• The KIPS Transactions:PartA
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• v.8A no.1
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• pp.42-47
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• 2001

In this paper, we present a curve fitting algorithm using a ball curve. Our algorithm is recursive method for fitting, which is not a traditional ball function but a continuous ball function. This algorithm consists of two steps. The first step, it is classified the composite corner points to joint points until selected from the given data set. The second step is the curve fitting. The basis function for curve fitting is use to ball function. Also, the weighted least square method, to insert knot, is an efficient method for piecewise ball curve and ball curve segments will be smoothly connected at all composit points. The proposed algorithm will be applied to represent image representation, like fonts, digital image and GIS.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.247-259
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• 1998

Analyses which loads were regarded as instant load and gradual step load were performed with data measured on gradually loaded field, and the results were inspected to find effect of load condition, and final settlements predicted by Hyperbolic, Tan's, Asaoka's, and Monden's method were compared with each other. According to above analyses, the following conclusions were obtained. Settlement curves which loads were regarded as instant load and gradual step load were beginning to coincide at time of twice duration of embankment. On the ground installed vertical drain, the result of Hyperbolic, Tan's, Asaoka's, Monden's, curve fitting I, and curve fitting II (simple, Carrillo) methods make conclude that Asaoka, curve fitting I, and curve fitting II methods agree with measured settlement.

• Journal of Information Processing Systems
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• v.4 no.4
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• pp.153-158
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• 2008

This paper deals with the geometric fitting algorithms for parametric curves and surfaces in 2-D/3-D space, which estimate the curve/surface parameters by minimizing the square sum of the shortest distances between the curve/surface and the given points. We identify three algorithmic approaches for solving the nonlinear problem of geometric fitting. As their general implementation we describe a new algorithm for geometric fitting of parametric curves and surfaces. The curve/surface parameters are estimated in terms of form, position, and rotation parameters. We test and evaluate the performances of the algorithms with fitting examples.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.12
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• pp.78-85
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• 1996

The determination of the optimum biarc curve passing through a given set of points along involute curve is studied. The method adopted is that of finding the optimum no. of span and the optimum length of the span such that the error between the biarc curve and involute curve is minimum. Irregular curve span method is effectively used to describe the involute curve with reduced length of NC-Code.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.71-78
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• 1999

The determination of the optimum biarc curve passing through a given set of points along involute curve is studied. The method adopted is that of finding the optimum number of span and the optimum length of the span such that error between the biarc curve and involute curve minimum. Iterative method is effectively used to find the optimim number and length of the span on involute curve with reduced length of NC-code.

• Korean Journal of Computational Design and Engineering
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• v.9 no.3
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• pp.183-191
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• 2004

This paper deals with smooth curve fitting of data corrupt by noise. Most research efforts have been concentrated on employing the smoothness penalty function with the estimation of its optimal parameter in order to avoid the 'overfilling and underfitting' dilemma in noisy data fitting problems. Our approach, called DBSF(Differentiation-Based Smooth Fitting), is different from the above-mentioned method. The main idea is that optimal functions approximately estimating the derivative of noisy curve data are generated first using genetic programming, and then their integral values are evaluated and used to recover the original curve form. To show the effectiveness of this approach, DBSP is demonstrated by presenting two illustrative examples and the application of estimating the principal dimensions of bulk cargo ships in the conceptual design stage.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.338-347
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• 2006

연직차수벽은 오염지역이나 폐기물 매립장에서 오염된 지하수 (때로는 오염된 수증기) 흐름을 차단하거나 또는 오염지역의 정화처리시 효율을 높이기 위하여 외부로부터 지하수 흐름을 막기 위해 설치된다. 이 논문에서는 연직차수벽의 가장 중요한 설계요소인 차수벽체의 현장 투수성을 평가하는 방법들중 가장 보편적으로 사용되는 단공식 순간 변위시험 (slug test)을 소개한다. 연직차수벽에서 실행된 단공식 순간 변위시험 결과를 해석하기 위해서, 연직차수벽의 압축성과 기하학적인 특성을 고려한 수정된 linear curve fitting 방법을 제안하고 그 적용성을 case study를 통해 평가한다. 기존의 대수층 투수계수 산정에 이용된 curve fitting 방법들에 비하여 수정된 linear curve fitting 방법은 보다 정확한 연직차수벽체의 투수성을 평가하도록 한다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.7 s.112
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• pp.769-776
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• 2006

A measured frequency response function can be represented as a ratio of two polynomials. A curve-fitting of frequency responses with Legendre polynomialis suggested in the paper. And the suggested curve-fitting algorithm is based on the least-square error method. Since the Legendre polynomials satisfy the orthogonality condition, the curve-fitting with the polynomials results to more reliable curve-fitting than ordinary polynomial method. Though the proposed curve-fitting with Legendre polynomials cannot cover all frequency range of interest, example shows that the suggested method is quite applicable in a limited frequency band.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42
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• pp.68-77
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• 2000

Analyses, in which load was regarded as instant load and gradual step load, respectively, were performed with data measured on a gradually loaded field, and the results were inspected to find the effect of load conditions, and the final settlements which were predicted by Hyperbolic, Tan's, Asaoka's, and Monden's methods were compared with each other. Settlement curves in which load was regarded as instant load and gradual step load being to coincide at twice the time of duration of embankment. On the ground installed vertical drain, from the results of Hyperbolic, Tan's, Asaoka's, Monden's, Curve fitting I, and Curve fitting II (simple, carrillo) methods it was concluded that Asaoka, Curve fitting I, and Curve fitting II methods are reliable for prediction final settlement with back analysis.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.3
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• pp.283-291
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• 2011

Purpose: To find an empirical fitting curve to represent the relationship between the luminous transmittance and tinted time in tinted lenses using exponential decay curves. Methods: Total ninety tinted lenses were prepared with CR-39 lenses and six different colored dyes. Single, double and triple exponential decay curves were used as trial curves in order to find the empirical fitting curve. Result: The results showed that the best empirical fitting curve was triple exponential decay curves. Conclusions: We propose triple exponential decay curves as proper empirical fitting curves to represent the tinted-time dependence of the luminous transmittance in tinted lenses.