• 한국수자원학회논문집
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• 제32권2호
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• pp.185-195
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• 1999

운동파 이론의 수치해석에는 유한차분법과 특성곡선법이 주로 사용된다. 유한차분법의 경우 지배방정식의 차분과정에서 발생하는 절단오차에 의하여 첨두유량의 감쇠가 발생한다. 특성곡선법의 경우 첨두유량은 양호하게 보존되지만, 수치해석 과정에서 발생하는 충격파를 적절하게 고려하지 못한다. 본 연구에서는 운동파 이론에 근거한 각각의 수차해석 기법의 특성을 살펴보았으며, 특성곡선법으로 수치해석할 때 발생하는 충격파의 수치처리기법인 Propagating Shock Fitting 기법과 Approximate Shock Fitting 기법에 대하여 적용성을 파악하였다. Propagation Shock Fitting 기법은 충격파를 양호하게 처리하였으나 유로연장이 긴 하천에서 유량이 급변하는 경우 적절하게 충격파를 처리하지 못하였다. Propagation Shock Fitting 기법을 반복하여 계산하는 Approximate Shock Fitting 기법은 이러한 경우에 발생하는 충격파를 적절히 처리하는 것을 확인할 수 있었다. 충격파 처리기법에 의한 운동파 이론의 계산결과와 완전동력학파 이론에 의한 결과도 비교하고 토의하였다.

• International Journal of Automotive Technology
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• 제7권7호
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• pp.847-852
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• 2006

A fitting process carried out in the automobile transmission assembly line is classified into three classes; heat fitting, press fitting, and their combined fitting. Heat fitting is a method that applies heat in the outer diameter of a gear to a suitable range under the tempering temperature and assembles the gear and the shaft made larger than the inner radius of the gear. Its stress depends on the yield strength of a gear. Press fitting is a method that generally squeezes gear toward that of a shaft at room temperature by a press. Another method heats warmly gear and safely squeezes it toward that of a shaft. A warm shrink fitting process for an automobile transmission part is now gradually increased, but the parts (shaft/gear) assembled by the process produced dimensional change in both outer diameter and profile of the gear so that it may cause noise and vibration between gears. In order to solve these problems, we need an analysis of a warm shrink fitting process in which design parameters such as contact pressure according to fitting interference between outer diameter of a shaft and inner diameter of a gear, fitting temperature, and profile tolerance of gear are involved. In this study, an closed form equation to predict the contact pressure and fitting load was proposed in order to develop an optimization technique of a warm shrink fitting process and verified its reliability through the experimental results measured in the field and FEM, thermal-structural coupled field analysis. Actual loads measured in the field have a good agreement with the results obtained from theoretical and finite element analysis and also the expanded amounts of the outer diameters of the gears have a good agreement with the results.

• 한국컴퓨터정보학회논문지
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• 제25권3호
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• pp.145-154
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• 2020

본 논문에서는 자전거 피팅을 좀 더 정교하고 신속하게 진행하기 위해 자전거 피팅 소프트웨어와 하드웨어를 통합한 시스템을 개발하기 위한 DB구축을 목표로 포괄적인 자전거 피팅 방법의 표준화가 요구됨에 따라 다수의 임상결과와 실험을 통해 이에 맞는 자전거 피팅 방법을 제안한다. 이 자전거 피팅 방법은 심층상담, 자전거체크, 정교한 신체사이징 및 분석을 통해 라이더를 위한 자전거 세팅 값을 결정할 수 있으며 이 세팅 값으로 조정된 자전거에서 고정 라이딩을 통해 자세와 페달링 토크를 분석하고 이을 통해 가장 효율이 높은 세팅 값을 찾아 자전거를 라이더의 요구에 맞게 최적화 할 수 있는 피팅 방법에 대한 결과를 도출 했다. 이와 같은 피팅 방법은 자전거 라이더의 만족도를 높일 수 있으며 정확한 자전거 세팅 값을 통해 부상예방도 기대할 수 있다.

• 한국정밀공학회지
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• 제23권9호
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• pp.54-60
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• 2006

Fitting process carried out in automobile transmission assembly line is classified into three classes; heat fitting, press fitting, and their combined fitting. Heat fitting is a method that heats gear to a suitable range under the tempering temperature and squeezes it toward the outer diameter of shaft. Its stress depends on the yield strength of gear. Press fitting is a method that generally squeezes gear toward that of shaft at room temperature by press. Another method heats warmly gear and safely squeezes it toward that of shaft. Warm shrink fitting process for automobile transmission part is now gradually increased, but the parts (shaft/gear) assembled by this process produced dimensional changes of gear profile in both radial and circumferential directions. So that it may cause noise and vibration between gears. In order to solve these problems, we need an analysis of warm shrink fitting process, in which design parameters are involved; contact pressure according to fitting interference between outer diameter of shaft and inner diameter of gear, fitting temperature, and profile tolerance of gear. In this study, an closed form equation to predict contact pressure and fitting load was proposed in order to develop optimization technique of warm shrink fitting process and verified its reliability through the experimental results measured in the field and FEM, that is, thermal-structural coupled field analysis. Actual loads measured in the field have a good agreement with the results obtained by theoretical and finite element analysis and also the expanded amounts of the gear profile in both radial and circumferential directions are within the limit tolerances used in the field.

