• Title/Summary/Keyword: 충돌 탐지

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Simplified Module Based Self-collision Detection for Humanoid Robots (간략화 된 모듈 기반의 휴머노이드 로봇을 위한 자기충돌 탐지)

  • Kwak, Hwan-Joo;Park, Gwi-Tae
    • Proceedings of the KIEE Conference
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    • 2008.04a
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    • pp.240-241
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    • 2008
  • We are presenting the efficient and robust simplified module based self-collision detection of humanoid robot simulator. For safe and reliable operations of humanoid robot, the self-collision detection is essential and extremely important. The main methods of self-collision detection are inverse X-Y-Z fixed angles and module distance filtering (MDF). According to experiments on the humanoid robot simulator with the self-collision detection, we could have a confidence about the efficiency of the self-collision.

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첨단과학현장 - 생활현장으로 진출하는 레이더

  • Hyeon, Won-Bok
    • The Science & Technology
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    • v.29 no.12 s.331
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    • pp.67-70
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    • 1996
  • 전파의 반사로 대상체의 위치를 측정하는 레이더는 2차대전 이래 사용되어 온 오랜 기술이다. 본시 적의 항공기나 선박을 탐지하는 군사용으로 개발된 레이더는 차츰차츰 민생용으로 전환되면서 항공기와 선박들은 이 기술을 이용하여 충돌을 피하는가 하면 천문학자들은 천체의 표면을 그리는데 사용하고 기상전문가들은 이 기술을 이용하여 폭풍을 추적한다. 그러나 몇해 전만해도 담배값 크기의 싼 개인용레이더가 등장하여 인간활동의 구석구석까지 침투할 것이라고 예상한 사람은 거의 없었다.

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NEWS & TOPIC

  • Korean Federation of Science and Technology Societies
    • The Science & Technology
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    • v.35 no.11 s.402
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    • pp.6-9
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    • 2002
  • 스웨덴 왕립아카데미 노벨상 수상자 발표/암세포에 꼬리를 단다/극초음속 순항 미사일 엔진 개발/염소 고환조직, 쥐에 이식하여 정자생성/인간의 언어 유전자 발견/도마뱀이 천장을 기어다니는 비밀은 미세한 털/공룡 단백질 재생/지구, 알려진 것보다 3천만년전 태양계 편입/ 남극에 암흑에너지 탐지용 망원경 설치/약 35억년전 거대 소행성이 지구에 충돌/말라리아 원충 모기 유전자 해독/반물질인 반수소 대량 생산

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Track-Before-Detect Algorithm for Multiple Target Detection (다수 표적 탐지를 위한 Track-Before-Detect 알고리듬 연구)

  • Won, Dae-Yeon;Shim, Sang-Wook;Kim, Keum-Seong;Tahk, Min-Jea;Seong, Kie-Jeong;Kim, Eung-Tai
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.39 no.9
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    • pp.848-857
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    • 2011
  • Vision-based collision avoidance system for air traffic management requires a excellent multiple target detection algorithm under low signal-to-noise ratio (SNR) levels. The track-before-detect (TBD) approaches have significant applications such as detection of small and dim targets from an image sequence. In this paper, two detection algorithms with the TBD approaches are proposed to satisfy the multiple target detection requirements. The first algorithm, based on a dynamic programming approach, is designed to classify multiple targets by using a k-means clustering algorithm. In the second approach, a hidden Markov model (HMM) is slightly modified for detecting multiple targets sequentially. Both of the proposed approaches are used in numerical simulations with variations in target appearance properties to provide satisfactory performance as multiple target detection methods.

