• Title/Summary/Keyword: 경계 감지

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An Analysis of False Alarm Threshold Value by Heat Detector Using Heat Release Rate (열방출률을 이용한 열감지기의 오동작 경계값 분석)

  • 홍성호;김두현
    • Fire Science and Engineering
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    • v.17 no.3
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    • pp.26-30
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    • 2003
  • This paper presents a study on the analysis for false alarm of heat detector using HRR(Heat Release Rate). And it is represented to threshold value and domain of false alarm. The HRR threshold value of false alarm is calculated to use parameters obtained by small scale fire-experiment. The experiment is conducted to measure detector activation time and flame spread of wood cribs fire, etc. The results show that HRR threshold value of Fixed type detector is 20.24 kW and rate of rise type detector is 13.59 kW, respectively.

Detecting and Tracking Gaseous Objects in Video Data (화상 데이터에서 기체의 감지 및 추적)

  • 김원하
    • Proceedings of the IEEK Conference
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    • 2000.11d
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    • pp.21-24
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    • 2000
  • 기체에 대한 영상처리 기술은 그 응용 분야가 매우 넓고, 그에 따른 산업적 · 경제적 중요성도 증가되게된다 한 예로서 자동으로 공장오염 감시나 산불감시등에 사용되는 영상기기에 곧바로 기체에 대한 영상처리 기술들이 필요하다. 그러나 기체는 고체와는 다른 다음과 같은 특성들을 가지고 있다. 첫째, 고체의 경우 물체의 경계선이 비교적 분명하지만, 기체의 경우 하나의 기체 내에서도 밀도 분포가 다르기 때문에 그 경계선에서도 밀도가 불규칙하여서 기체의 경계선을 정확히 정의하기 힘들다. 둘째, 기체 분석을 위한 영상들은 대체로 잡음이 많고, 기체의 크기에 비하여 해상도가 낮다. 따라서 기체 영상은 픽셀(Pixel) 단위로 분석 처리하기가 어렵다. 위와 같은 기체가 가지는 특성 때문에 고체에 대한 영상 처리 기술을 기체에 직접적으로 적용하기는 불가능하다. 본 연구에서는 화상 데이터에서 기체를 감지하여 추적하는 시스템을 개발하고자 한다.

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A Method to Decide Thresholds of False Votes for the Effectiveness of Energy Savings in Sensor Networks (확률적 투표 여과 기법의 센서 네트워크에서 에너지 효율성을 위한 경계 값 결정 기법)

  • Nam, Su-Man;Cho, Tae-Ho
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2013.07a
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    • pp.81-82
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    • 2013
  • 무센 센서 네트워크는 개방된 환경에서 운영되기 때문에 허위 보고서와 허위 투표 삽입 공격으로부터 쉽게 노출되어 있다. 두 공격을 감지하기 위해 확률적 투표-기반 여과 기법은 보고서가 전달되는 동안 그 보고서의 투표 검증을 이용하여 허위 범위 경계 값을 통해 두 공격을 감지한다. 본 논문에서 제안 기법은 네트워크의 상황을 고려하여 센서 노드의 에너지 잔여량, 홉 수, 전달된 보고서의 수를 통해 퍼지 시스템의 입력 요소로 결정하고 나온 결과를 허위 범위 경계 값을 결정을 통해 기존 기법보다 에너지 효율을 증가시킨다. 그러므로 우리의 제안 기법은 기본 기법보다 비교했을 때 전체 네트워크 수명 연장을 기대한다.

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Study on the Contact Response analysis Technique of Marine Slender Structure (수중세장체의 접촉응답해석 기법에 관한 연구)

  • Kim, Hyung-Woo;Hong, Sup;Choi, Jong-Su;Yeu, Tae-Kyeong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.211-216
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    • 2006
  • Dynamic analysis of a marine slender structure is often involved with contacts among bodies or between bodies and seafloor. This paper presents an efficient and general contact search algorithm for dynamics in the context of the compliance contact model. A global detecting method that a bounding box is divided into several pieces in global coordinate system is presented in this paper. The method has an advantage that the number of contacting searching can be smaller than other methods for a system. The developed an efficient contact search algorithm is applied to the simulation program of 3D nonlinear dynamics of slender structure. Some examples are presented to show the validity of the proposed method.

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A Study on the Contact Response Analysis Technique for Marine Slender Structure (수중세장체의 접촉응답해석 기법에 관한 연구)

  • Hong, Sup;Choi, Jong-Su;Yeu, Tae-Kyeong;Kim, Hyung-Woo
    • Journal of Navigation and Port Research
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    • v.31 no.1 s.117
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    • pp.15-20
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    • 2007
  • Dynamic analysis of a marine slender structure is often involved with contacts among bodies or between bodies and seafloor. This paper presents an efficient and general contact search algorithm for dynamics in the context of the compliance contact model. A global detecting method that a bounding box is divided into several pieces in global coordinate system is presented in this paper. The method has an advantage that the number of contacting searching am be smaller than other methods for a system. The developed an efficient contact search algorithm is applied to the simulation program of 3D nonlinear dynamics of slender structure. Some examples are presented to show the validity of the proposed method.

