• Journal of Biosystems Engineering
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• 제43권3호
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• pp.185-193
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• 2018

Purpose: The purpose of this study was to analyze the performance factors of a rotary impact-type thresher to develop a sesame and perilla thresher, specifically to analyze the cut length of the stems and the threshing rates based on the relationship between the blade velocity and feeding speed. Methods: The materials were dried within a range of 12.3-13.0% to test the impact cut by bending. The cut lengths of the perilla and sesame stems were categorized in 6 ranges (~7.0, 7.1-10.0, 10.1-13.0, 13.1-16.0, 16.1-20.0, 20.1- (cm)). For testing the cut length and threshing rate, the upward-rotating blade velocity was varied as 11.0 m/s, 13.5 m/s, and 22.3 m/s. Feeding speeds were changed from 0.1 m/s to 2.2 m/s by the inverter connected to the feed motor. The feed rate and threshing rates without cover-casing were evaluated with the factors of thresher testing. Results: The mean cut length of the stem decreased as the blade velocity increased and/or the feeding speed decreased. As the feed rate increased up to 17.5 g/s, the cut length distributions showed no significant difference. The threshing rate was 98.9% for sesame, and flexible according to the blade velocity and feeding speed of the perilla. Conclusion: Feeding material too fast could produce longer cut stem segments, therefore, a feeding speed less than 2.2 m/s is recommended. A blade velocity of 13.5 m/s is preferable for both sesame and perilla with regard to cut length and threshing rate.

• 복식문화연구
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• 제17권3호
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• pp.472-483
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• 2009

The purpose of this study is to analyse the effects of knit samples' mechanical properties on changes of skirt length of knit flared skirt, and to compare it to the knitting method of a seamless knitted flare skirt. So, I compared the appearance and 3-dimensional shape of a seamless knitted flare skirt with those of a fully cut knit flared skirt. For this study, 18 kinds of cut and sew or seamless knitted test garment were made. The data analysis methods used in this study were descriptive statistics, one-way ANOVA, correlation analysis, and regression analysis. The results are as follows: The result of the evaluation of knit samples' mechanical properties by the KES-FB system showed that elongation decreased as gauge increased and course direction was greatest among grain directions. The length change after wearing the knitted flare skirts appeared wholly equal to the seamless knitted, compared with the cut and sew. The change was biggest at $180^{\circ}$, 7G of the cut and sew. In grain direction, bias cut showed more than 1.2cm of length change. As the weight and thickness increased, the length changes become larger. The regression analysis indicated that the greatest contributive variables on the length changes were elongation, weight, and thickness.

• 한국연초학회지
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• 제27권2호
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• pp.201-206
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• 2005

In this work, we studied the effects of the moisture contents of cut tobacco on loose end of cigarettes. The loose end of the cigarette groups decreased with the increase of moisture contents of the cut tobacco and especially the loose end of A and C groups decreased to $31\%\;and\;52\%$ with the increase of $1\%$ moisture contents. $A-13.5\%\;and\;B-14.0\%\;and\; C-14.0\%$ moisture samples showed the increase of the weight ratio of cut tobacco over 1.4mm cut length but the decrease under 1.4mm cut length. We concluded that the main reasons were regarded to reduction of small fragment tobaccos caused by increase of moisture contents and exception of air-suction transport of tobaccos to cigarette making machine. In spite of the moisture increase of cut tobaccos under fixed EPD(encapsulated pressure drop), the hardness of Band C sample groups were maintained constantly except A group. This result means that under fixed EPD, the weight of cut tobacco in cigarette rods increases to compensate the reduction of pressure drop by moisture increase of cut tobaccos.

• 한국CDE학회논문집
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• 제2권3호
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• pp.186-194
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• 1997

This paper describes new methods to minimize the cutting time in zigzag milling operation of two dimensional polygonal surfaces. Previous works have been focused on mainly experimental approaches by considering some machining parameters such as, spindle speed, depth of cut, cutter traverse rate, cutter diameter, number of teeth, tool wear, life of tool, and so on. However, in this study, we considered two geometrical factors one by one in order to see the effect separately, which are the length of cut and the number of cutter traverse. In an N-sided concave or convex polygon, an algorithm has been developed which minimize the total length of cut. Also, a heuristic approach was used to minimize the number of cutter traverse.

