• Journal of Information Processing Systems
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• v.13 no.3
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• pp.491-499
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• 2017

In this study, we proposed a new approach to segment ground and nonground points gained from a 3D laser range sensor. The primary aim of this research was to provide a fast and effective method for ground segmentation. In each frame, we divide the point cloud into small groups. All threshold points and start-ground points in each group are then analyzed. To determine threshold points we depend on three features: gradient, lost threshold points, and abnormalities in the distance between the sensor and a particular threshold point. After a threshold point is determined, a start-ground point is then identified by considering the height difference between two consecutive points. All points from a start-ground point to the next threshold point are ground points. Other points are nonground. This process is then repeated until all points are labelled.

• Korean Journal of Computational Design and Engineering
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• v.11 no.1
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• pp.1-10
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• 2006

This paper addresses B-spline curve approximation of a set of ordered points to a specified toterance. The important issue in this problem is to reduce the number of control points while keeping the desired accuracy in the resulting B-spline curve. In this paper we propose a new method for error-bounded B-spline curve approximation based on adaptive selection of dominant points. The method first selects from the given points initial dominant points that govern the overall shape of the point set. It then computes a knot vector using the dominant points and performs B-spline curve fitting to all the given points. If the fitted B-spline curve cannot approximate the points within the tolerance, the method selects more points as dominant points and repeats the curve fitting process. The knots are determined in each step by averaging the parameters of the dominant points. The resulting curve is a piecewise B-spline curve of order (degree+1) p with $C^{(p-2)}$ continuity at each knot. The shape index of a point set is introduced to facilitate the dominant point selection during the iterative curve fitting process. Compared with previous methods for error-bounded B-spline curve approximation, the proposed method requires much less control points to approximate the given point set with the desired shape fidelity. Some experimental results demonstrate its usefulness and quality.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.5
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• pp.667-671
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• 1999

The purpose of this study was to determine the number of skin cold receptor in Korean adult as a part of the study to investigate thermal physiological characteristics of Korean. For this 10 healthy subjects were placed in a climatic chamber and received cold stimulation of 1$0^{\circ}C$ on skin surface of each measuring site with a thermo-stimulator. As a result of cold spot measurement we found 23 points/cm2 at face 13. points/cm2 at chest 16 points/cm2 at abdomen 11 points/cm2 at back 14 points/cm2 at upper arm 16 points/cm2 at forearm 18 points/cm2 at back of the hand 15 points/cm2 at thigh 8 points/cm2 at leg 12 points/cm2 at dorsum of foot 8 points/cm2 at sole of foot in male subjects and in female subjects we fund 18 points/cm2 at face 13 points/cm2 at forearm 11 points/cm2 at at back of the hand 8 points/cm2 at palm 9 points/cm2 at thigh 6 points/cm2 at leg 8 points/cm2 at dorsum of foot 2 points/cm2 at sole of foot. The distributions of cold spots varied in different regions of the body surface and was exceptionally dense in the facial skin. There were some differences among other researchers' results but the cause of those differences are not yet known those are due to individual or methodological difference.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.9 no.2
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• pp.29-43
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• 2005

We consider a surface reconstruction problem from geometrical points (i.e., points given without any order) distributed on a series of smooth parallel cross sections in ${\mathbb{R}}^3$. To solve the problem, we utilize the natural points ordering method in ${\mathbb{R}}^2$, described in [18], which is a method of reconstructing a curve from a set of sample points and is based on the concept of diffusion motions of a small object from one point to the other point. With only the information of the positions of these geometrical points, we construct an acceptable surface consisting of triangular facets using a heuristic algorithm to link a pair of parallel cross-sections constructed via the natural points ordering method. We show numerical simulations for the proposed algorithm with some sets of sample points.

• Korean Security Journal
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• no.1
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• pp.51-71
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• 1997

The private security has forty years history and it seems not to have points in exteriors. But it has many points in interior. If these points improved, our private security can develop. I discuss the development of the private security in Chapter 2 and the points in Chapter 3, and conclude in the last Chapter. If we follow the precepts, and develop a good points and improve a week points, the future of our private security will be better.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.3
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• pp.615-622
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• 2007

In general, Harris detector is commonly used for finding salient points in watermarking systems using feature points. Harris detector is a kind of combined comer and edge detector which is based on neighboring image data distribution, therefore it has some limitation to find accurate salient points after watermark embedding or any kinds of digital attacks. In this paper, we have used cross reference points which use not data distribution but geometrical structure of a normalized image in order to avoid pointing error caused by the distortion of image data. After normalization, we find cross reference points and take inverse normalization of these points. Next, we construct a group of triangles using tessellation with inversely normalized cross reference points. The watermarks are affine transformed and transformed-watermarks are embedded into not normalized image but original one. Only locations of watermarks are determined on the normalized image. Therefore, we can reduce data loss of watermark which is caused by inverse normalization. As a result, we can detect watermarks with high correlation after several digital attacks.

