on wireless LAN's and mobile communications. If system managers want to remain successful, they need to stay abreast of this technology.

  3. An abstract model of rogue code insertion into radio frequency wireless networks. The effects of computer viruses on the Program Management Office

    Science.gov (United States)

    Feudo, Christopher V.

    1994-04-01

    This dissertation demonstrates that inadequately protected wireless LANs are more vulnerable to rogue program attack than traditional LANs. Wireless LANs not only run the same risks as traditional LANs, but they also run additional risks associated with an open transmission medium. Intruders can scan radio waves and, given enough time and resources, intercept, analyze, decipher, and reinsert data into the transmission medium. This dissertation describes the development and instantiation of an abstract model of the rogue code insertion process into a DOS-based wireless communications system using radio frequency (RF) atmospheric signal transmission. The model is general enough to be applied to widely used target environments such as UNIX, Macintosh, and DOS operating systems. The methodology and three modules, the prober, activator, and trigger modules, to generate rogue code and insert it into a wireless LAN were developed to illustrate the efficacy of the model. Also incorporated into the model are defense measures against remotely introduced rogue programs and a cost-benefit analysis that determined that such defenses for a specific environment were cost-justified.

  4. SSIART: Opening the Way to Wireless Sensor Networks On-Board Spacecraft with an Inter-Agency Research Environment

    Science.gov (United States)

    Gunes-Lasnet, Sev; Dufour, Jean-Francois

    2012-08-01

    The potential uses and benefits of wireless technologies in space are very broad. Since many years the CCSDS SOIS wireless working group has worked at the identification of key applications for which wireless would bring benefits, and at supporting the deployment of wireless in space thanks to documents, in particular a Green informative book and magenta books presenting recommended practices.The Smart Sensor Inter-Agency Research Test bench (SSIART) is being designed to provide the space Agencies and the Industry with a reference smart sensor platform to test wireless sensor technologies in reference representative applications and RF propagation environments, while promoting these technologies at the same time.

  5. Applications of Wireless Sensor Networks in Marine Environment Monitoring: A Survey

    Science.gov (United States)

    Xu, Guobao; Shen, Weiming; Wang, Xianbin

    2014-01-01

    With the rapid development of society and the economy, an increasing number of human activities have gradually destroyed the marine environment. Marine environment monitoring is a vital problem and has increasingly attracted a great deal of research and development attention. During the past decade, various marine environment monitoring systems have been developed. The traditional marine environment monitoring system using an oceanographic research vessel is expensive and time-consuming and has a low resolution both in time and space. Wireless Sensor Networks (WSNs) have recently been considered as potentially promising alternatives for monitoring marine environments since they have a number of advantages such as unmanned operation, easy deployment, real-time monitoring, and relatively low cost. This paper provides a comprehensive review of the state-of-the-art technologies in the field of marine environment monitoring using wireless sensor networks. It first describes application areas, a common architecture of WSN-based oceanographic monitoring systems, a general architecture of an oceanographic sensor node, sensing parameters and sensors, and wireless communication technologies. Then, it presents a detailed review of some related projects, systems, techniques, approaches and algorithms. It also discusses challenges and opportunities in the research, development, and deployment of wireless sensor networks for marine environment monitoring. PMID:25215942

  6. Design And Planning Of E- Learning EnvironmentE-Education System On Heterogeneous Wireless Network Control System

    Directory of Open Access Journals (Sweden)

    ThandarOo

    2015-06-01

    Full Text Available Abstract The purpose of this research is to provide a more efficient and effective communication method between teacher and student with the use of heterogeneous network. Moreover the effective use of heterogeneous network can be emphasized. The system of e-education can develop utilizing wireless network.The e-Education system can help students to communicate with their teacher more easily and effectively using a heterogeneous wireless network system. In this wireless network system students who are blind or dumb will also be able to communicate and learn from the teacher as normal students can do. All the devices or laptops will be connected on wireless LAN. Even when the teacher is not around he will be able to help his students with their study or give instructions easily by using the mobile phone to send text or voice signal. When the teacher sends information to the dumb student it will be converted into sign language for the student to be able to understand. When the dumb student sends the information to the teacher it will be converted into text for the teacher to understand. For the blind student text instructions from the teacher will be converted into audio signal using text-to-speech conversion.Thus the performance of heterogeneous wireless network model can evaluate by using Robust Optimization Method. Therefore the e-Education systems performance improves by evaluating Robust Optimization Method.

  7. On the Relevance of Using OpenWireless Sensor Networks in Environment Monitoring

    Directory of Open Access Journals (Sweden)

    Antoine B. Bagula

    2009-06-01

    Full Text Available This paper revisits the problem of the readiness for field deployments of wireless- sensor networks by assessing the relevance of using Open Hardware and Software motes for environment monitoring. We propose a new prototype wireless sensor network that finetunes SquidBee motes to improve the life-time and sensing performance of an environment monitoring system that measures temperature, humidity and luminosity. Building upon two outdoor sensing scenarios, we evaluate the performance of the newly proposed energy-aware prototype solution in terms of link quality when expressed by the Received Signal Strength, Packet Loss and the battery lifetime. The experimental results reveal the relevance of using the Open Hardware and Software motes when setting up outdoor wireless sensor networks.

  8. Tactical Wireless Networking in Coalition Environments: Implementing an IEEE 802.20 Wireless End-User Network Utilizing FLASH-OFDM to Provide a Secure Mobile Extension to Existing WAN

    National Research Council Canada - National Science Library

    Parrish, William J; Tovar, Daniel R

    2005-01-01

    This thesis will focus on the area of 802.20 wireless networking as a feasible "last mile" solution to wireless access in a tactical coalition environment and will be implemented into a series of experiments...

  9. Broadband Microwave Wireless Power Transfer for Weak-Signal and Multipath Environments

    Science.gov (United States)

    Barton, Richard J.

    2014-01-01

    In this paper, we study the potential benefits of using relatively broadband wireless power transmission WPT strategies in both weak-signal and multipath environments where traditional narrowband strategies can be very inefficient. The paper is primarily a theoretical and analytical treatment of the problem that attempts to derive results that are widely applicable to many different WPT applications, including space solar power SSP.

  10. A Rapid Prototyping Environment for Wireless Communication Embedded Systems

    Directory of Open Access Journals (Sweden)

    Bryan A. Jones

    2003-05-01

    Full Text Available This paper introduces a rapid prototyping methodology which overcomes important barriers in the design and implementation of digital signal processing (DSP algorithms and systems on embedded hardware platforms, such as cellular phones. This paper describes rapid prototyping in terms of a simulation/prototype bridge and in terms of appropriate language design. The simulation/prototype bridge combines the strengths of simulation and of prototyping, allowing the designer to develop and evaluate next-generation communications systems, partly in simulation on a host computer and partly as a prototype on embedded hardware. Appropriate language design allows designers to express a communications system as a block diagram, in which each block represents an algorithm specified by a set of equations. Software tools developed for this paper implement both concepts, and have been successfully used in the development of a next-generation code division multiple access (CDMA cellular wireless communications system.

  11. Implementation of virtual LANs over ATM WANs

    Science.gov (United States)

    Braun, Torsten; Maehler, Martin

    1998-09-01

    Virtual LANs (VLANs) allow to interconnect users over campus or wide area networks and gives the users the impression as they would be connected to the same local area network (LAN). The implementation of VLANs is based on ATM Forum's LAN Emulation and LAN/ATM switches providing interconnection of emulated LANs over ATM and the LAN ports to which the user's end systems are attached to. The paper discusses possible implementation architectures and describes advanced features such as ATM short-cuts, QoS, and redundancy concepts.

  12. K-12 Local Network (LAN) Design Guide

    National Research Council Canada - National Science Library

    Horton, Cody

    1998-01-01

    ...) educators preparing to design and implement LANs in K-12 schools and libraries. Data was collected during the implementation of LANs in K-12 schools of the Monterey Peninsula Uniform School District (MPUSD...

  13. Design of wireless communication systems for nuclear power plant environments

    International Nuclear Information System (INIS)

    Kadri, A.

    2007-01-01

    The problem of low-SNR (Signal-to-Noise ratio) digital communication system design in man-made electromagnetic environment within a nuclear power plant is addressed. A canonical structure of the low-SNR receiver is derived and analyzed for its bit error rate performance. The parameters that affect the error rate performance are identified and illustrated. Several well-known digital modulations are considered. It is shown that the receiver structure is dependent on the first-order probability density function of the noise environment. Thus, we offer comments for its robust implementation and its effect on bit error rate performance. We model the EM environment within the nuclear power plant to be e - mixture model, the parameters of which can be estimated to fit the environment. (author)

  14. Virtual File System Mounting amp Searching With Network JVM For LAN

    Directory of Open Access Journals (Sweden)

    Nikita Kamble

    2015-08-01

    Full Text Available Computer technology has rapidly grown over past decades. Most of this can be attributed to the Internet as many computers now have a need to be networked together to establish an online connection. A local area network is a group of computers and associated devices that share a common communication line or wireless link to the service. Typically a LAN compasses computers and peripherals connected to a secure server within a small geographic area such as an office building or home computer and other mobile devices that share resources such as printer or network storage. A LAN is contrasted in principle to a wide area networkWANwhich covers a larger geographic distance and may involve leased telecom circuits while the media for LANs are locally managed. Ethernet are twisted pair cabling amp Wi-Fi are the two most common transmission technologies in use for LAN. The rise of virtualization has fueled the development of virtual LANWLANwhich allows network administrator to logically group network nodes amp partition their networks without the need for major infrastructure changes. In some situations a wireless LAN or Wi-Fi maybe preferable to a wired LAN because of its flexibility amp cost. Companies are asserting WLANs as a replacement for their wired infrastructure as the number of smart phones tablets amp other mobile devices proliferates.

  15. Wireless microwave acoustic sensor system for condition monitoring in power plant environments

    Energy Technology Data Exchange (ETDEWEB)

    Pereira da Cunha, Mauricio [Univ. of Maine, Orno, ME (United States)

    2017-03-30

    This project successfully demonstrated novel wireless microwave acoustic temperature and pressure sensors that can be embedded into equipment and structures located in fossil fuel power plant environments to monitor the condition of components such as steam headers, re-heat lines, water walls, burner tubes, and power turbines. The wireless microwave acoustic sensor technology researched and developed through a collaborative partnership between the University of Maine and Environetix Technologies Corporation can provide a revolutionary impact in the power industry since it is anticipated that the wireless sensors will deliver reliable real-time sensing information in harsh power plant conditions that involve temperatures up to 1100oC and pressures up to 750 psi. The work involved the research and development of novel high temperature harsh environment thin film electrodes, piezoelectric smart microwave acoustic sensing elements, sensor encapsulation materials that were engineered to function over long times up to 1100oC, and a radio-frequency (RF) wireless interrogation electronics unit that are located both inside and outside the high temperature harsh environment. The UMaine / Environetix team have interacted with diverse power plant facilities, and identified as a testbed a local power generation facility, which burns municipal solid waste (MSW), the Penobscot Energy Recovery Company (PERC), Orrington, Maine. In this facility Environetix / UMaine successfully implemented and tested multiple wireless temperature sensor systems within the harsh-environment of the economizer chamber and at the boiler tubes, transferring the developed technology to the power plant environment to perform real-time sensor monitoring experiments under typical operating conditions, as initially targeted in the project. The wireless microwave acoustic sensor technology developed under this project for power plant applications offers several significant advantages including wireless

  16. An Empirical Path-Loss Model for Wireless Channels in Indoor Short-Range Office Environment

    Directory of Open Access Journals (Sweden)

    Ye Wang

    2012-01-01

    Full Text Available A novel empirical path-loss model for wireless indoor short-range office environment at 4.3–7.3 GHz band is presented. The model is developed based on the experimental datum sampled in 30 office rooms in both line of sight (LOS and non-LOS (NLOS scenarios. The model is characterized as the path loss to distance with a Gaussian random variable X due to the shadow fading by using linear regression. The path-loss exponent n is fitted by the frequency using power function and modeled as a frequency-dependent Gaussian variable as the standard deviation σ of X. The presented works should be available for the research of wireless channel characteristics under universal indoor short-distance environments in the Internet of Things (IOT.

  17. DSTiPE Algorithm for Fuzzy Spatio-Temporal Risk Calculation in Wireless Environments

    Energy Technology Data Exchange (ETDEWEB)

    Kurt Derr; Milos Manic

    2008-09-01

    Time and location data play a very significant role in a variety of factory automation scenarios, such as automated vehicles and robots, their navigation, tracking, and monitoring, to services of optimization and security. In addition, pervasive wireless capabilities combined with time and location information are enabling new applications in areas such as transportation systems, health care, elder care, military, emergency response, critical infrastructure, and law enforcement. A person/object in proximity to certain areas for specific durations of time may pose a risk hazard either to themselves, others, or the environment. This paper presents a novel fuzzy based spatio-temporal risk calculation DSTiPE method that an object with wireless communications presents to the environment. The presented Matlab based application for fuzzy spatio-temporal risk cluster extraction is verified on a diagonal vehicle movement example.

  18. Wireless Capacitive Pressure Sensor With Directional RF Chip Antenna for High Temperature Environments

    Science.gov (United States)

    Scardelletti, M. C.; Jordan, J. L.; Ponchak, G. E.; Zorman, C. A.

    2015-01-01

    This paper presents the design, fabrication and characterization of a wireless capacitive pressure sensor with directional RF chip antenna that is envisioned for the health monitoring of aircraft engines operating in harsh environments. The sensing system is characterized from room temperature (25 C) to 300 C for a pressure range from 0 to 100 psi. The wireless pressure system consists of a Clapp-type oscillator design with a capacitive MEMS pressure sensor located in the LC-tank circuit of the oscillator. Therefore, as the pressure of the aircraft engine changes, so does the output resonant frequency of the sensing system. A chip antenna is integrated to transmit the system output to a receive antenna 10 m away.The design frequency of the wireless pressure sensor is 127 MHz and a 2 increase in resonant frequency over the temperature range of 25 to 300 C from 0 to 100 psi is observed. The phase noise is less than minus 30 dBcHz at the 1 kHz offset and decreases to less than minus 80 dBcHz at 10 kHz over the entire temperature range. The RF radiation patterns for two cuts of the wireless system have been measured and show that the system is highly directional and the MEMS pressure sensor is extremely linear from 0 to 100 psi.

  19. Lessons learned on solar powered wireless sensor network deployments in urban, desert environments

    KAUST Repository

    Dehwah, Ahmad H.

    2015-05-01

    The successful deployment of a large scale solar powered wireless sensor network in an urban, desert environment is a very complex task. Specific cities of such environments cause a variety of operational problems, ranging from hardware faults to operational challenges, for instance due to the high variability of solar energy availability. Even a seemingly functional sensor network created in the lab does not guarantee reliable long term operation, which is absolutely necessary given the cost and difficulty of accessing sensor nodes in urban environments. As part of a larger traffic flow wireless sensor network project, we conducted several deployments in the last two years to evaluate the long-term performance of solar-powered urban wireless sensor networks in a desert area. In this article, we share our experiences in all domains of sensor network operations, from the conception of hardware to post-deployment analysis, including operational constraints that directly impact the software that can be run. We illustrate these experiences using numerous experimental results, and present multiple unexpected operational problems as well as some possible solutions to address them. We also show that current technology is far from meeting all operational constraints for these demanding applications, in which sensor networks are to operate for years to become economically appealing.

  20. A Wearable Wireless Sensor Network for Indoor Smart Environment Monitoring in Safety Applications.

    Science.gov (United States)

    Antolín, Diego; Medrano, Nicolás; Calvo, Belén; Pérez, Francisco

    2017-02-14

    This paper presents the implementation of a wearable wireless sensor network aimed at monitoring harmful gases in industrial environments. The proposed solution is based on a customized wearable sensor node using a low-power low-rate wireless personal area network (LR-WPAN) communications protocol, which as a first approach measures CO₂ concentration, and employs different low power strategies for appropriate energy handling which is essential to achieving long battery life. These wearables nodes are connected to a deployed static network and a web-based application allows data storage, remote control and monitoring of the complete network. Therefore, a complete and versatile remote web application with a locally implemented decision-making system is accomplished, which allows early detection of hazardous situations for exposed workers.

  1. A Wearable Wireless Sensor Network for Indoor Smart Environment Monitoring in Safety Applications

    Directory of Open Access Journals (Sweden)

    Diego Antolín

    2017-02-01

    Full Text Available This paper presents the implementation of a wearable wireless sensor network aimed at monitoring harmful gases in industrial environments. The proposed solution is based on a customized wearable sensor node using a low-power low-rate wireless personal area network (LR-WPAN communications protocol, which as a first approach measures CO2 concentration, and employs different low power strategies for appropriate energy handling which is essential to achieving long battery life. These wearables nodes are connected to a deployed static network and a web-based application allows data storage, remote control and monitoring of the complete network. Therefore, a complete and versatile remote web application with a locally implemented decision-making system is accomplished, which allows early detection of hazardous situations for exposed workers.

  2. A Harsh Environment-Oriented Wireless Passive Temperature Sensor Realized by LTCC Technology

    Directory of Open Access Journals (Sweden)

    Qiulin Tan

    2014-03-01

    Full Text Available To meet measurement needs in harsh environments, such as high temperature and rotating applications, a wireless passive Low Temperature Co-fired Ceramics (LTCC temperature sensor based on ferroelectric dielectric material is presented in this paper. As a LC circuit which consists of electrically connected temperature sensitive capacitor and invariable planar spiral inductor, the sensor has its resonant frequency shift with the variation in temperature. Within near-filed coupling distance, the variation in resonant frequency of the sensor can be detected contactlessly by extracting the impedance parameters of an external antenna. Ferroelectric ceramic, which has temperature sensitive permittivity, is used as the dielectric. The fabrication process of the sensor, which differs from conventional LTCC technology, is described in detail. The sensor is tested three times from room temperature to 700 °C, and considerable repeatability and sensitivity are shown, thus the feasibility of high performance wireless passive temperature sensor realized by LTCC technology is demonstrated.

  3. Data converters for wireless standards

    CERN Document Server

    Shi, Chunlei

    2002-01-01

    Wireless communication is witnessing tremendous growth with proliferation of different standards covering wide, local and personal area networks (WAN, LAN and PAN). The trends call for designs that allow 1) smooth migration to future generations of wireless standards with higher data rates for multimedia applications, 2) convergence of wireless services allowing access to different standards from the same wireless device, 3) inter-continental roaming. This requires designs that work across multiple wireless standards, can easily be reused, achieve maximum hardware share at a minimum power consumption levels particularly for mobile battery-operated devices.

  4. Wireless Mid-Infrared Spectroscopy Sensor Network for Automatic Carbon Dioxide Fertilization in a Greenhouse Environment

    Directory of Open Access Journals (Sweden)

    Jianing Wang

    2016-11-01

    Full Text Available In this paper, a wireless mid-infrared spectroscopy sensor network was designed and implemented for carbon dioxide fertilization in a greenhouse environment. A mid-infrared carbon dioxide (CO2 sensor based on non-dispersive infrared (NDIR with the functionalities of wireless communication and anti-condensation prevention was realized as the sensor node. Smart transmission power regulation was applied in the wireless sensor network, according to the Received Signal Strength Indication (RSSI, to realize high communication stability and low-power consumption deployment. Besides real-time monitoring, this system also provides a CO2 control facility for manual and automatic control through a LabVIEW platform. According to simulations and field tests, the implemented sensor node has a satisfying anti-condensation ability and reliable measurement performance on CO2 concentrations ranging from 30 ppm to 5000 ppm. As an application, based on the Fuzzy proportional, integral, and derivative (PID algorithm realized on a LabVIEW platform, the CO2 concentration was regulated to some desired concentrations, such as 800 ppm and 1200 ppm, in 30 min with a controlled fluctuation of <±35 ppm in an acre of greenhouse.

  5. Challenges in Wireless System Integration as Enablers for Indoor Context Aware Environments

    Directory of Open Access Journals (Sweden)

    Peio López-Iturri

    2017-07-01

    Full Text Available The advent of fully interactive environments within Smart Cities and Smart Regions requires the use of multiple wireless systems. In the case of user-device interaction, which finds multiple applications such as Ambient Assisted Living, Intelligent Transportation Systems or Smart Grids, among others, large amount of transceivers are employed in order to achieve anytime, anyplace and any device connectivity. The resulting combination of heterogeneous wireless network exhibits fundamental limitations derived from Coverage/Capacity relations, as a function of required Quality of Service parameters, required bit rate, energy restrictions and adaptive modulation and coding schemes. In this context, inherent transceiver density poses challenges in overall system operation, given by multiple node operation which increases overall interference levels. In this work, a deterministic based analysis applied to variable density wireless sensor network operation within complex indoor scenarios is presented, as a function of topological node distribution. The extensive analysis derives interference characterizations, both for conventional transceivers as well as wearables, which provide relevant information in terms of individual node configuration as well as complete network layout.

  6. A Harsh Environment Wireless Pressure Sensing Solution Utilizing High Temperature Electronics

    Science.gov (United States)

    Yang, Jie

    2013-01-01

    Pressure measurement under harsh environments, especially at high temperatures, is of great interest to many industries. The applicability of current pressure sensing technologies in extreme environments is limited by the embedded electronics which cannot survive beyond 300 °C ambient temperature as of today. In this paper, a pressure signal processing and wireless transmission module based on the cutting-edge Silicon Carbide (SiC) devices is designed and developed, for a commercial piezoresistive MEMS pressure sensor from Kulite Semiconductor Products, Inc. Equipped with this advanced high-temperature SiC electronics, not only the sensor head, but the entire pressure sensor suite is capable of operating at 450 °C. The addition of wireless functionality also makes the pressure sensor more flexible in harsh environments by eliminating the costly and fragile cable connections. The proposed approach was verified through prototype fabrication and high temperature bench testing from room temperature up to 450 °C. This novel high-temperature pressure sensing technology can be applied in real-time health monitoring of many systems involving harsh environments, such as military and commercial turbine engines. PMID:23447006

  7. A hybrid stochastic approach for self-location of wireless sensors in indoor environments.

    Science.gov (United States)

    Lloret, Jaime; Tomas, Jesus; Garcia, Miguel; Canovas, Alejandro

    2009-01-01

    Indoor location systems, especially those using wireless sensor networks, are used in many application areas. While the need for these systems is widely proven, there is a clear lack of accuracy. Many of the implemented applications have high errors in their location estimation because of the issues arising in the indoor environment. Two different approaches had been proposed using WLAN location systems: on the one hand, the so-called deductive methods take into account the physical properties of signal propagation. These systems require a propagation model, an environment map, and the position of the radio-stations. On the other hand, the so-called inductive methods require a previous training phase where the system learns the received signal strength (RSS) in each location. This phase can be very time consuming. This paper proposes a new stochastic approach which is based on a combination of deductive and inductive methods whereby wireless sensors could determine their positions using WLAN technology inside a floor of a building. Our goal is to reduce the training phase in an indoor environment, but, without an loss of precision. Finally, we compare the measurements taken using our proposed method in a real environment with the measurements taken by other developed systems. Comparisons between the proposed system and other hybrid methods are also provided.

  8. A Hybrid Stochastic Approach for Self-Location of Wireless Sensors in Indoor Environments

    Directory of Open Access Journals (Sweden)

    Alejandro Canovas

    2009-05-01

    Full Text Available Indoor location systems, especially those using wireless sensor networks, are used in many application areas. While the need for these systems is widely proven, there is a clear lack of accuracy. Many of the implemented applications have high errors in their location estimation because of the issues arising in the indoor environment. Two different approaches had been proposed using WLAN location systems: on the one hand, the so-called deductive methods take into account the physical properties of signal propagation. These systems require a propagation model, an environment map, and the position of the radio-stations. On the other hand, the so-called inductive methods require a previous training phase where the system learns the received signal strength (RSS in each location. This phase can be very time consuming. This paper proposes a new stochastic approach which is based on a combination of deductive and inductive methods whereby wireless sensors could determine their positions using WLAN technology inside a floor of a building. Our goal is to reduce the training phase in an indoor environment, but, without an loss of precision. Finally, we compare the measurements taken using our proposed method in a real environment with the measurements taken by other developed systems. Comparisons between the proposed system and other hybrid methods are also provided.

  9. Perancangan & Simlasi Security LAN Dengan Perangkat CISCO

    OpenAIRE

    Asma, Nur

    2013-01-01

    Perancangan ini dikembangkan dengan menggunakan perangkat lunak CISCO paket tracer. Biasanya dalam satu gedung fakultas mahasiswa berada dalam satu LAN sedangkan komputer dosen berada pada LAN lain. Hal ini sepertinya sudah sewajarna terjadi mengingat keadaan jaringan yang terhubung secara fisik. Jadi tujuan perancangan ini adalah membangun sistem keamanan LAN dengan sistem VLAN dan dijalankan dengan perangkat CISCO dari paket tracer. VLAN (Virtual Local Area Network) merupakan salah satu tek...

  10. Wireless sensor network-based greenhouse environment monitoring and automatic control system for dew condensation prevention.

    Science.gov (United States)

    Park, Dae-Heon; Park, Jang-Woo

    2011-01-01

    Dew condensation on the leaf surface of greenhouse crops can promote diseases caused by fungus and bacteria, affecting the growth of the crops. In this paper, we present a WSN (Wireless Sensor Network)-based automatic monitoring system to prevent dew condensation in a greenhouse environment. The system is composed of sensor nodes for collecting data, base nodes for processing collected data, relay nodes for driving devices for adjusting the environment inside greenhouse and an environment server for data storage and processing. Using the Barenbrug formula for calculating the dew point on the leaves, this system is realized to prevent dew condensation phenomena on the crop's surface acting as an important element for prevention of diseases infections. We also constructed a physical model resembling the typical greenhouse in order to verify the performance of our system with regard to dew condensation control.

  11. Wireless Sensor Network-Based Greenhouse Environment Monitoring and Automatic Control System for Dew Condensation Prevention

    Science.gov (United States)

    Park, Dae-Heon; Park, Jang-Woo

    2011-01-01

    Dew condensation on the leaf surface of greenhouse crops can promote diseases caused by fungus and bacteria, affecting the growth of the crops. In this paper, we present a WSN (Wireless Sensor Network)-based automatic monitoring system to prevent dew condensation in a greenhouse environment. The system is composed of sensor nodes for collecting data, base nodes for processing collected data, relay nodes for driving devices for adjusting the environment inside greenhouse and an environment server for data storage and processing. Using the Barenbrug formula for calculating the dew point on the leaves, this system is realized to prevent dew condensation phenomena on the crop’s surface acting as an important element for prevention of diseases infections. We also constructed a physical model resembling the typical greenhouse in order to verify the performance of our system with regard to dew condensation control. PMID:22163813

  12. Mutual Image-Based Authentication Framework with JPEG2000 in Wireless Environment

    Directory of Open Access Journals (Sweden)

    Ginesu G

    2006-01-01

    Full Text Available Currently, together with the development of wireless connectivity, the need for a reliable and user-friendly authentication system becomes always more important. New applications, as e-commerce or home banking, require a strong level of protection, allowing for verification of legitimate users' identity and enabling the user to distinguis trusted servers from shadow ones. A novel framework for image-based authentication (IBA is then proposed and evaluated. In order to provide mutual authentication, the proposed method integrates an IBA password technique with a challenge-response scheme based on a shared secret key for image scrambling. The wireless environment is mainly addressed by the proposed system, which tries to overcome the severe constraints on security, data transmission capability, and user friendliness imposed by such environment. In order to achieve such results, the system offers a strong solution for authentication, taking into account usability and avoiding the need for hardware upgrades. Data and application scalability is provided through the JPEG2000 standard and JPIP framework.

  13. A MIMO-OFDM Testbed for Wireless Local Area Networks

    Directory of Open Access Journals (Sweden)

    Conrat Jean-Marc

    2006-01-01

    Full Text Available We describe the design steps and final implementation of a MIMO OFDM prototype platform developed to enhance the performance of wireless LAN standards such as HiperLAN/2 and 802.11, using multiple transmit and multiple receive antennas. We first describe the channel measurement campaign used to characterize the indoor operational propagation environment, and analyze the influence of the channel on code design through a ray-tracing channel simulator. We also comment on some antenna and RF issues which are of importance for the final realization of the testbed. Multiple coding, decoding, and channel estimation strategies are discussed and their respective performance-complexity trade-offs are evaluated over the realistic channel obtained from the propagation studies. Finally, we present the design methodology, including cross-validation of the Matlab, C++, and VHDL components, and the final demonstrator architecture. We highlight the increased measured performance of the MIMO testbed over the single-antenna system.

  14. Lightweight Context Aware Routing in Wireless Sensor Networks for Real Environments

    Directory of Open Access Journals (Sweden)

    Samia Aijaz

    2015-07-01

    Full Text Available Design and implementation of a WSN (Wireless Sensor Network that can efficiently work for a longer time period must include identification of the deployment environment context and to conform to the behavior of the sensor nodes. The context information when treated with evaluation factor becomes a process of context awareness and the evaluation factor is called the context attribute. In this paper, we consider the context factor of energy. The paper identifies analyses and evaluates efficiency of two when used in a context aware environment. Furthermore, the study also highlights the strengths and weaknesses of sensor SPIN (Sensor Protocol for Information via Negotiation and LEACH (Low Energy Adaptive Clustering Hierarchy protocols with respect to the support for WSN with heavy network traffic conditions. The performance has been evaluated in terms of energy efficiency, data packet transmission, network status, data management, reliability, etc.

  15. Technical experiences of implementing a wireless tracking and facial biometric verification system for a clinical environment

    Science.gov (United States)

    Liu, Brent; Lee, Jasper; Documet, Jorge; Guo, Bing; King, Nelson; Huang, H. K.

    2006-03-01

    By implementing a tracking and verification system, clinical facilities can effectively monitor workflow and heighten information security in today's growing demand towards digital imaging informatics. This paper presents the technical design and implementation experiences encountered during the development of a Location Tracking and Verification System (LTVS) for a clinical environment. LTVS integrates facial biometrics with wireless tracking so that administrators can manage and monitor patient and staff through a web-based application. Implementation challenges fall into three main areas: 1) Development and Integration, 2) Calibration and Optimization of Wi-Fi Tracking System, and 3) Clinical Implementation. An initial prototype LTVS has been implemented within USC's Healthcare Consultation Center II Outpatient Facility, which currently has a fully digital imaging department environment with integrated HIS/RIS/PACS/VR (Voice Recognition).

  16. Adaptive Power Management for Wireless Base Station in Smart Grid Environment

    OpenAIRE

    Niyato, Dusit; Lu, Xiao; Wang, Ping

    2014-01-01

    The growing concerns of a global environmental change raises a revolution on the way of utilizing energy. In wireless industry, green wireless communications has recently gained increasing attention and is expected to play a major role in reduction of electrical power consumption. In particular, actions to promote energy saving of wireless communications with regard to environmental protection are becoming imperative. To this purpose, we study a green communication system model where wireless...

  17. Demonstration of TEG-powered wireless autonomous transducer solution for condition monitoring in industrial environment

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ziyang; Patrascu, Mihai; Su, Jiale; Vullers, Ruud J.M. [imec the Netherlands, Eindhoven (Netherlands)

    2011-07-01

    Imec/Holst Centre focuses on the development of wireless autonomous transducer solution, which is poised to bring about huge impact in the sectors of health care, machinery, transportation and energy, etc. In this paper, we first showcase a TEG-powered demonstration for condition monitoring in industrial environment. Composing of sensor-actuator, front-end interface, digital signal processing unit and radio, the developed wireless sensor node can monitor the changing operating condition, i.e. the loading on a rolling-element bearing, on a rotating shaft. The use of a specially designed TEG, working in tandem with an energy storage device, can significantly improve the energy autonomy of the condition monitoring system as a whole. The different components in the demonstration are presented. Subsequently, the experimental results of vibration signature analysis are exhibited. On one hand, the presented demonstration sheds light on the huge potential of thermoelectric energy harvesting to achieve energy autonomy. On the other hand, it also points to the aspects that are in need of further development, namely miniaturization and cost reduction of energy harvesters. Aimed at the delivery of cost-effective miniaturized thermoelectric harvesting devices, imec/Holst Centre has been tackling with the relevant challenges by resorting to, but not limited to, its expertise in micromachining. An update on the latest research results is subsequently given with regard to various micromachined thermoelectric devices, fully fledged wearable TEGs with custom designed package and thermoelectric material property optimization. (orig.)

  18. Channel capacity of TDD-OFDM-MIMO for multiple access points in a wireless single-frequency-network

    DEFF Research Database (Denmark)

    Takatori, Y.; Fitzek, Frank; Tsunekawa, K.

    2005-01-01

    MIMO data transmission scheme, which combines Single-Frequency-Network (SFN) with TDD-OFDM-MIMO applied for wireless LAN networks. In our proposal, we advocate to use SFN for multiple access points (MAP) MIMO data transmission. The goal of this approach is to achieve very high channel capacity in both......The multiple-input-multiple-output (MIMO) technique is the most attractive candidate to improve the spectrum efficiency in the next generation wireless communication systems. However, the efficiency of MIMO techniques reduces in the line of sight (LOS) environments. In this paper, we propose a new...

  19. EIRP Characterization of Electrically Large Wireless Equipment with Integrated Signal Generator in a Compact Environment

    Directory of Open Access Journals (Sweden)

    Soon-Soo Oh

    2015-01-01

    Full Text Available We describe a measurement technique to characterize the equivalent isotropically radiated power (EIRP of electrically large wireless equipment in a compact environment. A modified phase-measurement method was proposed and, thus, the separation of the signal generator and radiating element was not required during the measurement. A Fresnel-to-far-field transformation was used for the fast measurement time in a compact anechoic chamber. An experimental verification of the method was carried out in a compact anechoic chamber, where the source-detector separation was approximately 1/5 of the far-field distance. The measured magnitude and phase pattern exhibited only a small error. The EIRP obtained using a Fresnel-to-far-field transformation was compared with a reference value, and the error was within 0.5 dB.

  20. Event-Based Control Strategy for Mobile Robots in Wireless Environments.

    Science.gov (United States)

    Socas, Rafael; Dormido, Sebastián; Dormido, Raquel; Fabregas, Ernesto

    2015-12-02

    In this paper, a new event-based control strategy for mobile robots is presented. It has been designed to work in wireless environments where a centralized controller has to interchange information with the robots over an RF (radio frequency) interface. The event-based architectures have been developed for differential wheeled robots, although they can be applied to other kinds of robots in a simple way. The solution has been checked over classical navigation algorithms, like wall following and obstacle avoidance, using scenarios with a unique or multiple robots. A comparison between the proposed architectures and the classical discrete-time strategy is also carried out. The experimental results shows that the proposed solution has a higher efficiency in communication resource usage than the classical discrete-time strategy with the same accuracy.

  1. Virtual File System Mounting amp Searching With Network JVM For LAN

    OpenAIRE

    Nikita Kamble; Vaishnavi Patil; Shweta Desai; Dhanashri Kasar; Mrunali Patil

    2015-01-01

    Computer technology has rapidly grown over past decades. Most of this can be attributed to the Internet as many computers now have a need to be networked together to establish an online connection. A local area network is a group of computers and associated devices that share a common communication line or wireless link to the service. Typically a LAN compasses computers and peripherals connected to a secure server within a small geographic area such as an office building or home computer and...

  2. A noncontact wireless passive radio frequency (RF) resonant pressure sensor with optimized design for applications in high-temperature environments

    International Nuclear Information System (INIS)

    Li, Chen; Tan, Qiulin; Xiong, Jijun; Jia, Pinggang; Hong, Yingping; Ren, Zhong; Luo, Tao; Liu, Jun; Xue, Chenyang; Zhang, Wendong

    2014-01-01

    A noncontact wireless passive pressure sensor based on alumina ceramic for pressure measurement is presented in this paper. A faithful pressure signal in harsh environment is captured through wireless sensing, and a novel antenna design method is developed to increase the measurement distance between the antenna and the sensor. The sensor is fabricated using a novel no-co-fired technology, and the properties of the alumina ceramic and platinum ensure the feasibility of the sensor in high-temperature environments. The experimental results show that the coupled distance between the antenna and the sensor can be up to 5.5 cm, and the designed sensor, featuring improved structural parameters, has a high responsivity (15.5 kHz kPa −1 ) in a pressure environment at room temperature. The sensor can be coupled with the antenna at 850 °C, which verifies the feasibility in high-temperature environments. (paper)

  3. WLAN versus LAN - environmental impacts of small and medium sized local area networks

    Energy Technology Data Exchange (ETDEWEB)

    Hottenroth, H.; Quack, D. [Oeko-Inst. e.V., Inst. for Applied Ecology, Freiburg (Germany); Sustainable Products and Material Flows Div., Freiburg (Germany)

    2004-07-01

    In the study presented here the environmental impacts of the infrastructure and the use of wireless LAN are investigated and compared to wired LAN. In order to determine if and under which conditions WLAN shows environmental benefits a comparison with a wired LAN was drawn on the basis of three exemplary applications. The environmental impacts of the life cycle of these applications were assessed using the method of LCA. The investigated systems include the production, the operation of the networks and their end of life stage. The three applications under investigation were the following: application 1: a peer-to-peer connection of two computers; application 2: a small network consisting of three computers like it is used in households and small offices (SOHO) and application 3: an office network consisting of 20 computers. The results showed no significant differences between the two alternatives for the applications 1 and 2 taking into account cumulative energy demand, global warming potential, acidification potential and photochemical oxidation potential as impact categories. In contrast to this a significant advantage for the wireless solution could be identified for the third application. Concerning electronic waste-arise, the wireless solution is advantageous for all three applications. From the results recommendations for equipment options, net structure, and use behaviour of local area networks are derived. (orig.)

  4. An Integrated Environment Monitoring System for Underground Coal Mines—Wireless Sensor Network Subsystem with Multi-Parameter Monitoring

    OpenAIRE

    Zhang, Yu; Yang, Wei; Han, Dongsheng; Kim, Young-Il

    2014-01-01

    Environment monitoring is important for the safety of underground coal mine production, and it is also an important application of Wireless Sensor Networks (WSNs). We put forward an integrated environment monitoring system for underground coal mine, which uses the existing Cable Monitoring System (CMS) as the main body and the WSN with multi-parameter monitoring as the supplementary technique. As CMS techniques are mature, this paper mainly focuses on the WSN and the interconnection between t...

  5. Analysis of radio wave propagation for ISM 2.4 GHz Wireless Sensor Networks in inhomogeneous vegetation environments.

    Science.gov (United States)

    Azpilicueta, Leire; López-Iturri, Peio; Aguirre, Erik; Mateo, Ignacio; Astrain, José Javier; Villadangos, Jesús; Falcone, Francisco

    2014-12-10

    The use of wireless networks has experienced exponential growth due to the improvements in terms of battery life and low consumption of the devices. However, it is compulsory to conduct previous radio propagation analysis when deploying a wireless sensor network. These studies are necessary to perform an estimation of the range coverage, in order to optimize the distance between devices in an actual network deployment. In this work, the radio channel characterization for ISM 2.4 GHz Wireless Sensor Networks (WSNs) in an inhomogeneous vegetation environment has been analyzed. This analysis allows designing environment monitoring tools based on ZigBee and WiFi where WSN and smartphones cooperate, providing rich and customized monitoring information to users in a friendly manner. The impact of topology as well as morphology of the environment is assessed by means of an in-house developed 3D Ray Launching code, to emulate the realistic operation in the framework of the scenario. Experimental results gathered from a measurement campaign conducted by deploying a ZigBee Wireless Sensor Network, are analyzed and compared with simulations in this paper. The scenario where this network is intended to operate is a combination of buildings and diverse vegetation species. To gain insight in the effects of radio propagation, a simplified vegetation model has been developed, considering the material parameters and simplified geometry embedded in the simulation scenario. An initial location-based application has been implemented in a real scenario, to test the functionality within a context aware scenario. The use of deterministic tools can aid to know the impact of the topological influence in the deployment of the optimal Wireless Sensor Network in terms of capacity, coverage and energy consumption, making the use of these systems attractive for multiple applications in inhomogeneous vegetation environments.

  6. Analysis of Radio Wave Propagation for ISM 2.4 GHz Wireless Sensor Networks in Inhomogeneous Vegetation Environments

    Directory of Open Access Journals (Sweden)

    Leire Azpilicueta

    2014-12-01

    Full Text Available The use of wireless networks has experienced exponential growth due to the improvements in terms of battery life and low consumption of the devices. However, it is compulsory to conduct previous radio propagation analysis when deploying a wireless sensor network. These studies are necessary to perform an estimation of the range coverage, in order to optimize the distance between devices in an actual network deployment. In this work, the radio channel characterization for ISM 2.4 GHz Wireless Sensor Networks (WSNs in an inhomogeneous vegetation environment has been analyzed. This analysis allows designing environment monitoring tools based on ZigBee and WiFi where WSN and smartphones cooperate, providing rich and customized monitoring information to users in a friendly manner. The impact of topology as well as morphology of the environment is assessed by means of an in-house developed 3D Ray Launching code, to emulate the realistic operation in the framework of the scenario. Experimental results gathered from a measurement campaign conducted by deploying a ZigBee Wireless Sensor Network, are analyzed and compared with simulations in this paper. The scenario where this network is intended to operate is a combination of buildings and diverse vegetation species. To gain insight in the effects of radio propagation, a simplified vegetation model has been developed, considering the material parameters and simplified geometry embedded in the simulation scenario. An initial location-based application has been implemented in a real scenario, to test the functionality within a context aware scenario. The use of deterministic tools can aid to know the impact of the topological influence in the deployment of the optimal Wireless Sensor Network in terms of capacity, coverage and energy consumption, making the use of these systems attractive for multiple applications in inhomogeneous vegetation environments.

