• Title/Summary/Keyword: Curve

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Procedure of drawing fragility curve as a function of material parameters

  • Kim, Jang-Ho;Li, Jing;Park, Jeong-Ho;Hong, Jong-Seok
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.334-337
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    • 2006
  • Generally, fragility curve has been used in predicting failure of structures due to seismic actions. In this research, the method of drawing fragility curve has been applied to evaluating success/failure of structures and satisfactory/unsatisfactory of concrete mixture performance based on material parameters. In the paper, a detailed explanation of the procedure of drawing fragility curve based on material parameter has been introduced. Fragility curve generating procedure includes generation of virtual data points from limited number of actual data points by bell curve implementation, determination of success/failure status of each data point by assigned criterion, and completion of final fragility curve. For practical applications, workability of concrete mixture content based on "unit water" has been used to obtain fragility curve. Detailed explanation of fragility curve drawing procedure for material parameters is presented.

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Simulation of Stage-Storage Curve Function in Irrigation Reservoirs (저수지 내용적 곡선의 모의발생)

  • 김현영;윤인택;최용선;오수훈
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.37 no.5
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    • pp.73-80
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    • 1995
  • The uses of stage-storage curve function are diverse in irrigation reservoirs. The curve functions would be used to determine the optimal size of spillway length and the inundation area above full water level based on the flood routing in reservoirs. In addition, the curve function would he used to transform the stage to the storage for the reservoir water management, in which the storage is the supply water. Besides those, the curve is necessary for the planning of dredging, the estimation of the effective and the dead storage, the drought management by reservoir, etc. The curve function data, however, are almost unavailable for these purposes. According to the statistics, about 74% of the 2, 900 resevoirs which are maintained by Farm Land Improvement Association have no more effective data. Therefore, the simulation of the curve function could be better alternative. The curve functions were simulated derivating the regression equations based on the basin relief ratio and the effective depth. The results of the verification show the enough reliability of the application to generate the curve function in some reservoirs which do not have the surveyed stage-storage data. Also, even though the averaged curve function would be applicated without the basin relief ratio data, the result shows that the simulated curve is closer to the real one than the linear function by only the existing effective storage data.

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Analysis of Running Safety and Ride Comfort According to the Shape of Transition Curve (완화곡선형상별 차량주행안전성 및 승차감 분석)

  • Choi, Il-Yoon;Um, Ju-Hwan;Kim, Man-Cheol;Park, Chan-Kyoung
    • Journal of the Korean Society for Railway
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    • v.13 no.5
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    • pp.509-515
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    • 2010
  • Primary function of a transition curve is to accomplish gradual transition from the straight to circular curve, so that curvature changes from zero to a finite value. The transition curve enhances the running safety and ride comfort of the vehicle in curve. There are a couple of transition curve such as clothoid, cubic parabola and cosinusoidal curve, etc. In this study, running behaviors of cubic parabola and cosinusoidal curve were investigated and compared by numerical analysis result using VAMPIRE program. Ride comforts for an individual transition curve were evaluated for each transition curve and running behavior and safety were also evaluated to compare the capacity of transition curves.

Analysis of Visual Distortion and Suggestion of Design Criteria at Curve Sections (곡선부 시각왜곡현상 분석 및 설계기법 제시)

  • Ha, Tae-Jun;Jeong, Jun-Hwa;Lee, Jeong-Hwan;Lee, Suk-Ki
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.6D
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    • pp.663-673
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    • 2009
  • Driver's perceived curve radius is different from actual curve radius at curve sections. This is called visual distortion. It has effect on operation speed according to driver's perception and finally bad effect on safety at curve sections. At present, however, there is no research on quantitatively analysis of visual distortion and no criteria for curve section design considering the visual distortion. Therefore, this study focus on finding degree of visual distortion and suggesting design criteria by visual distortion analysis. The process of this study is as below; First, a calculaiton model of perceived curve radius was developed by survey using computer simulation. In this model, a dependent variable is perceived curve radius and an independent variable is geometric factors. Second, degree of visual distortion was calculated from ratio of perceived curve radius to actual curve radius. Finally, design criteria were suggested through influencing factor analysis of visual distortion at curve sections.

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Changes in Curve-Angle of Blade during Salting of Chinese Cabbage (배추의 소금절임중 엽신의 휘임도 변화)

  • Kim, Mi-Gyeong;Kim, Il-Du;Kim, Sun-Dong
    • Korean Journal of Food Preservation
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    • v.4 no.2
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    • pp.163-171
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    • 1997
  • This study was undertaken to investigate changes m curve angle of Chinese cabbage blade during salting at various concentration(10, 15, 20, 25%) of salt to evaluated salting degree by curve angle during salting at 20$^{\circ}C$. Salt concentration of brine, the amount of water elution, salt penetration of the tissue(salt concentration of Chinese cabbage), weight loss and texture were investigated. Correlation relation between the above factors and curve angle were determined. The curve angles by method of holding the edge of the Chinese cabbage blade was measured. The curve angles of the mesophyll were proportional to salting time and salt concentration, but slope of line equation showed higher than that of mid-rib. The ideal method of salting evaluation by curve angle was MCA-MRC (the measuring curve angle of mid-rib C) at each concentration of salt. The results of curve angle when reached 3% salt of Chinese cabbage tissue calculated by MCA-MRC at 10, 15, 20 and 25% salting were 57$^{\circ}$, 43$^{\circ}$, 36$^{\circ}$, and 33$^{\circ}$, respectively. And salting times calculated by the same conditions were 19, 12.5, 9.1 and 4.4hours, respectively.

