• Title/Summary/Keyword: Selection efficiency

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Improved Compressed Network Coding Scheme for Energy-Efficient Data Communication in Wireless Sensor Networks

  • Zhou, Ying;Yang, Lihua;Yang, Longxiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.6
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    • pp.2946-2962
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    • 2017
  • An improved energy-efficient compressed network coding method is proposed for the data communication in the wireless sensor networks (WSNs). In the method, the compressed sensing and network coding are jointly used to improve the energy efficiency, and the two-hop neighbor information is employed to choose the next hop to further reduce the number of the transmissions. Moreover, a new packet format is designed to facilitate the intermediate node selection. To theoretically verify the efficiency of the proposed method, the expressions for the number of the transmissions and receptions are derived. Simulation results show that, the proposed method has higher energy efficiency compared with the available schemes, and it only requires a few packets to reconstruct measurements with reasonable quality.

A Study on Generator Temperature and Power Converter Efficiency according to change of Wind Velocity (풍속 변화에 따른 발전기 온도 및 전력변환장치 효율에 관한 연구)

  • Song, Young-Sang;Han, Woon-Ki;Jung, Jin-Soo;Lim, Hyun-Sung;Cho, Sung-Koo;Jeon, Taehyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.29 no.7
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    • pp.8-13
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    • 2015
  • Recently, because a renewable power source must operate as a constant rate in accordance with RPS(Renewable Portfolio Standard), the study of the renewable power sources has been ongoing. Especially because of noise of wind turbine, troubleshooting, and urban greening business, research related with small wind turbine are underway. The economics and reliability are important parts for the activation of small wind turbine, such as solar energy. In this paper, by analyzing the temperature variations for each location and efficiency of power conversion devices in accordance with short period wind speed changes in simulation test, we reviewed the safety about temperature variations of wind generator and the method of selection of power converter.

Visualization of Acupoint by Image Overlapping of Skin Current (피부전류량의 화상중첩에 의한 경혈의 시각화)

  • 이용흠;김용진;고수복;정동명
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.563-566
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    • 1999
  • The functional diagnosis instrument should be preceded first to both the accurate selection of exact acupoint and discrimination. so the measuring and stimulating method are improved to SPAC pattern to evaluate impedance existed in the body. As a result, the resistance factor between skin and probe, the dipolization of cell was reduced so that the judgement of acupoint is advanced. After extraction of optimization parameter of SPAC pattern which the high discrimination efficiency and the lowest affection on the human body is controlled by using microprocessor to enhance conviction. The discrimination efficiency was confirmed by meridian visualization system. Also mechanism of probe was improved to increase efficiency of image recognition processing. The image of discriminated acupoint with probe is obtained by using a camera, the location on the tip of probe is recognized and processed. And then these are converted to virtual color by proportional to measuring current level of scan point on skin.

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The Contribution of Molecular Physiology to the Improvement of Nitrogen Use Efficiency in Crops

  • Hirel, Bertrand;Chardon, Fabien;Durand, Jacques
    • Journal of Crop Science and Biotechnology
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    • v.10 no.3
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    • pp.123-132
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    • 2007
  • In this review, we discuss the ways in which our understanding of the controls of nitrogen use efficiency applied to crop improvement has been increased through the development of molecular physiology studies using transgenic plants or mutants with modified capacities for nitrogen uptake, assimilation and recycling. More recently, exploiting crop genetic variability through quantitative trait loci and candidate gene detection has opened new perspectives toward the identification of key structural or regulatory elements involved in the control of nitrogen metabolism for improving crop productivity. All together these studies strongly suggest that in the near future nitrogen use efficiency can be improved both by marker-assisted selection and genetic engineering, thus having the most promise for the practical application of increasing the capacity of a wide range of economically important species to take up and utilize nitrogen more efficiently.

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Power Closed-loop Control of Switched Reluctance Generator for High Efficiency Operation

  • Li, Zhenguo;Gao, Dongdong;Ahn, Jin-Woo
    • Journal of international Conference on Electrical Machines and Systems
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    • v.1 no.3
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    • pp.397-403
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    • 2012
  • This paper describes a control method of turn-on/off angles to improve the efficiency of the switched reluctance generator(SRG) with a power closed-loop control system, and the inner-loop of the system is current hysteresis control. The SRG control system is constituted by the PI power controller and the two-level current hysteresis controller. By measuring and analyzing the system losses of different reference powers, speeds and turn-on/off angles, selection strategy of optimal turn-on/off angles is discussed. The proposed method is simple, reliable, and easy to achieve.