• Journal of information and communication convergence engineering
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• v.10 no.1
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• pp.1-4
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• 2012

Given separated points divided by a line, called a wall, in a plane, we aim to make a gate in the wall to connect the separated points to each other. In this setting, the problem is to find a location for the gate that minimizes the average distance between the points. The problem is a variant of the well-known facility location problem, which is extensively studied in the fields of operations research, location theory, theoretical computer science, and so on. In this paper, we consider the $L^1$-distance of the points in the plane. The points are projected onto the wall and so the problem is transformed to a proximity problem of points on a line. Then it is shown that the transformed problem is related to the weighted median problem of points on the line. Therefore, we obtain an O(n log n)-time algorithm to solve our problem.

• The Mathematical Education
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• v.55 no.3
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• pp.335-355
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• 2016

The purpose of this study is to analyze tasks to find intersection points of a function and its inverse function. To do this, we produced a task and 64 people solved the task. As a result, most people had a cognitive conflict related to inverse function. Because of over-generalization, most people regarded intersection points of a function and y=x as intersection points of a function and its inverse. To find why they used the method to find intersection points, we investigated 10 mathematics textbooks. As a result, 23 tasks were related a linear function, quadratic function, or irrational function. 21 tasks were solved by using an equation f(x)=x. 3 textbooks presented that a set of intersection points of a function and its inverse was not equal to a set of intersection points of a function and y=x. And there was no textbook to present that a set of intersection points of a function and its inverse was equal to a set of intersection points of $y=(f{\circ}f)(x)$ and y=x.

• Journal of Korean Home Economics Education Association
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• v.5 no.1
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• pp.133-141
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• 1993

The ability of the meal management of the middle and high school girls in kangweon area was surveyed by Likert scale questionnaire. The results were as follows: 1. The ability of the meal menagement of the middle school girls have good marks in table etiquette as 3.93 point, in using cooking apparatus as 3.86 points, in sanitation management as 3.76 points and in food selection as 3.70 points, but not so good in food preparation as 3.56 points, in meal planning as 3.22 points and in table setting as 3.20 points. 2. For the high school girls they have good marks in table etiquette(3.99 points), using cooking apparatus(3.96 points) food selection(3.95 points) and sanitation management(3.93 points) using cooking apparatus(3.96 points), food selection(39.5 points)and sanitation managment (3.93 points), but not so good in food preparation(3.64 points) meal planning and sanitation manabement(P<0.001) but no significant difference in food preparation, using cooking apparatus and table etiquette between middle and high school girls. In general they have a significant difference in ability of meal management between middle and high school girls.

• International Journal of Knowledge Content Development & Technology
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• v.9 no.2
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• pp.65-89
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• 2019

This study has the aim of developing an evaluation index that can help evaluate the reliability of the information resources of institutions retaining humanities assets for the purposes of laying out the foundation for providing one-stop portal service for humanities assets. To this end, the evaluation index was derived through the analysis of previous research, case studies, and interviews with experts, the derived evaluation index was then applied to the humanities assets retaining institutions to verify the utility. The institutional information resources' reliability evaluation index consisted of the two dimensions of the institutions' own reliability evaluation index. The institution provided a service and system evaluation index. The institutions' own reliability evaluation index consisted of 25 points for institutional authority, 25 points for data collection and construction, 30 points for data provision, and 20 points for appropriateness of data, for a total of 100 points, respectively. The institution provided service and system evaluation indexes consisting of 25 points for information quality, 15 points for appropriateness (decency), 15 points for accessibility, 20 points for tangibility, 15 points for form, and 10 points for cooperation, for the total of 100 points, respectively. The derived evaluation index was used to evaluate the utility of 6 institutions representing humanities assets through application. Consequently, the reliability of the information resources retained by the Research Information Service System (RISS) of the Korea Education & Research Information Service (KERIS) turned out to be the highest.