• Title/Summary/Keyword: Sensing

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Social Incentives for Cooperative Spectrum Sensing in Distributed Cognitive Radio Networks

  • Feng, Jingyu;Lu, Guangyue;Min, Xiangcen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.2
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    • pp.355-370
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    • 2014
  • Cooperative spectrum sensing has been considered as a promising approach to improve the sensing performance in distributed cognitive radio networks. However, there may exist some selfish secondary users (SUs) who are unwilling to cooperate. The presence of selfish SUs could cause catastrophic damage to the performance of cooperative spectrum sensing. Following the social perspective, we propose a Social Tie-based Incentive Scheme (STIS) to deal with the selfish problem for cooperative spectrum sensing in distributed cognitive radio networks. This scheme inspires SUs to contribute sensing information for the SUs who have social tie but not others, and such willingness varies with the strength of social tie value. The evaluation of each SU's social tie derives from its contribution for others. Finally, simulation results validate the effectiveness of the proposed scheme.

The Development of a National-scale Land use /Land cover Change Detection System in Taiwan

  • Chen, Chi-Farn;Wang, Ann-Chiang;Chang, Li-Yu;chang, Ching-Yueh;Lee, Pei-Shan;cheng, Chao-Yao
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.567-569
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    • 2003
  • Because of the limited land resources, an efficient land use management to reach the sustainable development policy has become an urgent call in Taiwan. A long-term project entitled 'National land use monitoring program-the establishment of a land use change detection system' has been jointly conducted by both National Central University and Ministry of Interior since year of 2001. The main aim of the project is to use the remote sensing images to detect the land use changes on a national scale. This plan has been put into practice and indeed provides an effective assistance for land management.

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Acyl-Homoserine lactone Quorum Sensing in Bactreria

  • Greenberg, E.Peter
    • Journal of Microbiology
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    • v.38 no.3
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    • pp.117-121
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    • 2000
  • Recent advances in studies of bacterial gene expression and light microscopy show that cell-to cell communication and communication and community behavior are the rule rather than the exception. One type of cell-cell communication, quorum sensing in Gram-negative bacteria involves acyl-homoserine lactone signals. This type of quorum sension represents a dedicated communication system that enables a given species to sense when it has reached a critical population density. and to respond by activating expression of specific genes. The LuxR and LuxI proteins of Vibrio fisheri are the founding members of the acyl-homoserine lactone quorum sensing signal receptor and signal generator families of proteins. Acyl-homeserine lactone signaling in Pseudomonas aeruginosa is one model for the relationship between quorum sensing community behavior, and virulence. In the P. aeruginosa model. quorum sensing is required for normal biofilm maturation and virulence. There are multiple quorum-sensing circuits that control the expression of dozens of specific genes in P. aeruginosa.

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Nanopatterning using Machining Force Sensing Module (미세 가공력 검출기구를 이용한 나노패터닝)

  • 방진혁;권기환;박재준;조남규
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.1109-1112
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    • 2004
  • This paper presents a high sensitive force sensing module to measure machining forces for a tip-based nanopatterning instrument. The force sensing module utilizing a leaf spring mechanism and a capacitive displacement sensor has been designed to provide a measuring range from 80$\mu$N to 8N. This force sensing module is mounted on a PZT driven in-feed motion stage with 1 nm resolution. The sample can be moved by a X-Y scanning motion stage with 5 nm resolution. In the patterning experiments, the machining forces were controlled and monitored by the force sensing module. Then, the patterned sample was measured by AFM. Experimental results demonstrated that the developed force sensing module can be used as an effective sensing device in the nanopatterning operation.

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Self-sensing measurement of piezo inkjet and its Applications (피에조 잉크젯의 셀프 센싱 검출 및 응용)

  • Kwon, Kye-Si;Kim, Wou-Sik;Kim, Sang-Il;Shin, Seung-Joo;Kim, Seong-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.366-372
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    • 2007
  • Self-sensing measurement of piezo inkjet and its application are discussed. The pressure wave inside the inkjet dispenser was measured by current measurement due to self-sensing capability of PZT. The pressure wave measured from current was verified by commercially available laser vibrometer. Here, two applications using self-sensing signal were discussed: waveform design for high speed jetting and condition monitoring. For waveform design, two pulse waveform was designed based on self-sensing signal such that the pressure wave after droplet formation can be minimized. For condition monitoring, self-sensing signal was shown to be effective in detecting air bubble trapped in inkjet printhead.