  7. Performance in wireless networks and industrial wireless networks on control processes in real time under industrial environments

    Directory of Open Access Journals (Sweden)

    Juan F. Monsalve-Posada

    2015-01-01

    Full Text Available The growing use of Ethernet networks on the industrial automation pyramid has led many companies to develop new devices to operate in requirements of this level, nowadays it is called Industrial Ethernet network, on the market there are various sensors and actuators to industrial scale equipped with this technology, many of these devices are very expensive. In this paper, the performance of two wireless networks is evaluated, the first network has conventional Ethernet devices, and the second network has Industrial Ethernet devices. For the process we vary four parameters such as distance, number of bytes, the signal to noise ratio, and the packet error rate, and then we measure delays and compare with metric statistics results, Box Plot graphs were used for the analysis. Finally, we conclude that under the parameters and conditions tested, wireless networks can serve as a communication system in control applications with allowable delays of up to 50 ms, in addition, the results show a better performance of Industrial Ethernet networks over conventional networks, with differences in the RTT of milliseconds. Therefore, it is recommended to establish what risk is for the process to control these delays to determine if the equipment conventional applies, since under certain features like humidity and temperature can operate properly for a considerable time and at lower cost than devices to Industrial Ethernet.

  8. Ship-to-Ship Radiocommunication Trial by Using Wireless LAN

    Directory of Open Access Journals (Sweden)

    Yasuyuki Niwa

    2015-12-01

    In a former field radiocommunication trial, omni-directional antennas were used and a few hundred kbps throughput between two ships was measured, which was not enough for our research target (over 1Mbps. In order to get faster throughput, a field radiocommunication trial was carried out again with a few types of directional antennas and RSSI (Received Signal Strength Indication and the throughput between two ships was measured simultaneously. As a result, multi-path (2-path model affected by the reflection of the sea surface was confirmed and also the characteristics of the directional antennas such as half-power angle were confirmed, but the measured throughput was fast enough to meet our expectation.

  9. ~ Effects of Data Frame Size Disbibution on Wireless LANS

    African Journals Online (AJOL)

    User

    back-off duration control frames (ACK) transmissions and even inter-frame spaces. This paper provides ... single Medium Access Control (MAC) and ... The rules of .... graph. Results of the three cases are shown below. DUAL FIXED CASE 1.

  10. Wireless Lan Network Security Method Wep (Wired Equivalent Privacy)

    OpenAIRE

    Ogy Charles Sario Tamawiwy; Nenny Anggraini, Skom., MT

    2008-01-01

    Scientific writing is about the WEP configuration on the WLAN network with RC4 encryption. The problem that arises is related aspects network security threats, strategic security and confidentiality of data in the network computer, the definition of encryption, definition kriptography algorithm, and algorithm functions.

  11. Effects of Data Frame Size Distribution on Wireless Lans | Aneke ...

    African Journals Online (AJOL)

    IEEE 802.11 WLAN is known to achieve relatively small throughput performance compared to the underlying physical layer's transmission rate and this is as a result of large overhead information composed of medium access control header, physical layer preamble information back-off duration control frames (ACK) ...

  12. Quantitative analysis of the security performance in wireless LANs

    Directory of Open Access Journals (Sweden)

    Poonam Jindal

    2017-07-01

    Full Text Available A comprehensive experimental study to analyze the security performance of a WLAN based on IEEE 802.11 b/g/n standards in various network scenarios is presented in this paper. By setting-up an experimental testbed we have measured results for a layered security model in terms of throughput, response time, encryption overheads, frame loss and jitter. Through numerical results obtained from the testbed, we have presented quantitative as well as realistic findings for both security mechanisms and network performance. It establishes the fact that there is always a tradeoff between the security strength and the associated network performance. It is observed that the non-roaming network always performs better than the roaming network under all network scenarios. To analyze the benefits offered by a particular security protocol a relative security strength index model is demonstrated. Further we have presented the statistical analysis of our experimental data. We found that different security protocols have different robustness against mobility. By choosing the robust security protocol, network performance can be improved. The presented analysis is significant and useful with reference to the assessment of the suitability of security protocols for given real time application.

  13. Wireless Adaptive Therapeutic TeleGaming in a Pervasive Computing Environment

    Science.gov (United States)

    Peters, James F.; Szturm, Tony; Borkowski, Maciej; Lockery, Dan; Ramanna, Sheela; Shay, Barbara

    This chapter introduces a wireless, pervasive computing approach to adaptive therapeutic telegaming considered in the context of near set theory. Near set theory provides a formal basis for observation, comparison and classification of perceptual granules. A perceptual granule is defined by a collection of objects that are graspable by the senses or by the mind. In the proposed pervasive computing approach to telegaming, a handicapped person (e.g., stroke patient with limited hand, finger, arm function) plays a video game by interacting with familiar instrumented objects such as cups, cutlery, soccer balls, nozzles, screw top-lids, spoons, so that the technology that makes therapeutic exercise game-playing possible is largely invisible (Archives of Physical Medicine and Rehabilitation 89:2213-2217, 2008). The basic approach to adaptive learning (AL) in the proposed telegaming environment is ethology-inspired and is quite different from the traditional approach to reinforcement learning. In biologically-inspired learning, organisms learn to achieve some goal by durable modification of behaviours in response to signals from the environment resulting from specific experiences (Animal Behavior, 1995). The term adaptive is used here in an ethological sense, where learning by an organism results from modifying behaviour in response to perceived changes in the environment. To instill adaptivity in a video game, it is assumed that learning by a video game is episodic. During an episode, the behaviour of a player is measured indirectly by tracking the occurrence of gaming events such as a hit or a miss of a target (e.g., hitting a moving ball with a game paddle). An ethogram provides a record of behaviour feature values that provide a basis a functional registry for handicapped players for gaming adaptivity. An important practical application of adaptive gaming is therapeutic rehabilitation exercise carried out in parallel with playing action video games. Enjoyable and

  14. Unmanned Aerial Vehicle Based Wireless Sensor Network for Marine-Coastal Environment Monitoring.

    Science.gov (United States)

    Trasviña-Moreno, Carlos A; Blasco, Rubén; Marco, Álvaro; Casas, Roberto; Trasviña-Castro, Armando

    2017-02-24

    Marine environments are delicate ecosystems which directly influence local climates, flora, fauna, and human activities. Their monitorization plays a key role in their preservation, which is most commonly done through the use of environmental sensing buoy networks. These devices transmit data by means of satellite communications or close-range base stations, which present several limitations and elevated infrastructure costs. Unmanned Aerial Vehicles (UAV) are another alternative for remote environmental monitoring which provide new types of data and ease of use. These aircraft are mainly used in video capture related applications, in its various light spectrums, and do not provide the same data as sensing buoys, nor can they be used for such extended periods of time. The aim of this research is to provide a flexible, easy to deploy and cost-effective Wireless Sensor Network (WSN) for monitoring marine environments. This proposal uses a UAV as a mobile data collector, low-power long-range communications and sensing buoys as part of a single WSN. A complete description of the design, development, and implementation of the various parts of this system is presented, as well as its validation in a real-world scenario.

  15. Integration of wireless sensor networks into cyberinfrastructure for monitoring Hawaiian "mountain-to-sea" environments.

    Science.gov (United States)

    Kido, Michael H; Mundt, Carsten W; Montgomery, Kevin N; Asquith, Adam; Goodale, David W; Kaneshiro, Kenneth Y

    2008-10-01

    Monitoring the complex environmental relationships and feedbacks of ecosystems on catchment (or mountain)-to-sea scales is essential for social systems to effectively deal with the escalating impacts of expanding human populations globally on watersheds. However, synthesis of emerging technologies into a robust observing platform for the monitoring of coupled human-natural environments on extended spatial scales has been slow to develop. For this purpose, the authors produced a new cyberinfrastructure for environmental monitoring which successfully merged the use of wireless sensor technologies, grid computing with three-dimensional (3D) geospatial data visualization/exploration, and a secured internet portal user interface, into a working prototype for monitoring mountain-to-sea environments in the high Hawaiian Islands. A use-case example is described in which native Hawaiian residents of Waipa Valley (Kauai) utilized the technology to monitor the effects of regional weather variation on surface water quality/quantity response, to better understand their local hydrologic cycle, monitor agricultural water use, and mitigate the effects of lowland flooding.

  16. LAN MAP: An Innovative Airborne Light at Night Mapping Project

    Science.gov (United States)

    Craine, Eric R.; Craine, B. L.; Craine, E. M.; Craine, P. R.

    2013-01-01

    Widespread installation of inefficient and misdirected artificial light at night (LAN) has led to increasing concerns about light pollution and its impact, not only on astronomical facilities but larger communities as well. Light pollution impacts scientific research, environmental ecosystems, human health, and quality of life. In recent years, the public policy response to light pollution has included formulation of government codes to regulate lighting design and installation. Various environmental groups now include light pollution among their rallying themes to protest both specific and general developments. The latter efforts are often conducted in the absence of any quantitative data and are frequently charged by emotion rather than reason. To bring some scientific objectivity, and quantitative data, to these discussions, we have developed a suite of tools for simultaneous photometric measurements and temporal monitoring of both local communities and the sky overhead. We have also developed novel protocols for the use of these tools, including a triad of airborne, ground mobile, and ground static photometric surveys. We present a summary of these tools and protocols, with special emphasis on the airborne systems, and discuss baseline and follow-up measurements of LAN environments in the vicinity of numerous observatories in Arizona, the home of the initial LAN MAP surveys.

  17. Implementation of mobile ip smooth handoff in wireless networks

    International Nuclear Information System (INIS)

    Kayastha, M.; Chowdhry, B.S.; Memon, A.R.

    2002-01-01

    This paper describes implementation of mobile IP services in two separate wireless LANs based on IEEE 802.11b standards, located in two distant buildings of a university campus. The purpose of the project was to achieve smooth hand-off when a mobile node moves between the two LANs. During our experimentation we have identified some of the limitation of IEEE 802.11b that affects mobile 1P smooth hand off. We have also proposed an algorithm to solve this problem when the mobility is within a limited number of separate wireless LANs. (author)

  18. Implementation of an Embedded Web Server Application for Wireless Control of Brain Computer Interface Based Home Environments.

    Science.gov (United States)

    Aydın, Eda Akman; Bay, Ömer Faruk; Güler, İnan

    2016-01-01

    Brain Computer Interface (BCI) based environment control systems could facilitate life of people with neuromuscular diseases, reduces dependence on their caregivers, and improves their quality of life. As well as easy usage, low-cost, and robust system performance, mobility is an important functionality expected from a practical BCI system in real life. In this study, in order to enhance users' mobility, we propose internet based wireless communication between BCI system and home environment. We designed and implemented a prototype of an embedded low-cost, low power, easy to use web server which is employed in internet based wireless control of a BCI based home environment. The embedded web server provides remote access to the environmental control module through BCI and web interfaces. While the proposed system offers to BCI users enhanced mobility, it also provides remote control of the home environment by caregivers as well as the individuals in initial stages of neuromuscular disease. The input of BCI system is P300 potentials. We used Region Based Paradigm (RBP) as stimulus interface. Performance of the BCI system is evaluated on data recorded from 8 non-disabled subjects. The experimental results indicate that the proposed web server enables internet based wireless control of electrical home appliances successfully through BCIs.

  19. OIT Wireless Telemetry for Industrial Applications

    Energy Technology Data Exchange (ETDEWEB)

    Manges, WW

    2002-09-03

    ability of wireless sensor networks to operate cooperatively in an environment that includes wireless LANs, wireless headsets, RF heating, wireless crane controls and many other users of the electromagnetic spectrum will probably be the most important issue we can address. A network of units (Figure 1) has been developed that demonstrates the feasibility of direct-sequence spread spectrum wireless sensor networking for industrial environments. The hardware consists of a group of reprogrammable transceivers that can act as sensor nodes or network nodes or both. These units and the team that built them are the heart of a test bed development system that has been used successfully in demonstrations at various industrial sites. As previously reported, these units have been successfully tested at a paper mill. More recently, these units were utilized in a permanent installation at a steel mill. Both of these applications demonstrated the ease with which a new network could be installed, and the reality that DSSS units can operate successfully in plants where narrow band transmitters had previously caused interference with plant operations.

  20. Wireless multipoint communication for optical sensors in the industrial environment using the new Bluetooth standard

    Science.gov (United States)

    Hussmann, Stephan; Lau, Wing Y.; Chu, Terry; Grothof, Markus

    2003-07-01

    Traditionally, the measuring or monitoring system of manufacturing industries uses sensors, computers and screens for their quality control (Q.C.). The acquired information is fed back to the control room by wires, which - for obvious reason - are not suitable in many environments. This paper describes a method to solve this problem by employing the new Bluetooth technology to set up a complete new system, where a total wireless solution is made feasible. This new Q.C. system allows several line scan cameras to be connected at once to a graphical user interface (GUI) that can monitor the production process. There are many Bluetooth devices available on the market such as cell-phones, headsets, printers, PDA etc. However, the detailed application is a novel implementation in the industrial Q.C. area. This paper will contain more details about the Bluetooth standard and why it is used (nework topologies, host controller interface, data rates, etc.), the Bluetooth implemetation in the microcontroller of the line scan camera, and the GUI and its features.

  1. Substrate Integrated Waveguide (SIW)-Based Wireless Temperature Sensor for Harsh Environments.

    Science.gov (United States)

    Tan, Qiulin; Guo, Yanjie; Zhang, Lei; Lu, Fei; Dong, Helei; Xiong, Jijun

    2018-05-03

    This paper presents a new wireless sensor structure based on a substrate integrated circular waveguide (SICW) for the temperature test in harsh environments. The sensor substrate material is 99% alumina ceramic, and the SICW structure is composed of upper and lower metal plates and a series of metal cylindrical sidewall vias. A rectangular aperture antenna integrated on the surface of the SICW resonator is used for electromagnetic wave transmission between the sensor and the external antenna. The resonant frequency of the temperature sensor decreases when the temperature increases, because the relative permittivity of the alumina ceramic increases with temperature. The temperature sensor presented in this paper was tested four times at a range of 30⁻1200 °C, and a broad band coplanar waveguide (CPW)-fed antenna was used as an interrogation antenna during the test process. The resonant frequency changed from 2.371 to 2.141 GHz as the temperature varied from 30 to 1200 °C, leading to a sensitivity of 0.197 MHz/°C. The quality factor of the sensor changed from 3444.6 to 35.028 when the temperature varied from 30 to 1000 °C.

  2. LAN attack detection using Discrete Event Systems.

    Science.gov (United States)

    Hubballi, Neminath; Biswas, Santosh; Roopa, S; Ratti, Ritesh; Nandi, Sukumar

    2011-01-01

    Address Resolution Protocol (ARP) is used for determining the link layer or Medium Access Control (MAC) address of a network host, given its Internet Layer (IP) or Network Layer address. ARP is a stateless protocol and any IP-MAC pairing sent by a host is accepted without verification. This weakness in the ARP may be exploited by malicious hosts in a Local Area Network (LAN) by spoofing IP-MAC pairs. Several schemes have been proposed in the literature to circumvent these attacks; however, these techniques either make IP-MAC pairing static, modify the existing ARP, patch operating systems of all the hosts etc. In this paper we propose a Discrete Event System (DES) approach for Intrusion Detection System (IDS) for LAN specific attacks which do not require any extra constraint like static IP-MAC, changing the ARP etc. A DES model is built for the LAN under both a normal and compromised (i.e., spoofed request/response) situation based on the sequences of ARP related packets. Sequences of ARP events in normal and spoofed scenarios are similar thereby rendering the same DES models for both the cases. To create different ARP events under normal and spoofed conditions the proposed technique uses active ARP probing. However, this probing adds extra ARP traffic in the LAN. Following that a DES detector is built to determine from observed ARP related events, whether the LAN is operating under a normal or compromised situation. The scheme also minimizes extra ARP traffic by probing the source IP-MAC pair of only those ARP packets which are yet to be determined as genuine/spoofed by the detector. Also, spoofed IP-MAC pairs determined by the detector are stored in tables to detect other LAN attacks triggered by spoofing namely, man-in-the-middle (MiTM), denial of service etc. The scheme is successfully validated in a test bed. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Study of RF Propagation Characteristics for Wireless Sensor Networks in Railroad Environments

    Science.gov (United States)

    2010-01-01

    The freight railroad industry in North America is exerting efforts to leverage Wireless Sensor Networks to monitor systems and components on railcars. This allows fault detection and accident prevention even while a train is moving. Railcars, constru...

  4. A Novel Energy-Aware Distributed Clustering Algorithm for Heterogeneous Wireless Sensor Networks in the Mobile Environment.

    Science.gov (United States)

    Gao, Ying; Wkram, Chris Hadri; Duan, Jiajie; Chou, Jarong

    2015-12-10

    In order to prolong the network lifetime, energy-efficient protocols adapted to the features of wireless sensor networks should be used. This paper explores in depth the nature of heterogeneous wireless sensor networks, and finally proposes an algorithm to address the problem of finding an effective pathway for heterogeneous clustering energy. The proposed algorithm implements cluster head selection according to the degree of energy attenuation during the network's running and the degree of candidate nodes' effective coverage on the whole network, so as to obtain an even energy consumption over the whole network for the situation with high degree of coverage. Simulation results show that the proposed clustering protocol has better adaptability to heterogeneous environments than existing clustering algorithms in prolonging the network lifetime.

  5. Spread Spectrum Techniques and their Applications to Wireless Communications

    DEFF Research Database (Denmark)

    Prasad, Ramjee; Cianca, E.

    2005-01-01

    Spread Spectrum (SS) radio communications is on the verge of potentially explosive commercial development An SS-based multiple access, such as CDMA, has been chosen for 3G wireless communications. Other current applications of SS techniues are in Wireless LANs and Satellite Navigation Systems...

  6. Wireless local area network. A new technology of network

    International Nuclear Information System (INIS)

    Wu Yunjun; Zhao Zongtao

    2003-01-01

    This paper introduces Wireless Local Area Network (WLAN), including the concept, history, characters and the foreground of its development, it also narrates in detail the several key techniques used to implement IEEE802.11 WLAN, and ideas on key technology of future progress in wireless LAN field have also been presented. (authors)

  7. Makna ‘Seneng lan Kemringet’ dalam Festival Lima Gunung

    Directory of Open Access Journals (Sweden)

    joko aswoyo

    2018-04-01

    ABSTRAK Artikel ini bertujuan untuk mengetahui makna ungkapan ‘seneng lan kemringet’ pada Festival Lima Gunung (FLG di Magelang. Ungkapan ‘seneng lan kemringet’ memberi kesempatan bagi yang terlibat untuk mengungkapkan keberadaannya dan berbicara tentang hakikat dirinya. Dengan keakraban, keterlibatan langsung dalam aktivitas kesenian, dan berdialog dengan petani atas kenyataan-kenyataan di lapangan, akan dapat disingkap makna di balik ungkapan ‘seneng lan kemringet’ tersebut. Hasil dari penelitian kami menunjukkan bahwa di dalam ungkapan ‘seneng lan kemringet’ tersimpan daya hidup sebagai modal dasar keberlanjutan FLG. ‘Seneng lan kemringet’ juga dimaknai sebagai otonomi dan aktualisasidiri. Selain itu, ‘seneng lan kemringet’ adalah bagian dari permainan dengan tujuan untuk memperlihatkan eksistensi diri. Pada akhirnya, ‘seneng lan kemringet’ merupakan kebanggaan diri. Kata kunci: ‘seneng lan kemringet’, daya hidup, dan permainan

  8. Construction of the NIFS campus information network, NIFS-LAN

    Energy Technology Data Exchange (ETDEWEB)

    Tsuda, Kenzo; Yamamoto, Takashi; Kato, Takeo; Nakamura, Osamu; Watanabe, Kunihiko; Watanabe, Reiko; Tsugawa, Kazuko; Kamimura, Tetsuo

    2000-10-01

    The advanced NIFS campus information network, NIFS-LAN, was designed and constructed as an informational infrastructure in 1996, 1997 and 1998 fiscal year. NIFS-LAN was composed of three autonomous clusters classified from research purpose; Research Information cluster, Large Helical Device Experiment cluster and Large-Scale Computer Simulation Research cluster. Many ATM(Asychronous Transfer Mode) switching systems and switching equipments were used for NIFS-LAN. Here, the outline of NIFS-LAN is described. (author)

  9. Cross-layer based adaptive wireless traffic control for per-flow and per-station fairness

    Directory of Open Access Journals (Sweden)

    Siwamogsatham Siwaruk

    2011-01-01

    Full Text Available Abstract In the IEEE 802.11 wireless LANs, the bandwidth is not fairly shared among stations due to the distributed coordination function (DCF mechanism in the IEEE 802.11 MAC protocol. It introduces the per-flow and per-station unfairness problems between uplink and downlink flows, as the uplink flows usually dominate the downlink flows. In addition, some users may use greedy applications such as video streaming, which may prevent other applications from connecting to the Internet. In this article, we propose an adaptive cross-layer bandwidth allocation mechanism to provide per-station and per-flow fairness. To verify the effectiveness and scalability, our scheme is implemented on a wireless access router and numerous experiments in a typical wireless environment with both TCP and UDP traffic are conducted to evaluate performance of the proposed scheme.

  10. Obituary: Howard H. Lanning, 1946-2007

    Science.gov (United States)

    Wade, Richard A.; MacConnell, D. Jack

    2009-01-01

    Howard H. Lanning died 20 December 2007 in Tucson, Arizona. He was a Software Quality Assurance Engineer for the Data Products Program at the National Optical Astronomy Observatory [NOAO] in Tucson, having returned to his native West after twenty years at the Space Telescope Science Institute [STScI] in Baltimore, Maryland. Throughout his career in roles supporting other astronomers, Howard steadily and persistently worked at his own research programs, most notably the identification and study of UV-bright sources in the Sandage Two-Color Survey of the Galactic Plane. Minor planet 2000 QJ248 has been named (61913) Lanning in recognition of his contributions. The son of James Clyde Lanning and Ethel Malan Lanning, Howard was born 26 May 1946, in Brawley, a small community near Calipatria, California. His parents worked for the local school district where his late father was Superintendent of Maintenance and Grounds and his mother was a school principal. After graduating from high school in a class of 52, Howard earned his A.A. degree at Imperial Valley Junior College, majoring in Astronomy and minoring in Mathematics. He completed his A.B. degree in Applied Arts and Sciences at San Diego State University [SDSU] in 1969 with the same major and minor. In 1974, he completed his M.S. in Astronomy at SDSU with a thesis on the period variation of the white-dwarf eclipsing binary BD +16∘516. During his time at SDSU Lanning was a Research Assistant/Observer at the former Hale Observatories, working on the optical identification of X-ray sources under the direction of Allan Sandage. His second refereed paper, the first of several finding lists of UV-bright stars arising from this work, appeared in 1973. Fellow students and faculty remember that he was a self-starter, initiating many observing projects of his own at Mount Laguna Observatory and encouraging others to do the same. For more than a decade Lanning was an observer and night assistant at Mount Wilson Observatory

  11. Towards adaptive security for convergent wireless sensor networks in beyond 3G environments

    DEFF Research Database (Denmark)

    Mitseva, Anelia; Aivaloglou, Efthimia; Marchitti, Maria-Antonietta

    2010-01-01

    The integration of wireless sensor networks with different network systems gives rise to many research challenges to ensure security, privacy and trust in the overall architecture. The main contribution of this paper is a generic security, privacy and trust framework providing context-aware adapt...

  12. Migration of TCP Connections with Layer-2 Support in Wireless Environments

    NARCIS (Netherlands)

    Bosch, H.G.P.; Cortes, Mauricio; Janiszewski, Tom J.; McKie, Jim B.; Mullender, Sape J.; Rajkumar, Ajay; Recchione, Michael C.; Rossetti, David A.; Turner, Michael D.

    2008-01-01

    Example embodiments provide methods of transparently migrating a reliable transport layer connection between a user and a first base station and a second base station in a wireless network. The method includes receiving at least one transport layer connection state information parameter from the

  13. Integrating wireless sensor networks with CE devices for health care activity tracking in the home environment

    NARCIS (Netherlands)

    Bosman, R.P.; Lukkien, J.J.; Verhoeven, R.

    2009-01-01

    Wireless sensing devices containing limited processing and communication capabilities are becoming available for all sorts of purposes. An important problem is to integrate networks of these sensors with the existing CE en IT infrastructure such that a) data coming out of the sensor network can be

  14. Heterogeneous tiny energy: An appealing opportunity to power wireless sensor motes in a corrosive environment

    International Nuclear Information System (INIS)

    Qiao, Guofu; Sun, Guodong; Li, Hui; Ou, Jinping

    2014-01-01

    Highlights: • Ultra-low ambient energy was scavenged to power the first of its kind wireless corrosion sensors. • Three feasible tiny-energy sources were exploited for long-term corrosion monitoring. • Automatic recharging control of heterogeneous tiny energy was proposed for human-free monitoring. • Corrosion itself was applied as an energy source to power the wireless corrosion-monitoring motes. - Abstract: Reinforcing steel corrosion is a significant factor leading to the durability deterioration of reinforced concrete (RC) structures. The on-line monitoring of the corrosion of RC structures in a long-term, human-free manner is not only valuable in industry, but also a significant challenge in academia. This paper presents the first of its kind corrosion-monitoring approach that only exploits three heterogeneous tiny energy sources to power commercial-off-the-shelf wireless sensor motes such that the corrosion-related data are automatically and autonomously captured and sent to users via wireless channels. We first investigated the availability of these three tiny energy sources: corrosion energy, a cement battery, and a weak solar energy. In particular, the two former energy sources inherently exist in RC structures and can be generated continually in the service-life of RC structures, which beneficial for the prospects of long-term corrosion monitoring. We then proposed a proof-of-concept prototype, which consisted of a Telosb wireless sensor mote and an energy harvester in order to evaluate the feasibility and effectiveness of the ultralow-power ambient energy as a type of power supply in corrosion monitoring applications. The critical metrics for the holographic monitoring of RC structures, including electrochemical noise, humidity and temperature, were successfully acquired and analysed using a post-processing program. This paper describes a unique and novel approach towards the realisation of smart structural monitoring and control system in the

  15. Development and Application of a Wireless Sensor for Space Charge Density Measurement in an Ultra-High-Voltage, Direct-Current Environment.

    Science.gov (United States)

    Xin, Encheng; Ju, Yong; Yuan, Haiwen

    2016-10-20

    A space charge density wireless measurement system based on the idea of distributed measurement is proposed for collecting and monitoring the space charge density in an ultra-high-voltage direct-current (UHVDC) environment. The proposed system architecture is composed of a number of wireless nodes connected with space charge density sensors and a base station. The space charge density sensor based on atmospheric ion counter method is elaborated and developed, and the ARM microprocessor and Zigbee radio frequency module are applied. The wireless network communication quality and the relationship between energy consumption and transmission distance in the complicated electromagnetic environment is tested. Based on the experimental results, the proposed measurement system demonstrates that it can adapt to the complex electromagnetic environment under the UHVDC transmission lines and can accurately measure the space charge density.

  16. Access Protocol For An Industrial Optical Fibre LAN

    Science.gov (United States)

    Senior, John M.; Walker, William M.; Ryley, Alan

    1987-09-01

    A structure for OSI levels 1 and 2 of a local area network suitable for use in a variety of industrial environments is reported. It is intended that the LAN will utilise optical fibre technology at the physical level and a hybrid of dynamically optimisable token passing and CSMA/CD techniques at the data link (IEEE 802 medium access control - logical link control) level. An intelligent token passing algorithm is employed which dynamically allocates tokens according to the known upper limits on the requirements of each device. In addition a system of stochastic tokens is used to increase efficiency when the stochastic traffic is significant. The protocol also allows user-defined priority systems to be employed and is suitable for distributed or centralised implementation. The results of computer simulated performance characteristics for the protocol using a star-ring topology are reported which demonstrate its ability to perform efficiently with the device and traffic loads anticipated within an industrial environment.

  17. Field measurements and guidelines for the application of wireless sensor networks to the environment and security.

    Science.gov (United States)

    Gil Jiménez, Víctor P; Armada, Ana García

    2009-01-01

    Frequently, Wireless Sensor Networks (WSN) are designed focusing on applications and omitting transmission problems in these wireless networks. In this paper, we present a measurement campaign that has been carried out using one of the most commonly used WSN platforms, the micaZ from Crossbow(©). Based on these measurements, some guidelines to deploy a robust and reliable WSN are provided. The results are focused on security and environmental applications but can also be extrapolated to other scenarios. A main conclusion that can be extracted is that, from the transmission point of view, a dense WSN is one of the best choices to overcome many of the transmission problems such as the existence of a transitional region, redundance, forwarding, obstructions or interference with other systems.

  18. Remote Monitoring of Post-eruption Volcano Environment Based-On Wireless Sensor Network (WSN): The Mount Sinabung Case

    Science.gov (United States)

    Soeharwinto; Sinulingga, Emerson; Siregar, Baihaqi

    2017-01-01

    An accurate information can be useful for authorities to make good policies for preventive and mitigation after volcano eruption disaster. Monitoring of environmental parameters of post-eruption volcano provides an important information for authorities. Such monitoring system can be develop using the Wireless Network Sensor technology. Many application has been developed using the Wireless Sensor Network technology, such as floods early warning system, sun radiation mapping, and watershed monitoring. This paper describes the implementation of a remote environment monitoring system of mount Sinabung post-eruption. The system monitor three environmental parameters: soil condition, water quality and air quality (outdoor). Motes equipped with proper sensors, as components of the monitoring system placed in sample locations. The measured value from the sensors periodically sends to data server using 3G/GPRS communication module. The data can be downloaded by the user for further analysis.The measurement and data analysis results generally indicate that the environmental parameters in the range of normal/standard condition. The sample locations are safe for living and suitable for cultivation, but awareness is strictly required due to the uncertainty of Sinabung status.

  19. Thermomechanical stability and integrability of an embedded ceramic antenna with an integrated sensor element for wireless reading in harsh environments

    Science.gov (United States)

    Sturesson, P.; Khaji, Z.; Knaust, S.; Sundqvist, J.; Klintberg, L.; Thornell, G.

    2013-12-01

    This paper reports on the design, manufacturing and evaluation of a small, wirelessly powered and read resonating antenna circuit with an integrated pressure sensor. The work aims at developing miniature devices suitable for harsh environments, where high temperature prevents the use of conventional, silicon-based microdevices. Here, the device is made of alumina with platinum as conducting material. Ceramic green tapes were structured using high-precision milling, metallized using screen printing, and subsequently laminated to form stacks before they were sintered. The device's frequency shift as a function of temperature was studied up to 900°C. The contributions to the shift both from the thermomechanical deformation of the device at large, and from the integrated and, so far, self-pressurized sensor were sorted out. A total frequency shift of 3200 ppm was observed for the pressure sensor for heating over the whole range. Negligible levels of thermally induced radius of curvature were observed. With three-point bending, a frequency shift of 180 ppm was possible to induce with a curvature of radius of 220 m at a 10 N load. The results indicate that a robust pressure sensor node, which can register pressure changes of a few bars at 900°C and wirelessly transmit the signal, is viable.

  20. Thermomechanical stability and integrability of an embedded ceramic antenna with an integrated sensor element for wireless reading in harsh environments

    International Nuclear Information System (INIS)

    Sturesson, P; Sundqvist, J; Thornell, G; Khaji, Z; Knaust, S; Klintberg, L

    2013-01-01

    This paper reports on the design, manufacturing and evaluation of a small, wirelessly powered and read resonating antenna circuit with an integrated pressure sensor. The work aims at developing miniature devices suitable for harsh environments, where high temperature prevents the use of conventional, silicon-based microdevices. Here, the device is made of alumina with platinum as conducting material. Ceramic green tapes were structured using high-precision milling, metallized using screen printing, and subsequently laminated to form stacks before they were sintered. The device's frequency shift as a function of temperature was studied up to 900°C. The contributions to the shift both from the thermomechanical deformation of the device at large, and from the integrated and, so far, self-pressurized sensor were sorted out. A total frequency shift of 3200 ppm was observed for the pressure sensor for heating over the whole range. Negligible levels of thermally induced radius of curvature were observed. With three-point bending, a frequency shift of 180 ppm was possible to induce with a curvature of radius of 220 m at a 10 N load. The results indicate that a robust pressure sensor node, which can register pressure changes of a few bars at 900°C and wirelessly transmit the signal, is viable

  1. Extending Wireless Broadband Network Architectures with Home Gateways, Localization, and Physical Environment Surveillance

    DEFF Research Database (Denmark)

    Jelling Kristoffersen, Kåre; Kjærgaard, Mikkel Baun; Chen, Jianjun

    2005-01-01

    homes. It must bridge across the most prevalent standard protocols for data, video, telephony and telemetry, and must be able to automatically discover new devices in a residence and allow over the air/wire provisioning, billing, management and aggregation of new services from multiple service providers...... is initially demonstrated in a 52 DECT base station installation covering four office buildings of total 4500 m2 . Finally the paper proposes the application of a commercial off-the-shelf wireless broadband network as a sensor network, without any additional hardware, for physical intrusion detection of e...

  2. Adaptive Multi-Layered Space-Time Block Coded Systems in Wireless Environments

    KAUST Repository

    Al-Ghadhban, Samir

    2014-12-23

    © 2014, Springer Science+Business Media New York. Multi-layered space-time block coded systems (MLSTBC) strike a balance between spatial multiplexing and transmit diversity. In this paper, we analyze the block error rate performance of MLSTBC. In addition, we propose an adaptive MLSTBC schemes that are capable of accommodating the channel signal-to-noise ratio variation of wireless systems by near instantaneously adapting the uplink transmission configuration. The main results demonstrate that significant effective throughput improvements can be achieved while maintaining a certain target bit error rate.

  3. Perancangan dan Simulasi Security LAN dengan Perangkat Cisco

    OpenAIRE

    Asma, Nur

    2015-01-01

    Perancangan ini dikembangkan dengan menggunakan perangkat lunak CISCO paket tracer. Biasanya dalam satu gedung fakultas mahasiswa berada dalam satu LAN sedangkan komputer dosen berada pada LAN lain. Hal ini sepertinya sudah sewajarna terjadi mengingat keadaan jaringan yang terhubung secara fisik. Jadi tujuan perancangan ini adalah membangun sistem keamanan LAN dengan sistem VLAN dan dijalankan dengan perangkat CISCO dari paket tracer. VLAN (Virtual Local Area Network) merupakan salah satu tek...

  4. 9 Office of Regions and Center Operations LANS -

    Data.gov (United States)

    Department of Transportation — The 9 Office of Regions and Center Operations LANS located at regional offices is the backbone that provides connectivity to systems including servers, workstations,...

  5. A wireless sensor enabled by wireless power.

    Science.gov (United States)

    Lee, Da-Sheng; Liu, Yu-Hong; Lin, Chii-Ruey

    2012-11-22

    Through harvesting energy by wireless charging and delivering data by wireless communication, this study proposes the concept of a wireless sensor enabled by wireless power (WPWS) and reports the fabrication of a prototype for functional tests. One WPWS node consists of wireless power module and sensor module with different chip-type sensors. Its main feature is the dual antenna structure. Following RFID system architecture, a power harvesting antenna was designed to gather power from a standard reader working in the 915 MHz band. Referring to the Modbus protocol, the other wireless communication antenna was integrated on a node to send sensor data in parallel. The dual antenna structure integrates both the advantages of an RFID system and a wireless sensor. Using a standard UHF RFID reader, WPWS can be enabled in a distributed area with a diameter up to 4 m. Working status is similar to that of a passive tag, except that a tag can only be queried statically, while the WPWS can send dynamic data from the sensors. The function is the same as a wireless sensor node. Different WPWSs equipped with temperature and humidity, optical and airflow velocity sensors are tested in this study. All sensors can send back detection data within 8 s. The accuracy is within 8% deviation compared with laboratory equipment. A wireless sensor network enabled by wireless power should be a totally wireless sensor network using WPWS. However, distributed WPWSs only can form a star topology, the simplest topology for constructing a sensor network. Because of shielding effects, it is difficult to apply other complex topologies. Despite this limitation, WPWS still can be used to extend sensor network applications in hazardous environments. Further research is needed to improve WPWS to realize a totally wireless sensor network.

  6. Wireless smart meters and public acceptance: the environment, limited choices, and precautionary politics.

    Science.gov (United States)

    Hess, David J; Coley, Jonathan S

    2014-08-01

    Wireless smart meters (WSMs) promise numerous environmental benefits, but they have been installed without full consideration of public acceptance issues. Although societal-implications research and regulatory policy have focused on privacy, security, and accuracy issues, our research indicates that health concerns have played an important role in the public policy debates that have emerged in California. Regulatory bodies do not recognize non-thermal health effects for non-ionizing electromagnetic radiation, but both homeowners and counter-experts have contested the official assurances that WSMs pose no health risks. Similarities and differences with the existing social science literature on mobile phone masts are discussed, as are the broader political implications of framing an alternative policy based on an opt-out choice. The research suggests conditions under which health-oriented precautionary politics can be particularly effective, namely, if there is a mandatory technology, a network of counter-experts, and a broader context of democratic contestation.

  7. An integrated environment monitoring system for underground coal mines--Wireless Sensor Network subsystem with multi-parameter monitoring.

    Science.gov (United States)

    Zhang, Yu; Yang, Wei; Han, Dongsheng; Kim, Young-Il

    2014-07-21

    Environment monitoring is important for the safety of underground coal mine production, and it is also an important application of Wireless Sensor Networks (WSNs). We put forward an integrated environment monitoring system for underground coal mine, which uses the existing Cable Monitoring System (CMS) as the main body and the WSN with multi-parameter monitoring as the supplementary technique. As CMS techniques are mature, this paper mainly focuses on the WSN and the interconnection between the WSN and the CMS. In order to implement the WSN for underground coal mines, two work modes are designed: periodic inspection and interrupt service; the relevant supporting technologies, such as routing mechanism, collision avoidance, data aggregation, interconnection with the CMS, etc., are proposed and analyzed. As WSN nodes are limited in energy supply, calculation and processing power, an integrated network management scheme is designed in four aspects, i.e., topology management, location management, energy management and fault management. Experiments were carried out both in a laboratory and in a real underground coal mine. The test results indicate that the proposed integrated environment monitoring system for underground coal mines is feasible and all designs performed well as expected.

  8. An Integrated Environment Monitoring System for Underground Coal Mines—Wireless Sensor Network Subsystem with Multi-Parameter Monitoring

    Science.gov (United States)

    Zhang, Yu; Yang, Wei; Han, Dongsheng; Kim, Young-Il

    2014-01-01

    Environment monitoring is important for the safety of underground coal mine production, and it is also an important application of Wireless Sensor Networks (WSNs). We put forward an integrated environment monitoring system for underground coal mine, which uses the existing Cable Monitoring System (CMS) as the main body and the WSN with multi-parameter monitoring as the supplementary technique. As CMS techniques are mature, this paper mainly focuses on the WSN and the interconnection between the WSN and the CMS. In order to implement the WSN for underground coal mines, two work modes are designed: periodic inspection and interrupt service; the relevant supporting technologies, such as routing mechanism, collision avoidance, data aggregation, interconnection with the CMS, etc., are proposed and analyzed. As WSN nodes are limited in energy supply, calculation and processing power, an integrated network management scheme is designed in four aspects, i.e., topology management, location management, energy management and fault management. Experiments were carried out both in a laboratory and in a real underground coal mine. The test results indicate that the proposed integrated environment monitoring system for underground coal mines is feasible and all designs performed well as expected. PMID:25051037

  9. An Integrated Environment Monitoring System for Underground Coal Mines—Wireless Sensor Network Subsystem with Multi-Parameter Monitoring

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    2014-07-01

    Full Text Available Environment monitoring is important for the safety of underground coal mine production, and it is also an important application of Wireless Sensor Networks (WSNs. We put forward an integrated environment monitoring system for underground coal mine, which uses the existing Cable Monitoring System (CMS as the main body and the WSN with multi-parameter monitoring as the supplementary technique. As CMS techniques are mature, this paper mainly focuses on the WSN and the interconnection between the WSN and the CMS. In order to implement the WSN for underground coal mines, two work modes are designed: periodic inspection and interrupt service; the relevant supporting technologies, such as routing mechanism, collision avoidance, data aggregation, interconnection with the CMS, etc., are proposed and analyzed. As WSN nodes are limited in energy supply, calculation and processing power, an integrated network management scheme is designed in four aspects, i.e., topology management, location management, energy management and fault management. Experiments were carried out both in a laboratory and in a real underground coal mine. The test results indicate that the proposed integrated environment monitoring system for underground coal mines is feasible and all designs performed well as expected.

  10. Performance Analysis of IEEE 802.15.4 Compliant Wireless Devices for Heterogeneous Indoor Home Automation Environments

    Directory of Open Access Journals (Sweden)

    Juan Antonio Nazabal

    2012-01-01

    Full Text Available The influence of topology as well as morphology of complex indoor scenarios in the deployment of wireless sensor networks and wireless systems applied to home and building automation systems is analyzed. The existence of loss mechanisms such as material absorption (walls, furniture, etc. and strong multipath components as well as the increase in the number of wireless sensors within indoor scenarios increases the relevance in the configuration of the heterogeneous wireless systems. Simulation results by means of empirical-based models are compared with an in-house 3D ray launching code as well as measurement results from wireless sensor networks illustrate the strong influence of the indoor scenario in the overall performance. The use of adequate radioplanning strategies lead to optimal wireless network deployments in terms of capacity, quality of service, and reduced power consumption.

