• 한국작물학회지
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• 제43권4호
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• pp.264-268
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• 1998

The experiment was conducted to clarify irrigation requirement and percolation rate in rice paddy. The four rice cultural system of no-tin, till, transplanting, and direct seeding condition were treated in the lysimeter filled with sandy loam soil. The amounts of irrigation and soil percolation were measured daily, and irrigation requirement was estimated. The daily percolation was 19.5 l/$\textrm{m}^2$ in no-till direct seeding on flooded paddy surface, 17.4 l/$\textrm{m}^2$ in both of till-direct seeding on flooded surface and no-till transplanting, and 15.2 l/$\textrm{m}^2$ in transplanting plot. This is equivalent to 19.5, 17.4, and 15.2 mm per day, respectively. Highest irrigation requirement was 3,770 l/$\textrm{m}^2$ in no-till direct seeding plots. Others were 3,249, 2,577, and 2,321 l/$\textrm{m}^2$ in till-direct seeding, no-till transplanting and transplanting plot, respectively. The estimated irrigation requirement of no-till transplanting, till-direct seeding and no-till direct seeding was increased by 11, 37, and 59% compared to till-transplanting plot. Percolation rate of no-till transplanting, till direct seeding and no-till direct seeding was increased by 12%, 40%, and 66%, respectively compared to the till-transplanting plot. The percolation rate in paddy soil was increased greatly after reproductive stage of rice.

• 아시안잔디학회지
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• 제26권2호
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• pp.123-128
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• 2012

Kentucky bluegrass 는 경기장과 골프장의 Tee 나 Fairway 등에 가장 많이 사용이 되는 한지형잔디 초종중의 하나이다. 그러나 Kentucky bluegrass 는 뿌리층이 얕고 그늘에 약한 단점들이 있다. Kentucky bluegrass 의 가장 큰 단점중의 하나는 성장을 위해 수분이 많이 요구되는 초종이다. 올바른 수분관리는 잔디의 시각적 색감과 품질을 유지하기 위해 아주 중요한 요소중의 하나이다. 잔디의 성장을 위해 수분을 공급하는 관수 방법에는 light and frequent (LI) 적은양을 빈번하게 관수하는 방법과, deep and infrequent (DI) 많은양을 필요시에 공급하는 두가지의 방법이 있다. 본 실험은 Kentucky bluegrass 의 생육을 위한 관수빈도의 차이를 알아보기 위해 수행되었다. 실험을 위해 무관수, 매주 4회, 그리고 매주 1회의 3가지 관수방법이 사용되었다. 무관수 처리구의 경우 인위적인 관수는 수행되지 않았으며 Kentucky bluegrass 의 생육을 위해 수분공급은 강수량에 의해서만 이루어졌다. 본 실험결과 2011년 기상조건하에서 강우량에 의존한 무관수는 7,8 월에 최소수용품질을 나타내기 어렵다고 판단되며, 관수빈도에 따른 Kentucky bluegrass 생육의 차이는 나타나지 않는 것으로 나타났다.

• Current Research on Agriculture and Life Sciences
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• 제18권
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• pp.33-42
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• 2000

A field case study was performed to investigate the effect of shallow ponding in paddy field on irrigation water requirement of direct seeded rice. In addition, an economic analysis was made to see the effect of no-till direct seeded rice on cost reduction. A field study was performed at a 2.1ha paddy field in Kimjae city, Chonbuk province from 1991 to 1999. Various direct seeding methods such as dryland seeding, wetland seeding, and no-till wetland seeding were introduced. Then, cost reductions due to the direct seeding and no-till were calculated. In addition, to investigate the effect of shallow ponding on irrigation water requirement, field measurements such as irrigation water volume, drainage water volume, rainfall depth, and ponding depth, were made at a 40a plot within the same area in 1988 and 1990. The results of the shallow ponding study showed that the irrigation water depth, rainfall, and the drainage depth were 379mm, 458mm, and 448mm in 1988 growing season, and 274mm, 819mm, and 736mm in 1990, respectively. The shallow ponding irrigation method saved irrigation water by about 20% with higher yield compared with the traditional method. The economic analysis showed that won \640,000 per ha can be saved by direct seeding due to no nursery cost, and \1,220,000 per ha due to no-till and no nursery cost. The yields ranged 540 to 640 kg per 10a during the study period with an average of 590kg per 10a. If these cropping techniques with no-till direct seeding and shallow ponding depth for rice cropping prove to be advantageous with further study, they can be adopted for the most of the paddy fields in Korea.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.223-223
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• 2017

This study aimed to determine the effect of organic matter content and water condition in soil on yield, carbohydrate, and inulin contents of two varieties of Jerusalem artichoke. The plants were grown with high and low organic soil either under irrigation or no irrigation in a randomized complete block design (RCBD) with three replications. In result, the yield of Jerusalem artichoke was higher about 7 kg in soil with high organic matter than in soil with low organic matter, while it was higher about 11 kg under the irrigation than under no irrigation. The yield of white variety was higher about 9 kg than that of purple variety. Under the irrigation, a 12 kg and 9 kg of higher yields were observed in the soil with high and low organic matter content, respectively, than under no irrigation.

