• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.271-274
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• 2001

Experiments on the yield strength of pipe connectors made of metal wire, joint pins, pole pipes, multi span insertion joints, and T-clamp joints used in pipe houses were conducted. The strength of connections of a pipe connector made of metal wire was adequate but it had a big difference according to loading direction. The collapse load of pipes connected with a joint pin was lower than that of single pipes. Also experimental results showed that pole pipes for use in a part of frame buried under the ground were safe, and the strength of multi span insertion joints should be increased. The resistant moment of T-clamp was about 13.7% of a single pipe.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.187-192
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• 2005

Pleurotus eryngii(King oyster) is one of the most promising mushrooms being produced on the domestic farms. The quality as well as quantity of Eryngii is sensitively affected by micro climate factors. To safely produce high-quality Eryngii all the year round, it is required that the environmental factors be carefully controlled by well designed structures equipped with various facilities and control systems. This study was carried out at the commercial mushroom cultivation houses to find out reasonable range of each environmental factor and yield together with economic and safe structures influencing on the optimal productivity of Eryngii. This experiment was conducted from Nov. 10, 2004 to Aug. 27, 2005 in Eryngii. cultivation houses. The environmental factors measured for this study were inside/outside temperature, relative humidity and $CO_2$ concentration in Pleurotus eryngii medium. In addition, the yield and quality of mushroom were made investigation. But the optimal productivity will be evaluated by considering the quality and quantity of mushroom production, energy requirements, facility construction and management cost, etc.

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1832-1834
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• 2009

A simple and safe method has been presented for conversion of olefins into bromohydrins using hydrogen bromide and hydrogen peroxide as bromide source by visible light induced within a very short time to get high yield bromohydrins along with a little mount dibromo-product. In this paper, cyclohexene is firstly carried out as the model substrate and investigated the bromination under HBr/$H_2O_2$ system using 150 W incandescent light irradiated in C$Cl_4$ within short time to get good yield of 2-bromocyclohexanol along with a little mount of 1,2-dibromocyclohexane; then, a series of alkenes are brominated to corresponding bromohydrins using the same protocol.

• Steel and Composite Structures
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• 제17권6호
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• pp.951-965
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• 2014

Point bending is commonly used for cambering and curving steel girders to large radii. In this system, a hydraulic ram or press is used to apply concentrated loads at selected points to obtain the required vertical (cambering) or horizontal (curving) curved profile from induced permanent deformations. This paper derives closed form solutions that relate loads to permanent deformations for horizontally curving wide flange steel beams based on their post-yield response. These solutions are presented in a parametric form to identify the relationship between key variables and their impact on the accuracy of the curving operation. It is shown that point bending could yield parabolic curved profiles that are within 1% of a desired circular curve if the span length to radius of curvature ratio (L / R) is less than 1.5 and the point loads are spaced at one third the beam length. Safe limits are then established on loads, strains and curvatures to avoid damaging the steel section. This leads to optimization of the point bending operation for inducing a circular profile in wide flange steel beams of any size.

• 한국유기농업학회지
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• 제23권2호
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• pp.281-289
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• 2015

In sustainable viticulture, green manure represents a safe and non-polluting way to bring large quantities of organic matter into the soil. The cultivation of green manure crops plays an important role in soil quality and sustainability of agricultural system. This study was conducted to evaluate the effects of green manure fertilization on yield and quality of the Campbell Early grape variety in the organic vineyard. Hairy vetch was the more productive green manure crop, yielding higher dry materials. Average yields of grape were significantly greater in hairy vetch+rye ($13.02ton\;ha^{-1}$) than nature weed ($11.65ton\;ha^{-1}$), respectively. The concentrations of total as well as individual anthocyanins were consistently higher with hairy vetch treatment compared with rye and nature weed, thus making the green manure cultivation is an environmentally friendly cultivation to increase the yield and anthocyanin contents in organic grape.

• 한국작물학회지
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• 제24권2호
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• pp.65-73
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• 1979

1. 파종기에 따른 묘대일수를 연장함에 따라 출수가 늦어졌으며, 품종별 출수기의 변이는 조생종은 묘대일수, 중만생종은 파종기의 영향을 받으며, 또한 동일 이앙기내에서 묘대일수 연장은 영양생장기간의 증대로 출수를 단축시켰다. 2. 파종기와 묘대일수 연장시 출수일수와 영양생장 기간은 짧아졌으며 기본영양 생장성이 작은 품종일수록 묘대일수 연장시 불시출수의 위험이 컸다. 3. 간장, 등숙비율은 묘대일수, 수수와 일수당입수는 파종기의 조만에 영향을 받으며 이들은 서로 상관을 보였다. 4. 등숙온도와 수량과도 상관을 보였으며 등숙기를 $23^{\circ}C$ 정도에서 출수개화하도록 조기이앙을 요한다. 5. 안전수량을 얻기 위해서는 조생종 6월 10일(40~50일묘), 중만생종 5월 30일(30~60일묘)이전 이앙을 안전작기로 본다.