• 한국연초학회지
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• 제28권1호
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• pp.23-30
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• 2006

In order to improve the final product quality, tobacco industry has gradually decreased the size and number of steams in the cigarette. Especially, steams bigger than $3{\times}3$ mm($length{\times}thickness$) and $2{\times}10$ mm($width{\times}length$) are not acceptable in the process as objectionable stems. A total number of 12 samples where the $length{\times}tickness$ samples were prepared by decreasing the present sample ($3{\times}3$ mm) with 1 mm up to $1{\times}1$ mm, and the $width{\times}length$ samples were prepared by decreasing the present sample ($2{\times}10$ mm) with 2 mm up to $2{\times}6$ mm for the stems in leaf and stems in expanded cut-tobacco were prepared to apply a fire ball drop test using stems. In addition, cigarettes were produced for these stems in order to analyze the forced fire ball drop including the burning, encapsulation and unencapsulation pressure drop and a single or unspecified direction combustion. Based on the results of the test, it was evident that the fire ball drop in the stems in expanded cut-tobacco presented a lower level than that of the stems in leaf. Also, the stems in expanded cut-tobacco presented a larger swelling and higher burning for a single direction than that of the stem in leaf. In addition, it was considered that the management criteria for objectionable stems should be changed as $3{\times}3$ mm and $2{\times}8$ mm for the $length{\times}thickness$ and $width{\times}length$ sample, respectively, in both steams in leaf and expanded cut-tobacco.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.690-692
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• 2003

본 논문에서는 main gate 50nm를 갖는 double gate MOSFET에서 side gate의 길이변화에 따른 주파수 특성을 조사하였다. side gate길이가 감소할수록 컷오프 주파수는 증가하는 것을 볼 수 있었다. 결과적으로 side gate 길이가 70nm일 때 최적의 동작 특성을 보였으며, 이때 컷오프 주파수는 41.4GHz로 매우 높은 컷오프 주파수를 갖음을 알았다.

• 한국가구학회지
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• 제27권3호
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• pp.165-174
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• 2016

To modularize the joints of Hanok, the bending strengths of butterfly joints between pre-cut and manual member were compared. Structural size joints were manufactured and the length, width and thickness of each tenon were produced with different sizes. The ultimate load of pre-cut members was 2 times higher than that of manual members. Degree of anchorage for the joints on pre-cut member was also superior to that of manual member. By the F-test results, a great influence between ultimate load and sizes of tenon was found. In result of multiple regression analysis, the length and thickness of tenon were showed proportion relationships with the ultimate load, but the width of tenon was showed inverse proportion with the ultimate load. The results of this study can be used to identify the relationships among the major influence factors. Futhermore, it might be used as basic data for modularization the joints of Hanok.

• 디지털융복합연구
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• 제16권10호
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• pp.479-484
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• 2018

일제 강점기 여성들 one length hair style의 변천사 및 형태학적 분석을 시도한 연구로서 선행논문과 저서를 바탕으로 형태, 질감, 색상 등 헤어디자인의 구성 요소들을 분석하여 다양한 형태의 one length hair style 커트가 가능해지는데 연구의 목적이 있다. 연구 결과 1910년-1920년대 one length hair style은 커트 길이의 단차가 전혀 없는 out line을 지닌 형태, 자연 그대로의 모발 질감, 자연 모발 색상을 보였다. 1930년대 one length hair style은 약간의 커트 길이의 단차를 보이면서 다이아몬드 형태, 자연스런 질감의 narrow wave, 과산화수소나 oxygenated water을 이용한 약간의 탈색이 이뤄졌다. 1940년대 one length hair style은 형태, 질감, 색상 면에서 화려한 미(美)를 추구하려는 특이점이 발견되지 않았다. 본 연구를 통해 one length hair style에 관한 심층적이고 세분화 된 후속 연구가 가능해지며, 헤어미용 교육의 기초 자료 및 뉴 모드의 트렌드 개발을 위한 초석으로 작용하리라 사료한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.234-241
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• 1999

Rails have residual stresses produced during manufacturing processes. The residual stresses play all important role on brittle fracture, fatigue strength and derailment by producing cracks in the web of rail. The web saw-cut test is a technique developed to measure the bulk longitudinal residual stress level. It is a simple mettled to estimate a stress intensity factor, $_{4}$ for a web crack by using the radii of curvature of the upper and lower portions of a cut rail. But according to this method, $_{4}$ varies along the rail length because the curvatures along tile rail length vary In this paper, tile residual stress was estimated by Finite Element Method and tile web saw-cut method. In addition tile variation of the residual stress with time was investigated.

• 화훼연구
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• 제19권4호
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• pp.197-201
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• 2011

본 연구는 고품질 절화백합 생산을 하기 위해 실제 유통 중인 7품종을 구주를 달리 하여 식재하고, 채화 후 구주와 품종이 절화품질에 어떠한 영향을 미치는지 알아보고자 수행하였다.절화품질을 측정한 결과, 화뢰장은 'Medusa', 품종, 절화장은 'Mother's Choice' 품종에서 가장 긴 것으로 확인되었다. 줄기휨각도는 'Mother's choice' 품종과 'Ismael' 품종을 제외한 모든 품종이 $30^{\circ}$ 이상으로 나타났다. 화경장, 화서장, 경경, 꽃 수, 중량 모두 구주가 클수록 좋은 결과를 보였다. 절화품질 중 화뢰장, 절화장, 꽃 수에 영향을 미치는 요인은 구주의 크기이며, 휨각도는 품종과 구주의 크기 모두 영향을 받지 않는 것으로 나타났다. 이와같이 절화품질은 품종보다는 구주에 영향을 받으며 크기가 커질수록 좋은 결과가 나타나는 것으로 확인되었다.