Underwater Noise Measurements on the Immersed Hydrofoil of High-Speed Vessel (고속 선박의 몰수된 hydrofoil에서 수중 소음 계측)

  • Park, Ji-Yong;Lee, Keun-Hwa;Seong, Woo-Jae
    • The Journal of the Acoustical Society of Korea
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    • v.30 no.1
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    • pp.9-16
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    • 2011
  • When a hydrofoil ship plies at high speed, there exist possibilities of collision with ocean mammals dwelling near the surface. An active sonar located within the immersed hydrofoil structure that provides the lift for the vessel, can be used for early warning of their presence. The proper functioning of the active sonar system depends on its ability to reject noise and pick up the target signal. In this article, we measured the noise on a hydrofoil of an operating ship with two flush-mounted hydrophones. The measurements were conducted for the purpose of (1) identifying the effect of operating state of machinery likes engine, cooler and generator (2) observing the change of noise depending on the measuring position (3) observing the change of noise with increasing ship speed. To verify our experiment, experiments were performed three times and the measured results are compared with other investigations and they show similarity to each other. The results are analyzed with frequency domain in order to apply to operating active sonar detecting system and focus on high frequency band within sonar's operating frequency region. Through these experiments and analysis, it is expected that we can identify the generated noise around hydrofoil where active sonar is installed and these results lead us to design active sonar that could distinguish target signal from noise more effectively.

Automatic Merging of Distributed Topic Maps based on T-MERGE Operator (T-MERGE 연산자에 기반한 분산 토픽맵의 자동 통합)

  • Kim Jung-Min;Shin Hyo-Pil;Kim Hyoung-Joo
    • Journal of KIISE:Software and Applications
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    • v.33 no.9
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    • pp.787-801
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    • 2006
  • Ontology merging describes the process of integrating two ontologies into a new ontology. How this is done best is a subject of ongoing research in the Semantic Web, Data Integration, Knowledge Management System, and other ontology-related application systems. Earlier research on ontology merging, however, has studied for developing effective ontology matching approaches but missed analyzing and solving methods of problems of merging two ontologies given correspondences between them. In this paper, we propose a specific ontology merging process and a generic operator, T-MERGE, for integrating two source ontologies into a new ontology. Also, we define a taxonomy of merging conflicts which is derived from differing representations between input ontologies and a method for detecting and resolving them. Our T-MERGE operator encapsulates the process of detection and resolution of conflicts and merging two entities based on given correspondences between them. We define a data structure, MergeLog, for logging the execution of T-MERGE operator. MergeLog is used to inform detailed results of execution of merging to users or recover errors. For our experiments, we used oriental philosophy ontologies, western philosophy ontologies, Yahoo western philosophy dictionary, and Naver philosophy dictionary as input ontologies. Our experiments show that the automatic merging module compared with manual merging by a expert has advantages in terms of time and effort.

Collision Risk Assessment by using Hierarchical Clustering Method and Real-time Data (계층 클러스터링과 실시간 데이터를 이용한 충돌위험평가)

  • Vu, Dang-Thai;Jeong, Jae-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.4
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    • pp.483-491
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    • 2021
  • The identification of regional collision risks in water areas is significant for the safety of navigation. This paper introduces a new method of collision risk assessment that incorporates a clustering method based on the distance factor - hierarchical clustering - and uses real-time data in case of several surrounding vessels, group methodology and preliminary assessment to classify vessels and evaluate the basis of collision risk evaluation (called HCAAP processing). The vessels are clustered using the hierarchical program to obtain clusters of encounter vessels and are combined with the preliminary assessment to filter relatively safe vessels. Subsequently, the distance at the closest point of approach (DCPA) and time to the closest point of approach (TCPA) between encounter vessels within each cluster are calculated to obtain the relation and comparison with the collision risk index (CRI). The mathematical relationship of CRI for each cluster of encounter vessels with DCPA and TCPA is constructed using a negative exponential function. Operators can easily evaluate the safety of all vessels navigating in the defined area using the calculated CRI. Therefore, this framework can improve the safety and security of vessel traffic transportation and reduce the loss of life and property. To illustrate the effectiveness of the framework proposed, an experimental case study was conducted within the coastal waters of Mokpo, Korea. The results demonstrated that the framework was effective and efficient in detecting and ranking collision risk indexes between encounter vessels within each cluster, which allowed an automatic risk prioritization of encounter vessels for further investigation by operators.