  11. Channel Measurements and Modeling at 6 GHz in the Tunnel Environments for 5G Wireless Systems

    Directory of Open Access Journals (Sweden)

    Shuang-de Li

    2017-01-01

    Full Text Available Propagation measurements of wireless channels performed in the tunnel environments at 6 GHz are presented in this paper. Propagation characteristics are simulated and analyzed based on the method of shooting and bouncing ray tracing/image (SBR/IM. A good agreement is achieved between the measured results and simulated results, so the correctness of SBR/IM method has been validated. The measured results and simulated results are analyzed in terms of path loss models, received power, root mean square (RMS delay spread, Ricean K-factor, and angle of arrival (AOA. The omnidirectional path loss models are characterized based on close-in (CI free-space reference distance model and the alpha-beta-gamma (ABG model. Path loss exponents (PLEs are 1.50–1.74 in line-of-sight (LOS scenarios and 2.18–2.20 in non-line-of-sight (NLOS scenarios. Results show that CI model with the reference distance of 1 m provides more accuracy and stability in tunnel scenarios. The RMS delay spread values vary between 2.77 ns and 18.76 ns. Specially, the Poisson distribution best fits the measured data of RMS delay spreads for LOS scenarios and the Gaussian distribution best fits the measured data of RMS delay spreads for NLOS scenarios. Moreover, the normal distribution provides good fits to the Ricean K-factor. The analysis of the abovementioned results from channel measurements and simulations may be utilized for the design of wireless communications of future 5G radio systems at 6 GHz.

  12. SoundProof: A Smartphone Platform for Wireless Monitoring of Wildlife and Environment

    Science.gov (United States)

    Lukac, M.; Monibi, M.; Lane, M. L.; Howell, L.; Ramanathan, N.; Borker, A.; McKown, M.; Croll, D.; Terschy, B.

    2011-12-01

    We are developing an open-source, low-cost wildlife and environmental monitoring solution based on Android smartphones. Using a smartphone instead of a traditional microcontroller or single board computer has several advantages: smartphones are single integrated devices with multiple radios and a battery; they have a robust software interface which enables customization; and are field-tested by millions of users daily. Consequently, smartphones can improve the cost, configurability, and real-time access to data for environmental monitoring, ultimately replacing existing monitoring solutions which are proprietary, difficult to customize, expensive, and require labor-intensive maintenance. While smartphones can radically change environmental and wildlife monitoring, there are a number of technical challenges to address. We present our smartphone-based platform, SoundProof, discuss the challenges of building an autonomous system based on Android phones, and our ongoing efforts to enable environmental monitoring. Our system is built using robust off-the-shelf hardware and mature open-source software where available, to increase scalability and ease of installation. Key features include: * High-quality acoustic signal collection from external microphones to monitor wildlife populations. * Real-time data access, remote programming, and configuration of the field sensor via wireless cellular or WiFi channels, accessible from a website. * Waterproof packaging and solar charger setup for long-term field deployments. * Rich instrumentation of the end-to-end system to quickly identify and debug problems. * Supplementary mesh networking system with long-range wireless antennae to provide coverage when no cell network is available. We have deployed this system to monitor Rufous Crowned Sparrows on Anacapa Island, Chinese Crested Turns on the Matsu Islands in Taiwan, and Ashy Storm Petrels on South East Farallon Island. We have testbeds at two UC Natural Reserves to field

  13. Applying an intelligent and automated emissions measurement system to characterize the RF environment for supporting wireless technologies

    International Nuclear Information System (INIS)

    Keebler, P. F.; Phipps, K. O.

    2006-01-01

    The use of wireless technologies in commercial and industrial facilities has grown significantly in the past several years. New applications of wireless technologies with increasing frequency and varying radiated power are being developed everyday. Wireless application specialists and end users have already identified several sources of electromagnetic interference (EMI) in these facilities. Interference has been reported between wireless devices and between these devices and other types of electronic equipment either using frequencies in the unlicensed wireless spectrum or equipment that may generate undesired man-made noise in this spectrum. Facilities that are not using the wireless band should verify the spectral quality of that band and the electromagnetic compatibility (EMC) integrity of safety-related power and signal cables before installing wireless technologies. With the introduction of new wireless devices in the same electromagnetic space where analog and digital I and C systems and cables must co-exist, the ability of facility managers to manage their spectra will dictate the degree of interference between wireless devices and other electronic equipment. Because of the unknowns associated with interference with analog and digital I and C systems in the wireless band, nuclear power plants have been slow to introduce wireless technologies in plant areas. With the application of newly developed advanced radiated emissions measurement systems that can record, process, and analyze radiated and conducted emissions in a cost-effective manner, facility managers can more reliably characterize potential locations for wireless technologies, including potential coupling effects with safety-related power and signal cables, with increased confidence that the risks associated with creating an interference can be significantly reduced. This paper will present an effective philosophy already being used in other mission-critical applications for managing EMC, an

  14. Phase Clustering Based Modulation Classification Algorithm for PSK Signal over Wireless Environment

    Directory of Open Access Journals (Sweden)

    Qi An

    2016-01-01

    Full Text Available Promptitude and accuracy of signals’ non-data-aided (NDA identification is one of the key technology demands in noncooperative wireless communication network, especially in information monitoring and other electronic warfare. Based on this background, this paper proposes a new signal classifier for phase shift keying (PSK signals. The periodicity of signal’s phase is utilized as the assorted character, with which a fractional function is constituted for phase clustering. Classification and the modulation order of intercepted signals can be achieved through its Fast Fourier Transform (FFT of the phase clustering function. Frequency offset is also considered for practical conditions. The accuracy of frequency offset estimation has a direct impact on its correction. Thus, a feasible solution is supplied. In this paper, an advanced estimator is proposed for estimating the frequency offset and balancing estimation accuracy and range under low signal-to-noise ratio (SNR conditions. The influence on estimation range brought by the maximum correlation interval is removed through the differential operation of the autocorrelation of the normalized baseband signal raised to the power of Q. Then, a weighted summation is adopted for an effective frequency estimation. Details of equations and relevant simulations are subsequently presented. The estimator proposed can reach an estimation accuracy of 10-4 even when the SNR is as low as -15 dB. Analytical formulas are expressed, and the corresponding simulations illustrate that the classifier proposed is more efficient than its counterparts even at low SNRs.

  15. Motion-related resource allocation in dynamic wireless visual sensor network environments.

    Science.gov (United States)

    Katsenou, Angeliki V; Kondi, Lisimachos P; Parsopoulos, Konstantinos E

    2014-01-01

    This paper investigates quality-driven cross-layer optimization for resource allocation in direct sequence code division multiple access wireless visual sensor networks. We consider a single-hop network topology, where each sensor transmits directly to a centralized control unit (CCU) that manages the available network resources. Our aim is to enable the CCU to jointly allocate the transmission power and source-channel coding rates for each node, under four different quality-driven criteria that take into consideration the varying motion characteristics of each recorded video. For this purpose, we studied two approaches with a different tradeoff of quality and complexity. The first one allocates the resources individually for each sensor, whereas the second clusters them according to the recorded level of motion. In order to address the dynamic nature of the recorded scenery and re-allocate the resources whenever it is dictated by the changes in the amount of motion in the scenery, we propose a mechanism based on the particle swarm optimization algorithm, combined with two restarting schemes that either exploit the previously determined resource allocation or conduct a rough estimation of it. Experimental simulations demonstrate the efficiency of the proposed approaches.

  16. Wireless local network architecture for Naval medical treatment facilities

    OpenAIRE

    Deason, Russell C.

    2004-01-01

    Approved for public release; distribution is unlimited In today's Navy Medicine, an approach towards wireless networks is coming into view. The idea of developing and deploying workable Wireless Local Area Networks (WLAN) throughout Naval hospitals is but just a few years down the road. Currently Naval Medical Treatment Facilities (MTF) are using wired Local Area Networks (LANs) throughout the infrastructure of each facility. Civilian hospitals and other medical treatment facilities have b...

  17. Experience of wireless local area network in a radiation oncology department.

    Science.gov (United States)

    Mandal, Abhijit; Asthana, Anupam Kumar; Aggarwal, Lalit Mohan

    2010-01-01

    The aim of this work is to develop a wireless local area network (LAN) between different types of users (Radiation Oncologists, Radiological Physicists, Radiation Technologists, etc) for efficient patient data management and to made easy the availability of information (chair side) to improve the quality of patient care in Radiation Oncology department. We have used mobile workstations (Laptops) and stationary workstations, all equipped with wireless-fidelity (Wi-Fi) access. Wireless standard 802.11g (as recommended by Institute of Electrical and Electronic Engineers (IEEE, Piscataway, NJ) has been used. The wireless networking was configured with the Service Set Identifier (SSID), Media Access Control (MAC) address filtering, and Wired Equivalent Privacy (WEP) network securities. We are successfully using this wireless network in sharing the indigenously developed patient information management software. The proper selection of the hardware and the software combined with a secure wireless LAN setup will lead to a more efficient and productive radiation oncology department.

  18. Using OpenSSH to secure mobile LAN network traffic

    Science.gov (United States)

    Luu, Brian B.; Gopaul, Richard D.

    2002-08-01

    Mobile Internet Protocol (IP) Local Area Network (LAN) is a technique, developed by the U.S. Army Research Laboratory, which allows a LAN to be IP mobile when attaching to a foreign IP-based network and using this network as a means to retain connectivity to its home network. In this paper, we describe a technique that uses Open Secure Shell (OpenSSH) software to ensure secure, encrypted transmission of a mobile LAN's network traffic. Whenever a mobile LAN, implemented with Mobile IP LAN, moves to a foreign network, its gateway (router) obtains an IP address from the new network. IP tunnels, using IP encapsulation, are then established from the gateway through the foreign network to a home agent on its home network. These tunnels provide a virtual two-way connection to the home network for the mobile LAN as if the LAN were connected directly to its home network. Hence, when IP mobile, a mobile LAN's tunneled network traffic must traverse one or more foreign networks that may not be trusted. This traffic could be subject to eavesdropping, interception, modification, or redirection by malicious nodes in these foreign networks. To protect network traffic passing through the tunnels, OpenSSH is used as a means of encryption because it prevents surveillance, modification, and redirection of mobile LAN traffic passing across foreign networks. Since the software is found in the public domain, is available for most current operating systems, and is commonly used to provide secure network communications, OpenSSH is the software of choice.

  19. Propagation Characteristics in an Underground Shopping Area for 5GHz-band Wireless Access Systems

    Science.gov (United States)

    Itokawa, Kiyohiko; Kita, Naoki; Sato, Akio; Matsue, Hideaki; Mori, Daisuke; Watanabe, Hironobu

    5-GHz band wireless access systems, such as the RLAN (Radio Local Area Network) system of IEEE802.11a, HiperLAN/2, HiSWANa and AWA, are developed and provide transmission rates over 20 Mbps for indoor use. Those 5-GHz access systems are expected to extend service areas from the office to the so-called “hot-spot" in public areas. Underground shopping malls are one of the anticipated service areas for such a nomadic wireless access service. Broadband propagation characteristics are required for radio zone design in an underground mall environment despite previous results obtained by narrow band measurements. This paper presents results of an experimental study on the propagation characteristics for broadband wireless access systems in an underground mall environment. First, broadband propagation path loss is measured and formulated considering human body shadowing. A ray trace simulation is used to clarify the basic propagation mechanism in such a closed environment. Next, a distance dependency of the delay spread during a crowded time period, rush hour, is found to be at most 65 nsec, which is under the permitted maximum value of the present 5-GHz systems. Finally, above propagation characteristics support the result of transmission test carried out by using AWA equipment.

  20. Adaptive Naive Bayes classification for wireless sensor networks

    NARCIS (Netherlands)

    Zwartjes, G.J.

    2017-01-01

    Wireless Sensor Networks are tiny devices equipped with sensors and wireless communication. These devices observe environments and communicatie about these observations. Machine Learning techniques are of interest for Wireless Sensor Network applications since they can reduce the amount of needed

  1. Impact of High Power Interference Sources in Planning and Deployment of Wireless Sensor Networks and Devices in the 2.4 GHz Frequency Band in Heterogeneous Environments

    Directory of Open Access Journals (Sweden)

    Francisco Falcone

    2012-11-01

    Full Text Available In this work, the impact of radiofrequency radiation leakage from microwave ovens and its effect on 802.15.4 ZigBee-compliant wireless sensor networks operating in the 2.4 GHz Industrial Scientific Medical (ISM band is analyzed. By means of a novel radioplanning approach, based on electromagnetic field simulation of a microwave oven and determination of equivalent radiation sources applied to an in-house developed 3D ray launching algorithm, estimation of the microwave oven’s power leakage is obtained for the complete volume of an indoor scenario. The magnitude and the variable nature of the interference is analyzed and the impact in the radio link quality in operating wireless sensors is estimated and compared with radio channel measurements as well as packet measurements. The measurement results reveal the importance of selecting an adequate 802.15.4 channel, as well as the Wireless Sensor Network deployment strategy within this type of environment, in order to optimize energy consumption and increase the overall network performance. The proposed method enables one to estimate potential interference effects in devices operating within the 2.4 GHz band in the complete scenario, prior to wireless sensor network deployment, which can aid in achieving the most optimal network topology.

  2. Multi-Robot, Multi-Target Particle Swarm Optimization Search in Noisy Wireless Environments

    Energy Technology Data Exchange (ETDEWEB)

    Kurt Derr; Milos Manic

    2009-05-01

    Multiple small robots (swarms) can work together using Particle Swarm Optimization (PSO) to perform tasks that are difficult or impossible for a single robot to accomplish. The problem considered in this paper is exploration of an unknown environment with the goal of finding a target(s) at an unknown location(s) using multiple small mobile robots. This work demonstrates the use of a distributed PSO algorithm with a novel adaptive RSS weighting factor to guide robots for locating target(s) in high risk environments. The approach was developed and analyzed on multiple robot single and multiple target search. The approach was further enhanced by the multi-robot-multi-target search in noisy environments. The experimental results demonstrated how the availability of radio frequency signal can significantly affect robot search time to reach a target.

  3. Integration of Wireless Technologies in Smart University Campus Environment: Framework Architecture

    Science.gov (United States)

    Khamayseh, Yaser; Mardini, Wail; Aljawarneh, Shadi; Yassein, Muneer Bani

    2015-01-01

    In this paper, the authors are particularly interested in enhancing the education process by integrating new tools to the teaching environments. This enhancement is part of an emerging concept, called smart campus. Smart University Campus will come up with a new ubiquitous computing and communication field and change people's lives radically by…

  4. 3D workflow for HDR image capture of projection systems and objects for CAVE virtual environments authoring with wireless touch-sensitive devices

    Science.gov (United States)

    Prusten, Mark J.; McIntyre, Michelle; Landis, Marvin

    2006-02-01

    A 3D workflow pipeline is presented for High Dynamic Range (HDR) image capture of projected scenes or objects for presentation in CAVE virtual environments. The methods of HDR digital photography of environments vs. objects are reviewed. Samples of both types of virtual authoring being the actual CAVE environment and a sculpture are shown. A series of software tools are incorporated into a pipeline called CAVEPIPE, allowing for high-resolution objects and scenes to be composited together in natural illumination environments [1] and presented in our CAVE virtual reality environment. We also present a way to enhance the user interface for CAVE environments. The traditional methods of controlling the navigation through virtual environments include: glove, HUD's and 3D mouse devices. By integrating a wireless network that includes both WiFi (IEEE 802.11b/g) and Bluetooth (IEEE 802.15.1) protocols the non-graphical input control device can be eliminated. Therefore wireless devices can be added that would include: PDA's, Smart Phones, TabletPC's, Portable Gaming consoles, and PocketPC's.

  5. Design and development of Solar Powered Wireless Telemetering System (SPWTS) for Environmental Radiation Monitoring (ERM) of nuclear power plants

    International Nuclear Information System (INIS)

    Mariappan, Bhuvaneswari; Ramachandran, Shanmugalakshmi

    2014-01-01

    Presently, the real time environmental radiation monitoring system installed in the nuclear power plant is based on LAN. Generally data from the surveillance instrument are collected at regular intervals using a lap-top or system/units and taken to the laboratory for downloading the archival data. So a need was felt to design and develop Solar powered Wireless Telemetering System (SPWTS) for Environmental Radiation Monitoring (ERM) of Nuclear Power Plants. SPWTS is used for real-time monitoring and wireless transmission of the on-line data to the Central Control Unit (CCU) to investigate the history of monitored data. Thus, in this paper a wireless mode using Zigbee is proposed, thereby improving scalability, flexibility and continuous radiological surveillance along with data archival facility. The proposed Solar Powered Wireless Telemetering System (SPWTS) comprising of transmitter, intermediate devices and receiver units transmits the ERM data to Central Control Unit (CCU) for storage and display to RADAS unit. In order to meet the coverage distance without data loss, suitable number of repeaters/routers are configured and joined in the network. The entire wireless telemetry system is powered up by solar cells with rechargeable battery backup facility, SPWTS suitable for ERM data transmission module will replace the wired Ethernet environment by wireless mode thereby improving scalability, flexibility and continuous radiological surveillance of the gamma dose monitoring. This module also proposes solutions for wireless transmission of safety related critical data to a remote control unit. Finally, this module promotes interoperability within hierarchical framework by reducing the amount of changes that could be introduced into the existing system. (author)

  6. Ultra-Reliable Communication in a Factory Environment for 5G Wireless Networks

    DEFF Research Database (Denmark)

    Singh, Bikramjit; Lee, Zexian; Tirkkonen, Olav

    2016-01-01

    The focus of this paper on mission-critical Communications in a 5G cellular communication system. Technologies to provide ultra-reliable communication, with 99:999 % availability in a factory environment are studied. We have analysed the feasibility requirements for ultra-reliable communication...... are compared. Last, the importance of multi-hop communication and multi-point coordination schemes are highlighted to improve the reliable communication in presence of interference and clutter. Keywords—5G; mission-critical communications; ultra-reliable communication; availability; reliability...

  7. Energy efficiency in future wireless broadband networks

    CSIR Research Space (South Africa)

    Masonta, MT

    2012-10-01

    Full Text Available greener economy and environment. In this research, we investigate the concept of green radio communications in wireless networks and discuss approaches for energy efficient solutions in wireless broadband network deployments. These solutions include...

  8. Electromagnetic interference-aware transmission scheduling and power control for dynamic wireless access in hospital environments.

    Science.gov (United States)

    Phunchongharn, Phond; Hossain, Ekram; Camorlinga, Sergio

    2011-11-01

    We study the multiple access problem for e-Health applications (referred to as secondary users) coexisting with medical devices (referred to as primary or protected users) in a hospital environment. In particular, we focus on transmission scheduling and power control of secondary users in multiple spatial reuse time-division multiple access (STDMA) networks. The objective is to maximize the spectrum utilization of secondary users and minimize their power consumption subject to the electromagnetic interference (EMI) constraints for active and passive medical devices and minimum throughput guarantee for secondary users. The multiple access problem is formulated as a dual objective optimization problem which is shown to be NP-complete. We propose a joint scheduling and power control algorithm based on a greedy approach to solve the problem with much lower computational complexity. To this end, an enhanced greedy algorithm is proposed to improve the performance of the greedy algorithm by finding the optimal sequence of secondary users for scheduling. Using extensive simulations, the tradeoff in performance in terms of spectrum utilization, energy consumption, and computational complexity is evaluated for both the algorithms.

  9. A Uniform Publish-Subscribe Infrastructure for Communication in Wireless Mobile Environments

    DEFF Research Database (Denmark)

    Brønsted, Jeppe; Hansen, Klaus Marius; Thorup, Rolf

    2006-01-01

    In near future the transportation sector will be communication enabled. Devices in vehicles will be able to communicate and thus make a new range of services possible. However, heterogeneous communication capabilities and vehicle mobility complicates the art of designing and implementing these ne...... communication is handled uniformly. By showing how the infrastructure is used in a concrete instance we argue that it meets the requirements for middleware stated above and provides a good programming model for distributed systems in mobile environments......In near future the transportation sector will be communication enabled. Devices in vehicles will be able to communicate and thus make a new range of services possible. However, heterogeneous communication capabilities and vehicle mobility complicates the art of designing and implementing these new...... systems and therefore it is important to have communication middleware that hides the complexity of low level network programming and presents a clean and understandable abstraction over communication to the application programmer. It has previously been shown that the publish-subscribe messaging paradigm...

  10. Remote assessment of cultural heritage environments with wireless sensor array networks.

    Science.gov (United States)

    Agbota, Henoc; Mitchell, John E; Odlyha, Marianne; Strlič, Matija

    2014-05-19

    The logistics and cost of environmental monitoring can represent challenges for heritage managers, partly because of the sheer number of environmental parameters to consider. There is a need for a system, capable of monitoring the holistic impact of the environment on cultural materials while remaining relatively easy to use and providing remote access. This paper describes a dosimetric system based on piezoelectric quartz crystal technology. The prototype sensing module consists of an array of piezoelectric quartz crystals (PQC) coated with different metals (Fe, Cu, Ni and Sn) and includes a temperature and relative humidity sensor. The communication module involves an 802.15.4 low-power radio and a GPRS gateway which allows real time visualisation of the measurements online. An energy management protocol ensures that the system consumes very low power between measurements. The paper also describes the results and experiences from two heritage field deployments, at Apsley House in London, UK, and at the Royal Palaces of Abomey in Benin. Evaluation of PQC measurements, temperature, relative humidity and the rate of successful transmission over the communication systems are also reported.

  11. Economic justification for LAN installation in an oilfield equipment manufacturing operation

    International Nuclear Information System (INIS)

    Frishmuth, R.E.; Gariepy, J.A.

    1992-01-01

    The oil field equipment manufacturing business, like any other business working in a world wide environment, is becoming interested in reducing the amount of time required to take a product from initial concept to the market place. The most recent concept being employed to achieve this goal is concurrent engineering. This paper discusses the use of local area networks connecting personal computers to facilitate both traditional engineering and manufacturing organizations and concurrent engineering concepts. The key to making either type of organizational structure work well is communication. As companies have moved away from large mainframe computers toward individual, stand alone, personal computers, communications as well as various databases have been difficult to maintain. The authors attempt to show how a LAN would help to solve problems with data integrity, communication and speed of product development. These ideas are combined with discussion of anticipated cost savings as well as LAN installation cost. The authors show that the initial cost of LAN installation can easily be justified by the costs saved in product development

  12. Determining Threshold Distance Providing Less Interference for Wireless Medical Implant Communication Systems in Coexisting Environments under Shadow Fading Conditions

    Directory of Open Access Journals (Sweden)

    Selman KULAÇ

    2017-08-01

    Full Text Available Important interference problems will be able to be encountered especially close areas to the hospitals where wireless implantable medical systems' communication traffic occurs heavily in near future. It is possible that these interferences could cause wireless implant devices to malfunction and harmful effects on patients. In this study, it is proposed to determine threshold distance in order to get less interference for wireless implantable medical systems under shadow fading conditions where MICS band and MetAids band users coexist intensely simultaneously. In this method, threshold power according to the \\cite{FCC} is pulled down by adding extra distance margin in order to minimize the interference effects to the MICS systems using confidence interval calculations. Because received signal strength just below the monitoring threshold power according to the \\cite{FCC} brings about much more interferences for the MICS systems even if listen-before-talk technique is applied.

  13. Wireless Access

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Wireless Access. Wireless connect to the Base station. Easy and Convenient access. Costlier as compared to the wired technology. Reliability challenges. We see it as a complementary technology to the DSL.

  14. Security For Wireless Sensor Network

    OpenAIRE

    Saurabh Singh,; Dr. Harsh Kumar Verma

    2011-01-01

    Wireless sensor network is highly vulnerable to attacks because it consists of various resourceconstrained devices with their low battery power, less memory, and associated low energy. Sensor nodescommunicate among themselves via wireless links. However, there are still a lot of unresolved issues in wireless sensor networks of which security is one of the hottest research issues. Sensor networks aredeployed in hostile environments. Environmental conditions along with resource-constraints give...

  15. A study on LAN applications in nuclear safety systems

    International Nuclear Information System (INIS)

    Kim, Sung; Lee, Young Ryul; Koo, Jun Mo; Han, Jai Bok

    1995-01-01

    It is a general tendency to digitalize the conventional relay based I and C systems in nuclear power plant. But, the digitalisation of nuclear safety systems has many a difficulty to surmount. The typical one thing of many difficulties is the data communication problem between local controllers and systems. The network architecture built with LAN (Local Area Network) in digital systems of the other industries are general. But in case of nuclear safety systems many considerations in point of safety and license are required to implement it in the field. In this parer, some considerations for applying LAN in nuclear safety systems were reviewed

  16. Corporate planning and LAN information systems as forums

    CERN Document Server

    Sabre, Ru Michael

    1992-01-01

    Corporate Planning and LAN: Information Systems as Forums provides information pertinent to the Forum Information System (FIS), a conceptual basis for all corporate planning. This book presents an information system which, by means of LAN, organizational development style prototyping, and organizational learning utilization, can open communications among managers, executives, owners, and employees in a corporate setting.Organized into 10 chapters, this book begins with an overview of the four phases to the eventual use of the FIS in a corporate setting. This text then explores FIS as part of a

  17. Performance Comparison of Wireless Sensor Network Standard Protocols in an Aerospace Environment: ISA100.11a and ZigBee Pro

    Science.gov (United States)

    Wagner, Raymond S.; Barton, Richard J.

    2011-01-01

    Standards-based wireless sensor network (WSN) protocols are promising candidates for spacecraft avionics systems, offering unprecedented instrumentation flexibility and expandability. Ensuring reliable data transport is key, however, when migrating from wired to wireless data gathering systems. In this paper, we conduct a rigorous laboratory analysis of the relative performances of the ZigBee Pro and ISA100.11a protocols in a representative crewed aerospace environment. Since both operate in the 2.4 GHz radio frequency (RF) band shared by systems such as Wi-Fi, they are subject at times to potentially debilitating RF interference. We compare goodput (application-level throughput) achievable by both under varying levels of 802.11g Wi-Fi traffic. We conclude that while the simpler, more inexpensive ZigBee Pro protocol performs well under moderate levels of interference, the more complex and costly ISA100.11a protocol is needed to ensure reliable data delivery under heavier interference. This paper represents the first published, rigorous analysis of WSN protocols in an aerospace environment that we are aware of and the first published head-to-head comparison of ZigBee Pro and ISA100.11a.

  18. Integrated 3d printed wireless sensing system for environmental monitoring

    KAUST Repository

    Farooqui, Muhammad Fahad; Shamim, Atif

    2017-01-01

    transmitters on a panel. The wireless sensor device may be configured to take environment measurements, such as temperature, gas, humidity, and wirelessly communicate the environment measurements to a remote computing device, in addition, the present disclosure

  19. A Wireless Sensor Network for Growth Environment Measurement and Multi-Band Optical Sensing to Diagnose Tree Vigor.

    Science.gov (United States)

    Kameoka, Shinichi; Isoda, Shuhei; Hashimoto, Atsushi; Ito, Ryoei; Miyamoto, Satoru; Wada, Genki; Watanabe, Naoki; Yamakami, Takashi; Suzuki, Ken; Kameoka, Takaharu

    2017-04-27

    We have tried to develop the guidance system for farmers to cultivate using various phenological indices. As the sensing part of this system, we deployed a new Wireless Sensor Network (WSN). This system uses the 920 MHz radio wave based on the Wireless Smart Utility Network that enables long-range wireless communication. In addition, the data acquired by the WSN were standardized for the advanced web service interoperability. By using these standardized data, we can create a web service that offers various kinds of phenological indices as secondary information to the farmers in the field. We have also established the field management system using thermal image, fluorescent and X-ray fluorescent methods, which enable the nondestructive, chemical-free, simple, and rapid measurement of fruits or trees. We can get the information about the transpiration of plants through a thermal image. The fluorescence sensor gives us information, such as nitrate balance index (NBI), that shows the nitrate balance inside the leaf, chlorophyll content, flavonol content and anthocyanin content. These methods allow one to quickly check the health of trees and find ways to improve the tree vigor of weak ones. Furthermore, the fluorescent x-ray sensor has the possibility to quantify the loss of minerals necessary for fruit growth.

  20. Implementation of a Low-Cost Energy and Environment Monitoring System Based on a Hybrid Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Dong Sik Kim

    2017-01-01

    Full Text Available A low-cost hybrid wireless sensor network (WSN that utilizes the 917 MHz band Wireless Smart Utility Network (Wi-SUN and a 447 MHz band narrow bandwidth communication network is implemented for electric metering and room temperature, humidity, and CO2 gas measurements. A mesh network connection that is commonly utilized for the Internet of Things (IoT is used for the Wi-SUN under the Contiki OS, and a star connection is used for the narrow bandwidth network. Both a duty-cycling receiver algorithm and a digitally controlled temperature-compensated crystal oscillator algorithm for frequency reference are implemented at the physical layer of the receiver to accomplish low-power and low-cost wireless sensor node design. A two-level temperature-compensation approach, in which first a fixed third-order curve and then a sample-based first-order curve are applied, is proposed using a conventional AT-cut quartz crystal resonator. The developed WSN is installed in a home and provides reliable data collection with low construction complexity and power consumption.

  1. A Wireless Sensor Network for Growth Environment Measurement and Multi-Band Optical Sensing to Diagnose Tree Vigor

    Directory of Open Access Journals (Sweden)

    Shinichi Kameoka

    2017-04-01

    Full Text Available We have tried to develop the guidance system for farmers to cultivate using various phenological indices. As the sensing part of this system, we deployed a new Wireless Sensor Network (WSN. This system uses the 920 MHz radio wave based on the Wireless Smart Utility Network that enables long-range wireless communication. In addition, the data acquired by the WSN were standardized for the advanced web service interoperability. By using these standardized data, we can create a web service that offers various kinds of phenological indices as secondary information to the farmers in the field. We have also established the field management system using thermal image, fluorescent and X-ray fluorescent methods, which enable the nondestructive, chemical-free, simple, and rapid measurement of fruits or trees. We can get the information about the transpiration of plants through a thermal image. The fluorescence sensor gives us information, such as nitrate balance index (NBI, that shows the nitrate balance inside the leaf, chlorophyll content, flavonol content and anthocyanin content. These methods allow one to quickly check the health of trees and find ways to improve the tree vigor of weak ones. Furthermore, the fluorescent x-ray sensor has the possibility to quantify the loss of minerals necessary for fruit growth.

  2. Modeling and preliminary characterization of passive, wireless temperature sensors for harsh environment applications based on periodic structures

    Science.gov (United States)

    Delfin Manriquez, Diego I.

    Wireless temperature sensing has attained significant attention in recent years due to the increasing need to develop reliable and affordable sensing solutions for energy conversion systems and other harsh environment applications. The development of next generation sensors for energy production processing parameters, such as temperature and pressure, can result in better performance of the system. Particularly, continuous temperature monitoring in energy conversion systems can result in enhancements such as better system integrity, less pollution and higher thermal efficiencies. However, the conditions experienced in these system components hinder the performance of current solutions due to the presence of semi-conductor materials and welded joints. Additionally, the use of wired systems can result in complex wiring networks, increasing the cost of installation, maintenance and sensor replacement. Therefore, next generation sensing solutions must be developed to overcome current challenges in systems where adverse conditions are present. This research project proposes two novel passive, wireless temperature sensor designs based on concepts of guided mode resonance filters (GMRF) and metamaterials. For the GMRF, a tri-layer structure using a metallic encasing and a circular aperture grating layer was developed to have a resonance frequency of 10 GHz. While for the metamaterial-based sensor a continuation of previous work was presented by utilizing a dielectric substrate and an array of commercially available metallic washers divided in two layers. For both designs, High Frequency Structure Simulator (HFSS) from ANSYSRTM was employed to assess the feasibility of the sensor as well as to optimize the geometry and guide the fabrication process. A systematic approach consisting of evaluating the unit cell, then assessing the number of periods needed, and finally characterizing the response of the final sensor was followed for each case. After the modeling process was

  3. Wireless virtualization

    CERN Document Server

    Wen, Heming; Le-Ngoc, Tho

    2013-01-01

    This SpringerBriefs is an overview of the emerging field of wireless access and mobile network virtualization. It provides a clear and relevant picture of the current virtualization trends in wireless technologies by summarizing and comparing different architectures, techniques and technologies applicable to a future virtualized wireless network infrastructure. The readers are exposed to a short walkthrough of the future Internet initiative and network virtualization technologies in order to understand the potential role of wireless virtualization in the broader context of next-generation ubiq

  4. An elementary research on wireless transmission of holographic 3D moving pictures

    Science.gov (United States)

    Takano, Kunihiko; Sato, Koki; Endo, Takaya; Asano, Hiroaki; Fukuzawa, Atsuo; Asai, Kikuo

    2009-05-01

    In this paper, a transmitting process of a sequence of holograms describing 3D moving objects over the communicating wireless-network system is presented. A sequence of holograms involves holograms is transformed into a bit stream data, and then it is transmitted over the wireless LAN and Bluetooth. It is shown that applying this technique, holographic data of 3D moving object is transmitted in high quality and a relatively good reconstruction of holographic images is performed.

  5. Study of Wireless Transmission Protocol Technology for Use in Flight Line Environment to Assist the Data Loading and Downloading on Aircraft

    National Research Council Canada - National Science Library

    Meng, Ow

    2004-01-01

    ... into the use of wireless tmnsmission technology to complement or replace the manual method of loading the critical data file from the command station onto every F-16 aircraft, The present wireless technology...

  6. ARHITEKTURA LAN Z NAT, VAROVANIMI VLAN IN WIFI DOSTOPOM

    OpenAIRE

    Mlakar, Jure

    2012-01-01

    Omrežja so postala del našega vsakdana in so prisotna vsepovsod. Poznamo dve vrsti tipičnih omrežij: LAN (Angl. Local Area Network) in WAN (angl. Wide Area Network). LAN omrežja uporabljamo za povezavo računalnikov in drugih mrežnih naprav v omejenem geografskem področju, kot je npr. stanovanjska hiša, šola, laboratorij ali poslovna zgradba. WAN omrežja, se uporabljajo za pokritje večjih geografskih območij (vsako omrežje, ki poteka preko mestnih, regionalnih ali državnih mej). Ta om...

  7. Wireless Internet

    NARCIS (Netherlands)

    el Zarki, M.; Heijenk, Geert; Lee, Kenneth S.; Bidgoli, H.

    This chapter addresses the topic of wireless Internet, the extension of the wireline Internet architecture to the wireless domain. As such the chapter introduces the reader to the dominant characteristics of the Internet, from its structure to the protocols that control the forwarding of data and

  8. 15 Gbit/s indoor optical wireless systems employing fast adaptation and imaging reception in a realistic environment

    Science.gov (United States)

    Alsaadi, Fuad E.

    2016-03-01

    Optical wireless systems are promising candidates for next-generation indoor communication networks. Optical wireless technology offers freedom from spectrum regulations and, compared to current radio-frequency networks, higher data rates and increased security. This paper presents a fast adaptation method for multibeam angle and delay adaptation systems and a new spot-diffusing geometry, and also considers restrictions needed for complying with eye safety regulations. The fast adaptation algorithm reduces the computational load required to reconfigure the transmitter in the case of transmitter and/or receiver mobility. The beam clustering approach enables the transmitter to assign power to spots within the pixel's field of view (FOV) and increases the number of such spots. Thus, if the power per spot is restricted to comply with eye safety standards, the new approach, in which more spots are visible within the FOV of the pixel, leads to enhanced signal-to-noise ratio (SNR). Simulation results demonstrate that the techniques proposed in this paper lead to SNR improvements that enable reliable operation at data rates as high as 15 Gbit/s. These results are based on simulation and not on actual measurements or experiments.

  9. DATA transmission by 2.4 GHz radio frequency and LAN from Nuclear Power Plant to office

    International Nuclear Information System (INIS)

    Tsuji, Kenji; Masuda, Ryota; Hukui, Takuya

    2011-01-01

    Additional monitoring is occasionally done on suspicious equipment such as pumps, motors, valves and so on, when monitoring parameters are different from normal operation in Nuclear Power Plant. If the suspicious equipment is located in high radiation area, it is hard to arrange for the additional monitoring. So, wireless data transmission system is desired. And maintenance persons desire to watch the additional monitoring data in their office on P.C. We can enable to transfer the desired live data from sensors in NPP to the maintenance person's office, using by ZigBee system connected to LAN. In order to enlarge the operating term, the battery for sensors is switched on or off by the signal related to sleeping function on ZigBee sensor-terminal. (author)

  10. Indoor location system based on discriminant-adaptive neural network in IEEE 802.11 environments.

    Science.gov (United States)

    Fang, Shih-Hau; Lin, Tsung-Nan

    2008-11-01

    This brief paper presents a novel localization algorithm, named discriminant-adaptive neural network (DANN), which takes the received signal strength (RSS) from the access points (APs) as inputs to infer the client position in the wireless local area network (LAN) environment. We extract the useful information into discriminative components (DCs) for network learning. The nonlinear relationship between RSS and the position is then accurately constructed by incrementally inserting the DCs and recursively updating the weightings in the network until no further improvement is required. Our localization system is developed in a real-world wireless LAN WLAN environment, where the realistic RSS measurement is collected. We implement the traditional approaches on the same test bed, including weighted kappa-nearest neighbor (WKNN), maximum likelihood (ML), and multilayer perceptron (MLP), and compare the results. The experimental results indicate that the proposed algorithm is much higher in accuracy compared with other examined techniques. The improvement can be attributed to that only the useful information is efficiently extracted for positioning while the redundant information is regarded as noise and discarded. Finally, the analysis shows that our network intelligently accomplishes learning while the inserted DCs provide sufficient information.

  11. IR wireless cluster synapses of HYDRA very large neural networks

    Science.gov (United States)

    Jannson, Tomasz; Forrester, Thomas

    2008-04-01

    RF/IR wireless (virtual) synapses are critical components of HYDRA (Hyper-Distributed Robotic Autonomy) neural networks, already discussed in two earlier papers. The HYDRA network has the potential to be very large, up to 10 11-neurons and 10 18-synapses, based on already established technologies (cellular RF telephony and IR-wireless LANs). It is organized into almost fully connected IR-wireless clusters. The HYDRA neurons and synapses are very flexible, simple, and low-cost. They can be modified into a broad variety of biologically-inspired brain-like computing capabilities. In this third paper, we focus on neural hardware in general, and on IR-wireless synapses in particular. Such synapses, based on LED/LD-connections, dominate the HYDRA neural cluster.

  12. Games and social Nnetworks in popular lan house: a look on anthropology uses in collective and sociability "local club"

    Directory of Open Access Journals (Sweden)

    Carla Barros

    2009-03-01

    Full Text Available This article aims to discuss some aspects of the appropriations of computer technology in the universe of urban classes, focusing on the environment of lan houses and sailing in social networks and games. The study has the principal orientation of the anthropological approach to consumption, using a methodology of ethnographic inspiration. " Even when they do not have computers at home, the young people surveyed showed a great familiarity with certain aspects of digital life, due to high frequency in the lan houses. The survey results show that ownership of these spaces as a sort of local club, as well as practice of navigation collective - are "collective machinery, working in a collaborative world, where many users are on a same computer, interacting during navigation - the importance of strengthening the social ties existing practices related to virtual networks of relationships.

  13. Design and initial deployment of the wireless local area networking infrastructure at Sandia National Laboratories.

    Energy Technology Data Exchange (ETDEWEB)

    Long, John P.; Hamill, Michael J.; Mitchell, M. G.; Miller, Marc M.; Witzke, Edward L.; Wiener, Dallas J

    2006-11-01

    A major portion of the Wireless Networking Project at Sandia National Laboratories over the last few years has been to examine IEEE 802.11 wireless networking for possible use at Sandia and if practical, introduce this technology. This project team deployed 802.11a, b, and g Wireless Local Area Networking at Sandia. This report examines the basics of wireless networking and captures key results from project tests and experiments. It also records project members thoughts and designs on wireless LAN architecture and security issues. It documents some of the actions and milestones of this project, including pilot and production deployment of wireless networking equipment, and captures the team's rationale behind some of the decisions made. Finally, the report examines lessons learned, future directions, and conclusions.

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

    Directory of Open Access Journals (Sweden)

    Woo-Yong Choi

    2008-10-01

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

  15. On Bandwidth Efficient Modulation for High-Data-Rate Wireless LAN Systems

    Directory of Open Access Journals (Sweden)

    Stolpman Victor

    2002-01-01

    Full Text Available We address the problem of high-data-rate orthogonal frequency division multiplexed (OFDM systems under restrictive bandwidth constraints. Based on recent theoretic results, multiple-input multiple-output (MIMO configurations are best suited for this problem. In this paper, we examine several MIMO configurations suitable for high rate transmission. In all scenarios considered, perfect channel state information (CSI is assumed at the receiver. In constrast, availability of CSI at the transmitter is addressed separately. We show that powerful space-time codes can be developed by combining some simple well-known techniques. In fact, we show that for certain configurations, these space-time MIMO configurations are near optimum in terms of outage capacity as compared to previously published codes. Performance evaluation of these techniques is demonstrated within the IEEE 802.11a framework via Monte Carlo simulations.

