• 제목/요약/키워드: Geometric Characteristics

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도로 선형특성에 따른 럼블스트립의 교통사고 감소효과 (Accident Reduction Effect of Rumble Strips by Highway Geometric Characteristics)

  • 오흥운
    • 대한토목학회논문집
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    • 제30권3D호
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    • pp.289-294
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    • 2010
  • 럽블스트립은 교통사고 감소에 기여를 하는 것으로 국내외 논문을 통해 잘 알려져 있다. 본 논문은 도로의 기하구조와 럼블스트립의 설치효과 관계에 대하여 교통사고 감소통계를 이용하여 분석하였다. 고속도로 구간에서 럼블스트립 설치전후의 교통사고 통계를 비교하였고 럼블스트립 설치지점의 평면선형, 종단선형, 설치길이와 비교하였다. 분석결과, 종단선형이 하향(-)인 구간에서 럼블스트립 설치효과가 높은 것으로 나타났다. 평면선형상에서 우곡선구간에서 효과적임을 알 수 있었다. 또한 설치길이 면에서 상대적으로 설치길이가 작아도 교통사고 감소의 유의성이 높은 것으로 나타났다.

사용자 의도에 의한 삼차원 삼각형 메쉬의 기하적 특징 추출 (User-Steered Extraction of Geometric Features for 3D Triangular Meshes)

  • 유관희;하종성
    • 한국컴퓨터그래픽스학회논문지
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    • 제9권2호
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    • pp.11-18
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    • 2003
  • 본 논문은 2차원 영상에서 커서를 특징 경계로 이동시키는 스내핑(snapping)과 특징 경계를 추출하는 래핑(wrapping)을 3차원 메쉬로 확장하여 메쉬상의 기하적 특징을 사용자가 의도한 대로 추출할 수 있는 기법을 다룬다. 먼저 메쉬상의 나타나는 기하적 특징을 계량화하기 위해 근사 곡률과 움직임 비용함수를 정의한다. 이들 수치 값을 기반으로 기하적 스내핑과 기하적 래핑 알고리즘을 설계한다. 본 논문에서는 제안한 알고리즘을 얼굴 메쉬와 치아 메쉬상에 나타나는 기하적 특징을 추출하기 위해 적용하였다.

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메타버스에서의 미래주의 패션 조형성 - DRESSX 가상패션 플랫폼을 중심으로 - (Formative Characteristics of Futurism Fashion in Metaverse - Focusing on DRESSX the virtual fashion platform -)

  • 양루이;손수민
    • 한국의상디자인학회지
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    • 제25권2호
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    • pp.135-150
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    • 2023
  • The purpose of this study is to understand the formative characteristics of futuristic virtual fashion revealed in virtual fashion platforms targeting the human body. First, the current status of fashion in the metaverse and futurist fashion were reviewed and summarized by referring to prior research. Next, among the items posted on DRESSX, "futurism" was searched and those resturning a positive result were collected as research subjects. The characteristics were organized into design elements: colors, shapes, materials, and patterns. Futuristic aesthetic characteristics were derived from the characteristics of each design element. As a result, color showed the characteristics of achromatic, vivid and neon colors, multi-color and gradation, multi-color due to reflected light, and color conversion. As for the form, a body-concious look or exaggerated silhouettes, spatial expressions in geometric structures, forms imitating living things, and fluid silhouettes using clouds were prominent. Materials showed the digitization of universal clothing materials, application of industrial materials, use of metal materials, and unrealistic materials. In the patterns, geometric abstract patterns, patterns that reveal the digital world view, and moving fluid patterns appeared. The aesthetic characteristics of futurism in virtual fashion were revealed in four categories: visual dynamics, high-tech sensibility, variability, kineticisim. Visual dynamics were revealed in geometric forms, and intense neon colors. High-tech sensibility was prominent in the use of metal and industrial materials, light emission, and patterns of the digital world view. The expression of multiple colors by reflected light and the change showed the variability of futurism. The use of unrealistic materials, such as clouds and fire and fluid silhouettes expressed kineticisim. The infinite expressiveness of virtual fashion made it possible to actively express the aesthetic characteristics of futurism.

고속도로 주행속도 변화에 영향을 미치는 도로기하구조 특성분석 : 제한속도 상향전후 비교를 중심으로 (Characteristics of Geometric Conditions Affecting Freeway Travel Speed : Focused on Speed Limit Change)

  • 홍성민;오철
    • 한국도로학회논문집
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    • 제16권5호
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    • pp.83-90
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    • 2014
  • PURPOSES : The purpose of this study is to identify the factors affecting the effectiveness of speed limit change that is defined as the amount of increased travel speed. METHODS : A ordered logit model was adopted to analyze the relationship between the change in travel speed and contributing factors. A stretch of Kyungbu freeway was selected for the analysis because the Korea expressway corporation has raised speed limit from 100km/h to 110km/h since September 1st in 2010. RESULTS : The results showed that geometric design elements, speeding cameras, and section length were identified as factors contributing the effectiveness. Contributing geometric design elements include the number of horizontal curves and vertical curves that do not meet the design requirement with 110km/h speed limit. CONCLUSIONS : The outcome of this study will be used for establishing various traffic operations and control strategies for freeway speed management.