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A study on Auto-drawing for Involute Curve and Trochoidal fillet curve (인벌류트 커브와 트로코이드 필렛 커브의 자동생성에 관한 연구)

  • Kim, M.J.;Prak, J.H.;Kim, T.H.;Lee, S.S.;Jeon, E.C.
    • Proceedings of the KSME Conference
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    • pp.834-840
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    • 2001
  • Gear is general mechanical elements that used for power transmission between two shafts that interval is comparatively short. and it delivers big power as accurate ratio of speed. The profile of Spur gear which is the most basic factor is divided into Trochoidal fillet curve and Involute curve. Involute curve is used a lot of a shaped curve of machine parts such as a gear, a scroll compressor and a collar of centrifugal pump. However, It is poor to study the modeling of Trochoidal fillet curve and the three dimensions model shaped mathematical curve. This paper describes a mathematical model of profile shifted involute gear. and this model is based on Camus's theory. We draw three dimensions gear have accurate mathematical function using ADS, VisualLISP. and To check accuracy and perfection, we make a program of checking Interference. and use for this study.

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A Study on the detection of curve lane using Cubic Spline (Cubic Spline 곡선을 이용한 곡선 차선 인식에 관한 연구)

  • Kang, Sung-Hak;Cheong, Cha-Keon
    • Proceedings of the KIEE Conference
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    • pp.169-171
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    • 2004
  • This paper propose a new detection method of curve lane using Catmull-Rom spline for recognition various shape of the curve lane. To improve the accracy of lane detection, binarization and thinning process are firstly performed on the input image. Next, features on the curve lane such as curvature and orientation are extracted, and the control points of Catmull-Rom spline are detected to recognize the curve lane. Finally, Computer simulation results are given using a natural test image to show the efficiency of the proposed scheme.

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Precision Determination of Anisotropy Constant $K_1$from Magnetization Curve of Partially Aligned Unaxial Anisotropy System

  • Kim, Yoon-Bae;Kim, Hyoung-Tae
    • Journal of Magnetics
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    • v.6 no.4
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    • pp.142-144
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    • 2001
  • A method to deduce the rotational magnetization curve from experimental magnetization of partially aligned uniaxial anisotropy system has been investigated. The curve obtained by this process has been evaluated quire close to the theoretical magnetization curve compared to that obtained by linear extrapolation from high field data. This new approach offers better accuracy for the determination of magnetic anisotropy by fitting a calculated magnetization curve to the obversed one.

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APPLICATION OF DEGREE REDUCTION OF POLYNOMIAL BEZIER CURVES TO RATIONAL CASE

  • PARK YUNBEOM;LEE NAMYONG
    • Journal of applied mathematics & informatics
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    • v.18 no.1_2
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    • pp.159-169
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    • 2005
  • An algorithmic approach to degree reduction of rational Bezier curves is presented. The algorithms are based on the degree reduction of polynomial Bezier curves. The method is introduced with the following steps: (a) convert the rational Bezier curve to polynomial Bezier curve by using homogenous coordinates, (b) reduce the degree of polynomial Bezier curve, (c) determine weights of degree reduced curve, (d) convert the Bezier curve obtained through step (b) to rational Bezier curve with weights in step (c).

J-R Curve Characterization by Load Ratio Analysis and Unloading Compliance Method for SA508 C-3 steel (SA508-3재의 제하컴플라이언스법과 하중비해석을 이용한 파괴저항곡선 평가)

  • 임만배;차귀준;윤한기;안원기
    • Journal of Ocean Engineering and Technology
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    • v.12 no.1
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    • pp.65-75
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    • 1998
  • The fracture resistance curve is one of most important and design techniques employed in nuclear pressure vessel structures. This study is to evaluate the J-R curve characteristics for the SA508C-3 by the unloading compliance method and load rato analysis. The effect of strain aging for the exponential correlation of the J-R curve in this metal are investigated at room temperature, 20$0^{\circ}C$ and 30$0^{\circ}C$. The load ratio analysis method can evaluate the J-R curve by using the simple tension load-displacement curve only without the repeat of the unloading and loading. Therefore, the analysis by the proposed load ratio method has a merit, in comparison with the unloading compliance method, which can measure the crack length without the precision measurement equipment.

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