ATM Cell Security Techniques Using OFB Mode on AES Block Cipher (AES 블록 암호에 OFB 모드를 적용한 ATM 셀 보안 기법)

  • Im, Sung-Yeal
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.31 no.6
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    • pp.1237-1246
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    • 2021
  • This paper is about Asynchronous Transfer Mode (ATM) cell security in which an Output Feedback (OFB) mode is applied to an AES block ciphers. ATM cells are divided into user data cells and maintenance cells, and each cell is 53 octets in size and consists of a header of 5 octets and a payload of 48 octets. In order to encrypt/decrypt ATM cells, the boundaries of cells must be detected, which is possible using the Header Error Control (HEC) field in the header. After detecting the boundary of the cell, the type of payload is detected using a payload type (PT) code to encrypt only the user cell. In this paper, a security method for ATM cells that satisfies the requirements of ISO 9160 is presented.

Statistical Analysis on Residuals from No-Fault Reference Models of a Residential Heat Pump System in Normal Cooling Operation (가정용 열펌프 시스템의 정상냉방 운전조건에서 기준모델에 의한 잔차의 통계적 분석)

  • Kim, Min-Sung;Yoon, Seok-Ho;Baik, Young-Jin
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.12
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    • pp.1351-1358
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    • 2011
  • To approximate the threshold of the fault detection and diagnosis (FDD) system, validation of the measurements is mandatory. Naturally, the system shows uncertainties due to measuring sensors - mostly thermocouples or RTDs - and due to repeatability. The uncertainty of a thermocouple comes from natural variation or a drift of the thermocouple measurement. Considering the natural variation behaves like zero-mean white noise, its natural variation can be characterized closely by the steady-state standard deviation. However, residuals between measurements and no-fault references in FDD systems show a statistical distribution with various uncertainties. In this paper, steady-state variations of measurement residuals were investigated by utilizing built-in temperature sensors in a heat pump for the model development and the final application.

Robust object tracking using projected motion and histogram intersection (투영된 모션과 히스토그램 인터섹션 기법을 이용한 강건한 물체추적)

  • 이봉석;문영식
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2000.11b
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    • pp.143-148
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    • 2000
  • 본 논문에서는 투영된 모션과 히스토그램 인터섹션을 이용한 노이즈에 강건한 물체추적 방법을 제안한다. 기존의 방법은 템플릿 매칭, 물체의 경계선 재 검출, 물체의 움직임 정보 등을 사용하여 물체추적을 하였으나, 템플릿 매칭의 경우 많은 계산 시간을 요구하며 경계선을 재 검출하는 경우 윤곽선이 잘못 설정되는 경우가 있고 물체의 움직임 정보를 사용하는 경우에는 움직이는 카메라에서 움직이는 물체만을 추적하기가 쉽지 않은 단점이 있다. 본 논문에서는 투영된 모션과 질의 영상의 템플릿 마스크를 사용하여 물체의 이동, 회전과 스케일을 고려한 노이즈에 강건한 물체추적 기법을 제안한다. 질의영상은 영상분할 후 영역선택을 통하여 구성하고 물체의 인식은 색상을 이용한 히스토그램 인터섹션 기법을 사용한다. 물체의 이동은 가로 및 세로의 밝기 값을 1차원 신호로 투영하여 개략적인 움직임을 감지하고 이동에 대한 에러를 보정하며 회전과 스케일의 변화는 질의 영상의 템플릿 마스크를 이동하여 회전과 스케일에 맞게 변경하여 감지한다

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Basic Study for performance Improvement of Fire Detectors System at Domestic Apartment Buildings (국내 공동주택 화재감지시스템의 성능개선을 위한 기초연구)

  • Son, Bong-Sae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.1
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    • pp.533-538
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    • 2014
  • This study examines the performance of and searches for improvements to the existing automatic fire detection systems installed at domestic apartment buildings as a basic study for development of intelligent fire detection systems specifically for apartments. Thus, this study aims to find out the problems in performance and maintenance of the existing fire detectors installed at apartment buildings which is the prerequisite process for development of intelligent fire detection system for that specific application. It is also found impossible to check whether or not the detectors installed at each apartment are in an operational state at normal times. This study finds that it is desirable to replace the slow-sensing heat detectors by a smoke and single smoke detectors which can detect a fire at its early stage in an effort to improve the problems of fire detectors installed at apartment buildings presently. Because we need to the independence fire detection system of apartment building.

Image Detection System for Leakage Regions of Hydraulic Fluid in Faring Press Machine (단조프레스기의 유압유 누유영역 영상 감지 시스템)

  • Bae, Sung-Ho
    • Journal of Korea Multimedia Society
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    • v.12 no.11
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    • pp.1557-1562
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    • 2009
  • In the hydraulic room of a forging press machine, a system which can detect and prevent risks at its early stage is needed because there may be a leakage due to the damage of the connection parts of the piping which can endanger human life and mechanical damage. In this paper, the system to automatically recognize a leakage of hydraulic fluid in terms of using the pan/tilt camera from a remote place is implemented. It finds the bounding boxes which are recognized with object regions in the process of labeling and detects the proper leakage regions of hydraulic fluid with the ratios of width and height of the bounding boxes and compactness of the leakage shape. Also, it performs noise removal and calibration for transition and rotation of image as a preprocessing process. The experimental results show that the proposed system has been verified to detect the leakage regions accurately in various sources of light.

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