  16. Software development for efficient description of FIR filters of wireless LAN systems, in VHDL

    OpenAIRE

    Καινούργιος, Σωτήριος

    2005-01-01

    Υλοποίηση παραμετροποιημένων FIR φίλτρων με την βοήθεια της γλώσσας περιγραφής υλικού VHDL. Μελέτη των αποτελεσμάτων για χώρο και περιοχή που καταλαμβάνει ο σχεδιαμσός. FIR implementation with the description language VHDL. We discuss their results for area and the delay of each diagram (FIR filter).

  17. Distributed software applications in JAVA for portable processors operating on a wireless LAN

    OpenAIRE

    Rothenhaus, Kurt J.

    1999-01-01

    Approved for pubic release; distribution is unlimited As the wave of future Information Technology makes its way into the construction and design of new ships and submarines, it is imperative to examine methods to thoroughly economically backfit older platforms with similar technology. Affordable, Commercial-off-the-shelf (COTS) industrial products have provided us with a means to reduce miscommunication and exponentially increase the availability of information via small pen based compute...

  18. Media Access Time-Rearrangement of Wireless LAN for a Multi-Radio Collocated Platform

    Science.gov (United States)

    Shin, Sang-Heon; Kim, Chul; Park, Sang Kyu

    With the advent of new Radio Access Technologies (RATs), it is inevitable that several RATs will co-exist, especially in the license-exempt band. In this letter, we present an in-depth adaptation of the proactive time-rearrangement (PATRA) scheme for IEEE 802.11 WLAN. The PATRA is a time division approach for reducing interference from a multi-radio device. Because IEEE 802.11 is based on carrier sensing and contention mechanism, it is the most suitable candidate to adapt the PATRA.

  19. Estimating the number of competing terminals without a state variation detector in wireless LAN

    Science.gov (United States)

    Lim, Jaechan; Kim, Taejin; Hong, Daehyoung

    2013-12-01

    Estimating the number of competing terminals n (who wish to transmit a packet at the same time) in the IEEE 802.11 system is important for system throughput performance because optimal back-off window size needs to be selected based on n. Therefore, as a new approach for estimating n, we propose H infinity filter that does not need a state variation detector as opposed to the cases of previously proposed approaches. The state variation detector's flaw is incurring tracking latency in addition to the side effect of increased computational cost. All previously proposed approaches demand the employment of the state variation detector to detect the variation of n in the IEEE 802.11 system. By employing H infinity filter, we show improved throughput performance of the system compared to that of previously proposed approaches (e.g., the Kalman filter and particle filter) based on the improved performance in tracking n. In this paper, we justify the superiority of the proposed approach in the terms of tracking performance, throughput performance, and computational complexity.

  20. Wireless Cybersecurity

    Science.gov (United States)

    2013-04-01

    completely change the entire landscape. For example, under the quantum computing regime, factoring prime numbers requires only polynomial time (i.e., Shor’s...AFRL-OSR-VA-TR-2013-0206 Wireless Cybersecurity Biao Chen Syracuse University April 2013 Final Report DISTRIBUTION A...19a. NAME OF RESPONSIBLE PERSON 19b. TELEPHONE NUMBER (Include area code) 21-02-2013 FINAL REPORT 01-04-2009 TO 30-11-2012 Wireless Cybersecurity

  1. VPLS: an effective technology for building scalable transparent LAN services

    Science.gov (United States)

    Dong, Ximing; Yu, Shaohua

    2005-02-01

    Virtual Private LAN Service (VPLS) is generating considerable interest with enterprises and service providers as it offers multipoint transparent LAN service (TLS) over MPLS networks. This paper describes an effective technology - VPLS, which links virtual switch instances (VSIs) through MPLS to form an emulated Ethernet switch and build Scalable Transparent Lan Services. It first focuses on the architecture of VPLS with Ethernet bridging technique at the edge and MPLS at the core, then it tries to elucidate the data forwarding mechanism within VPLS domain, including learning and aging MAC addresses on a per LSP basis, flooding of unknown frames and replication for unknown, multicast, and broadcast frames. The loop-avoidance mechanism, known as split horizon forwarding, is also analyzed. Another important aspect of VPLS service is its basic operation, including autodiscovery and signaling, is discussed. From the perspective of efficiency and scalability the paper compares two important signaling mechanism, BGP and LDP, which are used to set up a PW between the PEs and bind the PWs to a particular VSI. With the extension of VPLS and the increase of full mesh of PWs between PE devices (n*(n-1)/2 PWs in all, a n2 complete problem), VPLS instance could have a large number of remote PE associations, resulting in an inefficient use of network bandwidth and system resources as the ingress PE has to replicate each frame and append MPLS labels for remote PE. So the latter part of this paper focuses on the scalability issue: the Hierarchical VPLS. Within the architecture of HVPLS, this paper addresses two ways to cope with a possibly large number of MAC addresses, which make VPLS operate more efficiently.

  2. CWSP Certified Wireless Security Professional Official Study Guide, Exam PW0-204

    CERN Document Server

    Coleman, David D; Harkins, Bryan E

    2010-01-01

    Sybex is now the official publisher for Certified Wireless Network Professional, the certifying vendor for the CWSP program. This guide covers all exam objectives, including WLAN discovery techniques, intrusion and attack techniques, 802.11 protocol analysis. Wireless intrusion-prevention systems implementation, layer 2 and 3 VPNs used over 802.11 networks, and managed endpoint security systems. It also covers enterprise/SMB/SOHO/Public-Network Security design models and security solution implementation, building robust security networks, wireless LAN management systems, and much more.

  3. [Research on WiFi-based wireless microscopy on a mobile phone and its application].

    Science.gov (United States)

    Hailan, Jin; Jing, Liu

    2012-11-01

    We proposed and realized a new device that acquires microscopic image wirelessly based on mobile phone and WiFi system. The mobile terminals could record, display and store the image from the far end via the wireless LAN. Using this system, a series of conceptual experiments on monitoring the microscopic images of common objects and liver cancer cells were successfully demonstrated. This system is expected to have important value in the experimental investigations on wirelessly monitoring the cell culture, and small insect etc.

  4. On limits of Wireless Communications in a Fading Environment: a General Parameterization Quantifying Performance in Fading Channel

    Directory of Open Access Journals (Sweden)

    Amit Grover

    2014-08-01

    Full Text Available The reliable services along with high throughput can be achieved by using wireless communication systems. These systems also provides a wide coverage because of their features, no doubt MIMO Communication System [1] is one among them. Features provided by these systems ensure the improved system coverage and increased data transmission rate by considering multiple numbers of transmitter and receiver antennas. In this article, the concept of equalization has been considered and finally the performance of the MIMO Systems in Rician flat fading [5] channel is compared with the Rayleigh flat fading channel. It has also been observed that the performance of these Systems in Rician Flat Fading Channel is the best as compare to the Rayleigh Flat Fading Channel [10]. It has been concluded that the successive interference methods provide better performance as compare to others, but their complexity is high. Simulation results shows that ML provides the better performance in comparison to other equalizers but Sphere decoder provides the best performance.

  5. Performance Comparison of Wireless Sensor Network Standard Protocols in an Aerospace Environment: ISA100.11a and ZigBee

    Science.gov (United States)

    Wagner, Raymond S.; Barton, Richard J.

    2011-01-01

    Wireless Sensor Networks (WSNs) can provide a substantial benefit in spacecraft systems, reducing launch weight and providing unprecedented flexibility by allowing instrumentation capabilities to grow and change over time. Achieving data transport reliability on par with that of wired systems, however, can prove extremely challenging in practice. Fortunately, much progress has been made in developing standard WSN radio protocols for applications from non-critical home automation to mission-critical industrial process control. The relative performances of candidate protocols must be compared in representative aerospace environments, however, to determine their suitability for spaceflight applications. In this paper, we will present the results of a rigorous laboratory analysis of the performance of two standards-based, low power, low data rate WSN protocols: ZigBee Pro and ISA100.11a. Both are based on IEEE 802.15.4 and augment that standard's specifications to build complete, multi-hop networking stacks. ZigBee Pro targets primarily the home and office automation markets, providing an ad-hoc protocol that is computationally lightweight and easy to implement in inexpensive system-on-a-chip components. As a result of this simplicity, however, ZigBee Pro can be susceptible to radio frequency (RF) interference. ISA100.11a, on the other hand, targets the industrial process control market, providing a robust, centrally-managed protocol capable of tolerating a significant amount of RF interference. To achieve these gains, a coordinated channel hopping mechanism is employed, which entails a greater computational complexity than ZigBee and requires more sophisticated and costly hardware. To guide future aerospace deployments, we must understand how well these standards relatively perform in analog environments under expected operating conditions. Specifically, we are interested in evaluating goodput -- application level throughput -- in a representative crewed environment

  6. Optimizing POF/PCF based optical switch for indoor LAN

    International Nuclear Information System (INIS)

    Bhuiyan, M M I; Rashid, M M; Ahmed, Sayem; Bhuiyan, M; Kajihara, M

    2013-01-01

    For indoor local area network (LAN) the Polymer optical fiber (POF) is mostly appropriate, because of its large core diameter and flexible material. A 1×2 optical switch for indoor LAN using POF and a shape memory alloy (SMA) coil actuator with magnetic latches was successfully fabricated and tested. To achieve switching by the movement of a POF, large displacement is necessary because the core diameter is large (e.g., 0.486mm). A SMA coil actuator is used for large displacement and a magnetic latching system is used for fixing the position of the shifted POF. The insertion loss is 0.40 to 0.50dB and crosstalk is more than 50dB without index-matching oil. Switching speed is less than 1s at a driving current of 80mA. A cycling test was performed 1.4 million times. Polymer clad fiber optical (PCF) switch also fabricated and tasted

  7. Open system LANs and their global interconnection electronics and communications reference series

    CERN Document Server

    Houldsworth, Jack; Caves, Keith; Mazda, FF

    2014-01-01

    Open System LANs and Their Global Interconnection focuses on the OSI layer 1 to 4 standards (the OSI bearer service) and also introduces TCP/IP and some of the proprietary PC Local Area Network (LAN) standards.The publication first provides an introduction to Local Area Networks (LANs) and Wide Area Networks (WANs), Open Systems Interconnection (OSI), and LAN standards. Discussions focus on MAC bridging, token bus, slotted ring, MAC constraints and design considerations, OSI functional standards, OSI model, value of the transport model, benefits and origins of OSI, and significance of the tran

  8. A Real-Time GPP Software-Defined Radio Testbed for the Physical Layer of Wireless Standards

    NARCIS (Netherlands)

    Schiphorst, Roelof; Hoeksema, F.W.; Slump, Cornelis H.

    2005-01-01

    We present our contribution to the general-purpose-processor-(GPP)-based radio. We describe a baseband software-defined radio testbed for the physical layer of wireless LAN standards. All physical layer functions have been successfully mapped on a Pentium 4 processor that performs these functions in

  9. Interview with Datin Goh Suet Lan on Business Coaching

    Directory of Open Access Journals (Sweden)

    Vahid Nimehchisalem

    2016-10-01

    Full Text Available I had the pleasure of meeting Datin Goh Suet Lan and one of the key members of her team, Mr Murali, in the Faculty of Modern Languages and Communication, Universiti Putra Malaysia with three of my colleagues, Associate Professor Dr Shamala Paramasivam (who initiated this meeting, Dr. Ilyana Binti Jalaluddin, and Dr. Ramiza Binti Darmi. At the end of this meeting, Datin graciously accepted the invitation for an E-mail interview, which is the result of what you are going to read here. The interview will show how it is possible to educate women who are the bread-winners of poverty-stricken families to work more wisely for a better living. In this interview, Datin, who is the president of an NGO called Women of Will (www.womenofwill.org.my, shares the insightful experiences she and her team have reaped in their journey of making a meaningful difference in their community.

  10. Hemolytic disease of the fetus and newborn caused by anti-Lan.

    Science.gov (United States)

    Brooks, Sarah; Squires, Jerry E

    2014-05-01

    Antibodies to the high-incidence red blood cell (RBC) antigen Lan (Langereis) are typically immunoglobulin G and have been shown to fix complement and cause hemolysis of Lan antigen-positive RBCs. Only three cases of hemolytic disease of the fetus and newborn (HDFN) have been reported involving anti-Lan and all have been characterized as "mild." A 26-year-old Hispanic female presented in her fifth pregnancy for routine obstetric care. Due to progressively rising anti-Lan titers, middle cerebral artery (MCA) Dopplers were performed. At 32 weeks of gestation, the antibody titer had reached 128; the MCA Doppler indicated that fetal anemia was severe. An intrauterine transfusion with Lan antigen-negative RBCs was performed and a viable infant was delivered 25 days later. Three cases of HDFN associated with anti-Lan have been previously reported. While these cases have been associated with somewhat variable serologic findings, none have resulted in fetal demise or severe symptomatology requiring pre- or postnatal intervention other than routine phototherapy. The current report, however, suggests that in some instances anti-Lan can result in a more severe form of HDFN requiring more aggressive prenatal therapy. In spite of previous case reports suggesting that anti-Lan is associated with relatively mild HDFN, this case suggests that in some instances, this antibody can cause severe HDFN requiring prenatal intervention. © 2013 American Association of Blood Banks.

  11. Experimental demonstration of an improved EPON architecture using OFDMA for bandwidth scalable LAN emulation

    DEFF Research Database (Denmark)

    Deng, Lei; Zhao, Ying; Yu, Xianbin

    2011-01-01

    We propose and demonstrate an improved Ethernet passive optical network (EPON) architecture supporting bandwidth-scalable physical layer local area network (LAN) emulation. Due to the use of orthogonal frequency division multiple access (OFDMA) technology for the LAN traffic transmission, there i...

  12. Konfigurasi Server Cloud Storage pada Jaringan LAN pada LAB Diploma III Manajemen Informatika UM Metro

    Directory of Open Access Journals (Sweden)

    Arif Hidayat

    2017-07-01

    Berdasarkan hasil pengujian sistem dapat disimpulkan bahwa Konfigurasi Server Cloud Storage pada Jaringan LAN ini dapat  menjadi alat bantu Penyimpanan data bisa diakses dan dilakukan melalui folder di komputer atau aplikasi yang terikat dengan pemilik akun di layanan yang bersangkutan. Kata Kunci--- Konfigurasi Server Cloud Storage ; Cloud Storange pada Jaringan LAN; Cloud Storange.

  13. Wireless Tots

    Science.gov (United States)

    Scott, Lee-Allison

    2003-01-01

    The first wireless technology program for preschoolers was implemented in January at the Primrose School at Bentwater in Atlanta, Georgia, a new corporate school operated by Primrose School Franchising Co. The new school serves as a testing and training facility for groundbreaking educational approaches, including emerging innovations in…

  14. Wireless Technician

    Science.gov (United States)

    Tech Directions, 2011

    2011-01-01

    One of the hottest areas in technology is invisible. Wireless communications allow people to transmit voice messages, data, and other signals through the air without physically connecting senders to receivers with cables or wires. And the technology is spreading at lightning speed. Cellular phones, personal digital assistants, and wireless…

  15. Wireless Network Penetration Testing and Security Auditing

    Directory of Open Access Journals (Sweden)

    Wang Shao-Long

    2016-01-01

    Full Text Available IEEE802.11 wireless wireless networks have security issues that are vulnerable to a variety of attacks. Due to using radio to transport data, attackers can bypass firewalls, sniff sensitive information, intercept packets and send malicious packets. Security auditing and penetration testing is expected to ensure wireless networks security. The contributions of this work are analyzed the vulnerability and types of attacks pertaining to IEEE 802.11 WLAN, performed well known attacks in a laboratory environment to conduct penetration tests to confirm whether our wireless network is hackable or not. WAIDPS is configured as auditing tool to view wireless attacks, such as WEP/WPA/WPA2 cracking, rouge access points, denial of service attack. WAIDPS is designed to detect wireless intrusion with additional features. Penetration testing and auditing will mitigate the risk and threatening to protect WALN.

  16. An Improved Indoor Positioning System Using RGB-D Cameras and Wireless Networks for Use in Complex Environments

    Directory of Open Access Journals (Sweden)

    Jaime Duque Domingo

    2017-10-01

    Full Text Available This work presents an Indoor Positioning System to estimate the location of people navigating in complex indoor environments. The developed technique combines WiFi Positioning Systems and depth maps, delivering promising results in complex inhabited environments, consisting of various connected rooms, where people are freely moving. This is a non-intrusive system in which personal information about subjects is not needed and, although RGB-D cameras are installed in the sensing area, users are only required to carry their smart-phones. In this article, the methods developed to combine the above-mentioned technologies and the experiments performed to test the system are detailed. The obtained results show a significant improvement in terms of accuracy and performance with respect to previous WiFi-based solutions as well as an extension in the range of operation.

  17. Ad hoc mobile wireless networks principles, protocols and applications

    CERN Document Server

    Sarkar, Subir Kumar; Puttamadappa, C

    2007-01-01

    Ad hoc mobile wireless networks have seen increased adaptation in a variety of disciplines because they can be deployed with simple infrastructures and virtually no central administration. In particular, the development of ad hoc wireless and sensor networks provides tremendous opportunities in areas including disaster recovery, defense, health care, and industrial environments. Ad Hoc Mobile Wireless Networks: Principles, Protocols and Applications explains the concepts, mechanisms, design, and performance of these systems. It presents in-depth explanations of the latest wireless technologies

  18. Ad hoc mobile wireless networks principles, protocols, and applications

    CERN Document Server

    Sarkar, Subir Kumar

    2013-01-01

    The military, the research community, emergency services, and industrial environments all rely on ad hoc mobile wireless networks because of their simple infrastructure and minimal central administration. Now in its second edition, Ad Hoc Mobile Wireless Networks: Principles, Protocols, and Applications explains the concepts, mechanism, design, and performance of these highly valued systems. Following an overview of wireless network fundamentals, the book explores MAC layer, routing, multicast, and transport layer protocols for ad hoc mobile wireless networks. Next, it examines quality of serv

  19. Heterogeneous wireless/wireline optical access networks with the R-EAT as backend component

    Science.gov (United States)

    Hagedorn, Klaus; Gindera, Ralf; Stohr, Andreas; Jager, Dieter

    2004-09-01

    A heterogeneous wireless/wireline optical transmission link using a reflection type electroabsorption transceiver (R-EAT) is presented. Simultaneous transmission of full-duplex broadband wireless LAN (WLAN) channels and 1Gb/s base band data is experimentally demonstrated. The system link employs sub-carrier multiplexing (SCM) and two optical channels for full duplex transmission of various analog WLAN channels and downlink digital base band data. The developed link architecture is suitable for simultaneous transmission of broadband wireline and wireless signals, it enables the coexistence and interoperability between wireline and wireless access technologies. The developed R-EAT component employed in this wireline/wireless access system, features "single-chip-component" base stations in access networks with star type topology where only a single optical fiber is used for bidirectional optical transmission. The R-EAT can be used within the optical C-band (1530- 1560nm) and is suitable for (D)WDM networks. Bit error rate measurements demonstrate the capabilities of the R-EAT for 1Gb/s base band transmission. The analog performance for WLAN transmission is characterised by a spurious free dynamic range (SFDR) of more than 75dB and 90dB for uplink and downlink transmission, respectively. The link gain for uplink and downlink transmission is -42dB and -37dB, respectively. The demonstrates the analog performances of the R-EAT for being used in wireless access networks such as W-LAN.

  20. Wireless Sensor Networks TestBed: ASNTbed

    CSIR Research Space (South Africa)

    Dludla, AG

    2013-05-01

    Full Text Available Wireless sensor networks (WSNs) have been used in different types of applications and deployed within various environments. Simulation tools are essential for studying WSNs, especially for exploring large-scale networks. However, WSN testbeds...

  1. Predictive power control in wireless sensor networks

    NARCIS (Netherlands)

    Chincoli, M.; Syed, Aly; Mocanu, D.C.; Liotta, A.

    2016-01-01

    Communications in Wireless Sensor Networks (WSNs) are affected by dynamic environments, variable signal fluctuations and interference. Thus, prompt actions are necessary to achieve dependable communications and meet quality of service requirements. To this end, the reactive algorithms used in

  2. Systems assessment of water savings impact of controlled environment agriculture (CEA) utilizing wirelessly networked Sense•Decide•Act•Communicate (SDAC) systems.

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Jonathan T.; Baynes, Edward E., Jr.; Aguirre,Carlos (University of Texas at El Paso, El Paso, TX); Jordan, Jon (University of Arizona, Tucson, AZ); Giacomelli, Gene (University of Arizona, Tucson, AZ); Waggoner, Justin (New Mexico State University, Las Cruces, NM); Loest, Clint (New Mexico State University, Las Cruces, NM); Szumel, Leo; Nakaoka, Tyler; Pate, Ronald C.; Berry, Nina M.; Pohl, Phillip Isabio; Aguirre, Francisco Luis (Invernaderos y Maquinaria Aguirre, Cd., Aldama, Chihuahua, Mexico); Aguilar, Jose (University of Texas at El Paso, El Paso, TX); Gupta, Vipin P.; Ochoa, Juan (University of Texas at El Paso, El Paso, TX); Davis, Jesse Zehring; Ramos, Damian (University of Texas at El Paso, El Paso, TX)

    2005-02-01

    Reducing agricultural water use in arid regions while maintaining or improving economic productivity of the agriculture sector is a major challenge. Controlled environment agriculture (CEA, or, greenhouse agriculture) affords advantages in direct resource use (less land and water required) and productivity (i.e., much higher product yield and quality per unit of resources used) relative to conventional open-field practices. These advantages come at the price of higher operating complexity and costs per acre. The challenge is to implement and apply CEA such that the productivity and resource use advantages will sufficiently outweigh the higher operating costs to provide for overall benefit and viability. This project undertook an investigation of CEA for livestock forage production as a water-saving alternative to open-field forage production in arid regions. Forage production is a large consumer of fresh water in many arid regions of the world, including the southwestern U.S. and northern Mexico. With increasing competition among uses (agriculture, municipalities, industry, recreation, ecosystems, etc.) for limited fresh water supplies, agricultural practice alternatives that can potentially maintain or enhance productivity while reducing water use warrant consideration. The project established a pilot forage production greenhouse facility in southern New Mexico based on a relatively modest and passive (no active heating or cooling) system design pioneered in Chihuahua, Mexico. Experimental operations were initiated in August 2004 and carried over into early-FY05 to collect data and make initial assessments of operational and technical system performance, assess forage nutrition content and suitability for livestock, identify areas needing improvement, and make initial assessment of overall feasibility. The effort was supported through the joint leveraging of late-start FY04 LDRD funds and bundled CY2004 project funding from the New Mexico Small Business Technical

  3. Data centric wireless sensor networks

    NARCIS (Netherlands)

    Dulman, S.O.; Havinga, Paul J.M.

    2005-01-01

    The vision of wirteless sensing systems requires the development of devices and technologies that can be pervasive without being intrusive. The basic component of such a smart environment will be a small node with sensing and wireless communications capabilities, able to organize itself flexibly

  4. Když v Lanžhotě túkli...

    Czech Academy of Sciences Publication Activity Database

    Altman, Karel

    2015-01-01

    Roč. 51, č. 4 (2015), s. 15 ISSN 0323-1542 Institutional support: RVO:68378076 Keywords : fight * neighbor relations * conflict * court * city Lanžhot Subject RIV: AC - Archeology, Anthropology, Ethnology

  5. Artificial intelligence in wireless communications

    CERN Document Server

    Rondeau, Thomas W

    2009-01-01

    This cutting-edge resource offers practical overview of cognitive radio, a paradigm for wireless communications in which a network or a wireless node changes its transmission or reception parameters. The alteration of parameters is based on the active monitoring of several factors in the external and internal radio environment. This book offers a detailed description of cognitive radio and its individual parts. Practitioners learn how the basic processing elements and their capabilities are implemented as modular components. Moreover, the book explains how each component can be developed and t

  6. Wireless Biological Electronic Sensors.

    Science.gov (United States)

    Cui, Yue

    2017-10-09

    The development of wireless biological electronic sensors could open up significant advances for both fundamental studies and practical applications in a variety of areas, including medical diagnosis, environmental monitoring, and defense applications. One of the major challenges in the development of wireless bioelectronic sensors is the successful integration of biosensing units and wireless signal transducers. In recent years, there are a few types of wireless communication systems that have been integrated with biosensing systems to construct wireless bioelectronic sensors. To successfully construct wireless biological electronic sensors, there are several interesting questions: What types of biosensing transducers can be used in wireless bioelectronic sensors? What types of wireless systems can be integrated with biosensing transducers to construct wireless bioelectronic sensors? How are the electrical sensing signals generated and transmitted? This review will highlight the early attempts to address these questions in the development of wireless biological electronic sensors.

  7. An agent-based signal processing in-node environment for real-time human activity monitoring based on wireless body sensor networks

    NARCIS (Netherlands)

    Aiello, F.; Bellifemine, F.L.; Fortino, G.; Galzarano, S.; Gravina, R.

    2011-01-01

    Nowadays wireless body sensor networks (WBSNs) have great potential to enable a broad variety of assisted living applications such as human biophysical/biochemical control and activity monitoring for health care, e-fitness, emergency detection, emotional recognition for social networking, security,

  8. [Development of Bluetooth wireless sensors].

    Science.gov (United States)

    Moor, C; Schwaibold, M; Roth, H; Schöchlin, J; Bolz, A

    2002-01-01

    Wireless communication could help to overcome current obstacles in medical devices and could enable medical services to offer completely new scenarios in health care. The Bluetooth technology which is the upcoming global market leader in wireless communication turned out to be perfectly suited not only for consumer market products but also in the medical environment [1]. It offers a low power, low cost connection in the medium range of 1-100 m with a bandwidth of currently 723.2 kbaud. This paper describes the development of a wireless ECG device and a Pulse Oximeter. Equipped with a Bluetooth port, the measurement devices are enabled to transmit data between the sensor and a Bluetooth-monitor. Therefore, CSR's Bluetooth protocol embedded two-processor and embedded single-processor architecture has been used.

  9. A medical-grade wireless architecture for remote electrocardiography.

    Science.gov (United States)

    Kang, Kyungtae; Park, Kyung-Joon; Song, Jae-Jin; Yoon, Chang-Hwan; Sha, Lui

    2011-03-01

    In telecardiology, electrocardiogram (ECG) signals from a patient are acquired by sensors and transmitted in real time to medical personnel across a wireless network. The use of IEEE 802.11 wireless LANs (WLANs), which are already deployed in many hospitals, can provide ubiquitous connectivity and thus allow cardiology patients greater mobility. However, engineering issues, including the error-prone nature of wireless channels and the unpredictable delay and jitter due to the nondeterministic nature of access to the wireless medium, need to be addressed before telecardiology can be safely realized. We propose a medical-grade WLAN architecture for remote ECG monitoring, which employs the point-coordination function (PCF) for medium access control and Reed-Solomon coding for error control. Realistic simulations with uncompressed two-lead ECG data from the MIT-BIH arrhythmia database demonstrate reliable wireless ECG monitoring; the reliability of ECG transmission exceeds 99.99% with the initial buffering delay of only 2.4 s.

  10. The List of Available Names (LAN): A new generation for stable taxonomic names in zoology?

    Science.gov (United States)

    Alonso-Zarazaga, Miguel A; Fautin, Daphne Gail; Michel, Ellinor

    2016-01-01

    The List of Available Names in Zoology (LAN) is an inventory of names with specific scope in time and content, presented and approved in parts, and constituted as a cumulative index of names available for use in zoological nomenclature. It was defined in Article 79 in the fourth edition of the International Code of Zoological Nomenclature. The LAN is likely to gain importance with the development of the online Official Registry for Zoological Nomenclature (ZooBank) as it is potentially a source of many nomenclaturally certified names. Article 79 describes the deliberative process for adding large numbers of names to the LAN simultaneously, detailing steps and chronology for submission of a candidate Part to the LAN and consideration of a candidate Part by the public and Commission, but it is largely mute about the contents of a candidate Part. It does make clear that a name within the scope of a Part but not on the LAN has no nomenclatural standing, even if it had previously been considered available, thereby preventing long-forgotten names from displacing accepted ones and the accumulation of nomina dubia. Thus, for taxa on the LAN, nomenclatural archaeology - the resurrecting of old unused names to replace by priority names in current usage - will not be worthwhile. Beyond that, it has been unclear if Article 79 is intended to document every available name known within the scope of the Part, or if its intention is to pare the inventory of available names within the scope of the Part. Consideration by the Commission and two committees to deal with the LAN have defined steps to implement Article 79 with the latter intent. Procedures for consideration of a candidate Part are defined in a manual, published as an appendix in this volume.

  11. Maximizing lifetime of wireless sensor networks using genetic approach

    DEFF Research Database (Denmark)

    Wagh, Sanjeev; Prasad, Ramjee

    2014-01-01

    The wireless sensor networks are designed to install the smart network applications or network for emergency solutions, where human interaction is not possible. The nodes in wireless sensor networks have to self organize as per the users requirements through monitoring environments. As the sensor......-objective parameters are considered to solve the problem using genetic algorithm of evolutionary approach.......The wireless sensor networks are designed to install the smart network applications or network for emergency solutions, where human interaction is not possible. The nodes in wireless sensor networks have to self organize as per the users requirements through monitoring environments. As the sensor...

  12. Outline of the wireless hut built in 1957 and the old living hut built in 1969 at Syowa Station, Antarctica and outside environment -Preface-

    Directory of Open Access Journals (Sweden)

    Zenkichi Hirayama

    2002-09-01

    Full Text Available It has been decided to dismantle the wireless hut built in 1957 and the old living hut built in 1969 at Syowa Station, Antarctica in accordance with a renewal project plan. A Commission of Construction Experts, the Architect Committee brought the above two buildings as test samples to Japan and in cooperation with several research institutes and researchers, investigated the effect of aging. We herein report the those results.

  13. Propagación por estacas en Lulo, Solanum quitoense lan Use of cuttings for Solsnum quitoense lan. propagation

    Directory of Open Access Journals (Sweden)

    Cifuentes Fabricio

    1989-12-01

    Full Text Available Dos ensayos fueron llevados a cabo en los invernaderos de la Facultad de Agronomía de la Universidad Nacional de Colombia en Bogotá con el propósito de evaluar el enraizamiento de estacas terminales de lulo. Se aplicó al ácido indolbutírico y el naftalenacetico en las dosis de 500 y
    1500 ppm y las estacas se pusieron a enraizar en escoria y cascarilla de arroz. Se tomaron como parámetros fisiológicos el número de ra íces primarias, el peso seco total de las
    ra ices, la longitud y el diámetro de las mismas y el número de ra íces secundarias. Los resultados mostraron que el ácido indolbutírico a la dosis de 1500 ppm es el tratamiento más indicado para promover el desarrollo de raíces en estacas terminales de lulo especialmente a los 50 días después de la siembra. Por otra parte, la escoria fue el mejor sustrato de los dos ensayados posiblemente debido a su alta retención de humedad. Finalmente de todos los parámetros estudiados
    los más influenciados por los tratamientos fueron el número y la longitud de las raíces primarias y el peso seco total.Two greenhouse experiments were conducted to evaluate the rooting of terminal cuttings of Solanum quitoense Lan. The
    cuttings were treated with indol butiric acid and naftalenacetic acid in doses of 500 and 1500 ppm and then planted in scum and rice shell as soil substrates. The number of primary and secondary roots, the lenght and diameter of the primary roots, and the root dry weight were taken 50 days after planting. The most roots, was found when the cuttings were dipped in 1500 ppm of indolbutiric acid and planted in scum. Probably, the combination of the right amount of the hormone applied and the
    high water retention of the substrate was the best for the rooting.

  14. Advanced Signal Processing for Wireless Multimedia Communications

    Directory of Open Access Journals (Sweden)

    Xiaodong Wang

    2000-01-01

    Full Text Available There is at present a worldwide effort to develop next-generation wireless communication systems. It is envisioned that many of the future wireless systems will incorporate considerable signal-processing intelligence in order to provide advanced services such as multimedia transmission. In general, wireless channels can be very hostile media through which to communicate, due to substantial physical impediments, primarily radio-frequency interference and time-arying nature of the channel. The need of providing universal wireless access at high data-rate (which is the aim of many merging wireless applications presents a major technical challenge, and meeting this challenge necessitates the development of advanced signal processing techniques for multiple-access communications in non-stationary interference-rich environments. In this paper, we present some key advanced signal processing methodologies that have been developed in recent years for interference suppression in wireless networks. We will focus primarily on the problem of jointly suppressing multiple-access interference (MAI and intersymbol interference (ISI, which are the limiting sources of interference for the high data-rate wireless systems being proposed for many emerging application areas, such as wireless multimedia. We first present a signal subspace approach to blind joint suppression of MAI and ISI. We then discuss a powerful iterative technique for joint interference suppression and decoding, so-called Turbo multiuser detection, that is especially useful for wireless multimedia packet communications. We also discuss space-time processing methods that employ multiple antennas for interference rejection and signal enhancement. Finally, we touch briefly on the problems of suppressing narrowband interference and impulsive ambient noise, two other sources of radio-frequency interference present in wireless multimedia networks.

  15. Modeling Multistandard Wireless Networks in OPNET

    DEFF Research Database (Denmark)

    Zakrzewska, Anna; Berger, Michael Stübert; Ruepp, Sarah Renée

    2011-01-01

    Future wireless communication is emerging towards one heterogeneous platform. In this new environment wireless access will be provided by multiple radio technologies that are cooperating and complementing one another. The paper investigates the possibilities of developing such a multistandard sys...... system using OPNET Modeler. A network model consisting of LTE interworking with WLAN and WiMAX is considered from the radio resource management perspective. In particular, implementing a joint packet scheduler across multiple systems is discussed more in detail....

  16. Wireless ATM : handover issues

    OpenAIRE

    Jiang, Fan; Käkölä, Timo

    1998-01-01

    Basic aspects of cellular systems and the ATM transmission technology are introduced. Wireless ATM is presented as a combination of radio ATM and mobile ATM. Radio ATM is a wireless extension of an ATM connection while mobile ATM contains the necessary extensions to ATM to support mobility. Because the current ATM technology does not support mobility, handover becomes one of the most important research issues for wireless ATM. Wireless ATM handover requirements are thus analysed. A handover s...

  17. Wireless communication technology NFC

    OpenAIRE

    MÁROVÁ, Kateřina

    2014-01-01

    Aim of this bachelor thesis is to handle the issue of new wireless communication technology NFC (Near Field Communication) including a comparison of advantages and disadvantages of NFC with other wireless technologies (Bluetooth, Wi-Fi, etc.). NFC is a technology for wireless communications between different electronic devices, one of which is typically a mobile phone. Near Field Communication allows wireless communication at very short distance by approaching or enclosing two devices and can...

  18. Wireless steganography

    Science.gov (United States)

    Agaian, Sos S.; Akopian, David; D'Souza, Sunil

    2006-02-01

    Modern mobile devices are some of the most technologically advanced devices that people use on a daily basis and the current trends in mobile phone technology indicate that tasks achievable by mobile devices will soon exceed our imagination. This paper undertakes a case study of the development and implementation of one of the first known steganography (data hiding) applications on a mobile device. Steganography is traditionally accomplished using the high processing speeds of desktop or notebook computers. With the introduction of mobile platform operating systems, there arises an opportunity for the users to develop and embed their own applications. We take advantage of this opportunity with the introduction of wireless steganographic algorithms. Thus we demonstrates that custom applications, popular with security establishments, can be developed also on mobile systems independent of both the mobile device manufacturer and mobile service provider. For example, this might be a very important feature if the communication is to be controlled exclusively by authorized personnel. The paper begins by reviewing the technological capabilities of modern mobile devices. Then we address a suitable development platform which is based on Symbian TM/Series60 TM architecture. Finally, two data hiding applications developed for Symbian TM/Series60 TM mobile phones are presented.

  19. Multi-Channel Wireless Sensor Networks: Protocols, Design and Evaluation

    OpenAIRE

    Durmaz, O.

    2009-01-01

    Pervasive systems, which are described as networked embedded systems integrated with everyday environments, are considered to have the potential to change our daily lives by creating smart surroundings and by their ubiquity, just as the Internet. In the last decade, “Wireless Sensor Networks��? have appeared as one of the real-world examples of pervasive systems by combining automated sensing, embedded computing and wireless networking into tiny embedded devices. A wireless sensor network typ...

  20. Design and implementation about the campus wireless network

    International Nuclear Information System (INIS)

    Qi Fazhi; An Dehai; Wang Yanming; Cui Tao; Chen Gang; Liu Baoxu

    2007-01-01

    With the development of network applications, flexibility and wieldy is becoming more and more important for network users. Based on the analysis of the needs of campus wireless network. This article design and analysis the deployment mechanism, register system and protection system of wireless network. Built a wireless network system base on IHEP network environment, realization the 'always and everywhere' access the network in the IHEP campus area. (authors)

  1. Distributed Cross-layer Monitoring in Wireless Mesh Networks

    OpenAIRE

    Panmin, Ye; Yong,

    2009-01-01

    Wireless mesh networks has rapid development over the last few years. However, due to properties such as distributed infrastructure and interference, which strongly affect the performance of wireless mesh networks, developing technology has to face the challenge of architecture and protocol design issues. Traditional layered protocols do not function efficiently in multi-hop wireless environments. To get deeper understanding on interaction of the layered protocols and optimize the performance...

  2. Quality assessment in lan houses through the adaptation of the servqual instrument

    Directory of Open Access Journals (Sweden)

    Tiago José Menezes Gonçalves

    2012-03-01

    Full Text Available This work was conducted with the objective of developing an adapted questionnaire from the SERVQUAL instrument to measure the quality of services provided by Lan Houses. In addition, the use of analysis Quartiles  was investigated in prioritizing the items to perform corrective actions to improve the quality of service analysis. For achieve this objectives, an adaptation of the SERVQUAL instrument was developed based on the literature and interviews with managers of Lan Houses, from where information was extracted for its adaptation to the object of study. Once developed, the instrument was used and the managerial implications of its use (in conjunction with the Quartiles Analysis were discussed with the Lan House’s manager, from where feedback was obtained for the validity of the model developed.

  3. 姚兰的穷爸爸%Yao Lan's Poor Father

    Institute of Scientific and Technical Information of China (English)

    Jack

    2004-01-01

    @@ When Yao Lan was born, her parents were both working in a factory that produced newsprint paper. The paper from the factory was considered good quality and all the workers enjoyed a fairly prosperous( 富裕的 ) lifestyle, not that they were rich. They were really only comfortable, but much more than most of their counterparts(对应的人) in other factories. So, when Yao Lan came along, Yao Long, her father and An Ying, her mother were both very happy. Yao Lan's father and mother each earned three hundred yuan and in the early eighties that amount went a long way. They knew they could take good care of their daughter and provide her a decent upbringing(抚育).

  4. Preservation of Isparta Yılan Kırkan (Yılan Kıran) Fountain within the Scope of Sustainability

    OpenAIRE

    Meryem Elif Çelebi Yakartepe; Ayşe Betül Gökarslan

    2014-01-01

    Sustainable architecture is an approach which accepts the climatic and tomographic data as a necessary preliminary data package by favoring the relationship between human and nature and which strives to use the sources economically. The reflection of sustainable architecture approach to preservation - restoration discipline is including the architectural inheritance to daily life with its unique or new function by restoring it. The restoration decisions of Yılan Kırkan Fountain in Isparta...

  5. All-optical LAN architectures based on arrayed waveguide grating multiplexers

    Science.gov (United States)

    Woesner, Hagen

    1998-10-01

    The paper presents optical LAN topologies which are made possible using an Arrayed Waveguide Grating Multiplexer (AWGM) instead of a passive star coupler to interconnect stations in an all-optical LAN. Due to the collision-free nature of an AWGM it offers the n-fold bandwidth compared to the star coupler. Virtual ring topologies appear (one ring on each wavelength) if the number of stations attached to the AWGM is a prime number. A method to construct larger networks using Cayley graphs is shown. An access protocol to avoid collisions on the proposed network is outlined.

  6. The Asymptotic Behaviour of a Stochastic 3D LANS-α Model

    International Nuclear Information System (INIS)

    Caraballo, Tomas; Marquez-Duran, Antonio M.; Real, Jose

    2006-01-01

    The long-time behaviour of a stochastic 3D LANS-α model on a bounded domain is analysed. First, we reformulate the model as an abstract problem. Next, we establish sufficient conditions ensuring the existence of stationary (steady state) solutions of this abstract nonlinear stochastic evolution equation, and study the stability properties of the model. Finally, we analyse the effects produced by stochastic perturbations in the deterministic version of the system (persistence of exponential stability as well as possible stabilisation effects produced by the noise). The general results are applied to our stochastic LANS-α system throughout the paper

  7. CCNA Wireless Study Guide

    CERN Document Server

    Lammle, Todd

    2010-01-01

    A complete guide to the CCNA Wireless exam by leading networking authority Todd Lammle. The CCNA Wireless certification is the most respected entry-level certification in this rapidly growing field. Todd Lammle is the undisputed authority on networking, and this book focuses exclusively on the skills covered in this Cisco certification exam. The CCNA Wireless Study Guide joins the popular Sybex study guide family and helps network administrators advance their careers with a highly desirable certification.: The CCNA Wireless certification is the most respected entry-level wireless certification

  8. Wireless Handhelds to Support Clinical Nursing Practicum

    Science.gov (United States)

    Wu, Cheng-Chih; Lai, Chin-Yuan

    2009-01-01

    This paper reports our implementation and evaluation of a wireless handheld learning environment used to support a clinical nursing practicum course. The learning environment was designed so that nursing students could use handhelds for recording information, organizing ideas, assessing patients, and also for interaction and collaboration with…

  9. Voice over IP in Wireless Heterogeneous Networks

    DEFF Research Database (Denmark)

    Fathi, Hanane; Chakraborty, Shyam; Prasad, Ramjee

    with the deployment of wireless heterogeneous systems, both speech and data traffic are carrried over wireless links by the same IP-based packet-switched infrastructure. However, this combination faces some challenges due to the inherent properties of the wireless network. The requirements for good quality VoIP...... communications are difficult to achieve in a time-varying environment due to channel errors and traffic congestion and across different systems. The provision of VoIP in wireless heterogeneous networks requires a set of time-efficient control mechanisms to support a VoIP session with acceptable quality....... The focus of Voice over IP in Wierless Heterogeneous Networks is on mechanisms that affect the VoIP user satisfaction  while not explicitly involved in the media session. This relates to the extra delays introduced by the security and the signaling protocols used to set up an authorized VoIP session...

