• 제목/요약/키워드: Collision behavior

검색결과 259건 처리시간 0.037초

재료모델에 따른 유연 콘크리트 매트리스의 충돌 거동 평가 (Collision Behavior Evaluation of Flexible Concrete Mattress Depending on Material Models)

  • 류연선;조현만;김서현
    • 한국해양공학회지
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    • 제29권1호
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    • pp.70-77
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    • 2015
  • The purpose of this study was to provide fundamental data for an anchor collision simulation of an FCM (flexible concrete mattress). Numerical material models (elastic-perfectly plastic model, Drucker-Prager model, and RHT concrete model) were compared. ANSYS Explicit Dynamics was used for collision analyses. An FE model was used for the anchor, FCM, andreinforcement bars. The results showed that the behavior of the FCM was verydifferent that those ofthe material models. In particular, the effect of the pressure dependent strength was most noticeable among the properties of concrete.

전방 충돌경보 및 회피시스템 모델링 (Modeling of Forward Collision Warning and Avoidance System)

  • 오병근;조남효
    • 한국군사과학기술학회지
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    • 제3권2호
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    • pp.156-165
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    • 2000
  • This paper describes modeling and simulation of automotive forward collision warning and avoidance system using CASE(Computer-Aided Systems Engineering) tool. The system is composed or many sensors, a controller, warning devices, brakes and etc. The system was modeled by one activity chart, fourteen state charts and one module chart. Rear-end collision scenarios was generated by Simulink and used to support Stalemate model. The resulting model was used to evaluate the correctness of function and behavior of the system. A simulator for the system has been designed and used to validate the model under realistic operating conditions in the laboratory. To model and simulate the system's functionality and behavior brings clarity to system design early in the system development.

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철근의 영향과 앵커 충돌각도를 고려한 유연콘크리트 매트리스의 손상평가 (Damage Evaluation of Flexible Concrete Mattress Considering Steel Reinforcement Modeling and Collision Angle of Anchor)

  • 류연선;조현만;김서현
    • 한국해양공학회지
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    • 제30권2호
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    • pp.109-116
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    • 2016
  • A flexible concrete mattress (FCM) is a structural system for protecting submarine power or communication cables under various load types. To evaluate its of protection performance, a numerical analysis of an FCM under an anchor collision was performed. The explicit dynamics of the finite element analysis program ANSYS were used for the collision analysis. The influences of the steel reinforcement modeling and collision angle of the anchor on the collision behavior of the FCM were estimated. The FCM damage was evaluated based on the results of the numerical analysis considering the numerical modeling and collision environment.

선박의 회전거동을 고려한 3자유도 충돌모델 (3 DOFs bridge-vessel collision model considering with rotation behaviors of the vessel)

  • 이계희;이성로
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2008년도 정기 학술대회
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    • pp.380-385
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    • 2008
  • 3 DOFs model for the collision analysis of a bridge super-structure and a super-structure of the navigating vessels were proposed and analyzed. The collision event between the super-structure of vessel and the super-structure of bridge are different from the normal collision event that collided at sub-structure of bridge. Because of its moment arm, the stability force of vessel could affect to the collision behaviors. To consider this effect, 3 DOFs model including two translation DOFs and one rotational DOF were introduced. The restoration forces of the collision system were considered as nonlinear springs. The equations of motion were derived if form of differential equations and numerically solved by 4th order Runge-Kutta method. The accuracy and the feasibility of this model were verified by the numerical example with parameter of moment arm length.

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직교좌표계 가속도 외란 추정을 통한 충돌 감지 알고리즘 개발 (Development of Collision Detection Method Using Estimation of Cartesian Space Acceleration Disturbance)

  • 정병진;문형필
    • 로봇학회논문지
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    • 제12권3호
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    • pp.258-262
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    • 2017
  • In this paper, we propose a new collision detection algorithm for human-robot collaboration. We use an IMU sensor located at the tip of the manipulator and the kinematic behavior of the manipulator to detect the unexpected collision between the robotic manipulator and environment. Unlike other method, the developed algorithm uses only the kinematic relationship between the manipulator joint and the end effector. Therefore, the collision estimation signal is not affected by the error of the dynamics model. The proposed collision detection algorithm detects the collision by comparing the estimated acceleration of the end effector derived from the position, velocity and acceleration trajectories of the robot joints with the actual acceleration measured by the sensor. In simulation, we compare the performance of our method with the conventional Residual Observer (ROB). Our method is less sensitive to the load variation because of the independency on the dynamic modeling of the manipulator.

