• 전기학회논문지P
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• 제59권4호
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• pp.473-476
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• 2010

In this paper, we analyzed the short circuit current of a low voltage direct current distribution system. For the analysis, we performed the modeling of the low voltage direct current distribution system with a 6-pulse three-phase thyristor rectifier using the PSCAD/EMTDC, surveyed impedance of sources, transformers and distribution lines to run a simulation. A result of the simulation is that short circuit currents of the direct current distribution system with the rectifier decreased due to a thyristor-ON-resistance(Ron). But in case of the low thyristor-ON resistance, output fault current of the rectifier increased over three-phase short circuit current of an AC power system without a rectifier by regular ratio of the rectifier. Because the output fault current of the rectifier can increase over interrupting the capacity of circuit breakers, studying short circuit currents of a low voltage direct current distribution system with a rectifier is necessary for introducing the direct current distribution systems.

• 유통과학연구
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• 제19권2호
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• pp.77-86
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• 2021

Purpose: This study focuses on the buying Korean products by Chinese consumers through overseas direct purchase as a distribution means (tool) because they are interested in Korean products because of their excellence. Major variables are national brand, curiosity, price, product quality. Research design, data, and methodology: To make effective analysis, several tools and programs for analysis are used with SPSS Statistics ver. 23.0 and AMOS 23.0. Results: National brand, price, product quality have affirmative impacts on satisfaction and repurchase through overseas direct purchase. But curiosity does not have. Among them the most important variable is product quality. This is the same as Chinese consumers think product quality is the most valuable one when buying Korean products through overseas direct purchase. Next one is price. The last one is a national brand. Conclusions: Among the variables of overseas direct purchase, product quality has the biggest impact on satisfaction and repurchase positively. This means that many Chinese consumers are interested in product quality manufactured in Korea. Also Korean product quality is better than that of China until now. Korean companies should, strongly and continuously, have to improve the quality of Korean products because China focuses on product quality in the distribution process in the national base.

• 한국지역사회생활과학회지
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• 제15권3호
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• pp.71-84
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• 2004

Recently the globalization of agriculture by the WTO has brought crisis to Korean farmers. Value added agricultural products is the one of the strategies to sustain fanning. The idea for the project traditional fermented soy paste production and distribution was developed by the Gyeonggi-do Agricultural Research Institute. It was necessary to know the purchase condition and consumer needs for production distribution of the soy products. This study aims to investigate the consumers' need analysis of direct-deal soy products and the conditions of a purchase. A questionnaire was administered to 590 subjects living in Gyeonggi-do, Korea. The 107 subjects procured soy paste to buy with the reason of ignorance of preparation (39.2%) and the difficulty of storage and care (31.8%). When selecting the product 95.3%, previous experience (41.1 %) and comparison of each product (34.6%) were major answers, wanted direct-deal purchase from producers if implemented. 142 subjects(24%) experienced direct deal with producers. The main direct route was government and public offices( 42.4 %). The reason for direct purchase was confidence of agricultural products(77.5%). Delivery of 4kg of soy paste and 1.8 L of soy sauce in a glass container (43.0%) was favored twice a year. The kind of soy products for consumers' needs was Doenjang(57.8%) and Gochujang(18.3%). The preferred methods direct-dealing of soy products was direct order(59.9%) after validation, delivery gate to gate (44.2%) and by the internet(4.9%). The results of the study shows that the types of production would have the kinds and quantities diversity with confidence, sanitation, and safety. To regain successful, traditional tastes it is necessary to develop reliable and tasteful products for consumers and develop promotional material.

• 한국콘텐츠학회논문지
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• 제5권1호
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• pp.217-227
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• 2005

본 논문은 성능이 우수한 DirectX 기반 다채널 영상 감시 시스템을 설계 구현하고, 성능 분석한 결과를 제시한다. 본 논문의 시스템은 크게 디스플레이 서브시스템, 저장 서브시스템, 검색 및 재생 서브시스템으로 구성된다. 디스플레이 서브시스템은 빠른 디스플레이, 채널 간 디스플레이 동기 및 tearing effect 개선을 위해, DirectDraw의 H/W 가속 기능과 overlay, flip 기능을 효율적으로 이용하여 설계되었다. 저장 서브시스템은 저장 속도 개선을 위해, DirectShow 필터 기반 다중 쓰레드 구조로 설계되어 캡쳐 장치에서 획득되는 다채널의 영상 스트림이 채널별로 압축 저장되고 채널 간 데이터 병목 현상이 최소화되도록 하였다. 검색 및 재생 서브시스템에는 효율적인 인덱스 파일 구조와 영상 데이터 저장 구조, 재생 시에 채널별 동시 재생이 가능하도록 한 효율적인 재생 구조를 설계 구현하여 보다 빠른 재생 및 검색이 가능하도록 하였다. 실험결과, 제안된 시스템이 기존 시스템보다 저장 속도는 최고 2배 까지, 검색 및 재생 속도는 최고 3.5배 정도까지 개선되었음이 확인되었다.

