• Title/Summary/Keyword: Detector

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The Effect of Multiple Energy Detector on Evidence Theory Based Cooperative Spectrum Sensing Scheme for Cognitive Radio Networks

  • Khan, Muhammad Sajjad;Koo, Insoo
    • Journal of Information Processing Systems
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    • v.12 no.2
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    • pp.295-309
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    • 2016
  • Spectrum sensing is an essential function that enables cognitive radio technology to explore spectral holes and resourcefully access them without any harmful interference to the licenses user. Spectrum sensing done by a single node is highly affected by fading and shadowing. Thus, to overcome this, cooperative spectrum sensing was introduced. Currently, the advancements in multiple antennas have given a new dimension to cognitive radio research. In this paper, we propose a multiple energy detector for cooperative spectrum sensing schemes based on the evidence theory. Also, we propose a reporting mechanism for multiple energy detectors. With our proposed system, we show that a multiple energy detector using a cooperative spectrum sensing scheme based on evidence theory increases the reliability of the system, which ultimately increases the spectrum sensing and reduces the reporting time. Also in simulation results, we show the probability of error for the proposed system. Our simulation results show that our proposed system outperforms the conventional energy detector system.

A Study on Feasibility Analysis and Alternatives for Infrared Detector Development (적외선 검출기 개발가능성 및 대안 분석 연구)

  • Kim, Gyeong-Su;Min, Seong-Gi;Kim, Cheol-Hwan
    • 시스템엔지니어링워크숍
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    • s.4
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    • pp.123-134
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    • 2004
  • This paper deals with the feasibility analysis and alternatives for infrared detector development. The purpose of this paper analyze development requirement and feasibility study in both technology and cost. We get raw input data for system engineering process from development and technical expert, and then analyze cost and technology for development feasibility, and alternative study. Infrared Detector is core component of Thermal Imaging System and developed by ADD from 2006 to 2008 year. Technical level is analyzed by TRL(Technical Readiness Level) and AOA(Analysis of Alternative) is done by development and production cost estimate. We use SEER-H tool for cost estimate, that is parametric cost estimate tool based on Knowledge Base. Also this paper presents risk analysis for project management because it is necessary to risk driver management during the infrared detector development. The result of IR Detector feasibility and alternative study will be used in technical and cost analysis. This study can help those who are related to the cost analysis and development feasibility of other weapons

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Effect of Coincidence Gamma-ray Spectroscopy to the Reduction of Background Spectrum

  • Kim, Taewook;Changsoo Yoou;Chongmook park;Kim, Byungtae
    • Proceedings of the Korean Nuclear Society Conference
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    • 1998.05b
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    • pp.464-469
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    • 1998
  • A coincidence gamma-ray spectroscopy method was applied to reduce the background radioactivity for measuring the activity of radioisotopes in a sample in the presence of environmental natural radioactivity. A HPGe detector was used for the coincident spectrum as a main detector and a NaI(Tl) scintillation detector for gating purposes as an associated detector. For coincidence spectroscopy the whole energy spectrum of associated detector was used instead of gate signals. The coincident events obtained from the gating spectrum was evaluated by a coincidence computer program in this study instead of timing circuit. In this work, the background of detection environment was reduced to factor 100 and peaks to be determined was reduced to factor 30 using the coincidence gamma-ray spectroscopy.

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The High Voltage Research of X-ray Detector Based on Amorphous Selenium (a-Se 기반의 X선 검출기에서의 고전장 간섭 연구)

  • Cha, Byung-Youl;Kang, Sang-Sik;Cho, Sung-Ho;Lee, Gyu-Hong;Kim, Jae-Hyung;Nam, Sang-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.853-856
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    • 2002
  • Present. direct method x-ray conversion detector is studied by abroad medical instrument and country with amorphous Selenium. And we search the method for large area x-ray detector. Amorphous-Selenium based photoreceptor is widely used on the X-ray conversion materials. But amorphous-selenium based x-ray conversion detector is broken by high voltage and leakage defect point. In this paper, We investigated top-electrode distance rate to improve defect point and high voltage broken. The result to appoint to made large area x-ray conversion detector with base data.

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A Study on the Need for Developing a Photoelectric Smoke Detector Detecting Smokes Emitted from Diverse Fire Sources (다양한 화원으로부터 발생된 연기를 감지하는 광전식연기감지기의 필요성에 대한연구)

  • Lee, Jong-Hwa
    • Journal of the Korea Safety Management & Science
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    • v.18 no.1
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    • pp.65-73
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    • 2016
  • In this paper which was performed to bring public attention to the need for developing an photoelectric smoke detector that detects smokes emitted from diverse fire sources, it was confirmed that the photoelectric smoke detector may not respond to certain smoke types depending on the size and color of smoke particles. The test was performed on a photoelectric smoke detector which is being used generally for specific fire targets specified in UL268, including paper fire, wood fire and flammable liquid fire, while the actual response performance of the fire detector, as well as respective smoke particles collected from different fire source which were photographed with a SEM(Scanning electron microscope) were analyzed in the test for this study.

