• Title/Summary/Keyword: Collisions

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The design of fuzzy collision avoidance expert system implemented by Matlab fuzzy logic toolbox

  • Ganlkhagva, Munkhtulga;Jeong, Jae-Yong;Jeong, Jung-Sik
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2011.11a
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    • pp.34-36
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    • 2011
  • In recent years, shipping at the sea has been rapidly grown in marine nations and vessel's collisions are increasing as well. The collision avoidance is one of issues maritime safety. To reduce vessels' collisions, the fuzzy inference system is one of popular algorithms for collision avoidance. In this paper we aim to implement Matlab. Fuzzy logic toolbox software for collision avoidance algorithm. For this we used an original Matlab fuzzy logic toolbox and customized the toolbox for the collision avoidance algorithm.

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Mitigation Techniques of Channel Collisions in the TTFR-Based Asynchronous Spectral Phase-Encoded Optical CDMA System

  • Miyazawa, Takaya;Sasase, Iwao
    • Journal of Communications and Networks
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    • v.11 no.1
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    • pp.1-10
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    • 2009
  • In this paper, we propose a chip-level detection and a spectral-slice scheme for the tunable-transmitter/fixed-receiver (TTFR)-based asynchronous spectral phase-encoded optical codedivision multiple-access (CDMA) system combined with timeencoding. The chip-level detection can enhance the tolerance of multiple access interference (MAI) because the channel collision does not occur as long as there is at least one weighted position without MAI. Moreover, the spectral-slice scheme can reduce the interference probability because the MAI with the different frequency has no adverse effects on the channel collision rate. As a result, these techniques mitigate channel collisions. We analyze the channel collision rate theoretically, and show that the proposed system can achieve a lower channel collision rate in comparison to both conventional systems with and without the time-encoding method.

Theory of Coagulation(I) Coagulation Theory Including Hydrodynamics and Interparticle Forces (응집의 이론 (I) - 수리동역학과 입자간 작용력을 고려한 응집의 모델 -)

  • Han, Moo Young
    • Journal of Korean Society of Water and Wastewater
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    • v.9 no.3
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    • pp.65-77
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    • 1995
  • The kinetics of flocculation of heterodisperse suspension like those in water treatment plants and natural water system are usually described by the Smoluchowski equation, which incorporates collision frequency functions for particle collisions by Brownian motion, fluid shear, and differential sedimentation. These collisionfrequeney functions have been based on a rectilinear view of collisions, i.e., one that ignores short-range forces and changes in fluid motion as particles approach one another. In this research, a curvilinear approach, i.e., one that accounts for hydrodynamic forces and particle interaction in the collision of two different size particles is developed. Collision efficiency factors of each mechanism can be calculated by trajectory analysis (fluid shear and differential sedimentation) or the solution of diffusion equation (Brownian motion). The results are presented as a set of corrections to the rectilinear collision frequency functions for each mechanism.

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A Parameter-Based Hairstyler (패러미터 기반 머리카락 모델링 기법)

  • Choe, Byoung-Won;Ko, Hyeong-Seok
    • Journal of the Korea Computer Graphics Society
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    • v.10 no.2
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    • pp.10-16
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    • 2004
  • This paper presents an interactive technique that produces static human hairstyles by generating individual hair strands of the desired shape and color, subject to the presence of gravity and collisions. A variety of human hairstyles can be generated by supplying a few parameters to the modeling core, which consists of the wisp generator and hair deformation solver. Wisps are generated employing statistical approaches. As for hair deformation, a method that is not physically-based is proposed to efficiently account for the effects of gravity and collisions. The technique produces various hairstyles much faster than previously proposed methods, and the styles generated by this technique are remarkably realistic.

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THE DYNAMICAL STRUCTURES OF DENSE MOLECULAR CLOUDS IN THE GALACTIC CENTER REGION & THEIR IMPLICATIONS

  • LEE C. W.;LEE H. M.;ANN H. B.;KWON K. H.
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.161-163
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    • 1996
  • We have studied the response of molecular clouds in the Galactic disk to a rotating bar by conducting Smoothed Particle Hydrodynamics (SPH) simulations for the Galaxy in order to understand the dynamical structures of the Galactic Center (GC) molecular clouds, and their implications. In our study it was found that the structures of GC molecular clouds could be induced by the combined effects of rotating bar potential, the hydrodynamic collisions and gravitational miss collisions between the clouds.