• 한국태양에너지학회 논문집
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• 제26권3호
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• pp.53-62
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• 2006

Since the direct normal radiation and clear day are a main factor for designing any solar thermal and photovoltaic concentrating system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of direct normal radiation and clear day in Korea. The data utilized in the investigation consist of direct normal radiation collected for 14 years('90. 12${\sim}$2004. 12) and clear-day collected for 23 years($1982{\sim}2004$) at measuring stations across the country. The analysis shows that the annual-average daily direct normal radiation is 5.4 kWh/m2 and the annual-average total clear-day is 92.7 days in Korea. We also constructed the contour map of direct normal radiation and clear-day in Korea by interpolating actually measured data across the country.

• Journal of Biosystems Engineering
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• 제23권5호
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• pp.439-444
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• 1998

Effects of the number of spans, orientation and latitude on the transmissivities of direct and diffuse solar radiation in multispan glasshouse were analyzed using a computer simulation model (Kim and Lee, 1997). The number of spans did not affect the transmissivity of diffuse solar radiation, ranging 60∼61%. The transmissivities of direct solar radiation were 55∼64% for E-W orientation and 47∼70% for N-S orientation in ten multispan glasshouse. There was no effect of the latitude on the transmissivity of direct solar radiation in domestic regions. Differences in the transmissivity of direct solar radiation between single-span and multispan glasshouse were significant for E-W orientation during winter season; however, those were relatively small for N-S orientation throughout the year. Transmissivity of direct solar radiation decreased with the increasing number of spans for E-W glasshouse, whereas those for N-S glasshouse was hardly affected by the number of spans.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.179-180
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• 2020

In the budgeting guidelines, there are rules for calculating design fee and direct costs. However, only the design fee is calculated excluding the direct cost, which causes the cost to be insufficient. Therefore, this study is designed to analyze representative cases where direct costs are insufficient, draw out problems, and propose a way to improve design fees.

• 제어로봇시스템학회논문지
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• 제11권6호
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• pp.550-557
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• 2005

The multivariate statistical analysis methods, using both multiple linear regression(MLR) and partial least square(PLS), have been applied to predict the reactor properties and the product quality of a direct esterification reactor for polyethylene terephthalate(PET) synthesis. On the basis of the set of data including the flow rate of water vapor, the flow rate of EG vapor, the concentration of acid end groups of a product and other operating conditions such as temperature, pressure, reaction times and feed monomer mole ratio, two multi-variable analysis methods have been applied. Their regression and prediction abilities also have been compared. The prediction results are critically compared with the actual plant data and the other mathematical model based results in reliability. This paper shows that PLS method approach can be used for the reasonably accurate prediction of a product quality of a direct esterification reactor in PET synthesis process.

• 터널과지하공간
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• 제15권5호
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• pp.344-351
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• 2005

터널 시공 중 계측한 변위 등으로 터널의 안정성을 재평가하기 위해 심플렉스 이론을 기초로 직접법 역해석 소프트웨어를 개발하고 그 정확성을 12 가지 조건에서 검증하였다. 이 소프트웨어는 FLAC을 부프로그램(subroutine)으로 하고 그것에 내장된 전산언어를 이용한 것이다. 변위 수 3-240개로 구성된 여러 가지 변위조합에 대한 역해석 검증결과 터널 주변의 계측위치와 입력변위의 개수에 관계없이 암반의 탄성계수와 초기응력 비를 구할 수 있었고 반복계산을 위한 출발값의 탄성계수와 초기응력 비에 관계없이 정해에 안정적으로 수렴되는 것을 확인하였다.

• 한국의상디자인학회지
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• 제25권4호
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• pp.1-11
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• 2023

The purpose of this study was to characterize the upper body shape of men in their 50s and 60s by analyzing direct measurement data. Sixty one direct measurement items were analyzed. Subjects (n = 752) were classified based on 5 factors into 4 body types. In order to acquire accurate upper body shape information by analyzing body type using the 8th Size Korea direct measurement data, body shapes were classified through factor and cluster analysis. As a result of the comparative analysis of the upper body measurements from the 5th to the 8th Size Korea measurement, it was found that waist circumference item tended to increase significantly from the 5th Size Korea measurements. The upper body type of middle aged males were classified using five factors: the trunk obesity factor, the trunk vertical factor, the width of the back shoulder, the vertical factor behind the back, and the length factor of the upper body. Middle-aged men were classified into four body types through cluster analysis. Type 1 is relatively short with big arms, Type 2 has wide shoulders and thin arms, and in Type 3, the upper body is relatively long. Type 4 is the most obese upper body.