Adaptive Decode-and-Forward Cooperative Networks with Multiple Relay Nodes

  • Vu, Ha Nguyen;Kong, Hyung-Yun
    • Journal of electromagnetic engineering and science
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    • v.11 no.1
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    • pp.5-10
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    • 2011
  • We propose an adaptive cooperative scheme with a multi-relay node that achieves high bandwidth efficiency and achieves better SEP performance. In the proposed protocol, if the quality of the direct channel is better than that of the all channels from relays to destination, the source will transmit directly to the destination. Otherwise, the source broadcasts the signal and then a potential relay will be chosen to help the source. A re-transmission will also occur if the potential relay cannot be detected. The spectral efficiency is first derived by calculating the probability of each mode, i.e., direct and cooperation transmission. Subsequently, the SEP performance of M-PSK modulation for the scheme is analyzed by considering each event where the source transmits data to the destination. Finally, the obtained analytical results are verified through computer simulations.

A Study on Fast Maximum Efficiency Control of Stator-Flux-oriented Induction Motor Drives

  • Shin, Myoung-Ho
    • Journal of Electrical Engineering and Technology
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    • v.6 no.5
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    • pp.626-633
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    • 2011
  • This paper presents a novel maximum efficiency control scheme for convergence improvement in stator-flux-oriented induction motor drives. Three input powers are calculated at three different flux levels, respectively. A quadratic curve is obtained using the quadratic interpolation method using the three points. The flux level at the lowest point of the interpolated curve is calculated, which is not the real minimum input power of the motor, but an estimated one. Hence, the quadratic interpolations are repeated with three new points chosen using the selection method for new points for refitting until the convergence criteria are satisfied. The proposed method is verified by simulation results.

Design of the Fuzzy-based Mobile Model for Energy Efficiency within a Wireless Sensor Network

  • Yun, Dai Yeol;Lee, Daesung
    • Journal of information and communication convergence engineering
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    • v.19 no.3
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    • pp.136-141
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    • 2021
  • Research on wireless sensor networks has focused on the monitoring and characterization of large-scale physical environments and the tracking of various environmental or physical conditions, such as temperature, pressure, and wind speed. We propose a stochastic mobility model that can be applied to a MANET (Mobile Ad-hoc NETwork). environment, and apply this mobility model to a newly proposed clustering-based routing protocol. To verify its stability and durability, we compared the proposed stochastic mobility model with a random model in terms of energy efficiency. The FND (First Node Dead) was measured and compared to verify the performance of the newly designed protocol. In this paper, we describe the proposed mobility model, quantify the changes to the mobile environment, and detail the selection of cluster heads and clusters formed using a fuzzy inference system. After the clusters are configured, the collected data are sent to a base station. Studies on clustering-based routing protocols and stochastic mobility models for MANET applications have shown that these strategies improve the energy efficiency of a network.

A Synchronization Scheme Based on Moving Average for Robust Audio Watermarking

  • Zhang, Jinquan;Han, Bin
    • Journal of Information Processing Systems
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    • v.15 no.2
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    • pp.271-287
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    • 2019
  • The synchronization scheme based on moving average is robust and suitable for the same rule to be adopted in embedding watermark and synchronization code, but the imperceptibility and search efficiency is seldom reported. The study aims to improve the original scheme for robust audio watermarking. Firstly, the survival of the algorithm from desynchronization attacks is improved. Secondly, the scheme is improved in inaudibility. Objective difference grade (ODG) of the marked audio is significantly changed. Thirdly, the imperceptibility of the scheme is analyzed and the derived result is close to experimental result. Fourthly, the selection of parameters is optimized based on experimental data. Fifthly, the search efficiency of the scheme is compared with those of other synchronization code schemes. The experimental results show that the proposed watermarking scheme allows the high audio quality and is robust to common attacks such as additive white Gaussian noise, requantization, resampling, low-pass filtering, random cropping, MP3 compression, jitter attack, and time scale modification. Moreover, the algorithm has the high search efficiency and low false alarm rate.

EERA: ENHANCED EFFICIENT ROUTING ALGORITHM FOR MOBILE SENSOR NETWORK

  • Hemalatha, S;Raj, E.George Dharma Prakash
    • International Journal of Computer Science & Network Security
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    • v.22 no.9
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    • pp.389-395
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    • 2022
  • A Mobile Sensor Network is widely used in real time applications. A critical need in Mobile Sensor Network is to achieve energy efficiency during routing as the sensor nodes have scarce energy resource. The nodes' mobility in MWSN poses a challenge to design an energy efficient routing protocol. Clustering helps to achieve energy efficiency by reducing the organization complexity overhead of the network which is proportional to the number of nodes in the network. This paper proposes"EERA: Energy Efficient Routing Algorithm for Mobile Sensor Network" is divided into five phases. 1, Cluster Formation 2.Cluster head and Transmission head selection 3.Path Establishment / Route discovery and 4,Data Transmission. Experimental Analysis has been done and is found that the proposed method performs better than the existing method with respect to four parameters.