• Proceedings of the KSR Conference
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• 2003.05a
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• pp.724-729
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• 2003

The prototype of Korean high speed train (KHST), composed of two power cars, two motorized cars and three trailer cars, has been designed, fabricated and tested by the domestic researchers. In this paper, the body vibration has been reviewed from the viewpoint of the vehicle's safety and the vibration limits for components and sub-assemblies mounted on the car-body using by the experimental method. The on-line test of KHST has been carried out up to 260 km/h in the KTX line and proved that KHST has no problems in the vehicle's safety and the vibration limits at this speed. And the characteristics of body vibrations has been predicted at 300 km/h and 350 km/h by fitting curve about the measured acceleration signals.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.7
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• pp.539-547
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• 2003

The prototype of Korean high speed train(KHST), composed of two power cars, two motorized cais and three trailer cars, has been designed, fabricated and tested. In this paper. the body vibration has been reviewed from the viewpoint of the vehicle's safety, the ride comfort and the vibration limits for components and sub-assemblies mounted on the car-body using by analytical method and experimental method. The on-line test of KHST has been tarried out up to 260 ㎞/h in the KTX line and the results of the on-line test show that KHST has no problems in the vehicle's safety. the comfort ride and the vibration limits at this speed. And the characteristics of body vibrations has been Predicted at 300 ㎞/h and 350 ㎞/h by fitting curve about the measured acceleration signals.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.6
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• pp.821-832
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• 2002

The purpose of this study was to develop grading method of the basic brassiere patterns therewith, provide for 12 size's brassiere patterns and prove fitness of their's and shape. The collected data were statistically processed using the SAS 6.12 for Means, Standard Deviation, etc. The results of this study can be summarized as follows; 1. The basic sizes adopted at the first design stage (see fig.1-2) were 75AA, 75A and 75B each of which was designed as upper foundation basic pattern in reference to the cup size. At the second stage, each of the upper body foundation basic pattern was used to design lower cup, upper up, front panel and wing in their order(see fig.3-6). At the third stage, the other sizes were graded in reference to the three brassiere patterns (75AA, 75A and 75B) to produce 12 brassiere sizes(see Tab. 7-8). In order to develop the basic patterns of adult women's brassieres, 33 women were selected per 11 size combination(3 women per size combination), and then, their brassiere fitting was teated. As a result, the fronts of the basic patterns were found to have such problems as undone front center, poor levelling of upper cup's bottom line or lower cup's top line, poor shape of upper cup's outside top line and shoulder strip position. On the other hand, on the rear side of the basic patterns, the central part of the wing was slightly lifted, while the wing width and straps'interval did not befit the ful1-cup brassiere. The result of this first brassiere fitting test showed that the functionality and aesthetics of the basic pattern brassieres were more or less satisfactory, and thus, the problems were addressed for the second teat. In the second test, the aesthetics, breast-shaping effect and functionality of the basic pattern brassieres were much improved. 2. We were to present the final brassiere sizing system to extend the interior length of breast and the exterior length of breast on the basis of fitting test. Thereby, 75B$.$80A$.$80B$.$85A$.$85B's the interior lengths of breast were enlarged to 0.7cm, the rest size was enlarged to 0.5cm and the exterior length of breast was enlarged to 0.5cm regardless of sizes. 3. The upper foundation basic patterns of 75AA and 75B were presented and and the basic brassiere pattern and grading pattern were presented through to.

• Journal of Electrical Engineering and Technology
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• v.13 no.6
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• pp.2530-2544
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• 2018

In this paper, we propose an enhanced LiDAR-camera calibration method that extracts the marker plane from 3D point cloud information. In previous work, we estimated the straight line of each board to obtain the vertex. However, the errors in the point information in relation to the z axis were not considered. These errors are caused by the effects of user selection on the board border. Because of the nature of LiDAR, the point information is separated in the horizontal direction, causing the approximated model of the straight line to be erroneous. In the proposed work, we obtain each vertex by estimating a rectangle from a plane rather than obtaining a point from each straight line in order to obtain a vertex more precisely than the previous study. The advantage of using planes is that it is easier to select the area, and the most point information on the board is available. We demonstrated through experiments that the proposed method could be used to obtain more accurate results compared to the performance of the previous method.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.851_852
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• 2009

Shrink fitting which is assembling process to fix stator core on the motor frame is widely used at the mass production line of motors because of cost and productivity. This process produces compressive stress on a stator core, which causes negative effect for example, core and copper losses on motor performance. Magnetic properties of electrical steel are effected by both compressive and tensile and thermal stresses. Electromagnetic field analysis is considered one of the effective process since one can predict motor performance including core loss precisely. This method can consider non linear magnetic property with magnetic saturation which is typical electrical steel behavior. However this method is strongly depended on non linear magnetic data, one may have different calculation result whether considering mechanical stress or not. This study describes magnetic field analysis of a motor considering mechanical stress from shrink fitting. Analysis results are compared with each stress-free and stressed condition.

