• Journal of Advanced Marine Engineering and Technology
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• 제22권4호
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• pp.505-514
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• 1998

Flow pattern of air-water two phase flow depends on the conditions of pressure void fraction and channel geometry. We classify the flow pattern by measuring the output signal of the conductivity probe. under the classified flow pattern we mount a visualization equipment on the test section and take pictures. We vary the concentration of pure solvent and polymer to measure local void fraction. We know that the maximum point position of local void fraction distribution move from the center of the pipe to the wall of the pipe as JSL increase when JSA is constant in two phase flow. But we find that the maximum point position of local void friction move from the wal of the pipe to the center of the pipe when polymer concentration increase.

• 한국지형학회지
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• 제23권2호
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• pp.61-70
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• 2016

This study intended to analyze the spatial distribution of two types of weeding song (Short Bang-a and Sangsa ryu) and how geomorphic elements influence the propagation of the songs in Chungcheongbuk-do area. The distribution of the two types of song was mapped as point data. According to the result, both types showed similar distribution pattern. In order to figure out the reason of this similarity, the distribution pattern of songs was analyzed at various scales based on geomorphic elements including river, mountain and lineament. The result showed that most of distribution pattern of songs followed the lineament direction. Also, the spatial continuity among mountain that was formed by large and small lineament in various directions could be the path of the cultural diffusion. If the lineament with same direction does not intersect other lineament that have different direction, spatial continuity would be blocked. Consequently it was confirmed that propagation of songs has not spread smoothly.

• Journal of the Optical Society of Korea
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• 제13권1호
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• pp.75-79
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• 2009

A four beam interference optical system for laser micro structuring using a pulse laser was demonstrated. The four beam interference optical system using a pulse laser(picosecond laser) can fabricate micro structure on mold material(NAK80) directly. Micro structure on the polymer can be reproduced economically by injection molding of the micro structure on the mold material. The four beam interference optical system was composed by the DOE(Diffractive Optical Element) and two lenses. The laser intensity distribution of four beam interference was explained by an interference optics point of view and by the image optics point of view. We revealed that both views showed the same result. The laser power distribution of a $1{\mu}m$ peak pattern was made by the four beam interference optical system and measured by the objective lens and CCD. A $1{\mu}m$ pitch dot pattern on the mold material was fabricated and measured by SEM(Scanning Electron Microscopy).

• Journal of Forest and Environmental Science
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• 제34권6호
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• pp.419-428
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• 2018

Spatial point-patterns analyses were conducted to provide insight into the ecological process behind competition and mortality in two lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) stands, one in the Lower Foothills, and the other in the Upper Foothills natural subregions in the boreal forest of Alberta, Canada. Spatial statistical tests were applied to live and dead trees and included Clark-Evans nearest neighbor statistic (R), nearest neighbor distribution function (G(r)), and a variant of Ripley's K function (L(r)). In both lodgepole pine plots, the results indicated that there was significant regularity in the spatial point-pattern of the surviving trees which indicates that competition has been a key driver of mortality and forest dynamics in these plots. Dead trees generally showed a clumping pattern in higher density patches. There were also significant bivariate relationships between live and dead trees, but the relationships differed by natural subregion. In the Lower Foothills plot there was significant attraction between live and dead tees which suggests mainly one-sided competition for light. In contrast, in the Upper Foothills plot, there was significant repulsion between live and dead trees which suggests two-sided competition for soil nutrients and soil moisture.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1532-1534
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• 1999

Electrical treeing phenomenon, regarded as pre-breakdown which accelerates aging process leading an insulation to the complete breakdown, is with no doubt extremely fatal to the performance of the insulation. Investigated in this paper is electrical treeing representing local dielectric failure according to flow pattern, the flow history of liquid polyethylene formed during the extrusion process. Experiments of electrical tree initiation by means of ramp tests were conducted using newly developed electrode system with point-to-point structure. Constant voltage tests were also carried out with the electrode system to estimate the life time of the insulation. Results were analyzed using statistical method such as Weibull distribution.

• 품질경영학회지
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• 제27권4호
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• pp.143-152
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• 1999

In Shewhart control chart, the average run length(ARL) is calculated using the mean of a conventional geometric distribution(CGD) assuming a sequence of identical and independent Bernoulli trials. In this, the success probability of CGB is the probability that any point exceeds the control limits. When the process is in-control state, there is no problem in the above assumption since the probability that any point exceeds the control limits does not change if the in-control state continues. However, if the out-of-control state begins and continues during the process, the probability of exceeding the control limits may take two forms. First, once the out-of-control state begins with exceeding probability p, it continues with the same exceeding probability p. Second, after the out-of-control state begins, the exceeding probabilities may very according to some pattern. In the first case, ARL is the mean of CGD with success probability p as usual. But in the second case, the assumption of a sequence of identical and independent Bernoulli trials is invalid and we can not use the mean of CGD as ARL. This paper concentrate on that point. By adopting one generalized binomial distribution(GBD) model that allows correlated Bernoulli trials, generalized geometric distribution(GGD) is defined and its mean is derived to find an alternative ARL when the process is in out-of-control state and the exceeding probabilities take the second form mentioned in the above. Small-scale simulation is performed to show how an alternative ARL works.