  10. Integrated 3d printed wireless sensing system for environmental monitoring

    KAUST Repository

    Farooqui, Muhammad Fahad

    2017-12-21

    Disclosed are various embodiments of a wireless sensor device for monitoring environment conditions. A wireless sensor device may comprise, for example, a computing device, printable circuitry, sensors, and antennas combined with one or more transmitters on a panel. The wireless sensor device may be configured to take environment measurements, such as temperature, gas, humidity, and wirelessly communicate the environment measurements to a remote computing device, in addition, the present disclosure relates to a method of assembling the wireless sensor device. The method may comprise printing sensors, circuitry, and antennas to a panel; folding the panel to form an enclosure comprising a plurality of side panels; and attaching the plurality of side panels to a circuit board panel.

  11. Data aggregation in wireless sensor networks using the SOAP protocol

    International Nuclear Information System (INIS)

    Al-Yasiri, A; Sunley, A

    2007-01-01

    Wireless sensor networks (WSN) offer an increasingly attractive method of data gathering in distributed system architectures and dynamic access via wireless connectivity. Wireless sensor networks have physical and resource limitations, this leads to increased complexity for application developers and often results in applications that are closely coupled with network protocols. In this paper, a data aggregation framework using SOAP (Simple Object Access Protocol) on wireless sensor networks is presented. The framework works as a middleware for aggregating data measured by a number of nodes within a network. The aim of the study is to assess the suitability of the protocol in such environments where resources are limited compared to traditional networks

  12. Data aggregation in wireless sensor networks using the SOAP protocol

    Energy Technology Data Exchange (ETDEWEB)

    Al-Yasiri, A; Sunley, A [School of Computing, Science and Engineering, University of Salford, Greater Manchester, M5 4WT (United Kingdom)

    2007-07-15

    Wireless sensor networks (WSN) offer an increasingly attractive method of data gathering in distributed system architectures and dynamic access via wireless connectivity. Wireless sensor networks have physical and resource limitations, this leads to increased complexity for application developers and often results in applications that are closely coupled with network protocols. In this paper, a data aggregation framework using SOAP (Simple Object Access Protocol) on wireless sensor networks is presented. The framework works as a middleware for aggregating data measured by a number of nodes within a network. The aim of the study is to assess the suitability of the protocol in such environments where resources are limited compared to traditional networks.

  13. Design and implementation of a software defined HiperLAN/2 physical layer model for simulation purposes

    NARCIS (Netherlands)

    van Hoesel, L.F.W.

    2002-01-01

    In this Master of Science thesis a simulation model of the HiperLAN/2 physical layer is designed and implemented. The model should provide insight in the demodulation functions that are necessary in HiperLAN/2 and it should be useful for determining channel selection and computational requirements

  14. Energy Efficient Error-Correcting Coding for Wireless Systems

    NARCIS (Netherlands)

    Shao, X.

    2010-01-01

    The wireless channel is a hostile environment. The transmitted signal does not only suffers multi-path fading but also noise and interference from other users of the wireless channel. That causes unreliable communications. To achieve high-quality communications, error correcting coding is required

  15. Energy efficiency of error correcting mechanisms for wireless communications

    NARCIS (Netherlands)

    Havinga, Paul J.M.

    We consider the energy efficiency of error control mechanisms for wireless communication. Since high error rates are inevitable to the wireless environment, energy efficient error control is an important issue for mobile computing systems. Although good designed retransmission schemes can be optimal

  16. Practical network design techniques a complete guide for WANs and LANs

    CERN Document Server

    Held, Gilbert

    2004-01-01

    This new edition has two parts. The first part focuses on wide area networks; the second, which is entirely new, focuses on local area networks. Because Ethernet emerged victorious in the LAN war, the second section pays particular attention to Ethernet design and performance characteristics.

  17. Improving LAN Performance Based on IEEE802.1Q VLAN Switching Techniques

    Directory of Open Access Journals (Sweden)

    Dhurgham Abdulridha Jawad AL-Khaffaf

    2017-11-01

    Full Text Available VLAN is a set of users in different isolated logical LANs or broadcasting domains, they are communicated as a same LAN i.e. same broadcasting domain. Ethernet protocol is very popular over networks because it has a simple of implementation and ease of configuration. However, the support of Quality of Service (QoS has become an essential merit of Ethernet network. In this context, the problems of large network and data transport delay have been regained significant importance. Alleviating the end to end delay by using the VLAN technology to enhance the network performance. In this paper, we analyze and evaluate the performance of LAN and VLAN networks in different scenarios. Measuring key performance indicators such as traffic sent, traffic received, average delay and throughput. The simulation was carried out by employing OPNET 17.5 Student Version. Two different scenarios are presented to observe the performance of LAN and VLAN networks. The simulation results illustrated that there is more existing traffic without VLAN technology. Hence, VLANs prohibit the access to the network resources of other departments. Also, VLAN has half average queuing delay compared with no VLAN scenario. Therefore, VLANs can improve bandwidth utilization, power, speed and security.

  18. Techniques of collecting, controling and analyzing information about functioning LAN JINET

    International Nuclear Information System (INIS)

    Mazepa, E.Yu.; Parsadanyan, N.G.; Fariseev, V.Ya.; Modebadze, Z.S.

    1992-01-01

    The brief description of programming capability for controling and analyzing information about functioning LAN JINET is presented. Operating in the menu mode an administrator and engineer of JINET are consider a network temprorary state, tracing map of token and statistic of commands, used by users of the network. 5 refs.; 10 figs

  19. Supporting Command and Control (C2) of an Embarked Commander: Tunneling SIPRNet Data Across an UNCLAS Wireless LAN

    Science.gov (United States)

    2011-09-01

    that you did to help me through this process. Your efforts and guidance truly made this a success. To SPAWAR SCTD expert Stephanie Koontz , your...ty%20and%20Safety%20Services/05– 500%20Security%20Services/5510.36A.pdf [accessed June 19, 2011]. [28] S. Koontz . “Secret client tunneling...devices - KOV-26 talon user procedures.” Unpublished survey, SPAWAR, Point Loma, CA. [29] S. Koontz . “Secret client tunneling devices - KIV-54 user

  20. Demonstration of fully functional MIMO wireless LAN transmission over GI-MMF for in-building networks

    NARCIS (Netherlands)

    Zou, S.; Chen, H.; Huijskens, F.M.; Cao, Z.; Tangdiongga, E.; Koonen, A.M.J.

    2013-01-01

    We propose a low-cost optically-fed architecture capable of increasing the capacity and overall coverage of IEEE 802.11n MIMO WLAN system for in-building networks. A fully functional transmission over GI-MMF was demonstrated employing 2×3 MIMO configuration.

  1. Wireless mesh networks.

    Science.gov (United States)

    Wang, Xinheng

    2008-01-01

    Wireless telemedicine using GSM and GPRS technologies can only provide low bandwidth connections, which makes it difficult to transmit images and video. Satellite or 3G wireless transmission provides greater bandwidth, but the running costs are high. Wireless networks (WLANs) appear promising, since they can supply high bandwidth at low cost. However, the WLAN technology has limitations, such as coverage. A new wireless networking technology named the wireless mesh network (WMN) overcomes some of the limitations of the WLAN. A WMN combines the characteristics of both a WLAN and ad hoc networks, thus forming an intelligent, large scale and broadband wireless network. These features are attractive for telemedicine and telecare because of the ability to provide data, voice and video communications over a large area. One successful wireless telemedicine project which uses wireless mesh technology is the Emergency Room Link (ER-LINK) in Tucson, Arizona, USA. There are three key characteristics of a WMN: self-organization, including self-management and self-healing; dynamic changes in network topology; and scalability. What we may now see is a shift from mobile communication and satellite systems for wireless telemedicine to the use of wireless networks based on mesh technology, since the latter are very attractive in terms of cost, reliability and speed.

  2. Mobility needs and wireless solutions

    DEFF Research Database (Denmark)

    Saugstrup, Dan; Henten, Anders

    The main purpose of this report is to spell out a methodological approach to the analysis of user needs with respect to mobility. Furthermore, this methodological approach is used in an exemplary analysis of the relationship between user needs and technology solutions offered by different wireless...... technologies. The report is based on a research approach, emphasizing important aspects in relation to developing more user oriented mobile services and applications in a heterogeneous network environment. As a staring point, Scandinavian research within the field of social science concerning mobility...... is described and discussed. Furthermore different wireless technologies are briefly described and discussed in relation to possible transmission capacities and coverage areas. In addition to this, a preliminary framework regarding the implications of mobility on the use and development of mobile services...

  3. Analysis and Testing of Mobile Wireless Networks

    Science.gov (United States)

    Alena, Richard; Evenson, Darin; Rundquist, Victor; Clancy, Daniel (Technical Monitor)

    2002-01-01

    Wireless networks are being used to connect mobile computing elements in more applications as the technology matures. There are now many products (such as 802.11 and 802.11b) which ran in the ISM frequency band and comply with wireless network standards. They are being used increasingly to link mobile Intranet into Wired networks. Standard methods of analyzing and testing their performance and compatibility are needed to determine the limits of the technology. This paper presents analytical and experimental methods of determining network throughput, range and coverage, and interference sources. Both radio frequency (BE) domain and network domain analysis have been applied to determine wireless network throughput and range in the outdoor environment- Comparison of field test data taken under optimal conditions, with performance predicted from RF analysis, yielded quantitative results applicable to future designs. Layering multiple wireless network- sooners can increase performance. Wireless network components can be set to different radio frequency-hopping sequences or spreading functions, allowing more than one sooner to coexist. Therefore, we ran multiple 802.11-compliant systems concurrently in the same geographical area to determine interference effects and scalability, The results can be used to design of more robust networks which have multiple layers of wireless data communication paths and provide increased throughput overall.

  4. Intelligent Wireless Sensor Network

    OpenAIRE

    Saeed, Bakhtiar I.; Mehrdadi, Bruce

    2010-01-01

    In recent years, there has been significant increase in utilisation of embedded-microcontrollers in broad range of applications extending from commercial products to industrial process system monitoring. Furthermore, improvements in speed, size and power consumption of microcontrollers with added wireless capabilities has provided new generation of applications. These include versatile and\\ud low cost solutions in wireless sensor networking applications such as wireless system monitoring and ...

  5. Environment

    DEFF Research Database (Denmark)

    Valentini, Chiara

    2017-01-01

    The term environment refers to the internal and external context in which organizations operate. For some scholars, environment is defined as an arrangement of political, economic, social and cultural factors existing in a given context that have an impact on organizational processes and structures....... For others, environment is a generic term describing a large variety of stakeholders and how these interact and act upon organizations. Organizations and their environment are mutually interdependent and organizational communications are highly affected by the environment. This entry examines the origin...... and development of organization-environment interdependence, the nature of the concept of environment and its relevance for communication scholarships and activities....

  6. Wireless security in mobile health.

    Science.gov (United States)

    Osunmuyiwa, Olufolabi; Ulusoy, Ali Hakan

    2012-12-01

    Mobile health (m-health) is an extremely broad term that embraces mobile communication in the health sector and data packaging. The four broad categories of wireless networks are wireless personal area network, wireless metropolitan area network, wireless wide area network, and wireless local area network. Wireless local area network is the most notable of the wireless networking tools obtainable in the health sector. Transfer of delicate and critical information on radio frequencies should be secure, and the right to use must be meticulous. This article covers the business opportunities in m-health, threats faced by wireless networks in hospitals, and methods of mitigating these threats.

  7. Wireless Emulation Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Wireless Emulation Laboratory (WEL) is a researchtest bed used to investigate fundamental issues in networkscience. It is a research infrastructure that emulates...

  8. Study of LANs access technologies in wind power system

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    2010-01-01

    Due to the energy challenges in the world, new types of generation technologies, such as renewable energy based generators, attract great attention and are being quickly developed, which results in the dramatic developments and changes in modern power systems, the communication technologies play...... a increasingly important role in guaranteeing the power system’s stability, reliability, and security. In this paper the necessity of communication technologies employed in wind power system are introduced. According the International Standards Organization (ISO) reference 7-layered model, the communication...... power environment are explained and discussed. Furthermore the simulation of application of Ethernet in an offshore wind farm communication network by a software, OPNET, is elaborated. With the investigation of the communication technologies in this paper, the offshore wind farm SCADA system can...

  9. Enabling Wireless Avionics Intra-Communications

    Science.gov (United States)

    Torres, Omar; Nguyen, Truong; Mackenzie, Anne

    2016-01-01

    The Electromagnetics and Sensors Branch of NASA Langley Research Center (LaRC) is investigating the potential of an all-wireless aircraft as part of the ECON (Efficient Reconfigurable Cockpit Design and Fleet Operations using Software Intensive, Networked and Wireless Enabled Architecture) seedling proposal, which is funded by the Convergent Aeronautics Solutions (CAS) project, Transformative Aeronautics Concepts (TAC) program, and NASA Aeronautics Research Institute (NARI). The project consists of a brief effort carried out by a small team in the Electromagnetic Environment Effects (E3) laboratory with the intention of exposing some of the challenges faced by a wireless communication system inside the reflective cavity of an aircraft and to explore potential solutions that take advantage of that environment for constructive gain. The research effort was named EWAIC for "Enabling Wireless Aircraft Intra-communications." The E3 laboratory is a research facility that includes three electromagnetic reverberation chambers and equipment that allow testing and generation of test data for the investigation of wireless systems in reflective environments. Using these chambers, the EWAIC team developed a set of tests and setups that allow the intentional variation of intensity of a multipath field to reproduce the environment of the various bays and cabins of large transport aircraft. This setup, in essence, simulates an aircraft environment that allows the investigation and testing of wireless communication protocols that can effectively be used as a tool to mitigate some of the risks inherent to an aircraft wireless system for critical functions. In addition, the EWAIC team initiated the development of a computational modeling tool to illustrate the propagation of EM waves inside the reflective cabins and bays of aircraft and to obtain quantifiable information regarding the degradation of signals in aircraft subassemblies. The nose landing gear of a UAV CAD model was used

  10. A survey on the status of ATM based LAN

    International Nuclear Information System (INIS)

    Yang, Sung Woon; Kang, Soon Ju

    1996-03-01

    This report presents the technical status of the ATM(Asynchronous Transfer Mode) as a new high speed data communication method. Since the FDDI(Fiber optic Distributed Data Interchange) backbone has been installed in september 1995, it has been used as a main network structure of KAERI. However, recently high speed and multimedia data communication environment is being required to accommodate the recent trend of the network usage in KAERI. For example, the rapid growth of Internet usage and increased activities of information retrieval systems on KAERI-Net demand more effective network system. Chapter 1 discusses the status of KAERI-Net and the selection criteria of a network model according to the national plan of super high speed network structure. In Chapter 2, the basic concept of ATM such as communication method and communication structure is studied, and Chapter 3 presents the overall concepts of standard model of ATM. In Chapter 4, we survey the recent trend of technical development of ATM and analyze the status of ATM technology. As a concluding remark, Chapter 5 discusses the criteria and check points for optimal design of KAERI-Net backbone. This report will be used as a technical reference for the installation of ATM in KAERI-Net. 10 tabs., 32 figs., 11 refs. (Author)

  11. Design and Optimisation Problems in Wireless Sensor Networks

    Indian Academy of Sciences (India)

    Premkumar Karumbu,1.05 ECE,,+91-9448227167

    2010-11-14

    Nov 14, 2010 ... Wireless Networks of Multifunction Smart Sensors (WSNs). A smart sensor ... Energy and environment management networks in large buildings. Emerging ISA ... Monitoring mobile patients in hospitals and homes. Locating ...

  12. Internal model control for industrial wireless plant using WirelessHART hardware-in-the-loop simulator.

    Science.gov (United States)

    Tran, Chung Duc; Ibrahim, Rosdiazli; Asirvadam, Vijanth Sagayan; Saad, Nordin; Sabo Miya, Hassan

    2018-04-01

    The emergence of wireless technologies such as WirelessHART and ISA100 Wireless for deployment at industrial process plants has urged the need for research and development in wireless control. This is in view of the fact that the recent application is mainly in monitoring domain due to lack of confidence in control aspect. WirelessHART has an edge over its counterpart as it is based on the successful Wired HART protocol with over 30 million devices as of 2009. Recent works on control have primarily focused on maintaining the traditional PID control structure which is proven not adequate for the wireless environment. In contrast, Internal Model Control (IMC), a promising technique for delay compensation, disturbance rejection and setpoint tracking has not been investigated in the context of WirelessHART. Therefore, this paper discusses the control design using IMC approach with a focus on wireless processes. The simulation and experimental results using real-time WirelessHART hardware-in-the-loop simulator (WH-HILS) indicate that the proposed approach is more robust to delay variation of the network than the PID. Copyright © 2017. Published by Elsevier Ltd.

  13. Portable Integrated Wireless Device Threat Assessment to Aircraft Radio Systems

    Science.gov (United States)

    Salud, Maria Theresa P.; Williams, Reuben A. (Technical Monitor)

    2004-01-01

    An assessment was conducted on multiple wireless local area network (WLAN) devices using the three wireless standards for spurious radiated emissions to determine their threat to aircraft radio navigation systems. The measurement process, data and analysis are provided for devices tested using IEEE 802.11a, IEEE 802.11b, and Bluetooth as well as data from portable laptops/tablet PCs and PDAs (grouping known as PEDs). A comparison was made between wireless LAN devices and portable electronic devices. Spurious radiated emissions were investigated in the radio frequency bands for the following aircraft systems: Instrument Landing System Localizer and Glideslope, Very High Frequency (VHF) Communication, VHF Omnidirectional Range, Traffic Collision Avoidance System, Air Traffic Control Radar Beacon System, Microwave Landing System and Global Positioning System. Since several of the contiguous navigation systems were grouped under one encompassing measurement frequency band, there were five measurement frequency bands where spurious radiated emissions data were collected for the PEDs and WLAN devices. The report also provides a comparison between emissions data and regulatory emission limit.

  14. Marketing de Novos Produtos: Lançamento e Inovação

    Directory of Open Access Journals (Sweden)

    Adriana Conceicao Dutra

    2014-12-01

    Full Text Available Atualmente as empresas lançam um produto com o objetivo de permanecerem por mais tempo no mercado. Embora muitas empresas fracassassem ao lançarem um produto, seria um mito dizer que as maiorias dos novos produtos fracassam ou que seu sucesso vai de acordo com sua atratividade. A modernização traz consigo as premissas, a eficiência, a qualidade e a produtividade, que de certa forma impõem uma carga à sociedade como um todo. Superar as expectativas dos consumidores, por meio de produtos e serviços inovadores, assegura vantagens competitivas e permite às empresas a ocupação de posições de liderança, em mercados altamente competitivos.

  15. A LAN with real-time facilities based on OSI concepts

    International Nuclear Information System (INIS)

    Raaf, A.J. de; Dijkstra, A.; Swierstra, S.D.

    1986-01-01

    Research is being done into structured design and realization methods for Local Area Networks (LAN's). The main aim is to develop a LAN (ZWOLAN) with real-time facilities for use in laboratories and based on ISO-OSI standards. Twentenet will be used for the physical and the data link layer of ZWOLAN. Twentenet is based on a Priority based CSMA/CD data link access mechanism with guaranteed access times. An implementation model has been constructed from an FSM decomposition analysis of OSI protocols. Modular Pascal will be used as language for the realization of the network software. The emphasis is on the software architecture and the reduction of the OSI protocol overhead. (Auth.)

  16. Technology of data transmitting between different data sources based on LAN

    International Nuclear Information System (INIS)

    Zhang Yang; Wang Ling; Chen Yue; Yu Yaowei; Zhang Xiaodong

    2007-01-01

    During experimental operation of EAST, vacuum data and temperature data of inner components should not only be supplied for inner surveillance function of vacuum system, but also be sent by appointed format to database of central control system via LAN of control in real time and by shot document, so that it can supply necessary information for control of plasma discharging and physical analysis. This paper presents how to solves the problem of data communication between EAST vacuum control system and central control system by using OPC function supposed by kingview6.51, Winsock network programming and multithreading technologies. Consequently data transmitting in real-time and by shot document between different data sources within LAN is achieved simultaneously. (authors)

  17. Warming Up to Wireless

    Science.gov (United States)

    Milner, Jacob

    2005-01-01

    In districts big and small across the U.S., students, teachers, and administrators alike have come to appreciate the benefits of wireless technology. Because the technology delivers Internet signals on airborne radio frequencies, wireless networking allows users of all portable devices to move freely on a school's campus and stay connected to the…

  18. Wireless mobile Internet security

    CERN Document Server

    Rhee, Man Young

    2013-01-01

      The mobile industry for wireless cellular services has grown at a rapid pace over the past decade. Similarly, Internet service technology has also made dramatic growth through the World Wide Web with a wire line infrastructure. Realization for complete wired/wireless mobile Internet technologies will become the future objectives for convergence of these technologies thr

  19. Networking issues---Lan and Wan needs---The impact of workstations

    International Nuclear Information System (INIS)

    Harvey, J.

    1990-01-01

    This review focuses on the use of networks in the LEP experiments at CERN. The role of the extended LAN at CERN is discussed in some detail, with particular emphasis on the impact the sudden growth in the use of workstations is having. The problem of network congestion is highlighted and possible evolution to FDDI mentioned. The status and use of the wide area connections are also reported

  20. The effect of sex, slaughter weight and weight gains in PEN-AR-LAN ...

    African Journals Online (AJOL)

    The aim of the study was to determine the effect of sex, body weight and growth rates on basic fattening and slaughter indexes in PEN-AR-LAN fatteners. The research was conducted on 274 PEN-ARLAN hybrid fatteners coming from sows of the Naïma maternal line and was sired by boars of the P-76 meat line. Recorded ...

  1. Fixed Wireless may be a temporary answer

    Indian Academy of Sciences (India)

    Possible to enhance throughput by 4 with respect to Mobile Wireless. And get 8 to 10 bps / Hz / cell; Examples: BB corDECT: today provides 256/512kbps to each connection in fixed environment. Ideal for small town / rural Broadband. Fixed 802.16d/e does the same in but at much higher price-points.

  2. Wireless adiabatic power transfer

    International Nuclear Information System (INIS)

    Rangelov, A.A.; Suchowski, H.; Silberberg, Y.; Vitanov, N.V.

    2011-01-01

    Research highlights: → Efficient and robust mid-range wireless energy transfer between two coils. → The adiabatic energy transfer is analogous to adiabatic passage in quantum optics. → Wireless energy transfer is insensitive to any resonant constraints. → Wireless energy transfer is insensitive to noise in the neighborhood of the coils. - Abstract: We propose a technique for efficient mid-range wireless power transfer between two coils, by adapting the process of adiabatic passage for a coherently driven two-state quantum system to the realm of wireless energy transfer. The proposed technique is shown to be robust to noise, resonant constraints, and other interferences that exist in the neighborhood of the coils.

  3. Certification of biological reference materials: participation of the Neutron Activation Laboratory (LAN-IPEN/CNEN-SP)

    International Nuclear Information System (INIS)

    Ticianelli, Regina B.; Figueiredo, Ana Maria G.

    2007-01-01

    Analytical laboratories have as one of their important goals to demonstrate their competence allowing international acceptance and comparison of analytical data. The IPEN Neutron Activation Laboratory (LAN-IPEN) has implemented its Quality Assurance Program which comprises, among other activities, the participation in intercomparison runs. As a part of this Quality Assurance Program, LAN-IPEN has participated in interlaboratorial trials to analyze two biological candidate reference materials: INCT-CF-3 Corn Flour and INCT-SBF-4 Soya Bean Flour from the Institute of Nuclear Chemistry And Technology (Warszawa, Poland). The elements Br, Ca, Co, Cs, Fe, K, Na, Rb and Zn were analyzed in the candidate reference materials by instrumental neutron activation analysis (INAA). The performance of the laboratory was statistically evaluated in relation to the consensus values for these materials using the Z-Score test. This laboratory evaluation method has been accepted as a standard by ISO/IUPAC. In the present study, adequate Z-Score values (|Z|<2) were observed for all of the analyzed elements, confirming the accuracy of the nuclear methodology employed. The contribution of LAN-IPEN in the certification of the reference materials analyzed was very important, since the results provided were used in the statistical evaluation of the certified value. (author)

  4. Towards Controlling Latency in Wireless Networks

    KAUST Repository

    Bouacida, Nader

    2017-04-24

    , we propose a novel design called “LearnQueue” based on reinforcement learning that can effectively control the latency in wireless networks. LearnQueue adapts quickly and intelligently to changes in the wireless environment using a sophisticated reward structure. Testbed results prove that LearnQueue can guarantee low latency while preserving throughput.

  5. Energy-Harvesting Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon; Vuckovic, Dusan; Di Mauro, Alessio

    2012-01-01

    Energy Harvesting comprises a promising solution to one of the key problems faced by battery-powered Wireless Sensor Networks, namely the limited nature of the energy supply (finite battery capacity). By harvesting energy from the surrounding environment, the sensors can have a continuous lifetime...... Sensor Networks with energy harvesting capability....... without any needs for battery recharge or replacement. However, energy harvesting introduces a change to the fundamental principles based on which WSNs are designed and realized. In this poster we sketch some of the key research challenges as well as our ongoing work in designing and realizing Wireless...

  6. Topology Optimisation of Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Thike Aye Min

    2016-01-01

    Full Text Available Wireless sensor networks are widely used in a variety of fields including industrial environments. In case of a clustered network the location of cluster head affects the reliability of the network operation. Finding of the optimum location of the cluster head, therefore, is critical for the design of a network. This paper discusses the optimisation approach, based on the brute force algorithm, in the context of topology optimisation of a cluster structure centralised wireless sensor network. Two examples are given to verify the approach that demonstrate the implementation of the brute force algorithm to find an optimum location of the cluster head.

  7. NASA Lunar Base Wireless System Propagation Analysis

    Science.gov (United States)

    Hwu, Shian U.; Upanavage, Matthew; Sham, Catherine C.

    2007-01-01

    There have been many radio wave propagation studies using both experimental and theoretical techniques over the recent years. However, most of studies have been in support of commercial cellular phone wireless applications. The signal frequencies are mostly at the commercial cellular and Personal Communications Service bands. The antenna configurations are mostly one on a high tower and one near the ground to simulate communications between a cellular base station and a mobile unit. There are great interests in wireless communication and sensor systems for NASA lunar missions because of the emerging importance of establishing permanent lunar human exploration bases. Because of the specific lunar terrain geometries and RF frequencies of interest to the NASA missions, much of the published literature for the commercial cellular and PCS bands of 900 and 1800 MHz may not be directly applicable to the lunar base wireless system and environment. There are various communication and sensor configurations required to support all elements of a lunar base. For example, the communications between astronauts, between astronauts and the lunar vehicles, between lunar vehicles and satellites on the lunar orbits. There are also various wireless sensor systems among scientific, experimental sensors and data collection ground stations. This presentation illustrates the propagation analysis of the lunar wireless communication and sensor systems taking into account the three dimensional terrain multipath effects. It is observed that the propagation characteristics are significantly affected by the presence of the lunar terrain. The obtained results indicate the lunar surface material, terrain geometry and antenna location are the important factors affecting the propagation characteristics of the lunar wireless systems. The path loss can be much more severe than the free space propagation and is greatly affected by the antenna height, surface material and operating frequency. The

  8. Research on Matrix-type Packet Loss Compensation Scheme for Wireless Video Transmission on Subway

    Directory of Open Access Journals (Sweden)

    Fan Qing-Wu

    2017-01-01

    Full Text Available As the mainstream wireless LAN technology, Wi-Fi can achieve fast data transfer. With the subway moving in a high speed, video data transmission between the metro and the ground is achieved through Wi-Fi technology. This paper aims at solving the Caton problem caused by switching packet loss in the process of playing real-time video on the train terminal, and proposes matrix-type packet loss compensation scheme. Finally, the feasibility of the scheme is verified by experiments.

  9. Development of a Testbed for Wireless Underground Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mehmet C. Vuran

    2010-01-01

    Full Text Available Wireless Underground Sensor Networks (WUSNs constitute one of the promising application areas of the recently developed wireless sensor networking techniques. WUSN is a specialized kind of Wireless Sensor Network (WSN that mainly focuses on the use of sensors that communicate through soil. Recent models for the wireless underground communication channel are proposed but few field experiments were realized to verify the accuracy of the models. The realization of field WUSN experiments proved to be extremely complex and time-consuming in comparison with the traditional wireless environment. To the best of our knowledge, this is the first work that proposes guidelines for the development of an outdoor WUSN testbed with the goals of improving the accuracy and reducing of time for WUSN experiments. Although the work mainly aims WUSNs, many of the presented practices can also be applied to generic WSN testbeds.

  10. Security for multihop wireless networks

    CERN Document Server

    Khan, Shafiullah

    2014-01-01

    Security for Multihop Wireless Networks provides broad coverage of the security issues facing multihop wireless networks. Presenting the work of a different group of expert contributors in each chapter, it explores security in mobile ad hoc networks, wireless sensor networks, wireless mesh networks, and personal area networks.Detailing technologies and processes that can help you secure your wireless networks, the book covers cryptographic coprocessors, encryption, authentication, key management, attacks and countermeasures, secure routing, secure medium access control, intrusion detection, ep

  11. The wireless internet explained

    CERN Document Server

    Rhoton, John

    2001-01-01

    The Wireless Internet Explained covers the full spectrum of wireless technologies from a wide range of vendors, including initiatives by Microsoft and Compaq. The Wireless Internet Explained takes a practical look at wireless technology. Rhoton explains the concepts behind the physics, and provides an overview that clarifies the convoluted set of standards heaped together under the umbrella of wireless. It then expands on these technical foundations to give a panorama of the increasingly crowded landscape of wireless product offerings. When it comes to actual implementation the book gives abundant down-to-earth advice on topics ranging from the selection and deployment of mobile devices to the extremely sensitive subject of security.Written by an expert on Internet messaging, the author of Digital Press''s successful Programmer''s Guide to Internet Mail and X.400 and SMTP: Battle of the E-mail Protocols, The Wireless Internet Explained describes and evaluates the current state of the fast-growing and crucial...

  12. Battling Latency in Modern Wireless Networks

    KAUST Repository

    Showail, Ahmad

    2018-05-15

    Buffer sizing has a tremendous effect on the performance of Wi-Fi based networks. Choosing the right buffer size is challenging due to the dynamic nature of the wireless environment. Over buffering or ‘bufferbloat’ may produce unacceptable endto-end delays. On the other hand, small buffers may limit the performance gains that can be obtained with various IEEE 802.11n/ac enhancements, such as frame aggregation. We propose Wireless Queue Management (WQM), a novel, practical, and lightweight queue management scheme for wireless networks. WQM adapts the buffer size based on the wireless link characteristics and the network load. Furthermore, it accounts for aggregates length when deciding on the optimal buffer size. We evaluate WQM using our 10 nodes wireless testbed. WQM reduces the end-to-end delay by an order of magnitude compared to the default buffer size in Linux while achieving similar network throughput. Also, WQM outperforms state of the art bufferbloat solutions, namely CoDel and PIE. WQM achieves 7× less latency compared to PIE, and 2× compared to CoDel at the cost of 8% drop in goodput in the worst case. Further, WQM improves network fairness as it limits the ability of a single flow to saturate the buffers.

  13. Battling Latency in Modern Wireless Networks

    KAUST Repository

    Showail, Ahmad; Shihada, Basem

    2018-01-01

    Buffer sizing has a tremendous effect on the performance of Wi-Fi based networks. Choosing the right buffer size is challenging due to the dynamic nature of the wireless environment. Over buffering or ‘bufferbloat’ may produce unacceptable endto-end delays. On the other hand, small buffers may limit the performance gains that can be obtained with various IEEE 802.11n/ac enhancements, such as frame aggregation. We propose Wireless Queue Management (WQM), a novel, practical, and lightweight queue management scheme for wireless networks. WQM adapts the buffer size based on the wireless link characteristics and the network load. Furthermore, it accounts for aggregates length when deciding on the optimal buffer size. We evaluate WQM using our 10 nodes wireless testbed. WQM reduces the end-to-end delay by an order of magnitude compared to the default buffer size in Linux while achieving similar network throughput. Also, WQM outperforms state of the art bufferbloat solutions, namely CoDel and PIE. WQM achieves 7× less latency compared to PIE, and 2× compared to CoDel at the cost of 8% drop in goodput in the worst case. Further, WQM improves network fairness as it limits the ability of a single flow to saturate the buffers.

  14. Techniques for Wireless Applications

    KAUST Repository

    Gaaloul, Fakhreddine

    2012-05-01

    Switching techniques have been first proposed as a spacial diversity techniques. These techniques have been shown to reduce considerably the processing load while letting multi-antenna systems achieve a specific target performance. In this thesis, we take a different look at the switching schemes by implementing them for different other wireless applications. More specifically, this thesis consists of three main parts, where the first part considers a multiuser environment and an adaptive scheduling algorithm based on the switching with post-selection scheme for statistically independent but non-identically distributed channel conditions. The performance of this switched based scheduler is investigated and a multitude of performance metrics are presented. In a second part, we propose and analyze the performance of three switched-based algorithms for interference reduction in the downlink of over-loaded femtocells. For instance, performance metrics are derived in closed-form and these metrics are used to compare these three proposed schemes. Finally in a third part, a switch based opportunistic channel access scheme is proposed for a cognitive radio system and its performance is analyzed in terms of two new proposed metrics namely the average cognitive radio access and the waiting time duration.

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

    KAUST Repository

    Showail, Ahmad

    2014-04-06

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

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

    KAUST Repository

    Showail, Ahmad; Jamshaid, Kamran; Shihada, Basem

    2014-01-01

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

  17. Detection of Spoofed MAC Addresses in 802.11 Wireless Networks

    Science.gov (United States)

    Tao, Kai; Li, Jing; Sampalli, Srinivas

    Medium Access Control (MAC) address spoofing is considered as an important first step in a hacker's attempt to launch a variety of attacks on 802.11 wireless networks. Unfortunately, MAC address spoofing is hard to detect. Most current spoofing detection systems mainly use the sequence number (SN) tracking technique, which has drawbacks. Firstly, it may lead to an increase in the number of false positives. Secondly, such techniques cannot be used in systems with wireless cards that do not follow standard 802.11 sequence number patterns. Thirdly, attackers can forge sequence numbers, thereby causing the attacks to go undetected. We present a new architecture called WISE GUARD (Wireless Security Guard) for detection of MAC address spoofing on 802.11 wireless LANs. It integrates three detection techniques - SN tracking, Operating System (OS) fingerprinting & tracking and Received Signal Strength (RSS) fingerprinting & tracking. It also includes the fingerprinting of Access Point (AP) parameters as an extension to the OS fingerprinting for detection of AP address spoofing. We have implemented WISE GUARD on a test bed using off-the-shelf wireless devices and open source drivers. Experimental results show that the new design enhances the detection effectiveness and reduces the number of false positives in comparison with current approaches.

  18. Wireless Power Supply via Coupled Magnetic Resonance for on-line Monitoring Wireless Sensor of High-voltage Electrical Equipment

    DEFF Research Database (Denmark)

    Xingkui, Mao; Qisheng, Huang; Yudi, Xiao

    2016-01-01

    On-line monitoring of high-voltage electrical equipment (HV-EE) aiming to detect faults effectively has become crucial to avoid serious accidents. Moreover, highly reliable power supplies are the key component for the wireless sensors equipped in such on-line monitoring systems. Therefore......, in this paper, the wireless power supply via coupled magnetic resonance (MR-WPS) is proposed for powering the wireless sensor and the associated wireless sensor solution is also proposed. The key specifications of the MR-WPS working in switchgear cabinet with a harsh operation environment are analyzed...... power is able to be delivered to the wireless sensor through the designed MR-WPS, and therefore the theoretical analysis and design is verified....

  19. Securing wireless communications at the physical layer

    CERN Document Server

    Liu, Ruoheng

    2009-01-01

    Throughout this book there is an underlying theme that the rich multipath environment that is typical of wireless scenarios supports the establishment of new security services at the physical layer, including new mechanisms that establish cryptographic keys, that support communication with assured confidentiality, and that can authenticate transmitters in mobile environments. The book takes a holistic approach to covering topics related to physical layer security solutions, with contributions ranging from the theoretical underpinnings behind secure communications to practical systems validatio

  20. Wireless rechargeable sensor networks

    CERN Document Server

    Yang, Yuanyuan

    2015-01-01

    This SpringerBrief provides a concise guide to applying wireless energy transfer techniques in traditional battery-powered sensor networks. It examines the benefits and challenges of wireless power including efficiency and reliability. The authors build a wireless rechargeable sensor networks from scratch and aim to provide perpetual network operation. Chapters cover a wide range of topics from the collection of energy information and recharge scheduling to joint design with typical sensing applications such as data gathering. Problems are approached using a natural combination of probability

  1. Wireless network pricing

    CERN Document Server

    Huang, Jianwei

    2013-01-01

    Today's wireless communications and networking practices are tightly coupled with economic considerations, to the extent that it is almost impossible to make a sound technology choice without understanding the corresponding economic implications. This book aims at providing a foundational introduction on how microeconomics, and pricing theory in particular, can help us to understand and build better wireless networks. The book can be used as lecture notes for a course in the field of network economics, or a reference book for wireless engineers and applied economists to understand how pricing

  2. Wireless networks of opportunity in support of secure field operations

    Science.gov (United States)

    Stehle, Roy H.; Lewis, Mark

    1997-02-01

    Under funding from the Defense Advanced Research Projects Agency (DARPA) for joint military and law enforcement technologies, demonstrations of secure information transfer in support of law enforcement and military operations other than war, using wireless and wired technology, were held in September 1996 at several locations in the United States. In this paper, the network architecture, protocols, and equipment supporting the demonstration's scenarios are presented, together with initial results, including lessons learned and desired system enhancements. Wireless networks of opportunity encompassed in-building (wireless-LAN), campus-wide (Metricom Inc.), metropolitan (AMPS cellular, CDPD), and national (one- and two-way satellite) systems. Evolving DARPA-sponsored packet radio technology was incorporated. All data was encrypted, using multilevel information system security initiative (MISSI)FORTEZZA technology, for carriage over unsecured and unclassified commercial networks. The identification and authentication process inherent in the security system permitted logging for database accesses and provided an audit trail useful in evidence gathering. Wireless and wireline communications support, to and between modeled crisis management centers, was demonstrated. Mechanisms for the guarded transport of data through the secret-high military tactical Internet were included, to support joint law enforcement and crisis management missions. A secure World Wide Web (WWW) browser forms the primary, user-friendly interface for information retrieval and submission. The WWW pages were structured to be sensitive to the bandwidth, error rate, and cost of the communications medium in use (e.g., the use of and resolution for graphical data). Both still and motion compressed video were demonstrated, along with secure voice transmission from laptop computers in the field. Issues of network bandwidth, airtime costs, and deployment status are discussed.

  3. Green heterogeneous wireless networks

    CERN Document Server

    Ismail, Muhammad; Nee, Hans-Peter; Qaraqe, Khalid A; Serpedin, Erchin

    2016-01-01

    This book focuses on the emerging research topic "green (energy efficient) wireless networks" which has drawn huge attention recently from both academia and industry. This topic is highly motivated due to important environmental, financial, and quality-of-experience (QoE) considerations. Specifically, the high energy consumption of the wireless networks manifests in approximately 2% of all CO2 emissions worldwide. This book presents the authors’ visions and solutions for deployment of energy efficient (green) heterogeneous wireless communication networks. The book consists of three major parts. The first part provides an introduction to the "green networks" concept, the second part targets the green multi-homing resource allocation problem, and the third chapter presents a novel deployment of device-to-device (D2D) communications and its successful integration in Heterogeneous Networks (HetNets). The book is novel in that it specifically targets green networking in a heterogeneous wireless medium, which re...

  4. Wireless radio a history

    CERN Document Server

    Coe, Lewis

    2006-01-01

    ""Informative...recommended""--Choice; ""interesting...a good read...well worth reading""--Contact Magazine. This history first looks at Marconi's wireless communications system and then explores its many applications, including marine radio, cellular telephones, police and military uses, television and radar. Radio collecting is also discussed, and brief biographies are provided for the major figures in the development and use of the wireless.

  5. A Fuzzy Preprocessing Module for Optimizing the Access Network Selection in Wireless Networks

    Directory of Open Access Journals (Sweden)

    Faisal Kaleem

    2013-01-01

    Full Text Available A heterogeneous wireless network is characterized by the presence of different wireless access technologies that coexist in an overlay fashion. These wireless access technologies usually differ in terms of their operating parameters. On the other hand, Mobile Stations (MSs in a heterogeneous wireless network are equipped with multiple interfaces to access different types of services from these wireless access technologies. The ultimate goal of these heterogeneous wireless networks is to provide global connectivity with efficient ubiquitous computing to these MSs based on the Always Best Connected (ABC principle. This is where the need for intelligent and efficient Vertical Handoffs (VHOs between wireless technologies in a heterogeneous environment becomes apparent. This paper presents the design and implementation of a fuzzy multicriteria based Vertical Handoff Necessity Estimation (VHONE scheme that determines the proper time for VHO, while considering the continuity and quality of the currently utilized service, and the end-users' satisfaction.