• Restorative Dentistry and Endodontics
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• 제18권2호
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• pp.377-386
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• 1993

The purpose of this study was to evaluate the disinfection efficacy of root canal irrigation method and irrigation solution in infected root canals. Access cavity were prepared in single-rooted extracted human teeth and each canals were prepared with step-back method and sterilized with ethylene oxide gas. Prepared teeth were experimentally inoculated in the canals for 30 minutes with four aerobes(Streptococcus mutans, Stapylococcus aures, Streptococcus sanguis, and E. coli) and two anaerobes(Streptoccus intermedius, and Clostrium perfringens). Normal saline, 3% $H_2O_2$, and 3% NaOCl were used as irrgation solutions. And root canals were irrigated with each irrigation solutions manually with disposible syringe or ultrasonic instument. (Apoza Uitrasonc, Taiwan). The irrigation effect on the eradication of S. aures and S. intermedius with normal saline was not similar between manual method and ultrasonic method. No significant differences were observed in the eradication of E. coli and C. perfringens among the irrigation solution and irrespective of the irrigation methods. In S. aurues and S. mutans, there was somewhat different eradication effect according to irrigation solutions, but there was no significant difference between manual method and ultrasonic methods. These results suggest that ultrasonic irrigation method with saline is more effective in some strains than manual irrigation.

• 한국유기농업학회지
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• 제23권4호
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• pp.781-796
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• 2015

시설채소 무경운 유기재배와 분할관수 효과를 구명하고자 시험을 수행한 결과 1회 전량 관수한 경운재배 토양의 수분함량은 30 cm 깊이까지 관수개시 후 급격하게 증가 후 다음 관수 직전까지 계속하여 감소되었다. 경운 토양의 수분함량 편차는 토양이 깊어질수록 감소되었다. 1회 전량 관수한 무경운 토양 표토와 지하 20 cm 깊이의 수분함량은 해가 뜨기 시작하면 증가되고 야간에는 감소되는 증발산에 의한 주기적인 일변화를 보였다. 그리고 2회 분할 관수한 경운 표토와 무경운 표토와 지하 20 cm 깊이까지의 수분함량은 증발산에 의한 주기적인 일변화를 나타내었다. 토양의 염류농도는 관수 후 증가되기 시작하여 다음 관수 직전까지 계속하여 감소되었으며, 토양이 깊어질수록 염류농도 증가 시간은 지연되었다. 무경운 표토의 염류농도 오전 11시부터 정오 12시 사이에 증가되기 시작하여 오후 2~6시경을 정점으로 1일 1회 증가와 감소되는 증발산작용에 의한 일변화를 보였다. 30 cm 깊이의 무경운 토양에서는 염류농도의 일변화가 측정되지 않았다. 토양수분 함량과 염류농도는 경운방법에 관계없이 정(+)의 상관관계를 나타내었다. 무경운 토양에서 재배된 고추의 생육은 경운 토양에서 재배된 고추에 비하여 생육이 억제되는 경향을 보였다. 경운방법에 관계없이 50%씩 2회 분할 관수한 토양에서 재배된 고추는 1회 전량관수에 비하여 주지의 길이와 경경 등 생육이 증가되는 경향을 보였다. 고추의 수확과수는 1회 전량관수에 비하여 2회 분할 관수가 경운과 무경운 처리에서 각각 49%와 47% 정도 현저하게 증가되었다. 고추 수량은 무경운 재배가 관행 경운재배에 비하여 8% 정도 증수되었다. 2회 분할관수의 고추 수량이 1회 전량관수에 비하여 수확과수의 증가로 경운 재배에서는 36%, 무경운 재배에서는 39% 정도 현저하게 증수되었다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.764-769
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• 2000

A new transplant production system that produces high quality plug seedlings of specific crop has been studied. It is a plant factory designed to produce massive amount of virus free seedlings. The design concept for building this plant factory is to realize maximum energy efficiency and minimum initial investment and running cost. The basic production strategy is the sitespecific management. In this case, the management of the growth of individual plantlet is considered. This requires highly automated and information intensive production system in a closed aseptic environment the sterilized specific crops. One of the key components of this sophisticated system is the irrigation system. The conditions that this irrigation system has to satisfy are: 1. to perform the site specific crop management in irrigation and 2. to meet the no waste standard. The objective of this study is to develop an irrigation scheduling that can implement the no waste standard.