• 구강회복응용과학지
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• 제29권1호
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• pp.59-68
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• 2013

이 논문의 목적은 시간에 따른 교합의 변화를 측정할 수 있는 T-scan system을 이용하여 젊은 성인 남성(33명)정상교합에서의 하악골 측방운동 시 교합접촉 양상을 분석하는 것이다. 정해진 하악 위치에서의 교합접촉이 아닌, 기능적 범위 내에서 비작업측 교합이개 시점에서의 교합접촉 양상을 분류하고 분류된 군 간에 교합이개 시간, 측방유도 시 견치가 담당하는 교합력의 비율, 측방운동 시 가해지는 교합력 등을 비교하였다. 연구 결과 기존의 분류와는 다른 측방접촉들이 존재하였고 군기능 유도가 우세하게 나타났다. 교합이개 시간, 측방유도 시 견치가 담당하는 교합력의 비율, 측방운동 시 가해지는 교합력 등에서 군 간의 유의한 차이를 나타내었다. T-scan system은 교합접촉 양상을 분류하고 교합력, 교합이개 시간, 견치가 담당하는 교합력 비율 등의 항목을 비교 분석하는데 있어서 유용한 도구이다.

• 비교문화연구
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• 제43권
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• pp.459-483
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• 2016

The main objective of this paper is to test the major prediction of the Aspect Hypothesis on interlanguage narratives collected from 171 Ibibio ESL learners in a classroom setting using sets of picture stories. Aspect Hypothesis predicts that lexical aspectual classes of verbs would determine the pattern of acquisition and distribution of tense-aspect morphology at the very early stages of L2 acquisition of tense-aspect verbal morphology. That is, telic verbs would be marked with the past tense-aspect verbal morphology before atelic verbs in the interlanguage of ESL learners irrespective of their L1 background. The results of our data analyses show a significant effect from the lexical aspect on the acquisition and distribution of tense-aspect morphology with chi-square statistics of ($x^2=196.92$,df = 6, n = 1664, p = <.0001). However, the effect of the lexical aspect is shown to be more prominent among Ibibio ESL learners at higher levels of proficiency. This is contrary to the prediction regarding Aspect Hypothesis. The paper concludes that the influence of the lexical aspect on the pattern of acquisition and distribution of tense-aspect morphology may be universal but the actual point along the developmental pathway when such influence is obtainable is yet to be determined. This calls for more research into the pattern of the L2 acquisition of tense-aspect verbal morphology.

• 한국의류산업학회지
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• 제12권2호
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• pp.194-202
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• 2010

There may be some problems in size fitness for ready-made-clothes purchasers with Obese body shape. The purpose of this study was to improve the wearing comfort of Junior-High School Girls' slacks by setting grading points and developing grading rules proper to the obesity. The subjects in this study was over 23 kg/m2 of the BMI. The subjects were 124 Junior-High School Girls of 12 to 14 year-old. The results of this study are as follows: (1) The size intervals of waist girth and hip girth were 3 cm and 4 cm respectively. The sizing system, which had frequencies more than 5%, was classified 8 cases. The majority segment is 76-97 size accounting for the 11.29% of subjects. (2) The measurements on 8 size from two groups after drawing slacks pattern on them revealed that the changed values of slacks front and back on the grading point marked are differ, indicating that it is needed to apply body shape. (3) The evaluation on the appearance for wearing slacks showed relatively high score, indicating that the grading between sizes within each group was effective. The studies on the body size distribution on each obesity pattern and on the setting size system reflecting characteristics of each body shape should be performed continuously.

• 한국의류산업학회지
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• 제11권5호
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• pp.771-778
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• 2009

There may be some problems in size fitness for ready-made-clothes purchasers with fatty body shape especially for them with abdominal obesity. The purpose of this study was to improve the wearing comfort of Middle-aged women slacks by setting grading points and developing grading rules proper to the abdominal obesity. The subjects in this study was over $25kg/m^2$ of the BMI, over 85cm of waist, and over 0.8 of WHR. A total of 176 Middle-aged women satisfyingthem were enrolled. The results of this study are as follows: (1) The majority segment is 85-94 size accounting for the 11.36% of subjects. (2) The measurements on 11 size from three groups after drawing slacks pattern on them revealed that the changed values of slacks front and back on the grading point marked are differ, indicating that it is needed to apply body shape and age specific grading rule. (3) The evaluation on the appearance for wearing slacks showed relatively high score, indicating that the grading between sizes within each group was effective. The studies on the body size distribution on each obesity pattern and on the setting size system reflecting characteristics of each body shape should be performed continuously.