• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2002년도 심포지엄
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• pp.31-36
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• 2002

This experiment was conducted to investigate the effects of turf grass growth to seedling rates and bed soil types. The results of this experiment were summarized as follows; the more increasing the seedling rates, the plant height and leaf length were longer, but the number of leaf and number of branch were fewer. In case of transplanting of turf grass seedling by rice transplanting machine, it might be considered that the proper alternative bed soil was sandy loam soil with regarding to the economic aspects. The maximum seedling rate of turf grass in the seedling tray for rice was 1,000 of seedling amount due to the nutrient competition with intensive seedling. As the results indicated, it might be recommended that the proper alternative bed soil was sandy loam soil with 1,000 of seedling rates in case of transplanting of turf grass seedling by rice transplanting machine.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1998년도 21세기 한반도 농업전망과 대책(한국작물학회.한국육종학회 공동주관 심포지움 회보)
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• pp.233-248
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• 1998

Food Self-sufficiency rate in Korea was 26.4 percent in 1996. It include $89.9{\%}$ for rice, $99.6{\%}$ for root and tuber crops, and $73.5{\%}$ for barley. To make things worse, self-sufficiency for wheat and corn were far less than 1 percent. As food is considered as weapon, every effort should be given to increase the self-sufficiency. In order to cope with expected food crisis, we suggest wheat and barley be grown in winter period, where there is climate fit. The aim of this paper is to survey systematically the status of food supply and demand of wheat and barley and to encourage farmers make double cropping systems with better stability in yield and economic return.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.443-445
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• 2008

Determination of allowable overtopping rate for coastal structure is a key point to determine the application of background of coastal structure while considering safety and economic efficiency. Thus, the accurate estimation of overtopping rate against coastal structure is essential. In general, estimation of overtopping against the coastal structure is based on an empirical formula or hydraulic experiment. In this study, we investigate the behavior of overtopping for rubble mound coastal structure with rubble armor stone and wave dissipating block using hydraulics experiment, and domestic or foreign design standard.

• Structural Engineering and Mechanics
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• 제46권4호
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• pp.549-569
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• 2013

A passive control using flaps will be an alternative solution for flutter stability and buffeting response of a long suspension bridge. This method not only enables a lightweight economic stiffening girder without an additional stiffness for aerodynamic stability but also avoid the problems from the malfunctions of control systems and energy supply system of an active control by winglets and flaps. A time domain approach for predicting the coupled flutter and buffeting response of bridge deck with flaps is investigated. First, the flutter derivatives of bridge deck and flaps are found by experiment. Next, the derivation of time domain model of self-excited forces and control forces of sectional model is reported by using the rational function approximation. Finally, the effectiveness of passive flap control is investigated by the numerical simulation. The results show that the passive control by using flaps can increase the flutter speed and decrease the buffeting response. The experiment results are matched with numerical ones.

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2007년도 춘계 지질과학기술 공동학술대회
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• pp.434-435
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• 2007

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• 한국식품저장유통학회지
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• 제3권1호
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• pp.39-53
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• 1996

Ginseng, one of the important economic crops, is processed into medicine, teas, beverages and even foods. Drying is the most important and burdensome work in the processing of ginseng, so development of ginseng dryer is needed for efficient drying and good quality of ginseng. Investigation of drying model is essential for development of ginseng dryer. Drying models for peeled ginseng were investigated to determine dominant drying factors and fitted with five selected drying models and an empirical model. Thompson and the empirical model showed best fit with the experimental data. Pother experiment is necessary to prove the superiority of the empirical models.