• Korean Journal of Remote Sensing
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• v.32 no.1
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• pp.49-60
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• 2016

This paper presents a set of methods to evaluate the image quality of smartphone cameras as compared with that of a DSLR camera. In recent years, smartphone cameras have been used broadly for many purposes. As the performance of smartphone cameras has been enhanced considerably, they can be considered to be used for precise mapping instead of metric cameras. To evaluate the possibility, we tested the quality of one DSLR camera and 3 smartphone cameras. In the first step, we compare the amount of lens distortions inherent in each camera using camera calibration sheet images. Then, we acquired target sheet images, extracted reference lines from them and evaluated the geometric quality of smartphone cameras based on the amount of errors occurring in fitting a straight line to observed points. In addition, we present a method to evaluate the radiometric quality of the images taken by each camera based on planar fitting errors. Also, we propose a method to quantify the geometric quality of the selected camera using edge displacements observed in target sheet images. The experimental results show that the geometric and radiometric qualities of smartphone cameras are comparable to those of a DSLR camera except lens distortion parameters.

• Journal of Fashion Business
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• v.26 no.3
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• pp.116-137
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• 2022

The purpose of this study was to develop jacket patterns that could fit well for women in their 20s with turtle neck syndrome body shape and to present a pattern drafting method. As a research method, an educational pattern was chosen through a preliminary experiment. Fit problems of the educational pattern were derived by wearing it on a virtual model with a turtle neck syndrome body type for each neck angle. Based on the three types of experimental patterns developed by supplementing these problems, a development pattern drafting method was developed for each neck angle. Three development patterns were compared and evaluated with the educational pattern using 3D virtual fitting. Fit problems of the educational pattern included: 1) insufficient ease amounts for hip, hem, bicep, elbow, and sleeve hem circumference; 2) horizontal items could not be leveled due to insufficient back length; 3) the shoulder line went backwards; and 4) the front center line did not form a vertical line. To solve these problems, an experimental pattern was developed by increasing the insufficient ease amount, increasing the insufficient back length, and correcting the position of the shoulder line. Measurements that differed in the pattern drafting method of the three types of development patterns by neck angle were positions of back center line and back neck point, front length, and front neck width. Through appearance evaluation of the development pattern and educational pattern by neck angle, the development pattern was highly evaluated, indicating that problems of the educational pattern were improved.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.2
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• pp.643-661
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• 2018

This paper proposes a novel algorithm for lane detection based on inverse perspective transformation and Kalman filter. A simple inverse perspective transformation method is presented to remove perspective effects and generate a top-view image. This method does not need to obtain the internal and external parameters of the camera. The Gaussian kernel function is used to convolute the image to highlight the lane lines, and then an iterative threshold method is used to segment the image. A searching method is applied in the top-view image obtained from the inverse perspective transformation to determine the lane points and their positions. Combining with feature voting mechanism, the detected lane points are fitted as a straight line. Kalman filter is then applied to optimize and track the lane lines and improve the detection robustness. The experimental results show that the proposed method works well in various road conditions and meet the real-time requirements.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.4
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• pp.159-165
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• 1987

This study proposes an operational method of typhoon risk assessments in Korea, using Statistical analysis and probabilistic description of typhoon at a site. Two alternative simulation and fitting methods are discussed to predict the probabilistic typhoon wind speeds by indirect methods. A Commonly used indirect method is Russell's procedure, which generates about 1,000 Simulation data for typhoon winds, statistically evaluate the base-line distribution, and then fits the results to the Weibull distribution based on probabilistic description of climatological Characteristics and Wind field model of typhoon at a site. However, an alternative procedure proposed in this Paper simulates extreme typhoon wind data of about 150~200 years and directly fits the generated data to the Weibull distribution. The computational results show that the proposed simulation method is more economical and reasonable for typhoon risk-assessment based on the indirect method. And using the proposed indirect method, the probabilistic design wind speed for transmission towers in typhoon-prone region along the South-Western coast is investigated.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.3
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• pp.259-266
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• 2013

An automated cell tracking system is used to automatically analyze and track the changes in cell behavior in time-lapse cell images acquired using a microscope with a cell culture. Clustering is the partial overlapping of neighboring cells in the process of cell change. Separating clusters into individual cells is very important for cell tracking. In this study, we proposed an algorithm for separating clusters by using ellipse fitting based on a direct least square method. We extracted the contours of clusters, divided them into line segments, and then produced their fitted ellipses using a direct least square method for each line segment. All of the fitted ellipses could be used to separate their corresponding clusters. In experiments, our algorithm separated clusters with average precisions of 91% for two overlapping cells, 84% for three overlapping cells, and about 73% for four overlapping cells.