• 제목/요약/키워드: Detect

검색결과 14,759건 처리시간 0.037초

레이저 스캐너의 틸트 각도 조절을 통한 다양한 환경에서의 연석 탐지 및 추종 (Curb Detection and Following in Various Environments by Adjusting Tilt Angle of a Laser Scanner)

  • 이동욱;이용주;송재복;백주현;유재관
    • 제어로봇시스템학회논문지
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    • 제16권11호
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    • pp.1068-1073
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    • 2010
  • When a robot navigates in an outdoor environment, a curb or a sidewalk separated from the road can be used as a robust feature. However, most algorithms could detect the curb only in the straight road, and could not detect highly curved corners, ramps, and so on. This paper proposes an algorithm which enables the robot to detect and follow the curbs in various types of roads. In the proposed method, the robot tilts a laser scanner and computes the error between the predicted and the measured distances to the road in front of the robot. Based on this error, the curbs at corners and curves can be classified. It is also difficult to detect a curb near a ramp because of its low height. In this case, the robot also tilts a laser scanner to detect the curb beyond the ramp. Once the robot classifies the road into the curve, corner, ramp, the robot selects the proper navigation strategies depending on the classified road types and is able to continue to detect and follow the curb. The results of a series of experiments show that the robot can stably detect and follows the curb in curves, corners and ramps as well as the straight road.

메모리 실행영력 추적을 사용한 버퍼오버플로 악성코드 탐지기법 (Buffer Overflow Malicious Code Detection by Tracing Executable Area of Memory)

  • 최성운;조재익;문종섭
    • 정보보호학회논문지
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    • 제19권5호
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    • pp.189-194
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    • 2009
  • 버퍼오버플로 악성코드 탐지를 위해 대부분의 안티바이러스 프로그램은 공격코드의 시그너처만 비교 탐지하고 있어 알려지지 않은 공격코드에 대해 탐지하지 못하는 문제점이 있다. 본 논문에서는 공격코드에서 필수적으로 사용하는 API의 메모리 실행영역 추적기법을 이용하여 알려지지 않은 공격코드에 대한 탐지기법을 제안한다. 제윤기법 검증을 위해 7개의 샘플 공격코드를 선정하여 8개의 안티바이러스 프로그램과 비교 실험한 결과, 대부분의 안티바이러스 프로그램은 Stack영역만 감시하고 Heap영역은 감시하지 않아 제안적인 탐지만 가능하였다. 이에 대부분의 안티 바이러스 프로그램에서 탐지할 수 없는 공격코드를 제안 기법을 이용하여 탐지할 수 있음을 시뮬레이션 하였다.

가열유(加熱乳)의 검출법(檢出法) (Detection Method of Heated Milk)

  • 이부웅;장운기;김태화;허문영
    • Journal of Dairy Science and Biotechnology
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    • 제22권2호
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    • pp.113-118
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    • 2004
  • 가열유는 rennet 응고성, 전자현미경법, -SH기정량, 전기영동적 관찰법, 340nm에서 흡광도 측정법 등 여러 가지 방법에 의하여 판정이 가능하나 간편성, 신속성으로 보아 rennet 응고성 이용이 가장 돌출하다. 70도 이상의 가열유는 rennet 응고성을 이용하여 판정이 가능하다. 앞으로 $55^{\circ}C$ 부근의 예열 수준도 검출할 수 있는 방법이 더 개발되어야 한다.

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광학적 시간영역 반사시스템을 이용한 모르타르 보의 균열 탐사 (Crack Detection in Mortar Beams using Optical Time Domain Reflectometry)

  • 임홍철;이경근
    • 한국구조물진단유지관리공학회 논문집
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    • 제4권3호
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    • pp.185-195
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    • 2000
  • Detection of cracks in concrete beams using optical fiber sensors is useful for monitoring of concrete structures. In this study, optical time domain reflectometry (OTDR) is used to detect cracks. Resolution of OTDR is the main contributor to detect cracks in concrete structures. The OTDR used in this study can detect cracks with high precision of 0.5 m. Two mortar beams, reinforced with a 19 mm diameter steel bar, are made with the dimensions of 140 mm (width) ${\times}$ 200 mm (depth) ${\times}$ 2.000 mm (length). Two fibers are embedded inside each beam and two fibers are attached under the beams. The application of measurement system which consists of fiber and FC/PC connecter is studied. For this, theory of optics, resolution, crack moment, and size of specimens are investigated. From the measured data, it is verified that fibers which are attached under the beam can detect the crack in beams effectively. However, fibers embedded inside the beam are unable to detect cracks in beams using the OTDR in this study.