  6. First results from the MuLan and MuCap experiments

    International Nuclear Information System (INIS)

    Banks, T. I.

    2008-01-01

    MuLan and MuCap are ongoing experiments at the Paul Scherrer Institut, Switzerland, that use the muon lifetime to determine fundamental weak interaction parameters. The goal of MuLan is a 1 ppm measurement of the positive muon lifetime τ μ + to determine the Fermi constant G F to 0.5 ppm. The goal of MuCap is to make a 1% determination of the rate Λ S of the process of nuclear muon capture by the proton, μp→nν, by measuring the μ - disappearance rate in hydrogen gas to 10 ppm and subtracting the world average for the μ + decay rate. A 1% determination of the capture rate Λ S is of interest because it would enable a 7% determination of g P , the induced pseudoscalar coupling of the nucleon. In 2007, both experiments published first results based upon data collected by each in 2004. MuLan reported an 11 ppm μ + lifetime measurement, τ μ + = 2.197 013(24) μs, resulting in a new, 9.6 ppm world average, τ μ + = 2.197 019(21) μs, which determines the Fermi constant, G F = 1.166 371(6)x10 -5 GeV -2 , to 5 ppm. MuCap reported a 3% measurement of the muon capture rate from the hyperfine singlet ground state of the μp atom, Λ S = 725.0±17.4 s -1 , from which a 15% value for the pseudoscalar coupling, g P (q 2 = -0.88m μ 2 ) = 7.3±1.1, was extracted

  7. First results from the MuLan and MuCap experiments

    Science.gov (United States)

    Banks, T. I.

    2008-02-01

    MuLan and MuCap are ongoing experiments at the Paul Scherrer Institut, Switzerland, that use the muon lifetime to determine fundamental weak interaction parameters. The goal of MuLan is a 1 ppm measurement of the positive muon lifetime τμ+ to determine the Fermi constant GF to 0.5 ppm. The goal of MuCap is to make a 1% determination of the rate ΛS of the process of nuclear muon capture by the proton, μp→nν, by measuring the μ- disappearance rate in hydrogen gas to 10 ppm and subtracting the world average for the μ+ decay rate. A 1% determination of the capture rate ΛS is of interest because it would enable a 7% determination of gP, the induced pseudoscalar coupling of the nucleon. In 2007, both experiments published first results based upon data collected by each in 2004. MuLan reported an 11 ppm μ+ lifetime measurement, τμ+ = 2.197 013(24) μs, resulting in a new, 9.6 ppm world average, τμ+ = 2.197 019(21) μs, which determines the Fermi constant, GF = 1.166 371(6)×10-5 GeV-2, to 5 ppm. MuCap reported a 3% measurement of the muon capture rate from the hyperfine singlet ground state of the μp atom, ΛS = 725.0±17.4 s-1, from which a 15% value for the pseudoscalar coupling, gP(q2 = -0.88mμ2) = 7.3±1.1, was extracted.

  8. Wireless Networks: New Meaning to Ubiquitous Computing.

    Science.gov (United States)

    Drew, Wilfred, Jr.

    2003-01-01

    Discusses the use of wireless technology in academic libraries. Topics include wireless networks; standards (IEEE 802.11); wired versus wireless; why libraries implement wireless technology; wireless local area networks (WLANs); WLAN security; examples of wireless use at Indiana State University and Morrisville College (New York); and useful…

  9. Optical wireless connected objects for healthcare.

    Science.gov (United States)

    Toumieux, Pascal; Chevalier, Ludovic; Sahuguède, Stéphanie; Julien-Vergonjanne, Anne

    2015-10-01

    In this Letter the authors explore the communication capabilities of optical wireless technology for a wearable device dedicated to healthcare application. In an indoor environment sensible to electromagnetic perturbations such as a hospital, the use of optical wireless links can permit reducing the amount of radio frequencies in the patient environment. Moreover, this technology presents the advantage to be secure, low-cost and easy to deploy. On the basis of commercially available components, a custom-made wearable device is presented, which allows optical wireless transmission of accelerometer data in the context of physical activity supervision of post-stroke patients in hospital. Considering patient mobility, the experimental performance is established in terms of packet loss as a function of the number of receivers fixed to the ceiling. The results permit to conclude that optical wireless links can be used to perform such mobile remote monitoring applications. Moreover, based on the measurements obtained with one receiver, it is possible to theoretically determine the performance according to the number of receivers to be deployed.

  10. Impact of wireless communication on multimedia application performance

    Science.gov (United States)

    Brown, Kevin A.

    1999-01-01

    Multimedia applications and specifically voice and video conferencing tools are widely used in business communications, and are quickly being discovered by the consumer market as well. At the same time, wireless communication services such as PCS voice and cellular data are becoming very popular, leading to the desire to deploy multimedia applications in the wireless environment. Wireless links, however, exhibit several characteristics which are different from traditional wired networks. These include: dynamically changing bandwidth due to mobile host movement in and out of cell where bandwidth is shared, high rates of packet corruption and subsequent loss, and frequent are lengthy disconnections due to obstacles, fading, and movement between cells. In addition, these effects are short-lived and difficult to reproduce, leading to a lack of adequate testing and analysis for applications used in wireless environments.

  11. A Review of Various Security Protocols in Wireless Sensor Network

    OpenAIRE

    Anupma Sangwan; Deepti Sindhu; Kulbir Singh

    2011-01-01

    Sensor networks are highly distributed networks of small, lightweight wireless sensor nodes, deployed in large numbers to monitor the environment or system by the measurement of physical parameters such as temperature, pressure, or relative humidity, sound, vibration, motion or pollutants, at different locations. A WSN [1] is composed of a large number of low-cost sensor nodes (SNs) and one or several base stations (BS) or destination nodes. SNs are typically small wireless devices with limit...

  12. Broadband and High power Reactive Jamming Resilient Wireless Communication

    Science.gov (United States)

    2017-10-21

    Broadband and High -power Reactive Jamming Resilient Wireless Communication The views, opinions and/or findings contained in this report are those of... available in extremely hostile environments, where FHSS and DSSS are completely defeated by a broadband and high -power reactive jammer. b. Wireless...SECURITY CLASSIFICATION OF: 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY NOTES 12. DISTRIBUTION AVAILIBILITY STATEMENT 6. AUTHORS

  13. Coverage and Connectivity Issue in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Rachit Trivedi

    2013-04-01

    Full Text Available Wireless sensor networks (WSNs are an emerging area of interest in research and development. It finds use in military surveillance, health care, environmental monitoring, forest fire detection and smart environments. An important research issue in WSNs is the coverage since cost, area and lifetime are directly validated to it.In this paper we present an overview of WSNs and try to refine the coverage and connectivity issues in wireless sensor networks.

  14. Evolution of Heterogeneous Wireless Networks

    DEFF Research Database (Denmark)

    Zhang, Q.; Fitzek, Frank; Katz, Marcos

    2006-01-01

    Mobile and wireless content, services and networks - Short-term and long-term development trends......Mobile and wireless content, services and networks - Short-term and long-term development trends...

  15. The relationship between a deformation-based eddy parameterization and the LANS-α turbulence model

    Science.gov (United States)

    Bachman, Scott D.; Anstey, James A.; Zanna, Laure

    2018-06-01

    A recent class of ocean eddy parameterizations proposed by Porta Mana and Zanna (2014) and Anstey and Zanna (2017) modeled the large-scale flow as a non-Newtonian fluid whose subgridscale eddy stress is a nonlinear function of the deformation. This idea, while largely new to ocean modeling, has a history in turbulence modeling dating at least back to Rivlin (1957). The new class of parameterizations results in equations that resemble the Lagrangian-averaged Navier-Stokes-α model (LANS-α, e.g., Holm et al., 1998a). In this note we employ basic tensor mathematics to highlight the similarities between these turbulence models using component-free notation. We extend the Anstey and Zanna (2017) parameterization, which was originally presented in 2D, to 3D, and derive variants of this closure that arise when the full non-Newtonian stress tensor is used. Despite the mathematical similarities between the non-Newtonian and LANS-α models which might provide insight into numerical implementation, the input and dissipation of kinetic energy between these two turbulent models differ.

  16. Extending the Capabilities of Closed-loop Distributed Engine Control Simulations Using LAN Communication

    Science.gov (United States)

    Aretskin-Hariton, Eliot D.; Zinnecker, Alicia Mae; Culley, Dennis E.

    2014-01-01

    Distributed Engine Control (DEC) is an enabling technology that has the potential to advance the state-of-the-art in gas turbine engine control. To analyze the capabilities that DEC offers, a Hardware-In-the-Loop (HIL) test bed is being developed at NASA Glenn Research Center. This test bed will support a systems-level analysis of control capabilities in closed-loop engine simulations. The structure of the HIL emulates a virtual test cell by implementing the operator functions, control system, and engine on three separate computers. This implementation increases the flexibility and extensibility of the HIL. Here, a method is discussed for implementing these interfaces by connecting the three platforms over a dedicated Local Area Network (LAN). This approach is verified using the Commercial Modular Aero-Propulsion System Simulation 40k (C-MAPSS40k), which is typically implemented on one computer. There are marginal differences between the results from simulation of the typical and the three-computer implementation. Additional analysis of the LAN network, including characterization of network load, packet drop, and latency, is presented. The three-computer setup supports the incorporation of complex control models and proprietary engine models into the HIL framework.

  17. KİRLİ SULARLA SULAMA YAPlLAN TOPRAKLARDA MİKROBİYAL KİRLENME

    Directory of Open Access Journals (Sweden)

    KENAN TUNÇ

    2005-01-01

    Full Text Available Bu çalışmada Kocaeli İli Derince İlçesine bağlı 11�ıu Köyü Bölgesi'nde Nisan - Mayıs 2003 ayları asında kirli sularla sulama yapılan ekili alanlarda bakteriolojik kirlilik araştırması yapılmıştır. ra�tırmamızda Slıigella (2050, E.�clıericlıia coli (1 0000, Enterobcıcter (10000 olmak üzere toplam 2�050 ba kteri gözlenmiştir. Aynı bölgedeki temiz sularda Sizige/la (50, Esclıericlıia coli görülmemiş, Enterobacter ise (300 olarak tespit edilmiştir. raştırmaınııda kirli sularta sulama yapılan ekili a l anlarda insan sağlığı üzerinde potansiyel risk oltı�turan ba kteriyoloj ik llt;.irliliğin olduğu gözlenmiştir. r Keliı11eler - Slıigella, Esclıericlıia co

  18. OPTICAL WIRELESS COMMUNICATION SYSTEM

    Directory of Open Access Journals (Sweden)

    JOSHUA L.Y. CHIENG

    2016-02-01

    Full Text Available The growing demand of bandwidth in this modern internet age has been testing the existing telecommunication infrastructures around the world. With broadband speeds moving towards the region of Gbps and Tbps, many researches have begun on the development of using optical wireless technology as feasible and future methods to the current wireless technology. Unlike the existing radio frequency wireless applications, optical wireless uses electromagnetic spectrums that are unlicensed and free. With that, this project aim to understand and gain better understanding of optical wireless communication system by building an experimental and simulated model. The quality of service and system performance will be investigated and reviewed. This project employs laser diode as the propagation medium and successfully transferred audio signals as far as 15 meters. On its quality of service, results of the project model reveal that the bit error rate increases, signal-to-noise ratio and quality factor decreases as the link distance between the transmitter and receiver increases. OptiSystem was used to build the simulated model and MATLAB was used to assist signal-to-noise ratio calculations. By comparing the simulated and experimental receiver’s power output, the experimental model’s efficiency is at 66.3%. Other than the system’s performance, challenges and factors affecting the system have been investigated and discussed. Such challenges include beam divergence, misalignment and particle absorption.

  19. Robust Controller for Delays and Packet Dropout Avoidance in Solar-Power Wireless Network

    OpenAIRE

    Al-Azzawi, Waleed

    2013-01-01

    Solar Wireless Networked Control Systems (SWNCS) are a style of distributed control systems where sensors, actuators, and controllers are interconnected via a wireless communication network. This system setup has the benefit of low cost, flexibility, low weight, no wiring and simplicity of system diagnoses and maintenance. However, it also unavoidably calls some wireless network time delays and packet dropout into the design procedure. Solar lighting system offers a clean environment, therefo...

  20. Coherently Enhanced Wireless Power Transfer

    Science.gov (United States)

    Krasnok, Alex; Baranov, Denis G.; Generalov, Andrey; Li, Sergey; Alù, Andrea

    2018-04-01

    Extraction of electromagnetic energy by an antenna from impinging external radiation is at the basis of wireless communications and wireless power transfer (WPT). The maximum of transferred energy is ensured when the antenna is conjugately matched, i.e., when it is resonant and it has an equal coupling with free space and its load. This condition, however, can be easily affected by changes in the environment, preventing optimal operation of a WPT system. Here, we introduce the concept of coherently enhanced WPT that allows us to bypass this difficulty and achieve dynamic control of power transfer. The approach relies on coherent excitation of the waveguide connected to the antenna load with a backward propagating signal of specific amplitude and phase. This signal creates a suitable interference pattern at the load resulting in a modification of the local wave impedance, which in turn enables conjugate matching and a largely increased amount of extracted energy. We develop a simple theoretical model describing this concept, demonstrate it with full-wave numerical simulations for the canonical example of a dipole antenna, and verify experimentally in both near-field and far-field regimes.

  1. Wireless Augmented Reality Prototype (WARP)

    Science.gov (United States)

    Devereaux, A. S.

    1999-01-01

    Initiated in January, 1997, under NASA's Office of Life and Microgravity Sciences and Applications, the Wireless Augmented Reality Prototype (WARP) is a means to leverage recent advances in communications, displays, imaging sensors, biosensors, voice recognition and microelectronics to develop a hands-free, tetherless system capable of real-time personal display and control of computer system resources. Using WARP, an astronaut may efficiently operate and monitor any computer-controllable activity inside or outside the vehicle or station. The WARP concept is a lightweight, unobtrusive heads-up display with a wireless wearable control unit. Connectivity to the external system is achieved through a high-rate radio link from the WARP personal unit to a base station unit installed into any system PC. The radio link has been specially engineered to operate within the high- interference, high-multipath environment of a space shuttle or space station module. Through this virtual terminal, the astronaut will be able to view and manipulate imagery, text or video, using voice commands to control the terminal operations. WARP's hands-free access to computer-based instruction texts, diagrams and checklists replaces juggling manuals and clipboards, and tetherless computer system access allows free motion throughout a cabin while monitoring and operating equipment.

  2. Wireless infrared indoor communications: how to combat the multipath distortion

    Science.gov (United States)

    Jivkova, Svetla T.; Kavehrad, Mohsen

    2001-02-01

    12 Currently, higher and higher transmission speeds are being pursuit for wireless LANs. The present investigation deals with one of the most prospective candidates for high-speed in-house wireless communications, namely, Multi-Spot Diffusing Configuration (MSDC). Since it uses optical medium for data transmission, it possesses inherent potential for achieving very high capacity level. Channel characteristics in MSDC are simulated and the causes for channel distortion are analyzed. Then, conditions for creation of a virtually ideal channel are derived. It is shown that the 3 dB-channel bandwidth can be extended up to frequencies beyond 2 GHz. The large bandwidth comes at the cost of poor power efficiency. In order to compensate for this, a novel receiver optical front-end design is proposed and its performance is analyzed. Taking advantage of unique properties of holographic optical elements, conventional optical front-end consisting of a concentrator and a filter, is replaced by a single holographic curved mirror. Utilization of such a holographic optical element improves the signal-to-shot noise ratio by up to 18.5 dB.

  3. Wireless networking for the dental office: current wireless standards and security protocols.

    Science.gov (United States)

    Mupparapu, Muralidhar; Arora, Sarika

    2004-11-15

    Digital radiography has gained immense popularity in dentistry today in spite of the early difficulty for the profession to embrace the technology. The transition from film to digital has been happening at a faster pace in the fields of Orthodontics, Oral Surgery, Endodontics, Periodontics, and other specialties where the radiographic images (periapical, bitewing, panoramic, cephalometric, and skull radiographs) are being acquired digitally, stored within a server locally, and eventually accessed for diagnostic purposes, along with the rest of the patient data via the patient management software (PMS). A review of the literature shows the diagnostic performance of digital radiography is at least comparable to or even better than that of conventional radiography. Similarly, other digital diagnostic tools like caries detectors, cephalometric analysis software, and digital scanners were used for many years for the diagnosis and treatment planning purposes. The introduction of wireless charged-coupled device (CCD) sensors in early 2004 (Schick Technologies, Long Island City, NY) has moved digital radiography a step further into the wireless era. As with any emerging technology, there are concerns that should be looked into before adapting to the wireless environment. Foremost is the network security involved in the installation and usage of these wireless networks. This article deals with the existing standards and choices in wireless technologies that are available for implementation within a contemporary dental office. The network security protocols that protect the patient data and boost the efficiency of modern day dental clinics are enumerated.

  4. Wireless communications resource management

    CERN Document Server

    Lee, B; Seo, H

    2009-01-01

    Wireless technologies continue to evolve to address the insatiable demand for faster response times, larger bandwidth, and reliable transmission. Yet as the industry moves toward the development of post 3G systems, engineers have consumed all the affordable physical layer technologies discovered to date. This has necessitated more intelligent and optimized utilization of available wireless resources. Wireless Communications Resource Managem ent, Lee, Park, and Seo cover all aspects of this critical topic, from the preliminary concepts and mathematical tools to detailed descriptions of all the resource management techniques. Readers will be able to more effectively leverage limited spectrum and maximize device battery power, as well as address channel loss, shadowing, and multipath fading phenomena.

  5. Wireless physical layer security

    Science.gov (United States)

    Poor, H. Vincent; Schaefer, Rafael F.

    2017-01-01

    Security in wireless networks has traditionally been considered to be an issue to be addressed separately from the physical radio transmission aspects of wireless systems. However, with the emergence of new networking architectures that are not amenable to traditional methods of secure communication such as data encryption, there has been an increase in interest in the potential of the physical properties of the radio channel itself to provide communications security. Information theory provides a natural framework for the study of this issue, and there has been considerable recent research devoted to using this framework to develop a greater understanding of the fundamental ability of the so-called physical layer to provide security in wireless networks. Moreover, this approach is also suggestive in many cases of coding techniques that can approach fundamental limits in practice and of techniques for other security tasks such as authentication. This paper provides an overview of these developments.

  6. Radiation area monitoring by wireless-communicating area monitor with surveillance camera

    International Nuclear Information System (INIS)

    Shimura, Mitsuo; Kobayashi, Hiromitsu; Kitahara, Hideki; Kobayashi, Hironobu; Okamoto, Shinji

    2004-01-01

    Aiming at a dose reduction and a work efficiency improvement for nuclear power plants that have high dose regions, we have developed our system of wireless-communicating Area Monitor with Surveillance Camera, and have performed an on-site test. Now we are implementing this Area Monitor with Surveillance Camera for a use as a TV camera in the controlled-area, which enables a personal computer to simultaneously display two or more dose values and site live images on the screen. For the radiation detector of this Area Monitor System, our wireless-communicating dosimeter is utilized. Image data are transmitted via a wireless Local Area Network (LAN). As a test result, image transmission of a maximum of 20 frames per second has been realized, which shows that this concept is a practical application. Remote-site monitoring also has been realized from an office desk located within the non-controlled area, adopting a Japan's wireless phone system, PHS (Personal Handy Phone) for the transmission interface. (author)

  7. Terabit Wireless Communication Challenges

    Science.gov (United States)

    Hwu, Shian U.

    2012-01-01

    This presentation briefly discusses a research effort on Terabit Wireless communication systems for possible space applications. Recently, terahertz (THz) technology (300-3000 GHz frequency) has attracted a great deal of interest from academia and industry. This is due to a number of interesting features of THz waves, including the nearly unlimited bandwidths available, and the non-ionizing radiation nature which does not damage human tissues and DNA with minimum health threat. Also, as millimeter-wave communication systems mature, the focus of research is, naturally, moving to the THz range. Many scientists regard THz as the last great frontier of the electromagnetic spectrum, but finding new applications outside the traditional niches of radio astronomy, Earth and planetary remote sensing, and molecular spectroscopy particularly in biomedical imaging and wireless communications has been relatively slow. Radiologists find this area of study so attractive because t-rays are non-ionizing, which suggests no harm is done to tissue or DNA. They also offer the possibility of performing spectroscopic measurements over a very wide frequency range, and can even capture signatures from liquids and solids. According to Shannon theory, the broad bandwidth of the THz frequency bands can be used for terabit-per-second (Tb/s) wireless communication systems. This enables several new applications, such as cell phones with 360 degrees autostereoscopic displays, optic-fiber replacement, and wireless Tb/s file transferring. Although THz technology could satisfy the demand for an extremely high data rate, a number of technical challenges need to be overcome before its development. This presentation provides an overview the state-of-the- art in THz wireless communication and the technical challenges for an emerging application in Terabit wireless systems. The main issue for THz wave propagation is the high atmospheric attenuation, which is dominated by water vapor absorption in the THz

  8. Advanced routing protocols for wireless networks

    CERN Document Server

    Campista , Miguel Elias Mitre

    2014-01-01

    This text introduces the principles of routing protocols and metrics as they affect wireless networking environments, specifically in urban areas. Timely because of the recent rise in small city life, this topic includes the consideration of ad hoc, mesh, vehicular, sensor, and delay tolerant networks. These approaches are each unique, and author Miguel Mitre Campista provides a thorough, but accessible, explanation of their individual characteristics for engineers, computer scientists, IT professionals, and curious Internet users.

  9. Towards Self-Powered Wireless Sensor Networks

    OpenAIRE

    SPENZA, DORA

    2013-01-01

    Ubiquitous computing aims at creating smart environments in which computational and communication capabilities permeate the word at all scales, improving the human experience and quality of life in a totally unobtrusive yet completely reliable manner. According to this vision, an huge variety of smart devices and products (e.g., wireless sensor nodes, mobile phones, cameras, sensors, home appliances and industrial machines) are interconnected to realize a network of distributed agents that co...

  10. Structural characterization of O- and C-glycosylating variants of the landomycin glycosyltransferase LanGT2.

    Science.gov (United States)

    Tam, Heng Keat; Härle, Johannes; Gerhardt, Stefan; Rohr, Jürgen; Wang, Guojun; Thorson, Jon S; Bigot, Aurélien; Lutterbeck, Monika; Seiche, Wolfgang; Breit, Bernhard; Bechthold, Andreas; Einsle, Oliver

    2015-02-23

    The structures of the O-glycosyltransferase LanGT2 and the engineered, C-C bond-forming variant LanGT2S8Ac show how the replacement of a single loop can change the functionality of the enzyme. Crystal structures of the enzymes in complex with a nonhydrolyzable nucleotide-sugar analogue revealed that there is a conformational transition to create the binding sites for the aglycon substrate. This induced-fit transition was explored by molecular docking experiments with various aglycon substrates. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    Science.gov (United States)

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

    2016-06-27

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

  12. Wireless sensor platform

    Science.gov (United States)

    Joshi, Pooran C.; Killough, Stephen M.; Kuruganti, Phani Teja

    2017-08-08

    A wireless sensor platform and methods of manufacture are provided. The platform involves providing a plurality of wireless sensors, where each of the sensors is fabricated on flexible substrates using printing techniques and low temperature curing. Each of the sensors can include planar sensor elements and planar antennas defined using the printing and curing. Further, each of the sensors can include a communications system configured to encode the data from the sensors into a spread spectrum code sequence that is transmitted to a central computer(s) for use in monitoring an area associated with the sensors.

  13. Wireless Testbed Bonsai

    Science.gov (United States)

    2006-02-01

    wireless sensor device network, and a about 200 Stargate nodes higher-tier multi-hop peer- to-peer 802.11b wireless network. Leading up to the full ExScal...deployment, we conducted spatial scaling tests on our higher-tier protocols on a 7 × 7 grid of Stargates nodes 45m and with 90m separations respectively...onW and its scaled version W̃ . III. EXPERIMENTAL SETUP Description of Kansei testbed. A stargate is a single board linux-based computer [7]. It uses a

  14. Wireless telecommunication systems

    CERN Document Server

    Terré, Michel; Vivier, Emmanuelle

    2013-01-01

    Wireless telecommunication systems generate a huge amount of interest. In the last two decades, these systems have experienced at least three major technological leaps, and it has become impossible to imagine how society was organized without them. In this book, we propose a macroscopic approach on wireless systems, and aim at answering key questions about power, data rates, multiple access, cellular engineering and access networks architectures.We present a series of solved problems, whose objective is to establish the main elements of a global link budget in several radiocommunicati

  15. Wireless optical telecommunications

    CERN Document Server

    Bouchet, Olivier

    2013-01-01

    Wireless optical communication refers to communication based on the unguided propagation of optical waves. The past 30 years have seen significant improvements in this technique - a wireless communication solution for the current millennium - that offers an alternative to radio systems; a technique that could gain attractiveness due to recent concerns regarding the potential effects of radiofrequency waves on human health.The aim of this book is to look at the free space optics that are already used for the exchange of current information; its many benefits, such as incorporating chan

  16. Sustainable wireless networks

    CERN Document Server

    Zheng, Zhongming; Xuemin

    2013-01-01

    This brief focuses on network planning and resource allocation by jointly considering cost and energy sustainability in wireless networks with sustainable energy. The characteristics of green energy and investigating existing energy-efficient green approaches for wireless networks with sustainable energy is covered in the first part of this brief. The book then addresses the random availability and capacity of the energy supply. The authors explore how to maximize the energy sustainability of the network and minimize the failure probability that the mesh access points (APs) could deplete their

  17. Kimyasal Kabartılan Ürünlerde Kabartma Asitlerinin Fonksiyonel Özellikleri

    Directory of Open Access Journals (Sweden)

    Önder Yıldız

    2015-02-01

    Full Text Available Kimyasal olarak kabartılan ürünlerde kullanılan kabartma tozları sodyum bikarbonat (soda ve bir ya da birden fazla kabartma asidinin birleşmesinden oluşur. Fırın ürünlerinin içyapısına katkıda bulunan koşulları ve reaksiyonları harekete geçiren kabartma asitleri tat, gözenek özelliklerini, kabuk ve iç rengini etkiler. Ayrıca, diğer bileşenler üzerine yaptıkları anyonik ve katyonik etkileşim vasıtasıyla pişmiş ürün kalitesi de değişir. Kalsiyum ve alüminyum iyonlarını içeren kabartma asitleri ince gözenek duvar kalınlığı sağlar ve glüten gelişimine katkıda bulunarak kek tekstürüne esneklik kazandırır. Sonuçta küçük hava kabarcıklarının birleşerek büyük gözenek oluşturma eğilimi azalır. Diğer yandan sülfat ve fosfatları içeren kabartma asitleri glüten gelişimini ve gaz tutulmasını olumsuz etkilerler. Her bir asidin farklı reaksiyon hızı ve CO2 salınım süresine sahip olması son ürün özelliklerine yansır. Son ürünün pH’sı da kek iç rengini etkiler. Düşük pH daha beyaz kek rengi verirken, yüksek pH daha koyu renk verir. Bu çalışmada kimyasal kabartılan ürünlerde kabartma asitlerinin fonksiyonel özellikleri tartışılacaktır.

  18. 75 FR 8400 - In the Matter of Certain Wireless Communications System Server Software, Wireless Handheld...

    Science.gov (United States)

    2010-02-24

    ... Communications System Server Software, Wireless Handheld Devices and Battery Packs; Notice of Investigation... within the United States after importation of certain wireless communications system server software... certain wireless communications system server software, wireless handheld devices or battery packs that...

  19. 75 FR 43206 - In the Matter of Certain Wireless Communications System Server Software, Wireless Handheld...

    Science.gov (United States)

    2010-07-23

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-706] In the Matter of Certain Wireless Communications System Server Software, Wireless Handheld Devices and Battery Packs: Notice of Commission... United States after importation of certain wireless communications system server software, wireless...

  20. Wireless Sensor Network for Indoor Air Quality Monitoring

    Directory of Open Access Journals (Sweden)

    Jun Li

    2014-06-01

    Full Text Available Indoor air quality monitoring system consists of wireless sensor device, nRF24L01 wireless transceiver modules, C8051MCU, STM32103 remote monitoring platform, alarm device and data server. Distributed in the interior space of wireless sensors measure parameters of the local air quality, wireless transceiver module of the MCU to transmit data to the remote monitoring platform for analysis which displayed and stored field environment data or charts. The data collecting from wireless sensors to be send by wireless Access Point to the remote data server based on B/S architecture, intelligent terminals such as mobile phone, laptop, tablet PC on the Internet monitor indoor air quality in real-time. When site environment air quality index data exceeds the threshold in the monitoring device, the remote monitoring platform sends out the alarm SMS signal to inform user by GSM module. Indoor air quality monitoring system uses modular design method, has the portability and scalability has the low manufacture cost, real-time monitoring data and man-machine interaction.

  1. Mechanisms for Prolonging Network Lifetime in Wireless Sensor Networks

    Science.gov (United States)

    Yang, Yinying

    2010-01-01

    Sensors are used to monitor and control the physical environment. A Wireless Sensor Network (WSN) is composed of a large number of sensor nodes that are densely deployed either inside the phenomenon or very close to it [18][5]. Sensor nodes measure various parameters of the environment and transmit data collected to one or more sinks, using…

  2. Environment

    International Nuclear Information System (INIS)

    McIntyre, A.D.; Turnbull, R.G.H.

    1992-01-01

    The development of the hydrocarbon resources of the North Sea has resulted in both offshore and onshore environmental repercussions, involving the existing physical attributes of the sea and seabed, the coastline and adjoining land. The social and economic repercussions of the industry were equally widespread. The dramatic and speedy impact of the exploration and exploitation of the northern North Sea resources in the early 1970s, on the physical resources of Scotland was quickly realised together with the concern that any environmental and social damage to the physical and social fabric should be kept to a minimum. To this end, a wide range of research and other activities by central and local government, and other interested agencies was undertaken to extend existing knowledge on the marine and terrestrial environments that might be affected by the oil and gas industry. The outcome of these activities is summarized in this paper. The topics covered include a survey of the marine ecosystems of the North Sea, the fishing industry, the impact of oil pollution on seabirds and fish stocks, the ecology of the Scottish coastline and the impact of the petroleum industry on a selection of particular sites. (author)

  3. Evaluation of the uncertainty associated with sample holders in NAA measurements in LAN/IPEN

    Energy Technology Data Exchange (ETDEWEB)

    Zahn, Guilherme S.; Ticianelli, Regina B.; Saiki, Mitiko; Genezini, Frederico A., E-mail: ticianelli@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    In IPEN's Neutron Activation Laboratory (LAN/IPEN), thin stainless steel sample holders are used for gamma spectrometry in NAA measurements. This material is very practical, but its chemical composition may be troublesome, as it presents large amounts of elements with intermediate atomic number, with attenuation factors for low-energy gamma-rays that must not be neglected. In this study, count rates obtained using different sample holders were compared. To accomplish that, an Am-241 source, with 59-keV gamma emission, was used so that low-energy gamma attenuation differences can be determined. Moreover, in order to study the energy dependence of these differences, a Ho-166m source was also used. From these results, it was possible to analyze the experimental error associated to the variations between sample holders, with the aim of introducing an addictive term to the uncertainty analysis of comparative Neutron Activation Analysis results. (author)

  4. La fuerza expresiva del deseo en Lan Yu de Stanley Kwan .

    Directory of Open Access Journals (Sweden)

    David L. Eng

    2007-12-01

    Full Text Available Stanley Kwan's Lan Yu configures the emergence of homosexuality in contemporary China far beyond its validation in recognizably Western identitarian terms: the affirmation of an existing but misrecognized minority population; the defense of sexual "perversion"; the positing of sexual freedom, legal recognition, and political rights; the justification of a bourgeois consumer lifestyle, or even the expression of a universalizing and bindingtove bringing togethertwo abstract individuáis. Instead, in Kwan's film, homosexuality and its expressive desire mark the emergence of a new humanism in (postsocialist China under the shadows of global capitalism and neoliberal development. Gays and lesbians, that is, are harbingers of a new modernity, helping to situate China in its proper place within a cosmopolitan globalized world. From this perspective, homosexuality functions as a critical tool for organizing and evaluating the historical continuities and ruptures among China's (semicolonial past, its revolutionary aspirations for a socialist modernity, and its present investments in a neoliberal capitalist world order.

  5. Fitoterapide karminatif olarak kullanılan Apiaceae Meyvaları (Foeniculum vulgare, Pimpinella anisum)

    OpenAIRE

    ORTANCIL, Mahmut

    2006-01-01

    Bu çalışmada halk arasında karminatif olarak kullanılan Apiacea bitkileri Foeniculum vulgareve Pimpinella anisum'un kimyasal özellikleri ve biyolojik etkileri literatür verilerine dayanılarak incelenmiştir.Pimpinella anisum uçucu yağının büyük kısmını anetol oluşturmaktadır. Uçucu yağda ayrıcaöstragol, kumarin yapısında bileşikler (bergapten, umbelliferon ve skopoletol), lipitler(petroselinik asit, palmitik asit, linoleik asit) ve flavonoitler de bulunmaktadır.Pimpinella ...

  6. NuMas: A LAN-based materials control and accounting system in production

    International Nuclear Information System (INIS)

    Strickland, T.W.; Bracey, J.T.; McMahon, S.A.

    1995-01-01

    A state-of-the-art Nuclear Materials Control and Accounting (NMC and A) System has been implemented and is fully operational at the Paducah Gaseous Diffusion Plant (PGDP) as of September 1994. The uranium enrichment facility is currently regulated by the Department of Energy (DOE) and is in the process of obtaining Nuclear Regulatory Commission (NRC) certification. Implementation of this system has resulted in a tremendous cost savings to the facility as well as improvements to the overall efficiency of the NMC and A department. This paper outlines the benefits of implementing a Personal Computer/Local Area Network (PC/LAN)-based system in hopes of attracting other facilities to explore and utilize its application at their sites

  7. ICSW2AN : An Inter-vehicle Communication System Using Mobile Access Point over Wireless Wide Area Networks

    Science.gov (United States)

    Byun, Tae-Young

    This paper presents a prototype of inter-vehicle communication system using mobile access point that internetworks wired or wireless LAN and wireless WAN anywhere. Implemented mobile access point can be equipped with various wireless WAN interfaces such as WCDMA and HSDPA. Mobile access point in the IP mechanism has to process connection setup procedure to one wireless WAN. To show the applicability of the mobile access point to inter-vehicle communication, a simplified V2I2V-based car communication system called ICSW2AN is implemented to evaluate major performance metrics by road test. In addition, results of road test for traffic information service are investigated in view of RTT, latency and server processing time. The experimental result indicates that V2I2V-based car communication system sufficiently can provide time-tolerant traffic information to moving vehicles while more than two mobile devices in restricted spaces such as car, train and ship access wireless Internet simultaneously.

  8. Ninth International Conference on Wireless Communication and Sensor Networks

    CERN Document Server

    Tiwari, Murlidhar; Arora, Anish

    2014-01-01

    Wireless communication and sensor networks would form the backbone to create pervasive and ubiquitous environments that would have profound influence on the society and thus are important to the society. The wireless communication technologies and wireless sensor networks would encompass a wide range of domains such as HW devices such as motes, sensors and associated instrumentation, actuators, transmitters, receivers, antennas, etc., sensor network aspects such as topologies, routing algorithms, integration of heterogeneous network elements and topologies, designing RF devices and systems for energy efficiency and reliability etc. These sensor networks would provide opportunity to continuously and in a distributed manner monitor the environment and generate the necessary warnings and actions. However most of the developments have been demonstrated only in controlled and laboratory environments. So we are yet to see those powerful, ubiquitous applications for the benefit of the society. The conference and con...

  9. Networking wireless sensors

    National Research Council Canada - National Science Library

    Krishnamachari, Bhaskar

    2005-01-01

    ... by networking techniques across multiple layers. The topics covered include network deployment, localization, time synchronization, wireless radio characteristics, medium-access, topology control, routing, data-centric techniques, and transport protocols. Ideal for researchers and designers seeking to create new algorithms and protocols and enginee...

  10. Miniaturized wireless sensor network

    OpenAIRE

    Lecointre , Aubin; Dragomirescu , Daniela; Dubuc , David; Grenier , Katia; Pons , Patrick; Aubert , Hervé; Müller , A.; Berthou , Pascal; Gayraud , Thierry; Plana , Robert

    2006-01-01

    This paper addresses an overview of the wireless sensor networks. It is shown that MEMS/NEMS technologies and SIP concept are well suited for advanced architectures. It is also shown analog architectures have to be compatible with digital signal techniques to develop smart network of microsystem.

  11. Investigating Wireless Power Transfer

    Science.gov (United States)

    St. John, Stuart A.

    2017-01-01

    Understanding Physics is a great end in itself, but is also crucial to keep pace with developments in modern technology. Wireless power transfer, known to many only as a means to charge electric toothbrushes, will soon be commonplace in charging phones, electric cars and implanted medical devices. This article outlines how to produce and use a…

  12. Future of wireless communication

    Energy Technology Data Exchange (ETDEWEB)

    Barker, M

    1996-12-31

    This document reproduces slides from a conference presentation giving an overview of current and upcoming wireless communication methods of interest to Canadian electric utilities. Both voice and data communication methods are considered, including cellular telephone, satellite communications, personal communication services, regulated licensed arrowband data systems, and integrated services.

  13. Wired vs. Wireless.

    Science.gov (United States)

    Fielding, Randall

    2000-01-01

    Presents a debate on which technology will be in tomorrow's classrooms and the pros and cons of wiring classrooms and using a wireless network. Concluding comments address the likelihood, and desirability, of placing computers throughout the entire educational process and what types of computers and capabilities are needed. (GR)

  14. Wireless Remote Control System

    Directory of Open Access Journals (Sweden)

    Adrian Tigauan

    2012-06-01

    Full Text Available This paper presents the design of a wireless remote control system based on the ZigBee communication protocol. Gathering data from sensors or performing control tasks through wireless communication is advantageous in situations in which the use of cables is impractical. An Atmega328 microcontroller (from slave device is used for gathering data from the sensors and transmitting it to a coordinator device with the help of the XBee modules. The ZigBee standard is suitable for low-cost, low-data-rate and low-power wireless networks implementations. The XBee-PRO module, designed to meet ZigBee standards, requires minimal power for reliable data exchange between devices over a distance of up to 1600m outdoors. A key component of the ZigBee protocol is the ability to support networking and this can be used in a wireless remote control system. This system may be employed e.g. to control temperature and humidity (SHT11 sensor and light intensity (TSL230 sensor levels inside a commercial greenhouse.

  15. Insecurity of Wireless Networks

    Energy Technology Data Exchange (ETDEWEB)

    Sheldon, Frederick T [ORNL; Weber, John Mark [Dynetics, Inc.; Yoo, Seong-Moo [University of Alabama, Huntsville; Pan, W. David [University of Alabama, Huntsville

    2012-01-01

    Wireless is a powerful core technology enabling our global digital infrastructure. Wi-Fi networks are susceptible to attacks on Wired Equivalency Privacy, Wi-Fi Protected Access (WPA), and WPA2. These attack signatures can be profiled into a system that defends against such attacks on the basis of their inherent characteristics. Wi-Fi is the standard protocol for wireless networks used extensively in US critical infrastructures. Since the Wired Equivalency Privacy (WEP) security protocol was broken, the Wi-Fi Protected Access (WPA) protocol has been considered the secure alternative compatible with hardware developed for WEP. However, in November 2008, researchers developed an attack on WPA, allowing forgery of Address Resolution Protocol (ARP) packets. Subsequent enhancements have enabled ARP poisoning, cryptosystem denial of service, and man-in-the-middle attacks. Open source systems and methods (OSSM) have long been used to secure networks against such attacks. This article reviews OSSMs and the results of experimental attacks on WPA. These experiments re-created current attacks in a laboratory setting, recording both wired and wireless traffic. The article discusses methods of intrusion detection and prevention in the context of cyber physical protection of critical Internet infrastructure. The basis for this research is a specialized (and undoubtedly incomplete) taxonomy of Wi-Fi attacks and their adaptations to existing countermeasures and protocol revisions. Ultimately, this article aims to provide a clearer picture of how and why wireless protection protocols and encryption must achieve a more scientific basis for detecting and preventing such attacks.

  16. Building the Wireless Campus

    Science.gov (United States)

    Gerraughty, James F.; Shanafelt, Michael E.

    2005-01-01

    This prototype is a continuation of a series of wireless prototypes which began in August 2001 and was reported on again in August 2002. This is the final year of this prototype. This continuation allowed Saint Francis University's Center of Excellence for Remote and Medically Under-Served Areas (CERMUSA) to refine the existing WLAN for the Saint…

  17. Wireless networks; Traadloese nettverk

    Energy Technology Data Exchange (ETDEWEB)

    2008-07-01

    Wireless Local Area Networks - WLAN, is being installed in homes, offices, schools and city areas with an increasing speed. Computers communicate with each other through networks by using radio signals. Base stations make sure there is sufficient radio coverage in the current areas. The effects on human and if it is dangerous is discussed

  18. Wireless networked music performance

    CERN Document Server

    Gabrielli, Leonardo

    2016-01-01

    This book presents a comprehensive overview of the state of the art in Networked Music Performance (NMP) and a historical survey of computer music networking. It introduces current technical trends in NMP and technical issues yet to be addressed. It also lists wireless communication protocols and compares these to the requirements of NMP. Practical use cases and advancements are also discussed.