• 한국유기농업학회지
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• 제19권spc호
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• pp.6-8
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• 2011

In order to produce the organic foods in accord with international standard, organic seeds should be used in organic farming. This study was conducted to establish the stable production of organic seed of waxy com by examining the growing characteristics, seed yield, and the economy for seed production by organic farming. The optimal sowing timing for organic seed production of waxy com hybrid was within 10 days of the $1^{st}$ of May with yield of 88~90% of conventional seed production. The optimal planting density was 41,600 plants/ha ($80{\times}30$ cm) for organic seed production of waxy com. The weight of 100 seeds and seed productivity increased at the planting ratio of 2:1 mother plant:male plant. Growth and seed production were improved by removing male plant at 7~10 days after silking. Organic fertilizer (mixed oil cake) was applied at a rate of 4~6 Mg/ha before sowing. Black plastic mulching was used for weed control. In addition, sex pheromone trap and bio-control agents were used for safe pest control and low labour cost.

• 한국작물학회지
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• 제49권4호
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• pp.305-308
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• 2004

Recently, with increasing concern for sustainable agriculture and safe agricultural products, organic farming has become widely adapted as an alternative to conventional farming. This study was conducted to investigate the effects of earthworm casts (EWC) with $100\%$ organic compost on the growth and yield characteristics of fall-cropping potato (Solanum tuberosum L. cv. Dejima) in Jeju. The treatments consisted of seven plots: 2-, 4-, 6-, 8-, and 10-ton $ha^{-1}$ EWC-treated plots, 1.2-ton $ha^{-1}$ complex fertilizer $(N-P_2O_5-K_2O,\;10-10-14)-for-potato$ (CEP)-treated plot as conventional practices, and a control plot. The plant heights were greater in the plots where EWC and CFP were applied than in the control plot. Tuber diameter, number of stems per plant, and chlorophyll level tended to increase in the plots where 8-10 tons $ha^{-1}$ of EWC were applied. The application of CFP and EWC showed an increment in the average tuber weight per plant, but there was minimal significant difference. The application of 8-10 tons $ha^{-1}$ of EWC resulted in an increase in the total tuber yield (21.61-21.87 tons $ha^{-1}$) as compared to the other plots. The highest yield of market able tubers was $69.8\%$ of the total yield from the 10-ton $ha^{-1}$ EWC-treated plot. Consequently, with regard to the growth and yield characteristics of fall-cropping potato, the effects of EWC application were more favorable than the effects of the application of a chemical fertilizer.

• Journal of Chest Surgery
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• 제47권2호
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• pp.124-128
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• 2014

Background: A closed pleural biopsy is commonly performed for diagnosing patients exhibiting pleural effusion if prior thoracentesis is not diagnostic. However, the diagnostic yield of such biopsies is unsatisfactory. Instead, a thoracoscopic pleural biopsy is more useful and less painful. Methods: We compared the diagnostic yield of needle thoracoscopic pleural biopsy performed under local anesthesia with that of closed pleural biopsy. Sixty-seven patients with pleural effusion were randomized into groups A and B. Group A patients were subjected to closed pleural biopsies, and group B patients were subjected to pleural biopsies performed using needle thoracoscopy under local anesthesia. Results: The diagnostic yields and complication rates of the two groups were compared. The diagnostic yield was 55.6% in group A and 93.5% in group B (p<0.05). Procedure-related complications developed in seven group A patients but not in any group B patients. Of the seven complications, five were pneumothorax and two were vasovagal syncope. Conclusion: Needle thoracoscopic pleural biopsy under local anesthesia is a simple and safe procedure that has a high diagnostic yield. This procedure is recommended as a useful diagnostic modality if prior thoracentesis is non-diagnostic.

• 한국지반공학회지:지반
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• 제5권1호
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• pp.7-18
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• 1989

암반에 지지된 선단지지맡뚝에 대한 연직재하시험시, 극한하중에 이르기까지 재하를 실시하는 것은 일반적으로 불가능하다. 이러한 경우 말뚝재하시험결과로부터 설계하중을 결정하기 위하여 봉복 윤중의 개념이 도입되어 오고 있다. 그러나, 이 강복초중을 결정하기가 용이하지 않은 경우가 많다. 본 논문에서는 우리나라 서해안과 남해안 지대 6개 현장에서 실시된 말뚝재하시험결과를 검토분 석하여 항복하중을 쉽게 결정할 수 있는 새로운 방법을 제안하였다. 이 방법에서 강복하대은 말뚝의 침하량을 대수눈금으로, 하중을 정규눈금으로 한 반대수응지상에 정리된 하중과 침하량 체선(P- log영상의 변곡점으로 정의되었다. 이 방법에 의한 강복연동보다 약간 많은 하중까지 재하시험을실 기하므로써, 말뚝재하시험의 비용과 시간을 절약할 수 있을 뿐만 아니라 안전한 작업조건도 마련할 수 있다. 이 강복하중은 하중과 침하량 거동의 탄성한계를 규정짓는 하중이 됨을 알 수 있었다. 25.4 mm침하시의 하중으로 결정되는 식한하동은 이 강복륜중의 1.i배에 해당하였으며 장기 및 단기 허 용하중은 각각 이 항복하중의 50%와 75%에 해당하였다. 또한 정역학적 지지력공식을 사용하여 허 용지지력을 구할 경우 안전율은 2.0~4.0으로 밝혀졌다.