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t-ws 고장 검출을 위한 테스트 방법의 개선 (Improvement of Test Method for t-ws Falult Detect)

  • 김철운;김영민;김태성
    • E2M - 전기 전자와 첨단 소재
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    • 제10권4호
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    • pp.349-354
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    • 1997
  • This paper aims at studying the improvement of test method for t-weight sensitive fault (t-wsf) detect. The development of RAM fabrication technology results in not only the increase at device density on chips but also the decrease in line widths in VLSI. But, the chip size that was large and complex is shortened and simplified while the cost of chips remains at the present level, in many cases, even lowering. First of all, The testing patterns for RAM fault detect, which is apt to be complicated , need to be simplified. This new testing method made use of Local Lower Bound (L.L.B) which has the memory with the beginning pattern of 0(l) and the finishing pattern of 0(1). The proposed testing patterns can detect all of RAM faults which contain stuck-at faults, coupling faults. The number of operation is 6N at 1-weight sensitive fault, 9,5N at 2-weight sensitive fault, 7N at 3-weight sensitive fault, and 3N at 4-weight sensitive fault. This test techniques can reduce the number of test pattern in memory cells, saving much more time in test, This testing patterns can detect all static weight sensitive faults and pattern sensitive faults in RAM.

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Water Detection in an Open Environment: A Comprehensive Review

  • Muhammad Abdullah, Sandhu;Asjad, Amin;Muhammad Ali, Qureshi
    • International Journal of Computer Science & Network Security
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    • 제23권1호
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    • pp.1-10
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    • 2023
  • Open surface water body extraction is gaining popularity in recent years due to its versatile applications. Multiple techniques are used for water detection based on applications. Different applications of Radar as LADAR, Ground-penetrating, synthetic aperture, and sounding radars are used to detect water. Shortwave infrared, thermal, optical, and multi-spectral sensors are widely used to detect water bodies. A stereo camera is another way to detect water and different methods are applied to the images of stereo cameras such as deep learning, machine learning, polarization, color variations, and descriptors are used to segment water and no water areas. The Satellite is also used at a high level to get water imagery and the captured imagery is processed using various methods such as features extraction, thresholding, entropy-based, and machine learning to find water on the surface. In this paper, we have summarized all the available methods to detect water areas. The main focus of this survey is on water detection especially in small patches or in small areas. The second aim of this survey is to detect water hazards for unmanned vehicles and off-sure navigation.

하드웨어 고장 검출을 위한 행위레벨 설게에서의 테스트패턴 생성 (High level test generation in behavioral level design for hardware faults detection)

  • 김종현;윤성욱;박승규;김동욱
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 하계종합학술대회논문집
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    • pp.819-822
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    • 1998
  • The high complexity of digital circuits has changed the digital circuits design mehtods from schemeatic-based to hardware description languages like VHDL, verilog that make hardware faults become more hard to detect. Thus test generation to detect hardware defects is very important part of the design. But most of the test generation methods are gate-level based. In this paper new high-level test generation method to detect stuck-at-faults on gate level is described. This test generation method is independent of synthesis results and reduce the time and efforts for test generation.

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Intensity차를 이용한 차선의 위치 검출에 관한 연구 (A Study on the Estimation of Lane position using difference of Intensity)

  • 손경희;송현승;노도환
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.403-403
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    • 2000
  • Generally estimation of driving direction uses the way which uses lane detection and vanishing point in autonomous-driving system. Especially we use Sub-window for decreasing Process time when we detect lane, but fixed sub-window can not detect lane because of some factors in road image. So we suggest algorithm using one-dimension line scan method to detect an exact position of lane.

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Scene Change Detection Algorithm on Compressed Video

  • Choi Kum-Su;Moon Young-Deuk
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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    • pp.442-446
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    • 2004
  • This paper propose scene change detection algorithm using coefficient of forward prediction macro-block, backward prediction macro-block, and intra-coded macro-block on getting motion estimation. Proposed method detect scene change with correlation according picture type forward two picture or forward and backward two picture on video sequences. Proposed algorithm is high accuracy and can detect all scene change on video, and detect to occur scene change on P, B, I-picture.

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비접촉식 전류 검출 장치에 관한 연구 (A Study on the Current Detector with Non Contact Type)

  • 김기준
    • 한국전기전자재료학회논문지
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    • 제31권5호
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    • pp.351-356
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    • 2018
  • Commonly, a live-line alarm can be used to measure the electric field strength of a high-voltage system to calculate its current, but it is hard to detect the electric field of shielded cables or concealed structures, such as underground distribution cables. Current sensors can detect the magnetic field in a single core wire, but they cannot determine the magnetic field about a double-core wire because the currents flow in opposite directions. Therefore, it is very difficult to detect certain current problems, such as a fault current in an extension line comprised of a double line. In this paper, to ultimately develop a sensor that can detect the current regardless of line conditions, we used a simulation to determine the concentration of the magnetic field dependent on the distribution of the external magnetic field and the path of each line's core.