• 제어로봇시스템학회논문지
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• 제22권9호
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• pp.710-715
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• 2016

Due to its simplicity and high reliability, the box-counting(BC) method is one of the most frequently used techniques to estimate the fractal dimensions of a binary image with a self-similarity property. The fractal calculation requires data sampling that determines the size of boxes to be sampled from the given image and directly affects the accuracy of the fractal dimension estimation. There are three non-overlapping regular grid methods: geometric-step method, arithmetic-step method and divisor-step method. These methods have some drawbacks when the image size M becomes large. This paper presents a BC algorithm for enhancing the accuracy of the fractal dimension estimation based on a new sampling method. Instead of using the geometric-step method, the new sampling method, called the coverage ratio-step method, selects the number of steps according to the coverage ratio. A set of experiments using well-known fractal images showed that the proposed method outperforms the existing BC method and the triangular BC method.

• Wind and Structures
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• 제29권6호
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• pp.389-403
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• 2019

In this study, two original spectral representations of stationary stochastic fields, say the continuous proper orthogonal decomposition (CPOD) and the frequency-wavenumber spectral representation (FWSR), are derived from the Fourier-Stieltjes integral at first. Meanwhile, the relations between the above two representations are discussed detailedly. However, the most widely used conventional Monte Carlo schemes associated with the two representations still leave two difficulties unsolved, say the high dimension of random variables and the incompleteness of probability with respect to the generated sample functions of the stochastic fields. In view of this, a dimension-reduction model involving merely one elementary random variable with the representative points set owing assigned probabilities is proposed, realizing the refined description of probability characteristics for the stochastic fields by generating just several hundred representative samples with assigned probabilities. In addition, for the purpose of overcoming the defects of simulation efficiency and accuracy in the FWSR, an improved scheme of non-uniform wavenumber intervals is suggested. Finally, the Fast Fourier Transform (FFT) algorithm is adopted to further enhance the simulation efficiency of the horizontal stochastic wind velocity fields. Numerical examplesfully reveal the validity and superiorityof the proposed methods.

• 한국습지학회지
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• 제5권1호
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• pp.15-27
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• 2003

The fractal study in river basin has been performed for the sinuosity of an individual stream and bifurcation of the stream network. The previous studies has suggested many methods or equations for the fractal dimension estimation in a river network. This study used those many equations for the estimation of fractal dimensions on the streams such as Bokha, Gonjiam, and Pocheon streams. The estimated dimensions are in the range of 1 to 1.359 for the individual stream and 1.634 to 2 for the stream network. The most of equations were suggested based on the assumption of self-similarity of a river basin for the individual stream and stream network. However, the real river basin could be characterized by self-affinity rather than self-similarity. Even though we estimate the dimensions by using many equations, we could not recommend which one is better equation for the estimation of fractal dimension. This might be from the self-similarity assumption of equations. Therefore, the assumption and research work of self-affinity will be needed for the appropriate estimation of fractal dimension in river basin.

• 대한치과교정학회지
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• 제18권1호
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• pp.217-225
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• 1988

This study was undertaken to examine relationship between tooth size and arch dimension in dental crowding. Two groups of dental casts were selected on the basis of dental crowding. One group, consisting of 51 pairs of dental casts (24 male and 27 female), exhibited remarkable dental crowding. A second group, consisting of 60 pairs of dental casts (30 male and 30 female), exhibited little or no crowding. Mean and standard deviation of the following parameters were used to compare two groups. individual and collective mesiodistal tooth diameters, buccal and lingual arch widths and arch area. The following results were obtained. 1. The crowed group revealed larger tooth size than noncrowded group. (p < 0.01) 2. The crowded group smaller maxillary dental arch dimension than noncrowded group except lingual arch width at canine region. (p < 0.01) 3. The corwded group revealed smaller mandibular dental arch dimension than noncrowded group except lingal arch width at second premalar region in the male and buccal arch width at canine, premolar region in the female. (p < 0.01) 4. The crowded group revealed smaller arch area than noncrowded group in the female (p < 0.01), but there was no significance in the male.

• 과학기술학연구
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• 제2권2호
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• pp.123-143
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• 2002

이 논문의 목적은 과학지식사회학의 대표적 사례 연구에 해당하는 보일의 공기펌프에 대한 세이핀의 연구를 중심으로 사회구성주의의 타당성을 검토하는 것이다. 나는 이 글에서 과학적 활동은 인식적 차원과 비인식적 차원을 갖고 있으며 사회구성주의는 후자를 강조한 나머지 전자의 중요성을 무시함으로써 과학적 지식에 대한 균형 잡힌 이해를 제공할 수 없다는 것을 주장한다. 논의 순서는 우선 진공펌프에 관한 보일과 홉스의 논쟁의 인식적 차원이 검토되고 이어서 비인식적 차원을 강조하는 세이핀의 설명이 검토된다. 이러한 논의를 바탕으로 세이핀의 사회구성주의의 한계점이 지적된다.