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Characterization and modeling of a self-sensing MR damper under harmonic loading

  • Chen, Z.H.;Ni, Y.Q.;Or, S.W.
    • Smart Structures and Systems
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    • v.15 no.4
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    • pp.1103-1120
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    • 2015
  • A self-sensing magnetorheological (MR) damper with embedded piezoelectric force sensor has recently been devised to facilitate real-time close-looped control of structural vibration in a simple and reliable manner. The development and characterization of the self-sensing MR damper are presented based on experimental work, which demonstrates its reliable force sensing and controllable damping capabilities. With the use of experimental data acquired under harmonic loading, a nonparametric dynamic model is formulated to portray the nonlinear behaviors of the self-sensing MR damper based on NARX modeling and neural network techniques. The Bayesian regularization is adopted in the network training procedure to eschew overfitting problem and enhance generalization. Verification results indicate that the developed NARX network model accurately describes the forward dynamics of the self-sensing MR damper and has superior prediction performance and generalization capability over a Bouc-Wen parametric model.

THE PAN OCEAN REMOTE SENSING CONFERENCE ASSOCIATION --- OUR GREETING TO THE FULL CONFERENCE ISRS2006PORSEC

  • Katsaros, Kristina B.
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.3-6
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    • 2006
  • This presentation delivers the Appreciation of the The Pan Ocean Remote Sensing Conference Association for the cooperation with the Korean Society of Remote Sensing in organizing a joint conference with the International Symposium of Remote Sensing. It includes a brief history of the PORSEC Association with its mission and aims and the system of governance of the organization. Our vision for the future, is presented from this president's point of view. It includes a discussion of building expert capacity to use remote sensing techniques in developing nations by the sharing of knowledge and our ability to promote predictability of natural hazards with our workshops and science sessions. The article ends with an appreciation of our many sponsors.

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Estimation of the Sensing Ability According to Smart Sensor Types (지적센서의 형태에 따른 센싱능력 평가)

  • 황성연;홍동표;강희용
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.10 no.4
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    • pp.111-117
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    • 2001
  • In this paper, we will propose the new method that estimates the sensing ability of smart sensor. A study is estimation method that evaluates the sensing ability about smart sensor respectively. According to acceleration(g) and displacement changing, we estimated the sensing ability of smart sensor using the SAI(Sensing Ability Index) method respectively. We made the smart sensors in our experiment. The types of smart sensor are three types(H1, H1, H3 smart sensor). The smart sensors were developed for recognition of materials. Experiments and analysis were executed to estimated the sensing abili-ty of smarty sensor. Dynamic characteristics of smart sensors(acceleration changing) were evaluated respectively through a new method(SAI) that uses the power spectrum density.

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Malicious User Suppression Based on Kullback-Leibler Divergence for Cognitive Radio

  • Van, Hiep-Vu;Koo, In-Soo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.6
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    • pp.1133-1146
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    • 2011
  • Cognitive radio (CR) is considered one of the most promising next-generation communication systems; it has the ability to sense and make use of vacant channels that are unused by licensed users. Reliable detection of the licensed users' signals is an essential element for a CR network. Cooperative spectrum sensing (CSS) is able to offer better sensing performance as compared to individual sensing. The presence of malicious users who falsify sensing data can severely degrade the sensing performance of the CSS scheme. In this paper, we investigate a secure CSS scheme, based on the Kullback-Leibler Divergence (KL-divergence) theory, in order to identify malicious users and mitigate their harmful effect on the sensing performance of CSS in a CR network. The simulation results prove the effectiveness of the proposed scheme.

Automotive High Side Switch Driver IC for Current Sensing Accuracy Improvement with Reverse Battery Protection

  • Park, Jaehyun;Park, Shihong
    • Journal of Power Electronics
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    • v.17 no.5
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    • pp.1372-1381
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    • 2017
  • This paper presents a high-side switch driver IC capable of improving the current sensing accuracy and providing reverse battery protection. Power semiconductor switches used to replace relay switches are encumbered by two disadvantages: they are prone to current sensing errors and they require additional external protection circuits for reverse battery protection. The proposed IC integrates a gate driver and current sensing blocks, thus compensating for these two disadvantages with a single IC. A p-sub-based 90-V $0.13-{\mu}m$ bipolar-CMOS-DMOS (BCD) process is used for the design and fabrication of the proposed IC. The current sensing accuracy (error ${\leq}{\pm}5%$ in the range of 0.1 A-6.5 A) and the reverse battery protection features of the proposed IC were experimentally tested and verified.