• 한국지역사회생활과학회지
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• 제19권3호
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• pp.365-371
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• 2008

This study was conducted to determine the potent physiological activity of traditional wild tea ("Don tea"; coin-shaped tea) as affected by different harvesting times, aging periods and extracting temperatures, No difference in anti-oxidative activities in the harvesting time and extracting temperature of tea leaves was observed. However, short aging periods of Don tea showed high ABTS {2-2-azonobis (3-ethylbenzothiazolin-6-sulphonic acid)} activity, ranging from 71.52 to 79.96%. DPPH (${\alpha},\;{\alpha}-diphenyl-{\beta}-picryl-hydrazyl$) radical scavenging activity of Don tea was 71.10 to 91.40%. Especially, longer aging period and an extracting temperature of $100^{\circ}C$ showed higher DPPH radical scavenging activity. With longer aging periods and an extraction at $90^{\circ}C$, nitrite radical scavenging activity of Don tea ranged from 74.04 to 94.92%. On the other hand, angiotensin 1-converting enzyme (ACE) inhibition activity of Don tea was 59.77-81.97%. It showed higher activity when harvested in June and August, aged for longer periods, and extracted at $100^{\circ}C$. These results suggested Korean traditional Don tea exhibited the highest physiological activity when aged over 8 months.

• 한국작물학회지
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• 제8권1호
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• pp.83-89
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• 1970

각종 재배조건 및 저장기간이 고구마 전분함량에 미치는 영향을 구명코저 신미 품종을 공시하여 삽식기별 수수기별 시비량별 토성별 저장기간별로 구분 시험을 실시하였든바 요약하면 다음과 같다. 1. 5월 15일 삽식에 비하여 만식일수록 괴근수량 및 전분함랴은 감소되었고 특히 6월 5일 이후의 삽식에서 급격히 감소되었으며 괴근수량의 감소정도에 비하여 전분함량의 감소정도는 더욱 심하였다. 2. 10월 5일 적기수확에 비하여 조기수확일수록 괴근수량 및 전분함량은 감소 경향이였고 8월 25일 이전 조기수확은 괴근수량 37~45% 전분함량 5~7%의 감소를 보였다. 3. 시비량에 따라서 전분함량은 차이가 많았으며 대체로 3요소를 균형시비하는 경우 전분함량이 높은 경향이었고 가리질비료를 다용하거나 인산질비료를 시용하지 않은 경우 낮은 경향이였다. 한편 괴근수량에는 $K_20$O>$P_20_5$>N의 순으로 효과가 높았다. 4. 토성에 있어서는 모래나 자갈이 많이 함유되어 있는 토양에서부터 경직토로 갈수록 전분함량은 낮았으나 10a당 전분수량은 조사토 및 식양토에서 높았다. 5. 저장기간중 전분함량은 수량직후에 가장 높고 저장일수가 경과함에 따라 감소하였으나 수확후 10일에서 급격히 감소되었고 그 후의 감소는 근소하였다.

• 한국초지조사료학회지
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• 제9권3호
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• pp.153-157
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• 1989

This experiment was carried out to investigate the effects of the first harvesting times and regrowth periods after the fist harvest on grass regrowth, dry matter (DM) yield and botanical composition in pasture mixtures during 1987 and 1988. For the test, a split plot design with 3 replications was treated with 3 different first harvesting times (vegetative, stem elongation and heading stage) and 3 different regrowth periods (20, 30 and 40 days) after first harvest. Although the total DM yield of grasses was decreased slightly with earlier cutting, the regrowth DM yield and the regrowth plant height was increased significantly with earlier cutting (p < 0.05). Also, the 30 days of regrowth periods was contributed greatly to the regrowth and the DM yield. The percentage of legumes Tmainly red clover) in botanical composition was increased with later initial harvest anrl longer regrowth period after first harvest. Based on the results, it is suggested that good grass regrowth and seasonal distribution could be achieved by the earlier harvest at fist and the regrowth period of 30 days after first harvest in spring.