Characteristics of Radiation-Resistant Real-Time Neutron Monitor for Accelerator-Based BNCT

  • Nakamura, Takemi;Sakasai, Kaoru;Nakashima, Hiroshi;Takamiya, Koichi;Kumada, Hiroaki
    • Journal of Radiation Protection and Research
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    • v.41 no.2
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    • pp.105-109
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    • 2016
  • Background: For an accelerator-based BNCT, we have fabricated a new detector consisting of quartz optical fibers that have excellent radiation-resistant characteristics. Materials and Methods: The developed detectors were irradiated at Kyoto University Research Reactor. Results and Discussion: The experimental results showed that the new detector had good output linearity for the neutron intensity, and the response of the new detector did not decrease during the irradiation. Conclusion: The new detector consisting of quartz optical fibers can be applied to measurement of neutron field of an accelerator-based BNCT.

Audio Watermarking Using Independent Component Analysis

  • Seok, Jong-Won
    • Journal of information and communication convergence engineering
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    • v.10 no.2
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    • pp.175-180
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    • 2012
  • This paper presents a blind watermark detection scheme for an additive watermark embedding model. The proposed estimation-correlation-based watermark detector first estimates the embedded watermark by exploiting non-Gaussian of the real-world audio signal and the mutual independence between the host-signal and the embedded watermark and then a correlation-based detector is used to determine the presence or the absence of the watermark. For watermark estimation, blind source separation (BSS) based on independent component analysis (ICA) is used. Low watermark-to-signal ratio (WSR) is one of the limitations of blind detection with the additive embedding model. The proposed detector uses two-stage processing to improve the WSR at the blind detector; the first stage removes the audio spectrum from the watermarked audio signal using linear predictive (LP) filtering and the second stage uses the resulting residue from the LP filtering stage to estimate the embedded watermark using BSS based on ICA. Simulation results show that the proposed detector performs significantly better than existing estimation-correlationbased detection schemes.

Development Can Air Leak Detector System For Single Compression Head-Line Type Using Pressure Sensor (압력 센서를 이용한 씽글 헤드라인 타입의 캔 에어 리크 검출씨스템 개발)

  • Lee, Jong-Woon
    • Proceedings of the KIEE Conference
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    • 1992.07a
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    • pp.506-507
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    • 1992
  • When it comes to the 'Leak Detector System' generally, our country has a large income 'Rotary Type Leak Detector' of foreign goods. The completed development of the 'Line Type Leak-Detector' system was produced to check Whether the containers for small and large on the filling line are auto defective. This system is applied to the filling package Processing during the production and contributed to inproving competiveness of domestic containers manufactures of all society of Industry. Also, high precision and realiablity, very compact size, low cost and Easy set-up etc. by checking the experimental data directly plan, Design and making for '1 Compression Head Control Leak Detector System'. This flexcible system can be equipped with multiple Compression heads depending on the requested prodution test rate and test precision.

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Lane Detection Using Biased Discriminant Analysis

  • Kim, Tae Kyung;Kwak, Nojun;Choi, Sang-Il
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.3
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    • pp.27-34
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    • 2017
  • We propose a cascade lane detector that uses biased discriminant analysis (BDA) to work effectively even when there are various external factors on the road. The proposed cascade detector was designed with an existing lane detector and the detection module using BDA. By placing the BDA module in the latter stage of the cascade detector, the erroneously detected results by the existing detector due to sunlight or road fraction were filtered out at the final lane detection results. Experimental results on road images taken under various environmental conditions showed that the proposed method gave more robust lane detection results than conventional methods alone.

Sampling Phase Detector for NRZ Random Bit Synchronization (NRZ Random Bit 동기를 위한 표본 위상 검출기)

  • 박세현;박세훈
    • Journal of Korea Multimedia Society
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    • v.3 no.6
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    • pp.652-660
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    • 2000
  • This paper proposes a new type of sampling Phase Detector (SPD) for NRZ random bit synchronization circuit. The proposed SPD calculates the mean value of phase difference between bit interval of input signal and period of local reference. Simulated and experimental results show that the proposed SPD is applicable to the phase detector for NRZ random signal. finally the Random NRZ bit synchronization circuit. is designed and implemented by using SPD.

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