A Simple and Fast Anti-collision Protocol for Large-scale RFID Tags Identification

  • Jia, Xiaolin;Feng, Yuhao;Gu, Yajun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권4호
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    • pp.1460-1478
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    • 2020
  • This paper proposes a novel anti-collision protocol for large-scale RFID tags identification, named Bi-response Collision Tree Protocol (BCT). In BCT, two group of tags answer the reader's same query in two response-cycles respectively and independently according to the bi-response pattern. BCT improves the RFID tag identification performance significantly by decreasing the query cycles and the bits transmitted by the reader and tags during the identification. Computation and simulation results indicate that BCT improves the RFID tag identification performance effectively, e.g. the tag identification speed is improved more than 13.0%, 16.9%, and 22.9% compared to that of Collision Tree Protocol (CT), M-ary Collision Tree Protocol (MCT), and Dual Prefix Probe Scheme (DPPS) respectively when tags IDs are distributed uniformly.

연료 제트의 두 액적간의 충돌기구에 관한 실험적 연구 (Experimental Investigation of Collision Mechanisms Between Binary Droplet of Fuel Jet)

  • 이근희;김사엽;이창식
    • 한국분무공학회지
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    • 제13권4호
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    • pp.187-192
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    • 2008
  • In this study, the mechanisms of binary droplet collision were studied with diesel, ethanol and purified water. The droplet collisions of liquid droplet have been investigated for the same droplet diameter. In order to obtain the digital images of the droplet collision behavior, the experimental equipment was composed of the droplet generating system and the droplet visualization system. The droplets were produced by the vibrating orifice monodisperse generator. The visualization system consisted of a long distance microscope, a light source, and a high speed camera. The outcomes of binary droplet collision can be divided into four regimes, bouncing, coalescence, reflexive separation and stretching separation. The impact angle and the relative velocity of binary droplet are main parameters of collision phenomena, so the transition mechanism of droplet collision can be divided by the impact parameter.

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Observation of Electrocatalytic Amplification of Iridium Oxide (IrOx) Single Nanoparticle Collision on Copper Ultramicroelectrodes

  • Choi, Yong Soo;Jung, Seung Yeon;Joo, Jin Woo;Kwon, Seong Jung
    • Bulletin of the Korean Chemical Society
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    • 제35권8호
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    • pp.2519-2522
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    • 2014
  • Recently, the observation of the electrocatalytic behavior of individual nanoparticles (NPs) by electrochemical amplification method has been reported. For example, the Iridium oxide ($IrO_x$) NP collision on the Pt UME was observed via electrocatalytic water oxidation. However, the bare Pt UME had poor reproducibility for the observation of NP collision signal and required an inconvenient surface pre-treatment for the usage. In this manuscript, we has been investigated other metal electrode such as Cu UME for the reproducible data analysis and convenient use. The $IrO_x$ NP collision was successively observed on the bare Cu UME and the reproducibility in collision frequency was improved comparing with previous case using the $NaBH_4$ pre-treated Pt UME. Also, the adhesion coefficient between NP and the Cu UME was studied for better understanding of the single NP collision system.

Examination of the Fragmentation Behavior of Hemin and Bilin Tetrapyrroles by Electrospray Ionization and Collision-induced Dissociation

  • Sekera, Emily R.;Wood, Troy D.
    • Mass Spectrometry Letters
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    • 제9권4호
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    • pp.91-94
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    • 2018
  • Bilin tetrapyrroles are metabolic products of the breakdown of porphyrins within a species. In the case of mammals, these bilins are formed by the catabolism of heme and can be utilized as either biomarkers in disease or as an indicator of human waste contamination. Although a small subset of bilin tandem mass spectrometry reports exist, limited data is available in online databases for their fragmentation. The use of fragmentation data is important for metabolomics analyses to determine the identity of compounds detected within a sample. Therefore, in this study, the fragmentation of bilins generated by positive ion mode electrospray ionization is examined by collision-induced dissociation (CID) as a function of collision energy on an FT-ICR MS. The use of the FT-ICR MS allows for high mass accuracy measurements, and thus the formulas of resultant product ions can be ascertained. Based on our observations, fragmentation behavior for hemin, biliverdin and its dimethyl ester, phycocyanobilin, bilirubin, bilirubin conjugate, mesobilirubin, urobilin, and stercobilin are discussed in the context of the molecular structure and collision energy. This report provides insight into the identification of structures within this class of molecules for untargeted analyses.