• 한국패션뷰티학회지
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• 제2권3호
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• pp.60-67
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• 2004

Representing all the parts of human body visible to fit into the script, it can be told that real make-up has been done. Based on the point of view. it will be different from others. To become the beautiful, beauty make-up has to be done, however, to be someone described in the script or any other factions after analyzing characters of being represented, special make-up fits into that category. In the special make-up, there are two different pins: one is 2 dimension make-up which is describing images using dots, lines and colors and other is 3 dimension which will include necessary shapes to figure. Even though there seems to be different between modern technologies and handy work, since accurate measures and graphics have to be used to make perfect character describes in the script, more investments and studies than before have to be made. Real attraction of 3 dimension make-up is building up the images and shapes using unseen abstract images having analyzing characters. It will be decided in the working process called modeling. As having distinguished this part from other make-ups as named prosthetics make-up, proposing means and measures of prosthetics make-up will actually help the others who are studying make-up.

• 한국정보처리학회논문지
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• 제7권3호
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• pp.992-999
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• 2000

Textile dimension inspection is one of the basic issues in the textile dyeing and finishing industry. And also, it a plays an important role in the quality control of total fabric products. In this paper, we implement a real-time textile dimension inspection system which detects various real defects, defects positions of textile and the density of textiles. The proposed method consists of textile density measurement algorithms with zone-occurrence features from subband image which detect various types of real defects. The performance of the proposed method is tested with a number of real textile samples with 10 types of defects and three basic structures of textile. By the dimension inspection of textile at continuous stages in the fabrication process, it is possible to measure the density of textile up to 150m/min and to detect the defect of textile at real time within $\pm$1% error percentages. And also it can be monitored the condition of textile throughout at all the significant working process and can be improved textile quality.

• 한국어학
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• 제48권
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• pp.333-354
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• 2010

When defining the word related to passive and causative in Korean dictionary, the meaning of headword can be explained by linking them to other related words. The link could be expressed into two forms; the one is 'passive verb causative verb of A' and the other is 'passive form causative form of A.' Whichever the dictionary takes, the important thing is that the content to which it refer should be correct. However the format of 'passive verb causative verb of A' and 'passive form causative form of A' is problematic because the definition of headword does not contain semantic information but syntactic or morphological information. Generic concept 'passive form causative form' and 'passive verb causative verb' refers to respectively morphological and syntactic level but specific concept 'A' refers to semantic level. These morphological, syntactic and semantic level can not be a same dimension so the size of their denotation can not be compared. The way of transform syntactic dimension 'passive verb causative verb' and morphological dimension 'passive form causative form' into semantic dimension is removing 'verb' and 'form' from 'passive verb causative verb' and 'passive form causative form' respectively. Therefore the expression 'passive verb causative verb of A' or 'passive form causative form of A' ought be changed into 'passive causative of A.'

• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1175-1184
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• 2022

The pore structure of uranium-bearing sandstone is one of the critical factors that affect the uranium leaching performance. In this article, uranium-bearing sandstone from the Yili Basin, Xinjiang, China, was taken as the research object. The fractal characteristics of the pore structure of the uranium-bearing sandstone were studied using mercury intrusion experiments and fractal theory, and the fractal dimension of the uranium-bearing sandstone was calculated. In addition, the effect of the fractal characteristics of the pore structure of the uranium-bearing sandstone on the uranium leaching kinetics was studied. Then, the kinetics was analyzed using a shrinking nuclear model, and it was determined that the rate of uranium leaching is mainly controlled by the diffusion reaction, and the dissolution rate constant (K) is linearly related to the pore specific surface fractal dimension (D_S) and the pore volume fractal dimension (D_V). Eventually, fractal kinetic models for predicting the in-situ leaching kinetics were established using the unreacted shrinking core model, and the linear relationship between the fractal dimension of the sample's pore structure and the dissolution rate during the leaching was fitted.

• 교육시설
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• 제10권5호
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• pp.5-14
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• 2003

The purpose of this survey study is to analyse the playground dimension of elementary school. To complete this mission, it is necessary to drive out elementary school have a lower dimension standard of playground through literal survey. Then, questionnaire and observation survey have been performed to teachers majored in physical education and these are focused on playground dimensions. The field survey study will provide the basic data for calculating proper playground dimensions and design source for planning space program of the school. The result of this survey study are as follows ; First, The Area of 'Gyo-ghi' is decreasing, and the land area of being used for 'Gyo-sa' is increasing. So the area of playground is decreasing. Second, The respondents require a playground size enough to contain 100m running track for testing the physical ability of students. But it is not possible to do so in current domestic condition, it is necessary to revise of the standard of physical test or enact a new one. Third, to solve the problems deviating from the playground size, the respondent suggests that set up a new gym or variable-size playgrounds rather than a large one Fourth, because playground has so much functions as rest, playing, walking and jogging etc besides physical education, it is necessary to consider the spaces for rest and play, when plan a tower-type school or small school.