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The effect of driver's sex and age on human responsible involvement in two-car crashes

  • Park, S.G.
    • Journal of the Ergonomics Society of Korea
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    • v.11 no.1
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    • pp.111-118
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    • 1992
  • Assuming the majority of car accidents are due to driver errors, we due rear-end collisions which occurred in the State of Washington, USA, in 1982, 1983, and 1984, to study human responsible involvement associated with the sex and age of drivers. Rear-end collisions involving two passenger cars are included in this study. The driver of a car which struck the rear end of another car is considered responsible for the accident, and the driver of a car which was struck in the rear end is not considered responsible for the accident. In addition to male and female drivers, we used three different age groups: 16 to 24 years old, 25 to 34 years old, and 35 years or older. Hence, six diferent groups of drivers are considered in this study.

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Development of Whistle Signal Reception and Alert System for Small Vessel (소형선박용 기적경고신호 수신.경보시스템 개발)

  • Moon, Serng-Bae;Oh, Jin-Seok;Jun, Seung-Hwan;Yang, Hyoung-Seon;Jeong, Eun-Seok
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.8
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    • pp.990-997
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    • 2007
  • In the last 5 years, collisions of fishing vessels have recorded about 54.6% of the total marine accidents. Specially about 64.0% of these collisions were caused by navigator's negligence of watch keeping during works. The purpose of this paper is to develop vessel detecting system that is able to receive the whistle blast of other vessel and make a warning sound and light when the fishermen can not confirm the approaching another vessel on account of fishing works. It is designed to receive the whistle signal blast by a weather tight microphone. The signal is processed by analog active filter in order to enhance the SNR(Signal to noise ratio). And this microprocessor-based system is programmed to do ADC(Analog to digital converting), FFT analysis, controls of warning sound and light.

Determination of Tool Orientation in 5-axis Milling Using Potential Energy Method (포텐셜 에너지를 이용한 5축 NC 밀링의 공구방향 결정)

  • 조인행;이건우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1994.10a
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    • pp.199-204
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    • 1994
  • A method for determining the collision-free tool orientation for 5-axis milling is presented. In 5-axis milling, the proper tool orientation as well as the optimal CC-data has to be selected to machine the workpiece efficiently and accurately and accurately. Essentially, the tool orientation should be determined to avoid collisions between the tool and workpiece and to enable efficient machining. In this work, the tool orientation is determined at every CC-point which is assumed to be given. The procedure uses the potential energy method that assumes the tool and the part surfaces are charged with static electricity. This approach can detect can deteat both global and local collisions (gouging) irrespective of the tool shape. Further, in order to increase the machining efficiency, the material removal rate is maximized simultaneously.

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A Comparative study On 2D Collision Detection Algorithms For Computer Games (컴퓨터게임을 위한 2D 충돌 감지 알고리즘 비교 분석에 관한 연구)

  • Lee, Young-Jae
    • Journal of Korea Game Society
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    • v.1 no.1
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    • pp.42-48
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    • 2001
  • Collision is a brief dynamic event consisting of the close approach of two or more objects or particles resulting in an abrupt change of momentum or exchange of energy because of interaction. Collisions play very important role in computer graphics, computer games and animations fields. Collisions can supply active interaction between cyberspace and real world and give much interests for making nice games so reasonable collision detection algorithms are needed. Collision detection algorithms should satisfy being fast and accuracy. In this paper, we survey the 2D collision detection algorithms between geometric models. We present several methods and system available for collision detection.

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A Study on the Comparison for the Child Occupant Safety from Frontal Crash Test Protocol (정면충돌 시험방법에 따른 어린이 탑승객 충돌안전성 비교연구)

  • Kim, Siwoo
    • Journal of Auto-vehicle Safety Association
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    • v.8 no.3
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    • pp.33-38
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    • 2016
  • Recently, development in vehicle safety could increase interest in children's safety in vehicle collisions. But the research of children safety in vehicle collisions is not being conducted as many as that of adult's. Especially the study for the vehicle crash was not much. This study focused on the comparison of child safety between test protocols to evaluate children's safety in crash test. Injuries of Q6 and Q10 dummy were evaluated using FFRB (Full frontal rigid barrier) test and 40% ODB (Offset deformable barrier) test with one model vehicle. Even though the limit number of test, the tendency of injury criteria of Q6 and Q10 dummy between the test protocols was not conformed but injury criteria of Q6 and Q10 were not same between FFRB and 40% ODB.