Intrusion Detection System Based on Sequential Model in SOME/IP (SOME/IP 에서의 시퀀셜 모델 기반 침입탐지 시스템)

  • Kang, Yeonjae;Pi, Daekwon;Kim, Haerin;Lee, Sangho;Kim, Huy Kang
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.32 no.6
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    • pp.1171-1181
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    • 2022
  • Front Collision-Avoidance Assist (FCA) or Smart Cruise Control (SCC) is installed in a modern vehicle, and the amount of data exchange between ECUs increases rapidly. Therefore, Automotive Ethernet, especially SOME/IP, which supports wide bandwidth and two-way communication, is widely adopted to overcome the bandwidth limitation of traditional CAN communication. SOME/IP is a standard protocol compatible with various automobile operating systems, and improves connectivity between components in the vehicle. However, no encryption or authentication process is defined in the SOME/IP protocol itself. Therefore, there is a need for a security study on the SOME/IP protocol. This paper proposes a deep learning-based intrusion detection system in SOME/IP and performs six attacks to confirm the performance of the intrusion detection system.

Hierarchical Delegation Model for Network Security Management (네트워크 보안 관리를 위한 계층적 위임 모델)

  • 이강희;송병욱;배현철;김장하;김상욱
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04a
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    • pp.238-240
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    • 2004
  • 본 논문에서는 대규모 네트워크 보안관리를 위한 계층적인 위임 모델을 제시한다. 대규모 네트워크는 라우터, 방화벽, 침입 탐지 시스템, 웹 서버 등의 수많은 구성요소로 이루어진 네트워크들의 집합이며, 각 네트워크마다의 독립적인 지역 정책들로 관리되어 서로간의 협동이 이루어질 수 없기 때문에 이를 효과적으로 통제하고 일괄적으로 관리하기 위해 계층적인 위임 모델이 사용되어야 한다. 제시하는 모델의 중요 구성 요소로는 관리 서버. 정책 설정 고 수준 언어 고 수준 언어 컴파일러, 도메인 서버. 인터프리터, 정책 관리 데이터베이스가 있다. 관리 서버에서 정책 설정 고 수준 언어를 사용하여 세밀하고 정교한 정책을 작성할 수 있고, 이 정책을 고 수준 언어 컴파일러를 통하여 최하위 노드들에게 적절하고 간결한 형태로 만들어낸다. 각 도메인 서버는 이 결과를 하위의 도메인 서버나 인터프리터에게 전달하면서 Keynote 신뢰 관리 시스템을 이용하여 권한을 위임한다. 그리고 인터프리터는 정책을 라우터, 방화벽, 웹 서버 등의 하위 노드에 맞는 실제 룰로 변환하녀 상위 관리 서버에서 전달한 정책을 적용하게 된다. 정책을 적용한 결과를 상위로 전달하여 데이터베이스를 구축한 뒤 후에 작성된 정책이 기존의 정책과 충돌하는지 검사에 이용하고, 충돌한다면 협상 과정을 거쳐 정책에 순응할 수 있는 결과를 도굴하게 된다. 또한 네트워크에서 많은 새로운 형태들의 노드가 추가될 수 있는데, 각각의 인터프리터만 추가함으로서 다양한 하위 노드를 충족시킬 수 있는 확장성을 제공한다.

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Analysis of Radar Recognition Characteristics of Bridge Piers and Attachments for Safe Passing (교량 안전통항을 위한 레이더의 교각인식 특성 분석)

  • Kim Tain-In;Park Sang Il;Jeong Deuk Dae;Shin Chul Ho
    • Proceedings of KOSOMES biannual meeting
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    • 2003.11a
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    • pp.59-65
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    • 2003
  • For safe passing the waterway crossing bridge without collision with bridge-piers under poor visibility circumstances, it is very important that the pier should be detected definitely as earlier as possible by radar, In this study, the required length of Projecting part of the bridge pier for definite radar recognition was obtained by theoretical and experimental analyses. By presenting the required values depending on the maximum vessel size and passing condition, it is expected possible to design the bridge pier protecting system appropriately suitable to traffic environment of the waterway.

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