• 한국정밀공학회지
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• 제23권5호
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• pp.37-43
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• 2006

Fitting process carried out in automobile transmission assembly line is classified into three classes; heat fitting, press fitting, and their combined fitting. Heat fitting is a method that heats gear to a suitable range under the tempering temperature and squeezes it toward the outer diameter of shaft. Its stress depends on the yield strength of gear. Press fitting is a method that generally squeezes gear toward that of shaft at room temperature by press. Another method heats warmly gear and safely squeezes it toward that of shaft. Warm shrink fitting process for automobile transmission part is now gradually increased, but the parts (shaft/gear) assembled by this process produced dimensional change in both outer diameter and profile of the gear. So that it may cause noise and vibration between gears. In order to solve these problems, we need an analysis of warm shrink fitting process, in which design parameters are involved; contact pressure according to fitting interference between outer diameter of shaft and inner diameter of gear, fitting temperature, and profile tolerance of gear. In this study, an closed form equation to predict contact pressure and fitting load was proposed in order to develop optimization technique of warm shrink fitting process and verified its reliability through the experimental results measured in the field and FEM, that is, thermal-structural coupled field analysis. Actual loads measured in the field have a good agreement with the results obtained by theoretical and finite element analysis and also the expanded amounts of the outer diameters of the gears have a good agreement with results.

• 한국정밀공학회지
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• 제25권6호
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• pp.47-54
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• 2008

Fitting process carried out in the automobile transmission assembly line is classified into three classes; heat fitting, press fitting, and their combined fitting. Heat fitting is a method that heats gear to a suitable range under the tempering temperature and squeezes it toward the outer diameter of shaft. Its stress depends on the yield strength of gear. Press fitting is a method that generally squeezes gear toward that of shaft at room temperature by a press. Another method heats warmly gear and safely squeezes it toward that of shaft. Warm shrink fitting process for the automobile transmission part is now gradually increased, but the parts (shaft/gear) assembled by this process produced dimensional changes in both the outer diameter and profile of the gear. So that it may cause noise and vibration between gears. In order to solve these problems, we need an analysis of warm shrink fitting process, in which design parameters are involved; contact pressure according to fitting interference between outer diameter of shaft and inner diameter of gear, fitting temperature, and profile tolerance of gear. In this study, an closed form equation to predict contact pressure and fitting load was proposed in order to develop an optimization technique of the warm shrink fitting process and verified its reliability through the experimental results measured in the field and FEM, that is, thermal-structural coupled field analysis. Actual loads measured in the field was in good agreements with the results obtained by the theoretical and finite element analysis.

• 한국의상디자인학회지
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• 제26권2호
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• pp.33-43
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• 2024

This study comprehensively analyzes previous research comparing the similarities between 3D virtual and actual fittings, and identifies the current usage and limitations of virtual fitting programs. The findings reveal that, in most cases, 3D virtual fittings are not perfect substitutes for actual fittings. To address these limitations, this research focuses on the Hohenstein fitting test and BP-ANNs-based garment fit evaluation method, which incorporate various parameters, such as the correlation between wearers and garments, garment pressure, and ease, thus providing objective data, such as data acquired that can enhance subjective evaluations. By integrating such objective assessments, the study suggests potential improvements in virtual fitting accuracy. This research is expected to provide foundational data necessary for the development of a consumer virtual fitting systems alongside advancements in 3D virtual fitting technology.

• 정보처리학회논문지A
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• 제8A권1호
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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.

• 분석과학
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• 제8권1호
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• pp.41-45
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• 1995

혼합된 희토류 원소의 농도를 정량적으로 분석하기 위하여 형광신호를 비선형 fitting하는 방법을 사용하였다. 본 연구에서는 Sm과 Eu 두 희토류 원소의 혼합된 형광을 비선형 fitting법으로 분리하여 그 농도를 분석하였다. 분석결과 감도면에서 한 가지 시료만 존재할 경우와 같은 정도인 sub-ppb의 검출한계를 나타냈으며, 혼합물에서 비선형 fitting법에 의해 얻어진 각 원소의 형광수명은 단일 원소만 존재하는 경우와 동일한 결과를 나타냄을 알 수 있었다.

• 한국컴퓨터정보학회논문지
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• 제24권3호
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• pp.123-133
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• 2019

Bicycle fitting used to depend on empirical adherence of bicycle Peter and intuitive judgment by hand, but recent developments in industry and the Fourth Industrial Revolution have continuously developed other related tools that can be applied to bicycle fitting. Depending on these circumstances, bicycle fitting technology is also developing, and due to the difficulty of the technicians, there is a limit to popularizing. The Bicycle Integrated Fitting System has the need for this study to make these problems easy for anyone to operate by the system of manual. The purpose of this study is to examine the methods of physical sizing among the various stages of developing these systems. Accurate physical measurements can improve the efficiency of bicycle riding and minimize the injury of bicycle risers issued by incorrect fittings. Thus, in this study, physical measurement methods for bicycle fitting were derived by body region and applied to the post-measurement fitting as well as the location and method of measurement. It has prepared a basis for establishing a core database for physical measurement of development of integrated bicycle fitting system. Research was conducted to enhance understanding and utilization of users after system development and results were derived for the purpose of the study. Research was conducted to establish a database for the development of a bicycle integrated fitting system, and future research on bicycle fitting methods, application of the system, and hardware development should be carried out.