• 한국환경과학회지
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• 제21권3호
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• pp.289-296
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• 2012

The purpose of this study was to identify the irrigation intervals and the amount of suitable growing substrate needed to achieve the desired shallow-extensive green roof system during a dry summer in Korea. In terms of treatment, three types (SL, $P_6P_2L_2$, $P_4P_4L_2$) with varying soil mixture ratios and two types (15 cm, 25 cm) with varying soil depths were created. The results have been analyzed after measuring growth and soil water contents. The difference of growth by treatment was significant in terms of green coverage, height, leaf width and photosynthesis. In measurement of chlorophyll content, no difference was detected when measured against soil depth. According to the growth measurement of Zoysia japonica with respect to differing soil mixture ratios in the 15 cm-deep treatment, a statistical difference was detected at the 0.05 significance level in photosynthesis. In case of green coverage, height, chlorophyll content and leaf width, no statistical significance was observed. In case of the 25 cm-deep treatment, a statistical significance was observed in height and photosynthesis. In terms of green coverage, chlorophyll content and leaf width, no statistical significance was detected. In comparisons of soil moisture tension and soil water contents, the irrigation interval and amount were 8 days and 14.9 L in the SL (15 cm) treatment, respectively. The irrigation interval showed for 10 days a 1.3-fold increase, and the irrigation amount was 27.4 L 1.8-fold more than SL (25 cm), respectively. For $P_6P_2L_2$ (15 cm) treatment, the irrigation interval and amount were 12 days and 20.7 L, respectively. However, an irrigation interval under $P_6P_2L_2$ (25 cm) was for 15 days 1.3 times longer than $P_6P_2L_2$ (15 cm), and an irrigation amount of 40 L was 1.9 times more than that under $P_6P_2L_2$ (15 cm). In $P_4P_4L_2$ (15 cm) treatment, it was indicated that the irrigation interval was 15 days, and the irrigation amount was 19.2 L. It was not needed to irrigate for 16 days under $P_4P_4L_2$ (25 cm) treatment during the dry summer and the longest no-rain periods. The irrigation interval and amount under $P_4P_4L_2$ were 1.8-fold and 1.3-fold, respectively, more than SL treatment as affected by soil mixture ratio. Comparatively $P_4P_4L_2$ had more 1.3-fold and 0.9-fold in irrigation interval and amount more than $P_6P_2L_2$. Therefore, it can be noted that different soil depth and soil mixture ratios had a significant effect on the irrigation interval and amount.

• 생물환경조절학회지
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• 제15권2호
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• pp.156-161
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• 2006

토마토 초장의 경우 심층수처리는 대조구에 비해 두상관수는 50%, 저면관수는 58% 감소하였고, 표층수 처리구에서는 두상관수는 49%, 저면관수는 56% 감소하였으며, NaCl 처리구에서는 두상관수는 47%, 저면관수는 57%감소하여 저면관수 처리방법이 도장억제에 더 효과적이었다. 지상부 생체중의 경우 두상관수보다 저면관수에서 더 감소하는 경향을 보였으나 뚜렷한 차이가 나타나지 않았다. 지하부 생체중 대조구에 비하여 두상관수는 38%정도 감소한 반면 저면관수는 49% 정도 감소하여, 저면관수에 의해 생육이 현저히 억제되는 결과를 보였다. 지상부와 지하부의 건물중은 생체중과 비슷한 경향을 나타냈다. 이와 같은 결과는 염에 의한 뿌리생육의 저하 때문인 것으로 판단된다. 경경은 대조구에 비해 감소하였지만 처리 방법 간에 뚜렷한 차이를 보이지는 않았다. T/R률에 비추어 보면 두상관수 처리에서 묘소질이 더 뛰어났으나, 묘의 충실도(compactness)는 처리구간 차이는 나타나지 않았다. 토마토의 경우 초장의 억제정도나 묘의 충실도에 비춰보아 저면관수 방법이 도장억제에 더 효과적이라 사료된다. 오이의 경우 처리 농도의 증가에 따라 초장, 생체중, 건물중, 경경, 엽면적이 감소하였다. 저면관수가 두상관수에 비해 도장억제 효과와, 생육억제가 좀 더 뚜렷이 나타나기는 하였으나 두 처리간의 유의적 차이는 나타나지 않았다.

• 한국토양비료학회지
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• 제43권1호
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• pp.68-74
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• 2010

담수상태의 토양이나 습지생태계에서 ${NO_3}^-$는 환원상태의 발달을 지연시키는 완충역할을 할 수 있다. 논토양에서 관개용수를 통하여 공급되는 ${NO_3}^-$가 Fe의 환원과 그에 따른 P의 가용화에 미치는 영향을 조사하였다. 관개용수중의 ${NO_3}^-$ 함량이 5 mg N $L^{-1}$ 수준일 경우 5 cm 깊이 토양에 도달하기 전에 대부분 탈질작용에 의해 제거되었으며, 5 cm 깊이 토양에서 일어나는 Fe의 환원과 P의 용출이 저해되었고 10 cm 깊이 토양의 환원현상에는 영향을 미치지 못하였다. ${NO_3}^-$ 함량이 10 mg N $L^{-1}$ 수준인 관개용수를 공급하였을 경우에는 10 cm 깊이 토양층까지 ${NO_3}^-$가 잔류 유입되었으며, Fe의 환원과 P의 용출을 현저히 억제하는 것으로 나타났다. 이상의 결과를 보면 관개용수를 통하여 ${NO_3}^-$를 포함한 질소가 과도하게 논토양으로 유입되면 질소과다현상을 유발할 뿐만 아니라 P의 가용화를 억제함으로써 인 결핍을 초래할 수도 있을 것이다.