• 아시안잔디학회지
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• 제1권1호
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• pp.18-29
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• 1987

This study was carried out to examine the effect of nitrogen application and clipping interval on the characteristics of several turf components of korean lawngrass for the basic data of lawn management. It was treated by Split plot design with three replications. The main plots were nitrogen levels with 0, 350, and 700kgN / ha, and the sub plots were clipping intervals with 10, 20, and 30 days The results obtained are summarized as follows ; 1. Increasing the rate of nitrogen fertilizer and frequent clipping increased tiller number of korean lawngrass and the maximum number of tillers obtained in October were recorded from 700kgN application and clipping treatment of 10 days interval. Meanwhile, treatment of 350kgN with 10 days clipping interval increased tillers much more than those of 700kgN with 20 and 30 days clipping intervals. 2. The average number of green leaves occurred during the growth period maximized by applying 700 kgN and clipping 10 days interval. 3. Increasing tiller numbers significantly decreased tops DM weight per tiller by clippng plants at interval of 10 and 20 days, irrespective of nitrogen applied, and with nil N, at the interval of 30 days. By applying 700kgN however, tops DM weight per tiller increased as the number of tillers increased consistently. 4. The highest tops DM weight was achieved from late August to early September by applying 350 and 700kgN. 5. During the growth period, nitrogen application increased unders(stolon+root) DM weight, and, at the same level of nitrogen applied, the increase in stolon DM weight enhanced by lengthening the clipping interval to 30 days. 6. Nitrogen efficiency to green leaves, stolon nodes and DM weight of root with high nitrogen was achieved as clipping interval was shortened.

• 한국토양비료학회지
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• 제47권3호
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• pp.147-154
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• 2014

Consecutive pepper cultivation in plastic film houses may lead to salt accumulation because pepper is considered a heavy nutrient feeder. For this reason, appropriate methods of fertilizer application should be established. Thus, we investigated the effect of different intervals of side-dressing N and K fertilizer applications on soil and red pepper in a plastic film house. All the amounts of recommended compost and phosphorus fertilizer were applied as basal dressing. Cultivars of the pepper plant were Cheon-Ha-Dae-Se (CHDS) and NW-BiGaLim (NW-BGL). Nitrogen and potassium fertilizers were treated as side-dressing at different intervals, 22 times in every 10 days, 15 times in every 15 days, and 11 times in every 20 days. Soil pH decreased with decreasing the intervals of side-dressing applications, whereas electrical conductivity (EC) declined with the increasing fertilizer application intervals. In particular, EC value decreased by up to 75% with CHDS cultivar in the plot of 20 day-interval and with NW-BGL cultivar in the plot of 15 day-interval. The concentrations of available phosphorus in the soils increased with increasing the interval. The concentration of exchangeable $K^+$ increased but exchangeable $Ca^{2+}$ and $Mg^{2+}$ decreased in all the plots, except in the control plot. The concentrations of nitrogen and phosphorus in leaves of the pepper plants were lowest in the control plot. Potassium concentrations in the pepper leaves were high in the control plot and in the plots of CHDS with 10 day-interval and NW-BGL with 15 day-interval. Red pepper productivity was high in the plots of 10- and 15 day-intervals for CHDS cultivar and 15- and 20 day-intervals for NW-BGL cultivar. Therefore, the 15 day-interval of side-dressing N and K applications was considered as an appropriate method for cultivating pepper plants and protecting soil in plastic film houses.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.984-987
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• 1996

We consider a feedback control system including interval plant where uncertain parameters expressed in the hyperrectangular box X. Here we define the maximum value of the integral of the error(ISE) as the worst performance index(WPI) due to the plant parameter uncertainty. Suppose that the closed loop system retains robust stability and it belongs to type I. Then we show that the WPI occurs only on the exposed edges of Q. In particular, it is also shown that if ISE is a convex function relative to X, the WPI is attained at one of vertices of X. Some examples are given.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1294-1300
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• 2008

In the current railway industry in Korea, a lot of researches and studies have been progressed to establish RAMS process and construction of RCM system in accordance with international standards. On the point of view of applying the RCM to the railway system, many problems (i.e., reliability of the existing field data, the lack and incorrectness of failure information, etc) are described. To solve these problems, it is need to study and effort the RCM, practically. In this paper, lots of problems and solutions for methods determining the preventive maintenance interval of application of the RCM will be described. To do this, the method using the theory of RBI (Reliability Based Inspection) which is applied to the existing chemical plants and power plants is described. From this study, it is expected that in this situation that the quantitative data is not enough, the results that an analyst quantifies the qualitative factors and/or items will be a good reference that can effectively approach, on the side of determination about each maintenance task and inspection interval.

• Journal of Ginseng Research
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• 제22권3호
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• pp.161-167
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• 1998

American ginseng plants (Panax quinquefolium L.) of various ages were harvested every two weeks during each of three growing seasons and dry matter yield of components and root respiration determined. Shoot dry weight was about 0.5 g, 2.5 g and 4 g for 2, 3 and 4-year-old plants, respectively and fruit dry weight was as much as 50% of this in 3- and 4-year-.old plants. Root dry weight decrease by 30~50% as shoots emerged and at the end of the season was about 2 g, 3.5 g and 5 g in 2, 3, 4 and 5-year-old plants, respectively. Shoot and root dry weight were linearly related with an approximate 1:2 ratio. Root respiration rate at 2$0^{\circ}C$ in the dark was about 5 $\mu\textrm{g}$ CO2 g-1 DW(dry weight) min-1 in the early season, then doubled within 50 days as shoots emerged, and thereafter declined over the season to 2~5 $\mu\textrm{g}$ CO2 g-1 DW min-1. The Q10 for dark respiration over the interval from 10 to 2$0^{\circ}C$ was 1.58. Root respiration rate and shoot growth rate was positively linearly related in all ages of plants. Key words: Dry weight, partitioning.