• 한국잠사곤충학회지
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• 제31권1호
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• pp.12-19
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• 1989

추기 된서리로 인한 자연낙엽에 관계없이 상묘를 굴취할 수 있도록 하기 위하여 1985년부터 2년간 전국 각도 9개 지역에서 9월 30일부터 11월 20일까지 10일 간격으로 6회에 걸쳐 굴취하여 묘질을 분석한 결과 다음과 같았다. 1. 묘목의 굵기는 10월 30일까지 다소의 증가를 보였다. 2. 조기굴취는 그루당 새순의 수와 길이를 떨어뜨렸으며, 10월 30일 굴취구에서 생육이 가장 양호하였다. 3. 10월 20일 이후는 자연낙엽에 관계없이 굴취하여도 활착율과 생육에 영향을 주지 않았다. 4. 굴취시기를 늦을수록 체내에 전실소와 P함량이 증가되는 반면 K는 감소하였으며 Ca는 일정하지 않았다. 5. 전실소, P, Ca 등은 뿌리껍질에서 보다 줄기껍질에 함량이 높았으며 K는 일정하지 않았다.

• 한국의류학회지
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• 제32권8호
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• pp.1286-1298
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• 2008

This study was attempted to examine the indigo dyeing technique in the latter Joseon Dynasty, and to find diachronic specifics in the indigo dyeing method from 17C to 19C. The results are as follows: First, There were 2 kinds of indigo species-Yoram(Polygonum tinctorium Lour.) and Sungram(Isatis tinctoria L.)-in the latter Joseon Dynasty. Dangram was preferred in particular among Yoram species because of its high dyeing efficiency. Sungram was mainly used for making Jeon(indigo sediment). Second, Yoram cultivation took the following order: Sowing in April${\rightarrow}$planting out in June${\rightarrow}$harvesting leaves in August${\rightarrow}$collecting seeds in September. Sungram had more harvesting times and wider harvesting period than Yoram. Third, all indigo dyeing methods were grouped into two categories, one was temporary dyeing method, the other was permanent dyeing method. Mixture dyeing of the boiled and the raw, raw leaves dyeing, and fermentation dyeing belonged to the temporary dyeing. Jeon dyeing and Gaeogi dyeing belonged to the permanent dyeing. Finally, diachronic specifics from 17C to 19C were as follows: Decline in the mixture dyeing of the boiled and the raw, development in the raw leaves dyeing, continuance of the fermentation dyeing, and naturalization of Jeon dyeing technique.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2018년도 학술발표회
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• pp.485-485
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• 2018

Rainwater harvesting system (RWH) can provide a relief for the household and farmers especially in areas with intense water scarcity during the long lull of rainy season. However, much attention has not been given to this alternative water source in Nigeria. This paper estimates the per capita water demand for 1,950 inhabitants and rainwater potential in Ojonbodu Estate, Oyo State, Nigeria, using data from detailed questionnaires, water consumption calculator software, and 20-year rainfall data. The potential rainwater estimation was based on amount of precipitation, size of catchment and runoff coefficient. Consequently, using estimated values of $39420m^3$ and $6.5114{\times}10^7m^3$ for per capita consumption and potential rainwater respectively, the rainwater harvesting system was designed for rainwater collection, and storage. The harvested rainwater was $450, 000m^3$ with collection efficiency of 69.16 %, which exceeded the household water consumption requirement. Thus, the harvested rainwater was able to meet the estimated water demand of the Ojonbodu Estate households during the period of water scarcity.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.386-389
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• 2013

Under climate change and urbanization, rainwater harvesting (RWH) systems are emerging as an alternative source of water supply because of growing concern about water sustainability. RWH systems can satisfy the various watering needs and provide the environmental benefits of lessening the damages from flood, drought, and runoff. The economic success of a RWH system is vitally concerned with the determination of the design capacity of storage tank to be built in the system. The design capacity is determined by the factors of average annual rainfall, period of water scarcity, and water price during the whole life-cycles. Despite the high uncertainties inherent in these factors, the current engineering design of RWH system construction often assumes that storage tanks should be built all at once. This assumption implicitly ignores the managerial flexibility in responds to the future as new information comes out-the right to build storage tanks stage by stage depending on the evolution of demand. This study evaluates the value of a multistage storage tank construction using a real option approach. A case study involving a typical RWH system construction in Jeonju, the Republic of Korea is conducted. The managerial flexibility obtained from the real option perspective allows engineers to develop investment strategies to better cope with the issue of water sustainability.