  19. Radio/antenna mounting system for wireless networking under row-crop agriculture conditions

    Science.gov (United States)

    Interest in and deployment of wireless monitoring systems is increasing in many diverse environments, including row-crop agricultural fields. While many studies have been undertaken to evaluate various aspects of wireless monitoring and networking, such as electronic hardware components, data-colle...

  20. On the Design of a Wireless Multi-antenna Monitoring System

    NARCIS (Netherlands)

    Hofstra, K.L.; Cronie, H.S.

    2004-01-01

    In this paper we investigate the design of a wireless monitoring system. This system consists of several wireless monitoring units, each transmitting data collected from sensors. This data is received and processed at a central control unit. The typical operating environment poses several

  1. Emerging Needs for Pervasive Passive Wireless Sensor Networks on Aerospace Vehicles

    Science.gov (United States)

    Wilson, William C.; Juarez, Peter D.

    2014-01-01

    NASA is investigating passive wireless sensor technology to reduce instrumentation mass and volume in ground testing, air flight, and space exploration applications. Vehicle health monitoring systems (VHMS) are desired on all aerospace programs to ensure the safety of the crew and the vehicles. Pervasive passive wireless sensor networks facilitate VHMS on aerospace vehicles. Future wireless sensor networks on board aerospace vehicles will be heterogeneous and will require active and passive network systems. Since much has been published on active wireless sensor networks, this work will focus on the need for passive wireless sensor networks on aerospace vehicles. Several passive wireless technologies such as microelectromechanical systems MEMS, SAW, backscatter, and chipless RFID techniques, have all shown potential to meet the pervasive sensing needs for aerospace VHMS applications. A SAW VHMS application will be presented. In addition, application areas including ground testing, hypersonic aircraft and spacecraft will be explored along with some of the harsh environments found in aerospace applications.

  2. NASA Bluetooth Wireless Communications

    Science.gov (United States)

    Miller, Robert D.

    2007-01-01

    NASA has been interested in wireless communications for many years, especially when the crew size of the International Space Station (ISS) was reduced to two members. NASA began a study to find ways to improve crew efficiency to make sure the ISS could be maintained with limited crew capacity and still be a valuable research testbed in Low-Earth Orbit (LEO). Currently the ISS audio system requires astronauts to be tethered to the audio system, specifically a device called the Audio Terminal Unit (ATU). Wireless communications would remove the tether and allow astronauts to freely float from experiment to experiment without having to worry about moving and reconnecting the associated cabling or finding the space equivalent of an extension cord. A wireless communication system would also improve safety and reduce system susceptibility to Electromagnetic Interference (EMI). Safety would be improved because a crewmember could quickly escape a fire while maintaining communications with the ground and other crewmembers at any location. In addition, it would allow the crew to overcome the volume limitations of the ISS ATU. This is especially important to the Portable Breathing Apparatus (PBA). The next generation of space vehicles and habitats also demand wireless attention. Orion will carry up to six crewmembers in a relatively small cabin. Yet, wireless could become a driving factor to reduce launch weight and increase habitable volume. Six crewmembers, each tethered to a panel, could result in a wiring mess even in nominal operations. In addition to Orion, research is being conducted to determine if Bluetooth is appropriate for Lunar Habitat applications.

  3. Computerized management of radiology department: Installation and use of local area network(LAN) by personal computers

    International Nuclear Information System (INIS)

    Lee, Young Joon; Han, Kook Sang; Geon, Do Ig; Sol, Chang Hyo; Kim, Byung Soo

    1993-01-01

    There is increasing need for network connecting personal computers(PC) together. Thus local area network(LAN) emerged, which was designed to allow multiple computers to access and share multiple files and programs and expensive peripheral devices and to communicate with each user. We build PC-LAN in our department that consisted of 1) hardware-9 sets of personal computers(IBM compatible 80386 DX, 1 set; 80286 AT, 8 sets) and cables and network interface cards (Ethernet compatible, 16 bits) that connected PC and peripheral devices 2) software - network operating system and database management system. We managed this network for 6 months. The benefits of PC-LAN were 1) multiuser (share multiple files and programs, peripheral devices) 2) real data processing 3) excellent expandability and flexibility, compatibility, easy connectivity 4) single cable for networking) rapid data transmission 5) simple and easy installation and management 6) using conventional PC's software running under DOS(Disk Operating System) without transformation 7) low networking cost. In conclusion, PC-lan provides an easier and more effective way to manage multiuser database system needed at hospital departments instead of more expensive and complex network of minicomputer or mainframe

  4. Realistic Modeling of Wireless Network Environments

    Science.gov (United States)

    2015-03-01

    Simulation, Emulation 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON MICHAEL T...spectrum access. The detailed design and the layout of the SCM and DSP boards was outsourced to outside companies ( DRG Engineering and AmeriCAD...each position. The accuracy of the classification is limited by image quality and the algorithms. However, this general approach has proven to be

  5. Making Wireless Networks Secure for NASA Mission Critical Applications Using Virtual Private Network (VPN) Technology

    Science.gov (United States)

    Nichols, Kelvin F.; Best, Susan; Schneider, Larry

    2004-01-01

    With so many security issues involved with wireless networks, the technology has not been fully utilized in the area of mission critical applications. These applications would include the areas of telemetry, commanding, voice and video. Wireless networking would allow payload operators the mobility to take computers outside of the control room to their off ices and anywhere else in the facility that the wireless network was extended. But the risk is too great of having someone sit just inside of your wireless network coverage and intercept enough of your network traffic to steal proprietary data from a payload experiment or worse yet hack back into your system and do even greater harm by issuing harmful commands. Wired Equivalent Privacy (WEP) is improving but has a ways to go before it can be trusted to protect mission critical data. Today s hackers are becoming more aggressive and innovative, and in order to take advantage of the benefits that wireless networking offer, appropriate security measures need to be in place that will thwart hackers. The Virtual Private Network (VPN) offers a solution to the security problems that have kept wireless networks from being used for mission critical applications. VPN provides a level of encryption that will ensure that data is protected while it is being transmitted over a wireless local area network (LAN). The VPN allows a user to authenticate to the site that the user needs to access. Once this authentication has taken place the network traffic between that site and the user is encapsulated in VPN packets with the Triple Data Encryption Standard (3DES). 3DES is an encryption standard that uses a single secret key to encrypt and decrypt data. The length of the encryption key is 168 bits as opposed to its predecessor DES that has a 56-bit encryption key. Even though 3DES is the common encryption standard for today, the Advance Encryption Standard (AES), which provides even better encryption at a lower cycle cost is growing

  6. A regulations’ survey for the wireless telecommunications deployment in Colombia

    Directory of Open Access Journals (Sweden)

    José Gustavo Morales-Guarín

    2016-01-01

    Full Text Available This paper describes the current wireless telecommunications infrastructure deployment regulations in Colombia. It also refers to the possible effects that this infrastructure could cause to the country`s health and environment. similarly, the results obtained show a comparison between the Argentina’s current regulations, one of the most relevant researches carried out and the Colombian case. finally, some recommendations are proposed that can be considered in the project of regulations applicable in Colombia for the ensuring purpose that the non-ionizing radiation generated by wireless communications systems do not have effects on health and the environment.

  7. Ubiquitous Wireless Smart Sensing and Control

    Science.gov (United States)

    Wagner, Raymond

    2013-01-01

    Need new technologies to reliably and safely have humans interact within sensored environments (integrated user interfaces, physical and cognitive augmentation, training, and human-systems integration tools). Areas of focus include: radio frequency identification (RFID), motion tracking, wireless communication, wearable computing, adaptive training and decision support systems, and tele-operations. The challenge is developing effective, low cost/mass/volume/power integrated monitoring systems to assess and control system, environmental, and operator health; and accurately determining and controlling the physical, chemical, and biological environments of the areas and associated environmental control systems.

  8. Wireless Communications Device Wakeup Method and System

    NARCIS (Netherlands)

    Drago, S.; Sebastiano, F.; Leenaerts, D.M.W.; Breems, L.J.

    2008-01-01

    Abstract of WO 2009044368 Disclosed are wakeable wireless communications devices, and methods for waking wireless communications devices, for use in a wireless network of such devices. The devices communicate during respectively-designated timeslots according to a communications protocol. The

  9. Distortion-Based Slice Level Prioritization for Real-Time Video over QoS-Enabled Wireless Networks

    Directory of Open Access Journals (Sweden)

    Ismail A. Ali

    2012-01-01

    Full Text Available This paper presents a prioritization scheme based on an analysis of the impact on objective video quality when dropping individual slices from coded video streams. It is shown that giving higher-priority classified packets preference in accessing the wireless media results in considerable quality gain (up to 3 dB in tests over the case when no prioritization is applied. The proposed scheme is demonstrated for an IEEE 802.11e quality-of-service- (QoS- enabled wireless LAN. Though more complex prioritization systems are possible, the proposed scheme is crafted for mobile interactive or user-to-user video services and is simply implemented within the Main or the Baseline profiles of an H.264 codec.

  10. Competition in the domain of wireless networks security

    Science.gov (United States)

    Bednarczyk, Mariusz

    2017-04-01

    Wireless networks are very popular and have found wide spread usage amongst various segments, also in military environment. The deployment of wireless infrastructures allow to reduce the time it takes to install and dismantle communications networks. With wireless, users are more mobile and can easily get access to the network resources all the time. However, wireless technologies like WiFi or Bluetooth have security issues that hackers have extensively exploited over the years. In the paper several serious security flaws in wireless technologies are presented. Most of them enable to get access to the internal networks and easily carry out man-in-the-middle attacks. Very often, they are used to launch massive denial of service attacks that target the physical infrastructure as well as the RF spectrum. For instance, there are well known instances of Bluetooth connection spoofing in order to steal WiFi password stored in the mobile device. To raise the security awareness and protect wireless networks against an adversary attack, an analysis of attack methods and tools over time is presented in the article. The particular attention is paid to the severity, possible targets as well as the ability to persist in the context of protective measures. Results show that an adversary can take complete control of the victims' mobile device features if the users forget to use simple safety principles.

  11. The Lure of Wireless Encryption

    CERN Multimedia

    Computer Security Team

    2013-01-01

    Following our article entitled “Jekyll or Hyde? Better browse securely” in the last issue of the Bulletin, some people wondered why the CERN wireless network is not encrypted…   There are many arguments why it is not. The simplest is usability: the communication and management of the corresponding access keys would be challenging given the sheer number of wireless devices the CERN network hosts. Keys would quickly become public, e.g. at conferences, and might be shared, written on whiteboards, etc. Then there are all the devices which cannot be easily configured to use encryption protocols - a fact which would create plenty of calls to the CERN Service Desk… But our main argument is that wireless encryption is DECEPTIVE. Wireless encryption is deceptive as it only protects the wireless network against unauthorised access (and the CERN network already has other means to protect against that). Wireless encryption however, does not really help you. You ...

  12. Matching theory for wireless networks

    CERN Document Server

    Han, Zhu; Saad, Walid

    2017-01-01

    This book provides the fundamental knowledge of the classical matching theory problems. It builds up the bridge between the matching theory and the 5G wireless communication resource allocation problems. The potentials and challenges of implementing the semi-distributive matching theory framework into the wireless resource allocations are analyzed both theoretically and through implementation examples. Academics, researchers, engineers, and so on, who are interested in efficient distributive wireless resource allocation solutions, will find this book to be an exceptional resource. .

  13. Attacks on IEEE 802.11 wireless networks

    Directory of Open Access Journals (Sweden)

    Dejan Milan Tepšić

    2013-06-01

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

  14. Protocol and Topology Issues for Wide-Area Satellite Interconnection of Terrestrial Optical LANs

    Science.gov (United States)

    Parraga, N.

    2002-01-01

    Apart from broadcasting, the satellite business is targeting niche markets. Wide area interconnection is considered as one of these niche markets, since it addresses operators and business LANs (B2B, business to business) in remote areas where terrestrial infrastructure is not available. These LANs - if high-speed - are typically based on optical networks such as SONET. One of the advantages of SONET is its architecture flexibility and capacity to transport all kind of applications including multimedia with a range of different transmission rates. The applications can be carried by different protocols among which the Internet Protocol (IP) or the Asynchronous Transfer Mode (ATM) are the most prominent ones. Thus, the question arises how these protocols can be interconnected via the satellite segment. The paper addresses several solutions for interworking with different protocols. For this investigation we distinguish first of all between the topology and the switching technology of the satellites. In case of a star network with transparent satellite, the satellite protocol consists of physical layer and data layer which can be directly interconnected with layer 2 interworking function to their terrestrial counterparts in the SONET backbone. For regenerative satellites the situation is more complex: here we need to distinguish the types of transport protocols being used in the terrestrial and satellite segment. Whereas IP, ATM, MPEG dominate in the terrestrial networks, satellite systems usually do not follow these standards. Some might employ minor additions (for instance, satellite specific packet headers), some might be completely proprietary. In general, interworking must be done for the data plane on top of layer 2 (data link layer), whereas for the signaling plane the interworking is on top of layer 3. In the paper we will discuss the protocol stacks for ATM, IP, and MPEG with a regenerative satellite system. As an example we will use the EuroSkyWay satellite

  15. An Assessment of Emerging Wireless Broadband Technologies

    National Research Council Canada - National Science Library

    Fountanas, Leonidas

    2001-01-01

    ... technologies in providing broadband services today, emerging wireless broadband technologies are expected to significantly increase their market share over the next years, Deploying a wireless network...

  16. Photonics in wireless transceivers

    International Nuclear Information System (INIS)

    Bogani, A.; Ghelfi, P.

    2013-01-01

    During the last few years, the cross-fertilization between photonics and radio systems has been helping to overcome some major limitations of the classical radio technologies, setting new paradigms, and promising improved performance and new applications with strong benefits for public communications and safety. In particular, photonics-based wireless systems, albeit still at research level, are moving toward a new generation of multifunctional systems able to manage the wireless communication with several different frequencies and protocols, even simultaneously while also realizing surveillance operations. Photonics matches the new requirements of flexibility for software-defined architectures, thanks to its ultra-wide bandwidths and ease of tunability, and guarantees low footprint and weight, thanks to integrated photonic technologies. Moreover, photonics also allows increased resolution and sensitivity by means of the inherent low phase noise of lasers. (author)

  17. Wireless infrared computer control

    Science.gov (United States)

    Chen, George C.; He, Xiaofei

    2004-04-01

    Wireless mouse is not restricted by cable"s length and has advantage over its wired counterpart. However, all the mice available in the market have detection range less than 2 meters and angular coverage less than 180 degrees. Furthermore, commercial infrared mice are based on track ball and rollers to detect movements. This restricts them to be used in those occasions where users want to have dynamic movement, such as presentations and meetings etc. This paper presents our newly developed infrared wireless mouse, which has a detection range of 6 meters and angular coverage of 180 degrees. This new mouse uses buttons instead of traditional track ball and is developed to be a hand-held device like remote controller. It enables users to control cursor with a distance closed to computer and the mouse to be free from computer operation.

  18. Adaptive Wireless Transceiver, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Wireless technologies are an increasingly attractive means for spatial data, input, manipulation, and distribution. Mobitrum is proposing an innovative Adaptive...

  19. Some Challenges in Wireless Security

    National Research Council Canada - National Science Library

    Banerjee, Suman

    2007-01-01

    Wireless communication technologies provide users with significant flexibility and portability and hence is being widely adopted as a preferred mode of communication in many military and civilian applications...

  20. Cognitive wireless networks

    CERN Document Server

    Feng, Zhiyong; Zhang, Ping

    2015-01-01

    This brief examines the current research in cognitive wireless networks (CWNs). Along with a review of challenges in CWNs, this brief presents novel theoretical studies and architecture models for CWNs, advances in the cognitive information awareness and delivery, and intelligent resource management technologies. The brief presents the motivations and concepts of CWNs, including theoretical studies of temporal and geographic distribution entropy as well as cognitive information metrics. A new architecture model of CWNs is proposed with theoretical, functional and deployment architectures suppo

  1. Wearable wireless photoplethysmography sensors

    Science.gov (United States)

    Spigulis, Janis; Erts, Renars; Nikiforovs, Vladimirs; Kviesis-Kipge, Edgars

    2008-04-01

    Wearable health monitoring sensors may support early detection of abnormal conditions and prevention of their consequences. Recent designs of three wireless photoplethysmography monitoring devices embedded in hat, glove and sock, and connected to PC or mobile phone by means of the Bluetooth technology, are described. First results of distant monitoring of heart rate and pulse wave transit time using the newly developed devices are presented.

  2. Wireless Cellular Mobile Communications

    OpenAIRE

    Zalud, V.

    2002-01-01

    In this article is briefly reviewed the history of wireless cellular mobile communications, examined the progress in current second generation (2G) cellular standards and discussed their migration to the third generation (3G). The European 2G cellular standard GSM and its evolution phases GPRS and EDGE are described somewhat in detail. The third generation standard UMTS taking up on GSM/GPRS core network and equipped with a new advanced access network on the basis of code division multiple ac...

  3. Measurements of light at night (LAN) for a sample of female school teachers

    Science.gov (United States)

    Rea, Mark S.; Brons, Jennifer A.; Figueiro, Mariana G.

    2012-01-01

    Epidemiological studies have shown an association between rotating shiftwork and breast cancer (BC) risk. Recently, light at night (LAN) measured by satellite photometry and by self-reports of bedroom brightness has been shown to be associated with BC risk, irrespective of shiftwork history. Importance has been placed on these associations because retinal light exposures at night can suppress the hormone melatonin and/or disrupt circadian entrainment to the local 24-h light-dark cycle. The present study examined whether it was valid to use satellite photometry and self-reports of brightness to characterize light, as it might stimulate the circadian system and thereby affect BC incidence. Calibrated photometric measurements were made at the bedroom windows and in the bedrooms of a sample of female school teachers, who worked regular dayshifts and lived in a variety of satellite-measured sky brightness categories. The light levels at both locations were usually very low and were independent of the amount of satellite-measured light. Calibrated photometric measurements were also obtained at the corneas of these female school teachers together with calibrated accelerometer measurements for seven consecutive days and evenings. Based upon these personal light exposure and activity measurements, the female teachers who participated in this study did not have disrupted light-dark cycles like those associated with rotating shiftworkers who do exhibit a higher risk for BC. Rather, this sample of female school teachers had 24-h light-dark and activity-rest patterns very much like those experienced by dayshift nurses examined in an earlier study who are not at an elevated risk of BC. No relationship was found between the amount of satellite-measured light levels and the 24-h light-dark patterns these women experienced. It was concluded from the present study that satellite photometry is unrelated to personal light exposures as they might affect melatonin suppression and

  4. MASY: Management of secret keys in federated wireless sensor networks

    OpenAIRE

    Maerien, Jef; Michiels, Sam; Huygens, Christophe; Joosen, Wouter

    2010-01-01

    Wireless Sensor Networks are becoming federated and mobile environments. These new capabilities pose a lot of new possibilities and challenges. One of these challenges is to create a secure environment to allow multiple trusted companies to share and merge their sensor network infrastructure. The most basic need for a secure environment is the deployment of key material. However, most current day research assumes pre-shared secrets between the sensor nodes of most, if not all, companies in a ...

  5. Development of wireless intercom for work of excessive noisy places

    International Nuclear Information System (INIS)

    Shiba, Kazuo; Yamashita, Shinichi; Fujita, Tsuneaki; Yamazaki, Katsuyoshi; Sakai, Manabu; Nakanishi, Tomokazu.

    1996-01-01

    Nuclear power stations are often excessively noisy working environments, where conversation and verbal communication are hampered to the extreme. We have developed a small wireless intercom for this and other extremely noisy environments. In the first step of this study, we studied work environment noise and vibration. Results formed the basis of intercom system development. In addition, we have examined the possibilities of optical and microwave intercom systems. (author)

  6. Informatics in Radiology (infoRAD): mobile wireless DICOM server system and PDA with high-resolution display: feasibility of group work for radiologists.

    Science.gov (United States)

    Nakata, Norio; Kandatsu, Susumu; Suzuki, Naoki; Fukuda, Kunihiko

    2005-01-01

    A novel mobile system has been developed for use by radiologists in managing Digital Imaging and Communications in Medicine (DICOM) image data. The system consists of a mobile DICOM server (MDS) and personal digital assistants (PDAs), including a Linux PDA with a video graphics array (VGA) display (307,200 pixels, 3.7 inches). The MDS weighs 410 g, has a 60-GB hard disk drive and a built-in wireless local area network (LAN) access point, and supports a DICOM server (Central Test Node). The Linux-based MDS can be accessed with personal computers (PCs) and PDAs by means of a wireless or wired LAN, and client-server communications can be established at any time. DICOM images can be displayed by using any PDA or PC by means of a Web browser. Simultaneous access to the MDS is possible for multiple authenticated users. With most PDAs, image compression is necessary for complete display of DICOM images; however, the VGA screen can display a 512 x 512-pixel DICOM image almost in its entirety. This wireless system allows efficient management of heavy loads of lossless DICOM image data and will be useful for collaborative work by radiologists in education, conferences, and research.

  7. A Reliable Wireless Control System for Tomato Hydroponics.

    Science.gov (United States)

    Ibayashi, Hirofumi; Kaneda, Yukimasa; Imahara, Jungo; Oishi, Naoki; Kuroda, Masahiro; Mineno, Hiroshi

    2016-05-05

    Agricultural systems using advanced information and communication (ICT) technology can produce high-quality crops in a stable environment while decreasing the need for manual labor. The system collects a wide variety of environmental data and provides the precise cultivation control needed to produce high value-added crops; however, there are the problems of packet transmission errors in wireless sensor networks or system failure due to having the equipment in a hot and humid environment. In this paper, we propose a reliable wireless control system for hydroponic tomato cultivation using the 400 MHz wireless band and the IEEE 802.15.6 standard. The 400 MHz band, which is lower than the 2.4 GHz band, has good obstacle diffraction, and zero-data-loss communication is realized using the guaranteed time-slot method supported by the IEEE 802.15.6 standard. In addition, this system has fault tolerance and a self-healing function to recover from faults such as packet transmission failures due to deterioration of the wireless communication quality. In our basic experiments, the 400 MHz band wireless communication was not affected by the plants' growth, and the packet error rate was less than that of the 2.4 GHz band. In summary, we achieved a real-time hydroponic liquid supply control with no data loss by applying a 400 MHz band WSN to hydroponic tomato cultivation.

  8. A Reliable Wireless Control System for Tomato Hydroponics

    Science.gov (United States)

    Ibayashi, Hirofumi; Kaneda, Yukimasa; Imahara, Jungo; Oishi, Naoki; Kuroda, Masahiro; Mineno, Hiroshi

    2016-01-01

    Agricultural systems using advanced information and communication (ICT) technology can produce high-quality crops in a stable environment while decreasing the need for manual labor. The system collects a wide variety of environmental data and provides the precise cultivation control needed to produce high value-added crops; however, there are the problems of packet transmission errors in wireless sensor networks or system failure due to having the equipment in a hot and humid environment. In this paper, we propose a reliable wireless control system for hydroponic tomato cultivation using the 400 MHz wireless band and the IEEE 802.15.6 standard. The 400 MHz band, which is lower than the 2.4 GHz band, has good obstacle diffraction, and zero-data-loss communication is realized using the guaranteed time-slot method supported by the IEEE 802.15.6 standard. In addition, this system has fault tolerance and a self-healing function to recover from faults such as packet transmission failures due to deterioration of the wireless communication quality. In our basic experiments, the 400 MHz band wireless communication was not affected by the plants’ growth, and the packet error rate was less than that of the 2.4 GHz band. In summary, we achieved a real-time hydroponic liquid supply control with no data loss by applying a 400 MHz band WSN to hydroponic tomato cultivation. PMID:27164105

  9. 3D-Printed Disposable Wireless Sensors with Integrated Microelectronics for Large Area Environmental Monitoring

    KAUST Repository

    Farooqui, Muhammad Fahad; Karimi, Muhammad Akram; Salama, Khaled N.; Shamim, Atif

    2017-01-01

    disposable, compact, dispersible 3D-printed wireless sensor nodes with integrated microelectronics which can be dispersed in the environment and work in conjunction with few fixed nodes for large area monitoring applications. As a proof of concept

  10. Analisi terminologica dei siti web delle Compagnie Aeree British Airways, Alitalia, Tam e LAN

    Directory of Open Access Journals (Sweden)

    Claudia Maria Astorino

    2012-02-01

    Full Text Available This study is part of a research about the terminology found in the language of tourism, defined as an area of ??knowledge. It has been conducted a study based upon the terms used by four major international airlines - two from Europe: British Airways (United Kingdom and Alitalia (Italy, and two from Latin America: TAM (Brazil and Lan (Chile - in their websites, designed for the final consumer (passenger, since each of them has a different official language (English, Italian, Portuguese and Spanish, respectively. The specific objectives were: i to reflect about the differences among the terms used by each airline, ii to analyze whether there is a substantial presence of acronyms, iii to identify how each of these airlines use English, considering that only the first one has it as its official language. The hypothesis that have guided the research are: i there are no significant changes among the terminology used by the airlines which are the object of the present research, ii, there is a fair use of synonyms for the same concepts, iii there is an extensive use of acronyms, iv there is a considerable influence of English, that may be seen in language borrowings and in some hybrid formations.

  11. The extrinsic cell death pathway and the élan mortel.

    Science.gov (United States)

    Wallach, D; Kang, T-B; Kovalenko, A

    2008-10-01

    Early in the exploration of the chemical nature of life, it was widely believed that the molecules of living organisms, by their very nature, differ from those of inorganic material molecules and possess a vital force ('élan vital'). Similarly, early scientific thinking on the subject of cell death and its induction by cytotoxic cells of the immune system was pervaded by a sense that the molecules mediating these functions possess intrinsic deadly activity and are dedicated exclusively to death-related tasks. This impression was also reflected in the initial notions of the mode of action of intracellular proteins that signal for death. It is now gradually becoming clear, however, that proteins participating in death induction also have functions unrelated to death. Nevertheless, as exemplified by studies of the function of caspase-8 (an enzyme that signals both for activation of the extrinsic cell-death pathway and for non-death-related effects), analysis of the mechanistic basis for such heterogeneity might allow identification of distinct structural determinants in the proteins participating in death induction that do bear death specificity.

  12. Adaptive Indoor Positioning Model Based on WLAN-Fingerprinting for Dynamic and Multi-Floor Environments

    Directory of Open Access Journals (Sweden)

    Iyad Husni Alshami

    2017-08-01

    Full Text Available The Global Positioning System demonstrates the significance of Location Based Services but it cannot be used indoors due to the lack of line of sight between satellites and receivers. Indoor Positioning Systems are needed to provide indoor Location Based Services. Wireless LAN fingerprints are one of the best choices for Indoor Positioning Systems because of their low cost, and high accuracy, however they have many drawbacks: creating radio maps is time consuming, the radio maps will become outdated with any environmental change, different mobile devices read the received signal strength (RSS differently, and peoples’ presence in LOS between access points and mobile device affects the RSS. This research proposes a new Adaptive Indoor Positioning System model (called DIPS based on: a dynamic radio map generator, RSS certainty technique and peoples’ presence effect integration for dynamic and multi-floor environments. Dynamic in our context refers to the effects of people and device heterogeneity. DIPS can achieve 98% and 92% positioning accuracy for floor and room positioning, and it achieves 1.2 m for point positioning error. RSS certainty enhanced the positioning accuracy for floor and room for different mobile devices by 11% and 9%. Then by considering the peoples’ presence effect, the error is reduced by 0.2 m. In comparison with other works, DIPS achieves better positioning without extra devices.

  13. Priority image transmission in wireless sensor networks

    International Nuclear Information System (INIS)

    Nasri, M.; Helali, A.; Sghaier, H.; Maaref, H.

    2011-01-01

    The emerging technology during the last years allowed the development of new sensors equipped with wireless communication which can be organized into a cooperative autonomous network. Some application areas for wireless sensor networks (WSNs) are home automations, health care services, military domain, and environment monitoring. The required constraints are limited capacity of processing, limited storage capability, and especially these nodes are limited in energy. In addition, such networks are tiny battery powered which their lifetime is very limited. During image processing and transmission to the destination, the lifetime of sensor network is decreased quickly due to battery and processing power constraints. Therefore, digital image transmissions are a significant challenge for image sensor based Wireless Sensor Networks (WSNs). Based on a wavelet image compression, we propose a novel, robust and energy-efficient scheme, called Priority Image Transmission (PIT) in WSN by providing various priority levels during image transmissions. Different priorities in the compressed image are considered. The information for the significant wavelet coeffcients are transmitted with higher quality assurance, whereas relatively less important coefficients are transmitted with lower overhead. Simulation results show that the proposed scheme prolongs the system lifetime and achieves higher energy efficiency in WSN with an acceptable compromise on the image quality.

  14. Optical wireless communication in data centers

    Science.gov (United States)

    Arnon, Shlomi

    2018-01-01

    In the last decade data centers have become a crucial element in modern human society. However, to keep pace with internet data rate growth, new technologies supporting data center should develop. Integration of optical wireless communication (OWC) in data centers is one of the proposed technologies as augmented technology to the fiber network. One implementation of the OWC technology is deployment of optical wireless transceiver on top of the existing cable/fiber network as extension to the top of rack (TOR) switch; in this way, a dynamic and flexible network is created. Optical wireless communication could reduce energy consumption, increase the data rate, reduce the communication latency, increase flexibility and scalability, and reduce maintenance time and cost, in comparison to extra fiber network deployment. In this paper we review up to date literature in the field, propose an implementation scheme of OWC network, discuss ways to reduce energy consumption by parallel link communication and report preliminary measurement result of university data center environment.

  15. A mobile field-work data collection system for the wireless era of health surveillance.

    Science.gov (United States)

    Forsell, Marianne; Sjögren, Petteri; Renard, Matthew; Johansson, Olle

    2011-03-01

    In many countries or regions the capacity of health care resources is below the needs of the population and new approaches for health surveillance are needed. Innovative projects, utilizing wireless communication technology, contribute to reliable methods for field-work data collection and reporting to databases. The objective was to describe a new version of a wireless IT-support system for field-work data collection and administration. The system requirements were drawn from the design objective and translated to system functions. The system architecture was based on fieldwork experiences and administrative requirements. The Smartphone devices were HTC Touch Diamond2s, while the system was based on a platform with Microsoft .NET components, and a SQL Server 2005 with Microsoft Windows Server 2003 operating system. The user interfaces were based on .NET programming, and Microsoft Windows Mobile operating system. A synchronization module enabled download of field data to the database, via a General Packet Radio Services (GPRS) to a Local Area Network (LAN) interface. The field-workers considered the here-described applications user-friendly and almost self-instructing. The office administrators considered that the back-office interface facilitated retrieval of health reports and invoice distribution. The current IT-support system facilitates short lead times from fieldwork data registration to analysis, and is suitable for various applications. The advantages of wireless technology, and paper-free data administration need to be increasingly emphasized in development programs, in order to facilitate reliable and transparent use of limited resources.

  16. Entre games e folgações: apontamentos de uma antropóloga na lan house Between games and folgações: Anthropological notes in the lan house

    Directory of Open Access Journals (Sweden)

    Vanessa Andrade Pereira

    2007-11-01

    Full Text Available O objetivo deste artigo é apresentar o processo de aproximação da pesquisadora junto a jovens de uma lan house da cidade de Porto Alegre, RS, Brasil. Visa descrever as características dessa casa de jogo em rede, sua localização no bairro, e o cotidiano dos jovens que a usam para jogar games pela Internet ou apenas como point de sociabilidade. Demonstra como os jovens configuram seus pertencimentos e intensificam seus laços sociais através das "folgações" (jocosidade, e das interações online no game Tibia.This article wants to describe the interaction process of the anthropologist with teenagers in a lan house in Porto Alegre, Rio Grande do Sul, Brazil. First, the study will point out the peculiarities of the lan house, its location in the neighbourhood, as well as the everyday life of the young people who use this space for online playing or just for sociability. Secondly, it will discuss as youth people establish their sense of belonging and strengthen their social bounds through the folgações (joking relationships and their online interactions in the MMORPG Tibia game.

  17. Channel Bonding in Linux Ethernet Environment using Regular Switching Hub

    Directory of Open Access Journals (Sweden)

    Chih-wen Hsueh

    2004-06-01

    Full Text Available Bandwidth plays an important role for quality of service in most network systems. There are many technologies developed to increase host bandwidth in a LAN environment. Most of them need special hardware support, such as switching hub that supports IEEE Link Aggregation standard. In this paper, we propose a Linux solution to increase the bandwidth between hosts with multiple network adapters connected to a regular switching hub. The approach is implemented as two Linux kernel modules in a LAN environment without modification to the hardware and operating systems on host machines. Packets are dispatched to bonding network adapters for transmission. The proposed approach is backward compatible, flexible and transparent to users and only one IP address is needed for multiple bonding network adapters. Evaluation experiments in TCP and UDP transmission are shown with bandwidth gain proportionally to the number of network adapters. It is suitable for large-scale LAN systems with high bandwidth requirement, such as clustering systems.

  18. Green Wireless Power Transfer Networks

    NARCIS (Netherlands)

    Liu, Q.; Golinnski, M.; Pawelczak, P.; Warnier, M.

    2016-01-01

    wireless power transfer network (WPTN) aims to support devices with cable-less energy on-demand. Unfortunately, wireless power transfer itself-especially through radio frequency radiation rectification-is fairly inefficient due to decaying power with distance, antenna polarization, etc.

  19. Smart Home Wireless Sensor Nodes

    DEFF Research Database (Denmark)

    Lynggaard, Per

    . This paper introduces an approach that considerably lowers the wireless sensor node power consumption and the amount of transmitted sensor events. It uses smart objects that include artificial intelligence to efficiently process the sensor event on location and thereby saves the costly wireless...

  20. Next Generation Intelligent Wireless Infrastructure

    DEFF Research Database (Denmark)

    Toftegaard, Thomas Skjødeberg

    2010-01-01

    Given the commercial success of wireless technologies that has already taken place over the last couple of decades, with a global mobile communication penetration beyond 3 billion subscribers as well as the enormous success of wireless data communication through IEEE 802.11x and Bluetooth, people...

  1. An Analysis Of Wireless Security

    OpenAIRE

    Salendra Prasad

    2017-01-01

    The WLAN security includes Wired Equivalent Primary WEP and WI-FI protected Access WPA. Today WEP is regarded as very poor security standard. WEP was regarded as very old security standard and has many security issues which users need to be addressed. In this Paper we will discuss Wireless Security and ways to improve on wireless security.

  2. Will available bit rate (ABR) services give us the capability to offer virtual LANs over wide-area ATM networks?

    Science.gov (United States)

    Ferrandiz, Ana; Scallan, Gavin

    1995-10-01

    The available bit rate (ABR) service allows connections to exceed their negotiated data rates during the life of the connections when excess capacity is available in the network. These connections are subject to flow control from the network in the event of network congestion. The ability to dynamically adjust the data rate of the connection can provide improved utilization of the network and be a valuable service to end users. ABR type service is therefore appropriate for the transmission of bursty LAN traffic over a wide area network in a manner that is more efficient and cost effective than allocating bandwdith at the peak cell rate. This paper describes the ABR service and discusses if it is realistic to operate a LAN like service over a wide area using ABR.

  3. Wireless Sensor Network Handles Image Data

    Science.gov (United States)

    2008-01-01

    To relay data from remote locations for NASA s Earth sciences research, Goddard Space Flight Center contributed to the development of "microservers" (wireless sensor network nodes), which are now used commercially as a quick and affordable means to capture and distribute geographical information, including rich sets of aerial and street-level imagery. NASA began this work out of a necessity for real-time recovery of remote sensor data. These microservers work much like a wireless office network, relaying information between devices. The key difference, however, is that instead of linking workstations within one office, the interconnected microservers operate miles away from one another. This attribute traces back to the technology s original use: The microservers were originally designed for seismology on remote glaciers and ice streams in Alaska, Greenland, and Antarctica-acquiring, storing, and relaying data wirelessly between ground sensors. The microservers boast three key attributes. First, a researcher in the field can establish a "managed network" of microservers and rapidly see the data streams (recovered wirelessly) on a field computer. This rapid feedback permits the researcher to reconfigure the network for different purposes over the course of a field campaign. Second, through careful power management, the microservers can dwell unsupervised in the field for up to 2 years, collecting tremendous amounts of data at a research location. The third attribute is the exciting potential to deploy a microserver network that works in synchrony with robotic explorers (e.g., providing ground truth validation for satellites, supporting rovers as they traverse the local environment). Managed networks of remote microservers that relay data unsupervised for up to 2 years can drastically reduce the costs of field instrumentation and data rec

  4. Multi-Channel Wireless Sensor Networks: Protocols, Design and Evaluation

    NARCIS (Netherlands)

    Durmaz, O.

    2009-01-01

    Pervasive systems, which are described as networked embedded systems integrated with everyday environments, are considered to have the potential to change our daily lives by creating smart surroundings and by their ubiquity, just as the Internet. In the last decade, “Wireless Sensor Networks��? have

  5. Less is more : data reduction in wireless sensor networks

    NARCIS (Netherlands)

    Masoum, Alireza

    2018-01-01

    Wireless sensor networks are monitoring systems consisting of many small, low-cost and low-power devices called sensor nodes. A large number of sensor nodes are deployed in an environment to monitor a physical phenomenon, execute light processes on collected data, and send either raw data or

  6. Data retrieval time for energy harvesting wireless sensors

    NARCIS (Netherlands)

    Mitici, M.A.; Goseling, Jasper; de Graaf, Maurits; Boucherie, Richardus J.

    2015-01-01

    We consider the problem of retrieving a reliable estimate of an attribute monitored by a wireless sensor network, where the sensors harvest energy from the environment independently, at random. Each sensor stores the harvested energy in batteries of limited capacity. Moreover, provided they have

  7. Performance analysis of data retrieval in wireless sensor networks

    NARCIS (Netherlands)

    Mitici, M.A.

    2015-01-01

    Wireless sensor networks are currently revolutionizing the way we live, work, and interact with the surrounding environment. Due to their ease of deployment, cost effectiveness and versatile functionality, sensors are employed in a wide range of areas such as environmental monitoring, surveillance

  8. Unlocking the Laboratory: Autonomous Wireless Sensor Authentication in Practice

    Science.gov (United States)

    Huggard, Meriel; McGoldrick, Ciaran

    2013-01-01

    Purpose: The purpose of this study is to evaluate a practical laboratory task where final year undergraduate students design, implement and validate an inferred security wireless sensor access system. Design/methodology/approach: The quality of the learning and technical environment was evaluated from a number of perspectives using a mixed methods…

  9. Distributed Service Discovery for Heterogeneous Wireless Sensor Networks

    NARCIS (Netherlands)

    Marin Perianu, Raluca; Scholten, Johan; Havinga, Paul J.M.

    Service discovery in heterogeneous Wireless Sensor Networks is a challenging research objective, due to the inherent limitations of sensor nodes and their extensive and dense deployment. The protocols proposed for ad hoc networks are too heavy for sensor environments. This paper presents a

  10. A forensic readiness model for Wireless Local Area Networks

    CSIR Research Space (South Africa)

    Ngobeni, S

    2010-01-01

    Full Text Available of cyber crime, where criminals deliberately and actively break into WLANs with the intent to cause harm or access sensitive information. WLAN digital forensics is seen not only as a response to cyber crime in wireless environments, but also as a means...

  11. Energy efficiency of error correction on wireless systems

    NARCIS (Netherlands)

    Havinga, Paul J.M.

    1999-01-01

    Since high error rates are inevitable to the wireless environment, energy-efficient error-control is an important issue for mobile computing systems. We have studied the energy efficiency of two different error correction mechanisms and have measured the efficiency of an implementation in software.

  12. Prototyping Service Discovery and Usage in Wireless Sensor Networks

    NARCIS (Netherlands)

    Marin Perianu, Raluca; Scholten, Johan; Havinga, Paul J.M.

    2007-01-01

    Heterogeneous Wireless Sensor Networks (WSNs) are envisioned to provide different types of services in an open and dynamic environment. This paper presents the design, implementation and evaluation of a service discovery and usage solution for heterogeneous WSNs. The users have the possibility to

  13. Seamless integrated network system for wireless communication systems

    NARCIS (Netherlands)

    Wu, Gang; Mizuno, Mitsuhiko; Hase, Yoshihiro; Havinga, Paul J.M.

    2006-01-01

    To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly

  14. Seamless integrated network system for wireless communication systems

    NARCIS (Netherlands)

    Wu, Gang; Mizuno, Mitsuhiko; Hase, Yoshihiro; Havinga, Paul J.M.

    2002-01-01

    To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly

  15. Adaptive Multipath Key Reinforcement for Energy Harvesting Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Di Mauro, Alessio; Dragoni, Nicola

    2015-01-01

    Energy Harvesting - Wireless Sensor Networks (EH-WSNs) constitute systems of networked sensing nodes that are capable of extracting energy from the environment and that use the harvested energy to operate in a sustainable state. Sustainability, seen as design goal, has a significant impact...