평직 및 주자직 복합재료의 탄성계수 예측 (Prediction of engineering constants for plain and 8-hardness satin woven composites)

  • 변준형
    • 대한기계학회논문집A
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    • 제21권11호
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    • pp.1757-1764
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    • 1997
  • The geometric and elastic models based on the unit cell have been proposed to predict the geometric characteristics and the engineering constants of plain and satin woven composites. In the geometric model, length and inclined angle of the yarn crimp and the fiber volume fraction of woven composites have been predicted. In the elastic model, the coordinate transformation has been utilized to transform the elastic constants of the yarn crimp to those of woven composites, and the effective elastic constants have been determined from the volume averaging of the constituent materials. Good correlations between the model predictions and the experimental results of carbon/epoxy and glass/epoxy woven composites have been observed. Based on the model, the effect of various geometric parameters and materials on the three-dimensional elastic properties of woven composites can be identified.

휠 세트 Yaw 운동을 고려한 바퀴와 선로 사이의 3차원 접촉 기하 해석 (Analysis of 3-dimensional Wheel/Rail Contact Geometry Considering Wheelset Yaw Motion)

  • 김도중;박삼진
    • 한국기계연구소 소보
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    • 통권15호
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    • pp.5-17
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    • 1985
  • Dynamics of railway vehicles are strongly influenced by the wheel/rail contact forces. Wheel/rail contact geometric characteristics are important parameters to determining wheel/rail contact forces. In general, geometric relations between wheel and rail are represented by nonlinear functions of the wheelset lateral excursion and the relative yaw angle. There are some analytical and experimental studies to show the influences of the wheelset lateral displacement on wheel/rail geometric relations. Recently radial steering bogie which is designed to have flexible yaw motions of wheelsets was developed to improve curve negotiation performance. The radial steering bogie makes it important problem to study the effects of wheelset yaw motion on wheel/rail geometric relations. This paper describes the method to analyze 3-dimensional wheel/rail contact geometry considering wheelset yaw motion and describes also some computer simulation results.

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Design of Augmented Guidance Law Considering Geometric Pursuit Angle

  • Kim, You-Dan;Kim, Ki-Seok;Moon, Gwan-Young
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.125.5-125
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    • 2001
  • Until now, many guidance laws have been developed. They mainly used the classical tail-pursuit guidance method based on geometric angle information, the proportional navigation method based on the line of sight(LOS) rate, and the optimal guidance law based on optimal control theorem. In the augmented guidance law, target acceleration information and autopilot characteristics are added the guidance command. In this study, new guidance laws considering geometric angle are proposed. Two guidance laws are developed for the midcourse guidance law, and a guidance law is developed for the terminal guidance respectively. The proposed guidance laws utilize the LOS rate and the geometric angle information simultaneously. In the midcourse guidance, the guidance command is ...

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차륜/레일 기하학적 인자에 의한 등가답면구배 영향 분석 (Analysis on the Influence of Wheel/Rail Geometric Parameters on the Equivalent/Conicity)

  • 허현무;권성태
    • 한국철도학회논문집
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    • 제8권5호
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    • pp.490-494
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    • 2005
  • The geometric parameters between wheel and rail change wheel/rail contact geometry characteristics, and this influence dynamic behavior of rolling stock. So, the selections of optimum geometric parameters between wheel and rail is important for planning of railway system. In this study, we have analyzed the influence of geometric parameters like wheel flange-back distance, gage, and rail inclination on the equivalent conicity relating to dynamic behavior. The analyses show the following results. The widening of wheel flange-back distanc, the decrement of gage increase the equivalent conicity and the increment of rail inclination show the sharp change of the equivalent conicity.

Analyzing nonlinear mechanical-thermal buckling of imperfect micro-scale beam made of graded graphene reinforced composites

  • Khalaf, Basima Salman;Fenjan, Raad M.;Faleh, Nadhim M.
    • Advances in materials Research
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    • 제8권3호
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    • pp.219-235
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    • 2019
  • This research is devoted to analyzing mechanical-thermal post-buckling behavior of a micro-size beam reinforced with graphene platelets (GPLs) based on geometric imperfection effects. Graphene platelets have three types of dispersion within the structure including uniform-type, linear-type and nonlinear-type. The micro-size beam is considered to be perfect (ideal) or imperfect. Buckling mode shape of the micro-size beam has been assumed as geometric imperfection. Modified couple stress theory has been used for describing scale-dependent character of the beam having micro dimension. Via an analytical procedure, post-buckling path of the micro-size beam has been derived. It will be demonstrated that nonlinear buckling characteristics of the micro-size beam are dependent on geometric imperfection amplitude, thermal loading, graphene distribution and couple stress effects.

차륜/레일 기하학적 인자의 등가답면구배에 미치는 영향 (A study on the influence of wheel/rail geometric parameters to equivalent conicity)

  • 허현무;권성태;김형진
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 추계학술대회 논문집
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    • pp.430-434
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    • 2004
  • The geometric parameters between wheel and rail change wheel/rail contact geometry characteristics, and this influence dynamic behavior of rolling stock. So, the selections of optimum geometric parameters between wheel and rail is important for planning of railway system. In this study, we have analyzed the influence of geometric parameters like wheel flange-back distance, gage, and rail inclination to the equivalent conicity relating dynamic behavior. The analyses show the following results. The widening of wheel flange-back distance increase the equivalent conicity, the widening of gage, rail inclination 1/20 compared with rail inclination 1/40 decrease the equivalent conicity.

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