• 한국산학기술학회논문지
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• 제21권8호
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• pp.287-297
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• 2020

본 연구는 노후화된 대학 건물의 내부 단열 성능 향상에 대한 것으로, 대학교 건물 내 재실자의 생산성을 높이고 노후화된 건물의 단열효과를 높이기 위해 진행됐다. 본 논문은 한동대학교 느헤미야홀 건물 내 오피스 재실자의 단열 성능 향상에 대한 지속적인 요청에 응답하여 문제해결을 위해 진행된 연구라는 차별성을 가지고 있으며, 내부온도가 인접건물의 내부온도와 비교했을 때 낮음을 확인하여 연구 필요성에 대한 타당성을 검증하였다. 학교라는 건물의 특성을 고려해 내외부 단열 중 내부 단열을 주제로 단열재를 선택했다. 대학교 교수 오피스를 소형화시킨 모형 방을 만들어 시장에서 사용되는 내부 벽면 단열재를 설치해 실험을 진행했다. 실험 결과를 바탕으로 가열 시간과 실제 열전달 계수를 측정하여 단열효과를 분석하는 경제성 평가를 실시했다. 경제성 평가는 실험과 이론에 의해, 겨울철과 여름철 기준으로 각각 실시되었다. 연구결과, 느헤미야홀 60 개의 오피스에 아이소핑크(30 T)를 내 단열재로 도입하였을 때, 한 달에 겨울철에는 최대 총 1,071,600 원을 절약 할 수 있으며, 여름철에는 총 109,200 원을 절약할 수 있다.

• 노동경제논집
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• 제32권3호
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• pp.91-121
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• 2009

이 논문에서는 한국의 경우 개별 학군 내에서 사립학교와 공립학교 간에 학생 배분이 무작위로 이루어진다는 특수성을 이용하여, 사립학교가 공립학교에 비해 학생들의 성적향상 측면에서보다 효율적인지를 분석하기 위한 자연실험 분석을 실시하였다. 학군의 고정효과를 통제한 모델을 분석한 결과, 사립학교가 공립학교에 비해 학생들의 성적이 보다 향상된다는 통계적으로 유의미한 결과를 확인할 수 없었다. 단 상위 성적 계층의 여학생들의 경우, 사립학교 학생이 0.13 표준편차만큼 성적이 더 향상되는 것으로 나타났다.

• 한국작물학회지
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• 제46권1호
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• pp.53-56
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• 2001

Barley Yellow Dwarf Virus (BYDV), an aphid-borne luteovirus, is a major plant pathogenic disease causing a huge economic loss in the grain production of a wide range of Gramineae species throughout the world. It has been recently reported that BYDV also occurred frequently in wheat field of Korea. Here, we performed to develop the detection and classification methods of BYDV strains that were accomplished by reverse transcription-polymerase chain reaction (RT-PCR). Since there are high variations among BYDV strains, three pairs of primers were designed to detect BYDV strains such as PAV (Vic-PAV and CN-PAV) and MAV (primer A) simultaneously, specifically Vic-PAV(primer B), and MAV (primer C) based on the genomic RNA sequences of BYDV strains previously published. The validity of the primers was confirmed using several BYDV strains obtained from CIMMYT. Though three BYDV strains were able to be detected using primer A, PCR products were not distinguished between two PAV strains. It was possible to separate them with a restriction enzyme, EcoRI, whose restriction site was present in the amplified DNA fragment from Vic-PAV, but not from CN-PAV.

• Journal of Biosystems Engineering
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• 제26권4호
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• pp.371-378
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• 2001

This research devoted to develop an incubator that could make an optimum environment condition according to days of age for suckling pigs to decrease the mortality and improve the rate of the weight gain of the suckling pigs. Results obtained from this research summarized as follows: 1. Several experiments were carried out at the farm to find the effect of incubator developed for suckling pigs on weight gain by season. The total average gain of the weight of the treatment group was around 6∼22kg, and 6∼23kg higher than control group at the first experiment (April 19), at the second (July 30), and at the third (September 23), year of 2000 experiment, respectively. There were no significant differences ($\alpha$=5%) of the total weight gain among treatment groups. There was, however, a significant difference ($\alpha$=5%) of the total weight gain between the control and treatment groups and it was considered to be that the incubator had efficiency for weight gain of the suckling pigs. 2. The survival rate of the control group was 87% in the total sample number of 92, meanwhile, which of the experiment group was 98% in the total sample number of 50 suckling pigs. 3. Finally, economic analysis was executed for suckling pigs based on a farm size of breeding 500 sows. The results showed that a break-even point was around 9 months and the annual profit of ￦52,265,694 was expected after the break-even point.