  16. El Lanús : Memoria, política y psicoanálisis en la Argentina (1956-1992)

    NARCIS (Netherlands)

    Visacovsky, S.E.

    2001-01-01

    En este trabajo son estudiados los procesos de construcción de la memoria social en la Argentina, y las relaciones entre memorias políticas y memorias profesionales. El objeto empírico son los relatos sobre el pasado del más célebre servicio de salud mental de la Argentina, conocido como el Lanús

  17. Spent Mushroom Waste as a Media Replacement for Peat Moss in Kai-Lan (Brassica oleracea var. Alboglabra Production

    Directory of Open Access Journals (Sweden)

    H. Sendi

    2013-01-01

    Full Text Available Peat moss (PM is the most widely used growing substrate for the pot culture. Due to diminishing availability and increasing price of PM, researchers are looking for viable alternatives for peat as a growth media component for potted plants. A pot study was conducted with a view to investigate the possibility of using spent mushroom waste (SMW for Kai-lan (Brassica oleracea var. Alboglabra production replacing peat moss (PM in growth media. The treatments evaluated were 100% PM (control, 100% SMW, and mixtures of SMW and PM in different ratios like 1 : 1, 1 : 2, and 2 : 1 (v/v with/without NPK amendment. The experiment was arranged in a completely randomized design with five replications per treatment. Chemical properties like pH and salinity level (EC of SMW were within the acceptable range of crop production but, nutrient content, especially nitrogen content was not enough to provide sufficient nutrition to plant for normal growth. Only PM (100% and SMW and PM mixture in 1 : 1 ratio with NPK amendment performed equally in terms of Kai-lan growth. This study confirms the feasibility of replacing PM by SMW up to a maximum of 50% in the growth media and suggests that NPK supplementation from inorganic sources is to ensure a higher productivity of Kai-lan.

  18. Wireless Technology in K-12 Education

    Science.gov (United States)

    Walery, Darrell

    2004-01-01

    Many schools begin implementing wireless technology slowly by creating wireless "hotspots" on the fly. This is accomplished by putting a wireless access point on a cart along with a set of wireless laptop computers. A teacher can then wheel the cart anywhere in the school that has a network drop, plug the access point in and have an…

  19. Effects of wireless packet loss in industrial process control systems.

    Science.gov (United States)

    Liu, Yongkang; Candell, Richard; Moayeri, Nader

    2017-05-01

    Timely and reliable sensing and actuation control are essential in networked control. This depends on not only the precision/quality of the sensors and actuators used but also on how well the communications links between the field instruments and the controller have been designed. Wireless networking offers simple deployment, reconfigurability, scalability, and reduced operational expenditure, and is easier to upgrade than wired solutions. However, the adoption of wireless networking has been slow in industrial process control due to the stochastic and less than 100% reliable nature of wireless communications and lack of a model to evaluate the effects of such communications imperfections on the overall control performance. In this paper, we study how control performance is affected by wireless link quality, which in turn is adversely affected by severe propagation loss in harsh industrial environments, co-channel interference, and unintended interference from other devices. We select the Tennessee Eastman Challenge Model (TE) for our study. A decentralized process control system, first proposed by N. Ricker, is adopted that employs 41 sensors and 12 actuators to manage the production process in the TE plant. We consider the scenario where wireless links are used to periodically transmit essential sensor measurement data, such as pressure, temperature and chemical composition to the controller as well as control commands to manipulate the actuators according to predetermined setpoints. We consider two models for packet loss in the wireless links, namely, an independent and identically distributed (IID) packet loss model and the two-state Gilbert-Elliot (GE) channel model. While the former is a random loss model, the latter can model bursty losses. With each channel model, the performance of the simulated decentralized controller using wireless links is compared with the one using wired links providing instant and 100% reliable communications. The sensitivity of the

  20. Wireless Distributed Antenna MIMO

    DEFF Research Database (Denmark)

    2015-01-01

    The present disclosure relates to system applications of multicore optical fibers. One embodiment relates to a base transceiver station for a wireless telecommunication system comprising a plurality of antenna units arranged in a MIMO configuration and adapted for transmission and/or reception...... of radio-frequency signals, an optical transmitter in the form of an electro-optic conversion unit for each of said plurality of antenna units, each electro-optic conversion unit adapted for converting an RF signal into an optical signal, a plurality of a single core optical fibers for guiding the optical...

  1. Dynamic wireless sensor networks

    CERN Document Server

    Oteafy, Sharief M A

    2014-01-01

    In this title, the authors leap into a novel paradigm of scalability and cost-effectiveness, on the basis of resource reuse. In a world with much abundance of wirelessly accessible devices, WSN deployments should capitalize on the resources already available in the region of deployment, and only augment it with the components required to meet new application requirements. However, if the required resources already exist in that region, WSN deployment converges to an assignment and scheduling scheme to accommodate for the new application given the existing resources. Such resources are polled

  2. Investigating wireless power transfer

    Science.gov (United States)

    St John, Stuart A.

    2017-09-01

    Understanding Physics is a great end in itself, but is also crucial to keep pace with developments in modern technology. Wireless power transfer, known to many only as a means to charge electric toothbrushes, will soon be commonplace in charging phones, electric cars and implanted medical devices. This article outlines how to produce and use a simple set of equipment to both demonstrate and investigate this phenomenon. It presents some initial findings and aims to encourage Physics educators and their students to conduct further research, pushing the bounds of their understanding.

  3. Deployable wireless Fresnel lens

    Science.gov (United States)

    Kennedy, Timothy F. (Inventor); Fink, Patrick W. (Inventor); Chu, Andrew W. (Inventor); Lin, Gregory Y. (Inventor)

    2013-01-01

    Apparatus and methods for enhancing the gain of a wireless signal are provided. In at least one specific embodiment, the apparatus can include a screen comprised of one or more electrically conductive regions for reflecting electromagnetic radiation and one or more non-conductive regions for permitting electromagnetic radiation therethrough. The one or more electrically conductive regions can be disposed adjacent to at least one of the one or more non-conductive regions. The apparatus can also include a support member disposed about at least a portion of the screen. The screen can be capable of collapsing by twisting the support member in opposite screw senses to form interleaved concentric sections.

  4. Wireless Headset Communication System

    Science.gov (United States)

    Lau, Wilfred K.; Swanson, Richard; Christensen, Kurt K.

    1995-01-01

    System combines features of pagers, walkie-talkies, and cordless telephones. Wireless headset communication system uses digital modulation on spread spectrum to avoid interference among units. Consists of base station, 4 radio/antenna modules, and as many as 16 remote units with headsets. Base station serves as network controller, audio-mixing network, and interface to such outside services as computers, telephone networks, and other base stations. Developed for use at Kennedy Space Center, system also useful in industrial maintenance, emergency operations, construction, and airport operations. Also, digital capabilities exploited; by adding bar-code readers for use in taking inventories.

  5. Wired or Wireless Internet?

    DEFF Research Database (Denmark)

    Gimpel, Gregory

    2010-01-01

    This paper finds that network externalities play a minimal role in the choice of internet access technology. Potential adopters of mobile laptop internet view broadband technology as a black box, the technological details of which donot matter. The study uses qualitative techniques to explore how...... the speed of technological obsolescence, market share dominance, and the black boxing of technology influence consumer intention to adopt WiMax and 3G wireless internet for their laptop computers. The results, implications for industry, and areas for further research are discussed....

  6. Wireless passive radiation sensor

    Science.gov (United States)

    Pfeifer, Kent B; Rumpf, Arthur N; Yelton, William G; Limmer, Steven J

    2013-12-03

    A novel measurement technique is employed using surface acoustic wave (SAW) devices, passive RF, and radiation-sensitive films to provide a wireless passive radiation sensor that requires no batteries, outside wiring, or regular maintenance. The sensor is small (<1 cm.sup.2), physically robust, and will operate unattended for decades. In addition, the sensor can be insensitive to measurement position and read distance due to a novel self-referencing technique eliminating the need to measure absolute responses that are dependent on RF transmitter location and power.

  7. Wireless installation standard

    International Nuclear Information System (INIS)

    Lim, Hwang Bin

    2007-12-01

    This is divided six parts which are radio regulation law on securing of radio resource, use of radio resource, protection of radio resource, radio regulation enforcement ordinance with securing, distribution and assignment of radio regulation, radio regulation enforcement regulation on utility of radio resource and technical qualification examination, a wireless installation regulation of technique standard and safety facility standard, radio regulation such as certification regulation of information communicative machines and regulation of radio station on compliance of signal security, radio equipment in radio station, standard frequency station and emergency communication.

  8. Wireless Cellular Mobile Communications

    Directory of Open Access Journals (Sweden)

    V. Zalud

    2002-12-01

    Full Text Available In this article is briefly reviewed the history of wireless cellularmobile communications, examined the progress in current secondgeneration (2G cellular standards and discussed their migration to thethird generation (3G. The European 2G cellular standard GSM and itsevolution phases GPRS and EDGE are described somewhat in detail. Thethird generation standard UMTS taking up on GSM/GPRS core network andequipped with a new advanced access network on the basis of codedivision multiple access (CDMA is investigated too. A sketch of theperspective of mobile communication beyond 3G concludes this article.

  9. Wireless sensor networks architectures and protocols

    CERN Document Server

    Callaway, Jr, Edgar H

    2003-01-01

    Introduction to Wireless Sensor NetworksApplications and MotivationNetwork Performance ObjectivesContributions of this BookOrganization of this BookThe Development of Wireless Sensor NetworksEarly Wireless NetworksWireless Data NetworksWireless Sensor and Related NetworksConclusionThe Physical LayerSome Physical Layer ExamplesA Practical Physical Layer for Wireless Sensor NetworksSimulations and ResultsConclusionThe Data Link LayerMedium Access Control TechniquesThe Mediation DeviceSystem Analysis and SimulationConclusionThe Network LayerSome Network Design ExamplesA Wireless Sensor Network De

  10. An LDPC decoder architecture for wireless sensor network applications.

    Science.gov (United States)

    Biroli, Andrea Dario Giancarlo; Martina, Maurizio; Masera, Guido

    2012-01-01

    The pervasive use of wireless sensors in a growing spectrum of human activities reinforces the need for devices with low energy dissipation. In this work, coded communication between a couple of wireless sensor devices is considered as a method to reduce the dissipated energy per transmitted bit with respect to uncoded communication. Different Low Density Parity Check (LDPC) codes are considered to this purpose and post layout results are shown for a low-area low-energy decoder, which offers percentage energy savings with respect to the uncoded solution in the range of 40%-80%, depending on considered environment, distance and bit error rate.

  11. An LDPC Decoder Architecture for Wireless Sensor Network Applications

    Science.gov (United States)

    Giancarlo Biroli, Andrea Dario; Martina, Maurizio; Masera, Guido

    2012-01-01

    The pervasive use of wireless sensors in a growing spectrum of human activities reinforces the need for devices with low energy dissipation. In this work, coded communication between a couple of wireless sensor devices is considered as a method to reduce the dissipated energy per transmitted bit with respect to uncoded communication. Different Low Density Parity Check (LDPC) codes are considered to this purpose and post layout results are shown for a low-area low-energy decoder, which offers percentage energy savings with respect to the uncoded solution in the range of 40%–80%, depending on considered environment, distance and bit error rate. PMID:22438724

  12. Virtual View Image over Wireless Visual Sensor Network

    Directory of Open Access Journals (Sweden)

    Gamantyo Hendrantoro

    2011-12-01

    Full Text Available In general, visual sensors are applied to build virtual view images. When number of visual sensors increases then quantity and quality of the information improves. However, the view images generation is a challenging task in Wireless Visual Sensor Network environment due to energy restriction, computation complexity, and bandwidth limitation. Hence this paper presents a new method of virtual view images generation from selected cameras on Wireless Visual Sensor Network. The aim of the paper is to meet bandwidth and energy limitations without reducing information quality. The experiment results showed that this method could minimize number of transmitted imageries with sufficient information.

  13. Research Update: Nanogenerators for self-powered autonomous wireless sensors

    Science.gov (United States)

    Khan, Usman; Hinchet, Ronan; Ryu, Hanjun; Kim, Sang-Woo

    2017-07-01

    Largely distributed networks of sensors based on the small electronics have great potential for health care, safety, and environmental monitoring. However, in order to have a maintenance free and sustainable operation, such wireless sensors have to be self-powered. Among various energies present in our environment, mechanical energy is widespread and can be harvested for powering the sensors. Piezoelectric and triboelectric nanogenerators (NGs) have been recently introduced for mechanical energy harvesting. Here we introduce the architecture and operational modes of self-powered autonomous wireless sensors. Thereafter, we review the piezoelectric and triboelectric NGs focusing on their working mechanism, structures, strategies, and materials.

  14. Slot Antenna for Wireless Temperature Measurement Systems

    DEFF Research Database (Denmark)

    Acar, Öncel; Jakobsen, Kaj Bjarne

    2016-01-01

    This paper presents a novel clover-slot antenna for a surface-acoustic-wave sensor based wireless temperature measurement system. The slot is described by a parametric locus curve that has the shape of a clover. The antenna is operated at high temperatures, in rough environments, and has a 43......% fractional bandwidth at the 2.4 GHz ISM-band. The slot antenna has been optimized for excitation by a passive chip soldered onto it. Measurement results are compared with simulation results and show good agreements....

  15. Cooperative networking in a heterogeneous wireless medium

    CERN Document Server

    Ismail, Muhammad

    2013-01-01

    This brief focuses on radio resource allocation in a heterogeneous wireless medium. It presents radio resource allocation algorithms with decentralized implementation, which support both single-network and multi-homing services. The brief provides a set of cooperative networking algorithms, which rely on the concepts of short-term call traffic load prediction, network cooperation, convex optimization, and decomposition theory. In the proposed solutions, mobile terminals play an active role in the resource allocation operation, instead of their traditional role as passive service recipients in the networking environment.

  16. Coupled geohazards at Southern Andes (Copahue-Lanín volcanoes): Chile's GEO supersite proposal

    Science.gov (United States)

    Lara, Luis E.; Cordova, Loreto

    2017-04-01

    Southern Andes are a young and active mountain belt where volcanism and tectonic processes (and those related to the hydrometeorological conditions controlled by this geological setting) pose a significant threat to the growing communities nearby. This proposal focus on a ca. 200 km long segment of the Southern Andes where 9 stratovolcanoes and 2 distributed volcanic fields are located, just along a tectonic corridor defined by the northern segment of the Liquiñe-Ofqui Faul System (LOFS), a long-lived active strike-slip fault running for 1200 km. Volcanoes in this area take part of the central province of the Andean Southern Volcanic Zone (37-41°S), particularly the northermost portion that is limited at the south by an Andean tranverse fault (Lanalhue Fault, which define the Villarrica-Lanin volcanic chain) and run along the horse-tail array of the LOFS to the north. Most of the stravolcanoes are atop of the LOFS main branch with only 3 exceptions (Callaqui, Tolhuaca and Lanín) 15-20 km away, but related to transverse faults. Hazards in the segment derive from the activity of some of the most active volcanoes in South America (e.g., Villarrica, Llaima), others with long-lasting weak activity (e.g., Copahue) or some volcanoes with low frequency but high magnitude eruptions in the geological record. Only since the beggining of the 20th century 80 eruptions have been recorded in this area. In addition, activity of the LOFS has been detected prior to some eruptions and coeval with some others (e.g., Lonquimay 1989). A strong two-way coupling between tectonics and volcanism has been proposed for the segment but only recently detected by geophysical techniques or numerical modelling. Tectonic triggered landslides are frequent in this region together with debris flows at erupting ice-covered volcanoes or stream headed at high altitude basins. The latter scenario seems to be worst at present because of global climate change. Ground-based monitoring networks for both

  17. Virtual Private Lan Services Over IP/MPLS Networks and Router Configurations

    Directory of Open Access Journals (Sweden)

    Pınar KIRCI

    2015-06-01

    Full Text Available The rising number of users and ever growing traffic rates over the networks reveal the need of higher bandwidth and transmission rates. At every packet transmission process, routers need to route the packets by looking at the routing tables, this fact leads to an increase at the load of the routers and at the amount of time consumed during the processes. Today, users need high level security, faster data transmission and easy managed network structures because of the increasing technology usage. MPLS network structures can provide these requirements with their QoS feature. In our work, at first a topology structure is constructed with the routers that are used in Alcatel-Lucent laboratories. OSPF (Open Shortest Path First routing protocol and MPLS (Multiprotocol Label Switching technologies are used over the topology. Afterwards, E-pipe (Ethernet Pipe and VPLS (Virtual private LAN services configurations are performed over the routers. To illustrate the current network data traffic, three tests are performed in the study. Routers’ configurations are performed by Secure-CRT and still developing i-Gen software. With i-Gen, many routers’ configurations can be performed with a user friendly interface. Instead of performing the configurations one by one with Secure CRT, the user can perform the routers’ configurations easily by entering the needed values for the system with i-Gen software. So, with the new and developing i-Gen software, the users’ workload is minimized and streamlined. In our work, Secure-CRT software which is mostly preferred for router configurations at Windows operating system and i-Gen software which is developed by Alcatel-Lucent are considered. Both of the router configuration softwares are worked on and gained results are expounded. Consequently, instead of using time consuming Secure-CRT software, with utilizing new developed i-Gen software, the users’ work load is minimized.

  18. A study on regulatory guideline for the wireless network design digital I and C system

    International Nuclear Information System (INIS)

    Park, Y. C.; Kang, J. H.; Moon, Y. G.

    2006-06-01

    The paper represents the features of wireless communication in order to adopt to the atomic energy power plant system. The power plant environment of harsh for the robust and reliable wireless data transfer. Before practical installation and usage, it is necessary to evaluate the performance of wireless communication at such a harsh wireless communication environment. In the previous systems, high reliable wired data communication system has been used in common. We have checked the requirements which meet the reliability for that environment and analyzed the basic features of wireless communication. After that, we have a more detail analysis of wireless communication specification, such as IEEE 802 series, IMT-2000, Wibro, so on. Based on the result from analysis, the rules for the reliable system are defined. In the near future, low-power low-cost WSN(Wireless Sensor Network) would be dominant all over the industry. In this paper, the performance and considerations for the power plant is described when adopting to the atomic energy power system. The RF circuit design guide lines are defined, the reliability of the network protocol is defined and and elevated

  19. An Embedded Multi-Agent Systems Based Industrial Wireless Sensor Network.

    Science.gov (United States)

    Taboun, Mohammed S; Brennan, Robert W

    2017-09-14

    With the emergence of cyber-physical systems, there has been a growing interest in network-connected devices. One of the key requirements of a cyber-physical device is the ability to sense its environment. Wireless sensor networks are a widely-accepted solution for this requirement. In this study, an embedded multi-agent systems-managed wireless sensor network is presented. A novel architecture is proposed, along with a novel wireless sensor network architecture. Active and passive wireless sensor node types are defined, along with their communication protocols, and two application-specific examples are presented. A series of three experiments is conducted to evaluate the performance of the agent-embedded wireless sensor network.

  20. The wireless sensor network monitoring system for regional environmental nuclear radiation

    International Nuclear Information System (INIS)

    Liu Chong; Liu Dao; Wang Yaojun; Xie Yuxi; Song Lingling

    2012-01-01

    The wireless sensor network (WSN) technology has been utilized to design a new regional environmental radiation monitoring system based on the wireless sensor networks to meet the special requirements of monitoring the nuclear radiation in certain regions, and realize the wireless transmission of measurement data, information processing and integrated measurement of the nuclear radiation and the corresponding environmental parameters in real time. The system can be applied to the wireless monitoring of nuclear radiation dose in the nuclear radiation environment. The measured data and the distribution of radiation dose can be vividly displayed on the graphical interface in the host computer. The system has functioned with the wireless transmission and control, the data storage, the historical data inquiry, the node remote control. The experimental results show that the system has the advantages of low power consumption, stable performance, network flexibility, range of measurement and so on. (authors)

  1. Adapting cognitive radio technology for low-power wireless personal area network devices

    DEFF Research Database (Denmark)

    Toftegaard, Thomas Skjødeberg; Rohde, John

    2011-01-01

    The application of wireless personal area network (WPAN) and simple point-to-point wireless communication devices has increased drastically both in private household and in our workspaces in general over the last decade. Combined with the fact that the total number of wireless devices...... and associated standards present in the wireless environment is experiencing an extreme growth, the frequency spectrum scarcity is exposed as a severe challenge. Setting up efficient and reliable wireless WPAN links can be challenging even today. This is especially true because of the intensive use...... discusses the challenges associated with the implementation of highly reliable low-power WPAN networks for the future and the adaption of Cognitive Radio technology as a potential solution. A brief status on the maturity of CR technology will be presented as an integral part of this discussion....

  2. An Embedded Multi-Agent Systems Based Industrial Wireless Sensor Network

    Science.gov (United States)

    Brennan, Robert W.

    2017-01-01

    With the emergence of cyber-physical systems, there has been a growing interest in network-connected devices. One of the key requirements of a cyber-physical device is the ability to sense its environment. Wireless sensor networks are a widely-accepted solution for this requirement. In this study, an embedded multi-agent systems-managed wireless sensor network is presented. A novel architecture is proposed, along with a novel wireless sensor network architecture. Active and passive wireless sensor node types are defined, along with their communication protocols, and two application-specific examples are presented. A series of three experiments is conducted to evaluate the performance of the agent-embedded wireless sensor network. PMID:28906452

  3. Register of international standard NP on IT based wireless application in nuclear power plants

    International Nuclear Information System (INIS)

    Koo, I. S.; Hong, S. B.; Cho, I. W.; Choi, Y. S.; Lee, J. C.

    2011-04-01

    DC draft of standard technical report for wireless applications in NPP is developed, which is a Korean IT technologies. Wireless technologies are forwardwd to converging technologies nuclear and IT area. These technologies are supported to reduce vulnerability against cyber attacks and are forwarded to international standards which met with the nuclear environment requirements. DC draft of standard technical report is provided and circulated. Korean experts participate in Plenary meeting for IEC TC45/SC45A and intermediate meeting for IEC SC45A/WGA3 and 9. Korean expert takes the chair of wireless session at ANS winter conference. Visible light communication is experimented for feasibility study on reducing vulnerability against cyber attacks. VLC is capable of robust wireless communication against cyber attacks. This is suggested to describe a method for technical report. Issue DTR for wireless applications in NPP in 2012

  4. Wireless network security theories and applications

    CERN Document Server

    Chen, Lei; Zhang, Zihong

    2013-01-01

    Wireless Network Security Theories and Applications discusses the relevant security technologies, vulnerabilities, and potential threats, and introduces the corresponding security standards and protocols, as well as provides solutions to security concerns. Authors of each chapter in this book, mostly top researchers in relevant research fields in the U.S. and China, presented their research findings and results about the security of the following types of wireless networks: Wireless Cellular Networks, Wireless Local Area Networks (WLANs), Wireless Metropolitan Area Networks (WMANs), Bluetooth

  5. Verification of electromagnetic effects from wireless devices in operating nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Song Hae; Kim, Young Sik; Lyou, Ho Sun; Kim, Min Suk [Korea Hydro and Nuclear Power Co. (KHNP), Central Research Institute, Daejeon (Korea, Republic of); Lyou, Joon [Dept. of Electronics Engineering, Chungnam National University, Daejeon (Korea, Republic of)

    2015-10-15

    Wireless communication technologies, especially smart phones, have become increasingly common. Wireless technology is widely used in general industry and this trend is also expected to grow with the development of wireless technology. However, wireless technology is not currently applied in any domestic operating nuclear power plants (NPPs) because of the highest priority of the safety policy. Wireless technology is required in operating NPPs, however, in order to improve the emergency responses and work efficiency of the operators and maintenance personnel during its operation. The wired telephone network in domestic NPPs can be simply connected to a wireless local area network to use wireless devices. This design change can improve the ability of the operators and personnel to respond to an emergency situation by using important equipment for a safe shutdown. IEEE 802.11 smart phones (Wi-Fi standard), Internet Protocol (IP) phones, personal digital assistant (PDA) for field work, notebooks used with web cameras, and remote site monitoring tablet PCs for on-site testing may be considered as wireless devices that can be used in domestic operating NPPs. Despite its advantages, wireless technology has only been used during the overhaul period in Korean NPPs due to the electromagnetic influence of sensitive equipment and cyber security problems. This paper presents the electromagnetic verification results from major sensitive equipment after using wireless devices in domestic operating NPPs. It also provides a solution for electromagnetic interference/radio frequency interference (EMI/RFI) from portable and fixed wireless devices with a Wi-Fi communication environment within domestic NPPs.

  6. Verification of electromagnetic effects from wireless devices in operating nuclear power plants

    Directory of Open Access Journals (Sweden)

    Song-Hae Ye

    2015-10-01

    Full Text Available Wireless communication technologies, especially smartphones, have become increasingly common. Wireless technology is widely used in general industry and this trend is also expected to grow with the development of wireless technology. However, wireless technology is not currently applied in any domestic operating nuclear power plants (NPPs because of the highest priority of the safety policy. Wireless technology is required in operating NPPs, however, in order to improve the emergency responses and work efficiency of the operators and maintenance personnel during its operation. The wired telephone network in domestic NPPs can be simply connected to a wireless local area network to use wireless devices. This design change can improve the ability of the operators and personnel to respond to an emergency situation by using important equipment for a safe shutdown. IEEE 802.11 smartphones (Wi-Fi standard, Internet Protocol (IP phones, personal digital assistant (PDA for field work, notebooks used with web cameras, and remote site monitoring tablet PCs for on-site testing may be considered as wireless devices that can be used in domestic operating NPPs. Despite its advantages, wireless technology has only been used during the overhaul period in Korean NPPs due to the electromagnetic influence of sensitive equipment and cyber security problems. This paper presents the electromagnetic verification results from major sensitive equipment after using wireless devices in domestic operating NPPs. It also provides a solution for electromagnetic interference/radio frequency interference (EMI/RFI from portable and fixed wireless devices with a Wi-Fi communication environment within domestic NPPs.

  7. Verification of electromagnetic effects from wireless devices in operating nuclear power plants

    International Nuclear Information System (INIS)

    Ye, Song Hae; Kim, Young Sik; Lyou, Ho Sun; Kim, Min Suk; Lyou, Joon

    2015-01-01

    Wireless communication technologies, especially smart phones, have become increasingly common. Wireless technology is widely used in general industry and this trend is also expected to grow with the development of wireless technology. However, wireless technology is not currently applied in any domestic operating nuclear power plants (NPPs) because of the highest priority of the safety policy. Wireless technology is required in operating NPPs, however, in order to improve the emergency responses and work efficiency of the operators and maintenance personnel during its operation. The wired telephone network in domestic NPPs can be simply connected to a wireless local area network to use wireless devices. This design change can improve the ability of the operators and personnel to respond to an emergency situation by using important equipment for a safe shutdown. IEEE 802.11 smart phones (Wi-Fi standard), Internet Protocol (IP) phones, personal digital assistant (PDA) for field work, notebooks used with web cameras, and remote site monitoring tablet PCs for on-site testing may be considered as wireless devices that can be used in domestic operating NPPs. Despite its advantages, wireless technology has only been used during the overhaul period in Korean NPPs due to the electromagnetic influence of sensitive equipment and cyber security problems. This paper presents the electromagnetic verification results from major sensitive equipment after using wireless devices in domestic operating NPPs. It also provides a solution for electromagnetic interference/radio frequency interference (EMI/RFI) from portable and fixed wireless devices with a Wi-Fi communication environment within domestic NPPs

  8. A Wireless Implantable Switched-Capacitor Based Optogenetic Stimulating System

    Science.gov (United States)

    Lee, Hyung-Min; Kwon, Ki-Yong; Li, Wen

    2015-01-01

    This paper presents a power-efficient implantable optogenetic interface using a wireless switched-capacitor based stimulating (SCS) system. The SCS efficiently charges storage capacitors directly from an inductive link and periodically discharges them into an array of micro-LEDs, providing high instantaneous power without affecting wireless link and system supply voltage. A custom-designed computer interface in LabVIEW environment wirelessly controls stimulation parameters through the inductive link, and an optrode array enables simultaneous neural recording along with optical stimulation. The 4-channel SCS system prototype has been implemented in a 0.35-μm CMOS process and combined with the optrode array. In vivo experiments involving light-induced local field potentials verified the efficacy of the SCS system. An implantable version of the SCS system with flexible hermetic sealing is under development for chronic experiments. PMID:25570099

  9. A solar charge and discharge controller for wireless sensor nodes

    Science.gov (United States)

    Dang, Yibo; Shen, Shu

    2018-02-01

    Aiming at the energy supply problem that restricts the life of wireless sensor nodes, a solar energy charge and discharge controller suitable for wireless sensor nodes is designed in this paper. A Microcontroller is used as the core of the solar charge and discharge controller. The software of the solar charge and discharge controller adopts the C language to realize the program of the main control module. Firstly, the function of monitoring solar panel voltage and lithium battery voltage are simulated by Protel software, and the charge time is tested in cloudy and overcast outdoor environment. The results of the experiment show that our controller meets the power supply demand of wireless sensor nodes.

  10. A Survey on Secure Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Shihong Zou

    2017-01-01

    Full Text Available Combining tiny sensors and wireless communication technology, wireless body area network (WBAN is one of the most promising fields. Wearable and implantable sensors are utilized for collecting the physiological data to achieve continuously monitoring of people’s physical conditions. However, due to the openness of wireless environment and the significance and privacy of people’s physiological data, WBAN is vulnerable to various attacks; thus, strict security mechanisms are required to enable a secure WBAN. In this article, we mainly focus on a survey on the security issues in WBAN, including securing internal communication in WBAN and securing communication between WBAN and external users. For each part, we discuss and identify the security goals to be achieved. Meanwhile, relevant security solutions in existing research on WBAN are presented and their applicability is analyzed.

  11. Biomonitoring with Wireless Communications

    Energy Technology Data Exchange (ETDEWEB)

    Budinger, Thomas F.

    2003-03-01

    This review is divided into three sections: technologies for monitoring physiological parameters; biosensors for chemical assays and wireless communications technologies including image transmissions. Applications range from monitoring high risk patients for heart, respiratory activity and falls to sensing levels of physical activity in military, rescue, and sports personnel. The range of measurements include, heart rate, pulse wave form, respiratory rate, blood oxygen, tissue pCO2, exhaled carbon dioxide and physical activity. Other feasible measurements will employ miniature chemical laboratories on silicon or plastic chips. The measurements can be extended to clinical chemical assays ranging from common blood assays to protein or specialized protein measurements (e.g., troponin, creatine, and cytokines such as TNF and IL6). Though the feasibility of using wireless technology to communicate vital signs has been demonstrated 32 years ago (1) it has been only recently that practical and portable devices and communications net works have become generally available for inexpensive deployment of comfortable and affordable devices and systems.

  12. Household wireless electroencephalogram hat

    Science.gov (United States)

    Szu, Harold; Hsu, Charles; Moon, Gyu; Yamakawa, Takeshi; Tran, Binh

    2012-06-01

    We applied Compressive Sensing to design an affordable, convenient Brain Machine Interface (BMI) measuring the high spatial density, and real-time process of Electroencephalogram (EEG) brainwaves by a Smartphone. It is useful for therapeutic and mental health monitoring, learning disability biofeedback, handicap interfaces, and war gaming. Its spec is adequate for a biomedical laboratory, without the cables hanging over the head and tethered to a fixed computer terminal. Our improved the intrinsic signal to noise ratio (SNR) by using the non-uniform placement of the measuring electrodes to create the proximity of measurement to the source effect. We computing a spatiotemporal average the larger magnitude of EEG data centers in 0.3 second taking on tethered laboratory data, using fuzzy logic, and computing the inside brainwave sources, by Independent Component Analysis (ICA). Consequently, we can overlay them together by non-uniform electrode distribution enhancing the signal noise ratio and therefore the degree of sparseness by threshold. We overcame the conflicting requirements between a high spatial electrode density and precise temporal resolution (beyond Event Related Potential (ERP) P300 brainwave at 0.3 sec), and Smartphone wireless bottleneck of spatiotemporal throughput rate. Our main contribution in this paper is the quality and the speed of iterative compressed image recovery algorithm based on a Block Sparse Code (Baranuick et al, IEEE/IT 2008). As a result, we achieved real-time wireless dynamic measurement of EEG brainwaves, matching well with traditionally tethered high density EEG.

  13. Ultra low power signal oriented approach for wireless health monitoring.

    Science.gov (United States)

    Marinkovic, Stevan; Popovici, Emanuel

    2012-01-01

    In recent years there is growing pressure on the medical sector to reduce costs while maintaining or even improving the quality of care. A potential solution to this problem is real time and/or remote patient monitoring by using mobile devices. To achieve this, medical sensors with wireless communication, computational and energy harvesting capabilities are networked on, or in, the human body forming what is commonly called a Wireless Body Area Network (WBAN). We present the implementation of a novel Wake Up Receiver (WUR) in the context of standardised wireless protocols, in a signal-oriented WBAN environment and present a novel protocol intended for wireless health monitoring (WhMAC). WhMAC is a TDMA-based protocol with very low power consumption. It utilises WBAN-specific features and a novel ultra low power wake up receiver technology, to achieve flexible and at the same time very low power wireless data transfer of physiological signals. As the main application is in the medical domain, or personal health monitoring, the protocol caters for different types of medical sensors. We define four sensor modes, in which the sensors can transmit data, depending on the sensor type and emergency level. A full power dissipation model is provided for the protocol, with individual hardware and application parameters. Finally, an example application shows the reduction in the power consumption for different data monitoring scenarios.

  14. Wireless sensor network performance metrics for building applications

    Energy Technology Data Exchange (ETDEWEB)

    Jang, W.S. (Department of Civil Engineering Yeungnam University 214-1 Dae-Dong, Gyeongsan-Si Gyeongsangbuk-Do 712-749 South Korea); Healy, W.M. [Building and Fire Research Laboratory, 100 Bureau Drive, Gaithersburg, MD 20899-8632 (United States)

    2010-06-15

    Metrics are investigated to help assess the performance of wireless sensors in buildings. Wireless sensor networks present tremendous opportunities for energy savings and improvement in occupant comfort in buildings by making data about conditions and equipment more readily available. A key barrier to their adoption, however, is the uncertainty among users regarding the reliability of the wireless links through building construction. Tests were carried out that examined three performance metrics as a function of transmitter-receiver separation distance, transmitter power level, and obstruction type. These tests demonstrated, via the packet delivery rate, a clear transition from reliable to unreliable communications at different separation distances. While the packet delivery rate is difficult to measure in actual applications, the received signal strength indication correlated well with the drop in packet delivery rate in the relatively noise-free environment used in these tests. The concept of an equivalent distance was introduced to translate the range of reliability in open field operation to that seen in a typical building, thereby providing wireless system designers a rough estimate of the necessary spacing between sensor nodes in building applications. It is anticipated that the availability of straightforward metrics on the range of wireless sensors in buildings will enable more widespread sensing in buildings for improved control and fault detection. (author)

  15. ``Low Power Wireless Technologies: An Approach to Medical Applications''

    Science.gov (United States)

    Bellido O., Francisco J.; González R., Miguel; Moreno M., Antonio; de La Cruz F, José Luis

    Wireless communication supposed a great both -quantitative and qualitative, jump in the management of the information, allowing the access and interchange of it without the need of a physical cable connection. The wireless transmission of voice and information has remained in constant evolution, arising new standards like BluetoothTM, WibreeTM or ZigbeeTM developed under the IEEE 802.15 norm. These newest wireless technologies are oriented to systems of communication of short-medium distance and optimized for a low cost and minor consume, becoming recognized as a flexible and reliable medium for data communications across a broad range of applications due to the potential that the wireless networks presents to operate in demanding environments providing clear advantages in cost, size, power, flexibility, and distributed intelligence. About the medical applications, the remote health or telecare (also called eHealth) is getting a bigger place into the manufacturers and medical companies, in order to incorporate products for assisted living and remote monitoring of health parameteres. At this point, the IEEE 1073, Personal Health Devices Working Group, stablish the framework for these kind of applications. Particularly, the 1073.3.X describes the physical and transport layers, where the new ultra low power short range wireless technologies can play a big role, providing solutions that allow the design of products which are particularly appropriate for monitor people’s health with interoperability requirements.

  16. Wireless local area network for the dental office.

    Science.gov (United States)

    Mupparapu, Muralidhar

    2004-01-01

    Dental offices are no exception to the implementation of new and advanced technology, especially if it enhances productivity. In a rapidly transforming digital world, wireless technology has a special place, as it has truly "retired the wire" and contributed to the ease and efficient access to patient data and other software-based applications for diagnosis and treatment. If the office or the clinic is networked, access to patient management software, imaging software and treatment planning tools is enhanced. Access will be further enhanced and unrestricted if the entire network is wireless. As with any new, emerging technology, there will be issues that should be kept in mind before adapting to the wireless environment. Foremost is the network security involved in the installation and use of these wireless networks. This short, technical manuscript deals with standards and choices in wireless technology currently available for implementation within a dental office. The benefits of each network security protocol available to protect patient data and boost the efficiency of a modern dental office are discussed.

  17. Indirubin, a component of Ban-Lan-Gen, activates CYP3A4 gene transcription through the human pregnane X receptor.

    Science.gov (United States)

    Kumagai, Takeshi; Aratsu, Yusuke; Sugawara, Ryosuke; Sasaki, Takamitsu; Miyairi, Shinichi; Nagata, Kiyoshi

    2016-04-01

    Ban-Lan-Gen is the common name for the dried roots of indigo plants, including Polygonum tinctorium, Isatis indigotica, Isatis tinctoria, and Strobilanthes cusia. Ban-Lan-Gen is frequently used as an anti-inflammatory and an anti-viral for the treatment of hepatitis, influenza, and various types of inflammation. One of the cytochrome P450 (CYP) enzymes, CYP3A4, is responsible for the metabolism of a wide variety of xenobiotics, including an estimated 60% of all clinically used drugs. In this study, we investigated the effect of Ban-Lan-Gen on the transcriptional activation of the CYP3A4 gene. Ban-Lan-Gen extract increased CYP3A4 gene reporter activity in a dose-dependent manner. Indirubin, one of the biologically active ingredients in the Ban-Lan-Gen, also dose-dependently increased CYP3A4 gene reporter activity. Expression of short hairpin RNA for the human pregnane X receptor (hPXR-shRNA) inhibited CYP3A4 gene reporter activity, and overexpression of human PXR increased indirubin- and rifampicin-induced CYP3A4 gene reporter activity. Furthermore, indirubin induced CYP3A4 mRNA expression in HepG2 cells. Taken together, these results indicate that indirubin, a component of Ban-Lan-Gen, activated CYP3A4 gene transcription through the activation of the human PXR. Copyright © 2016. Published by Elsevier Ltd.

  18. Dimensioning Method for Conversational Video Applications in Wireless Convergent Networks

    Directory of Open Access Journals (Sweden)

    Raquel Perez Leal

    2007-12-01

    Full Text Available New convergent services are becoming possible, thanks to the expansion of IP networks based on the availability of innovative advanced coding formats such as H.264, which reduce network bandwidth requirements providing good video quality, and the rapid growth in the supply of dual-mode WiFi cellular terminals. This paper provides, first, a comprehensive subject overview as several technologies are involved, such as medium access protocol in IEEE802.11, H.264 advanced video coding standards, and conversational application characterization and recommendations. Second, the paper presents a new and simple dimensioning model of conversational video over wireless LAN. WLAN is addressed under the optimal network throughput and the perspective of video quality. The maximum number of simultaneous users resulting from throughput is limited by the collisions taking place in the shared medium with the statistical contention protocol. The video quality is conditioned by the packet loss in the contention protocol. Both approaches are analyzed within the scope of the advanced video codecs used in conversational video over IP, to conclude that conversational video dimensioning based on network throughput is not enough to ensure a satisfactory user experience, and video quality has to be taken also into account. Finally, the proposed model has been applied to a real-office scenario.

  19. Dimensioning Method for Conversational Video Applications in Wireless Convergent Networks

    Directory of Open Access Journals (Sweden)

    Alonso JoséI

    2008-01-01

    Full Text Available Abstract New convergent services are becoming possible, thanks to the expansion of IP networks based on the availability of innovative advanced coding formats such as H.264, which reduce network bandwidth requirements providing good video quality, and the rapid growth in the supply of dual-mode WiFi cellular terminals. This paper provides, first, a comprehensive subject overview as several technologies are involved, such as medium access protocol in IEEE802.11, H.264 advanced video coding standards, and conversational application characterization and recommendations. Second, the paper presents a new and simple dimensioning model of conversational video over wireless LAN. WLAN is addressed under the optimal network throughput and the perspective of video quality. The maximum number of simultaneous users resulting from throughput is limited by the collisions taking place in the shared medium with the statistical contention protocol. The video quality is conditioned by the packet loss in the contention protocol. Both approaches are analyzed within the scope of the advanced video codecs used in conversational video over IP, to conclude that conversational video dimensioning based on network throughput is not enough to ensure a satisfactory user experience, and video quality has to be taken also into account. Finally, the proposed model has been applied to a real-office scenario.

  20. Microwave materials for wireless applications

    CERN Document Server

    Cruickshank, David B

    2011-01-01

    This practical resource offers you an in-depth, up-to-date understanding of the use of microwave magnetic materials for cutting-edge wireless applications. The book discusses device applications used in wireless infrastructure base stations, point-to-point radio links, and a range of more specialized microwave systems. You find detailed discussions on the attributes of each family of magnetic materials with respect to specific wireless applications. Moreover, the book addresses two of the hottest topics in the field today - insertion loss and intermodulation. This comprehensive reference also