• 한국환경과학회지
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• 제24권12호
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• pp.1681-1689
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• 2015

This study was conducted to investigate days after anthesis (DAA) and fruit after-ripening period (FAP) for seed-harvesting of high quality watermelon seeds. Fruit weight and number of seed per fruit increased according to DAA, while those did not significant about FAP. Ratio of cotyledon at whole seed was higher about 2 to 4% compared to seed coat irrespective of DAA and FAP. Germinability of watermelon was not a significant effect by DAA, however, it had differences by FAP. Percent of germination (PB) was below 50%, when 30 days maturated fruits after anthesis was omitted ripening, while PB was increased to 92% by ripening. In addition, seeds at DAA 40 and FAP 20 were higher general seedling vigors (hypocotyl length, diameter etc.) in BP test. Results indicated that considering seed productivity, it had maximized seed viability at DAA 40 and FAP 20.

• 상하수도학회지
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• 제27권5호
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• pp.621-629
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• 2013

Since algae had been issued an environmental problem, water blooms, deepened due to increase of retention water basin in Korea as well as a biomass resource for producing biofuel, this study conducted a series of experiments for Spirulina platensis using the flotation process with micro-bubble. To elevate utilization of collected-algae, this study focused on omitting or minimizing coagulant's doses as changing a cultivation period and condition affected on physical property change of algae. Two coagulants, PAC and Chitosan, were used to test the collecting rate of algae and the result found no difference between two rates. For flotation experiments without adding the coagulant, dried algae weight (passing 14 days after cultivation for 20 days) detected high separation efficiency 98.2 % and it (passing 7 days after long-term cultivation for 28 days) presented good separation efficiency 91.9 %. Chlorophyll's separation efficiency showed a similar tendency with the case of the dried algae weight. In endogeny conditions, a light source and a carbon source were not considerably affected on the flotation separation efficiency. Thus, this study confirms that algae biomass may be collected without the coagulant during the endogeny condition period after enough cultivation time, 3 weeks.

• 한국유기농업학회지
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• 제28권4호
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• pp.615-626
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• 2020

하계사료작물로 케나프를 재배할 시에 유기 및 화학비료의 질소공급원과 수확시기를 달리하였을 때 케나프의 생산성과 양질의 조사료를 얻기 위해 적정 질소시용수준과 수확시기를 구명하고자 실시되었다. 질소공급원에 따른 케나프의 건물수량은 화학비료 처리 구가 다소 높았지만, 유기질비료를 ha 당 200~250 kg의 수준에서는 화학비료 처리 구와 유의한 차이가 인정되지 않았고 사료가치 특히 조단백질과 TDN 함량은 오히려 유기질비료 처리 구에서 유의하게 높게 나타나(p<0.05), 반추동물에게 양질의 조사료 공급원으로 이용하고자 케나프가 재배된다면 유기질비료가 화학비료를 대체할 수 있음을 시사하였다. 한편 수확시기에 따른 건물수량은 100일째가 다른 수확시기보다 유의하게 높았지만 100~110일 수확시기가 수량구성요인 중 잎의 비율이 줄기보다도 높았고 사료가치 중 조단백질과 TDN 함량이 다른 수확시기보다 높게 나타났으며 ADF와 NDF 함량은 크게 감소하였다(p<0.05). 본 연구의 결과 특히 건물수량과 사료가치를 비교해 볼 때 적절한 질소공급원으로 유기질비료를 시용 시에는 ha당 200~250 kg 정도가 적절하고 수확시기는 100~110일이 적합하다고 사료된다.