• Title/Summary/Keyword: cones

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An Empirical Study on Development of Traffic Safety Facilities for Safe Autonomous Vehicle Operation in Construction Areas (자율주행자동차의 공사구간 안전주행 지원을 위한 교통안전시설물 개발 실증 연구)

  • Jiyoon Kim;Jisoo Kim
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.22 no.5
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    • pp.163-181
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    • 2023
  • Improving the detection performance of facilities corresponding to the sensors of autonomous vehicles helps driving safety. In the road and transportation field, research is being conducted to improve the detection performance of sensors by road infrastructure or facilities. As part of this on the development of autonomous driving support infrastructure, the shape of traffic cones and drums to ensure sufficient LiDAR detection performance even rainy conditions and maintain the line-of-sight guidance function in construction zones improvement effect. The principle was to increase reflection performance and ensure no significant difference in shape from existing facilities. Traffic cones were manufactured in square pyramid shapes instead of cones, and drums were manufactured in hexagonal and octagonal pillar shapes instead of cylinders. LiDAR detection data for the facility was confirmed on a clear day and with 20 mm/h and 40 mm/h rainfall. The detection performance of the square pyramid-shaped traffic cone and octagonal column-shaped drum was to the existing facility. On the other hand, deviations occurred due to repeated measurements, and significance could not be confirmed through statistical analysis. By reflecting these results, future studies will seek a form in which data can be obtained uniformly despite the diversity of measurement environments.

ALTERNATIVE PROOF OF EXISTENCE THEOREM FOR CERTAIN COMPETITION MODELS

  • Ahn, Inkyung
    • Journal of the Chungcheong Mathematical Society
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    • v.13 no.1
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    • pp.119-130
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    • 2000
  • We give alternative proof of the existence theorem for certain elliptic systems describing competing interactions with nonlinear di usion. The existence of positive solution depends on the sign of the principal eigenvalue of suitable operators of Schr$\ddot{o}$dinger type. If the sign of such operators are both positive, then system has a positive solution. The main tool employed is the fixed point index of compact operator on positive cones.

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A Lower Upper - bound Solutions for Shear Spinnings of Cones (원추체의 전단스피닝 가공에 대한 상계해석)

  • 최재찬
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.6 no.2
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    • pp.169-175
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    • 1982
  • 원주체의 전단스피닝 가공에서 가공물의 반경과 두께 방향의 상대 위치가 변화하지 않는다는 조건 아래서 흐름 함수에 의하여 속도장을 구하고, 접촉계수에 대하여 변형에너지의 국소치를 구함으로써 상당히 낮은 상계치를 얻었으며, 이를 A1-1100-1, A1-1100-H14, A1-6061-0 등 여러 가지 재료에 대한 실험치와 비교한 결과, 정량적으로 일치하였다.

SHAPE OPERATOR AND GAUSS MAP OF POINTWISE 1-TYPE

  • KIM, DONG-SOO;KIM, YOUNG HO
    • Journal of the Korean Mathematical Society
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    • v.52 no.6
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    • pp.1337-1346
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    • 2015
  • We examine the relationship of the shape operator of a surface of Euclidean 3-space with its Gauss map of pointwise 1-type. Surfaces with constant mean curvature and right circular cones with respect to some properties of the shape operator are characterized when their Gauss map is of pointwise 1-type.

ELLIPTIC SYSTEMS INVOLVING COMPETING INTERACTIONS WITH NONLINEAR DIFFUSIONS II

  • Ahn, In-Kyung
    • Communications of the Korean Mathematical Society
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    • v.12 no.4
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    • pp.869-880
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    • 1997
  • In this paper, we give sufficient conditions of certain elliptic systems involving competing iteractions with nonlinear diffusion rates. The existence of positive solution depends on the sign of the first eigenvalue of operators of Schr$\ddot{o}$dinger type. More precisely, if the sign of such operators are either both positive or both negative, then system has a positive solution. The main tool employed is the fixed point index of compact operator on positive cones.

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A REMARK ON QUASI CONTACT METRIC MANIFOLDS

  • Park, JeongHyeong;Sekigawa, Kouei;Shin, Wonmin
    • Bulletin of the Korean Mathematical Society
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    • v.52 no.3
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    • pp.1027-1034
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    • 2015
  • As a natural generalization of the contact metric manifolds, Kim, Park and Sekigawa discussed quasi contact metric manifolds based on the geometry of the corresponding quasi $K{\ddot{a}}hler$ cones. In this paper, we show that a quasi contact metric manifold is a contact manifold.

EXISTENCE OF n POSITIVE SOLUTIONS TO SECOND-ORDER MULTI-POINT BOUNDARY VALUE PROBLEM AT RESONANCE

  • Wang, Feng;Zhang, Fang
    • Bulletin of the Korean Mathematical Society
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    • v.49 no.4
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    • pp.815-827
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    • 2012
  • The existence of $n$ positive solutions is established for second order multi-point boundary value problem at resonance where $n$ is an arbitrary natural number. The proof is based on a theory of fixed point index for A-proper semilinear operators defined on cones due to Cremins.

INFINITE FLOCKS OF QUADRATIC CONES-II GENERALIZED FISHER FLOCKS

  • Jha, Vikram;Johnson, Norman L.
    • Journal of the Korean Mathematical Society
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    • v.39 no.4
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    • pp.653-664
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    • 2002
  • This article discusses a new representation of the generalized Fisher flocks and shows that there is a unique flock for each full field K of odd or zero characteristic that has a full field quadratic extension. It is also shown that partial flock extensions of 'critical linear subflocks'are completely determined.

EXISTENCE OF MULTIPLE POSITIVE SOLUTIONS FOR THE SYSTEMS OF HIGHER ORDER BOUNDARY VALUE PROBLEMS ON TIME SCALES

  • Rao, A. Kameswara
    • Journal of applied mathematics & informatics
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    • v.33 no.1_2
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    • pp.1-12
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    • 2015
  • This paper is concerned with boundary value problems for systems of n-th order dynamic equations on time scales. Under the suitable conditions, the existence and multiplicity of positive solutions are established by using abstract fixed-point theorems.