• 인간식물환경학회지
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• 제23권2호
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• pp.179-189
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• 2020

In order to increase the indoor air purification effect of plants, plants need to be placed on 5-10% of indoor spaces. To increase the density and utilization of plants in indoor spaces, studies on bio-wall, a vertical green wall system, have been recently conducted. The purpose of this study was to investigate the growth characteristics of 7 indoor plants introduced to the system and their rooting zones at different irrigation cycles. This study was conducted to investigate a proper irrigation cycle for the continuous maintenance of bio-wall systems. The conditions of their growth environment were maintained as follows: light intensity, 20-50 μmol·m^-2·s^-1 PPFD; and temperature, 20 - 25℃. For fertilization, Hyponex diluted with water at the ratio of 1:1,000 was supplied to plants. Irrigation was treated at intervals of 1, 3, 5, and 7 days for 1 hour at a time. As a result, there was no significant difference in the growth of plants between different irrigation cycles. Dieffenbachia 'Marianne' showed a significant decrease in the number of leaves at the irrigation cycle of 7 days. In addition, the chlorophyll content was relatively low at the irrigation cycle of 7 days. In terms of the color of leaves, a decrease in L value and b value and an increase in a value were observed, resulting in changes in brightness and color. Ardisia pusilla 'Variegata' showed a slightly higher photosynthetic activity and stomatal conductance when it was watered every day and once per 5 days, while Epipremnum aureum showed a relatively higher photosynthetic activity and stomatal conductance at the irrigation cycle of 3 days. In the case of root activity, it was found that the longer irrigation cycle, the higher root activity compared to daily irrigation. The development of roots of Peperomia clusiifolia was promoted by watering at long intervals. However, in the case of Aglaonema 'Siam-Aurora', the total number of roots decreased at the interval of 7 days. In conclusion, a proper irrigation cycle for the sustainable maintenance of vertical bio-wall systems seems to be 3 days.

• 식물분류학회지
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• 제44권3호
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• pp.208-221
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• 2014

홀로세 기후최적기는 후빙기 동안에 가장 온난했던 시기로서 현재의 기온보다 $1-4^{\circ}C$ 높았다. 남방계식물들은 홀로세 기후최적기에 북쪽 또는 해발고도가 높은 지역으로 분포가 확장되었을 것으로 추정된다. 본 연구에서는 제주도, 남해안아구 또는 남부아구가 주 분포역이고 주 분포의 북방한계선에서 100 km이상 격리된 잔존집단이 존재하는 근거리 산포형의 남방계식물을 '기후최적기 잔존종'으로 규정하였다. 식물상 자료, 표본정보, 생태학적 연구 자료와 현장조사 자료를 분석하여 기후최적기 잔존종을 선정하고 이들의 분포도를 작성하였다. 화분층위학과 고생태학적 연구 자료를 근거하여 본 가설을 평가하였다. 그 결과 히어리, 소사나무, 노각나무와 같은 홀로세 기후최적기 잔존종은 기후최적기 동안에 북쪽으로 이주하였을 것으로 판단된다.

• 한국초지조사료학회지
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• 제15권1호
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• pp.30-36
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• 1995

Pasture composed of about 30% botanical composition of white clover (Trijolium repem L.) is desirable in its productivity and quality. To get information on maintaining its productivity in the pasture, the experiment was canied out to determine the effect of infrequent, frequent defoliation or their alternation on change of its harvest yield and growth. Individual plants of Regal, Louisiana S-1, Grasslands Huia and Aberystwyth S184 were grown in 22cm plastic pot containing a 2 : 1 : 1 soil : sand : Peat moss mixture for 27 days after transplanting 50day seedlings raised on 3cm pots, and then all their fully expanded leaves are removed. Defoliation treatments were forced every 1 (CC, frequent), 4 week (RR, infrequent) or their alternations (CR, RC) after 8 weeks from the removal. To analyze the treatment effects, plants were sampled on 0 (the removal day), 4, 8, 12 and 16 weeks after the removal and seperated to leaves, petioles, stolons and roots. Each harvest yield of infrequent defoliation (RR) was higher than that of frequent defoliation (CC). Their alternations (RC, CR), however, forced fluctuation of the yield according to defoliation interval. Fraction weights from their altemations showed intermediate ones of infrequent and Frequent defoliation whose weights did the similar result to their harvest yields. Fraction and total dry weights per plant, shoot/root ratio were changed by relative span of defoliation interval, which resulted from the weights of leaves and petioles, removed parts. Root and total dry weight per plant of Regal were greater than the other cultivm in infrequent defoliation interval regardless of continuous or alternations. Productivity of white clover in pasture, therefore, can be controlled by alternation of infrequent and frequent defoliation or reverse.

• 한국작물학회지
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• 제40권1호
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• pp.26-32
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• 1995

White clover는 많은 장점에도 불구하고 계속방목에 대한 적응력이 낮아 존속연한이 짧은 것이 결점이다. 따라서 본 시험은 white clover 혼파초지관이에 필요한 정보를 제공하기 위하여 예취주기의 장단(7일, 14일, 28일)이 28일의 재생기간 동안 잎의 크기가 다른 white clover 품종(Osceola, Huia, S184)의 질소고정, 각부위(잎과 엽병, 포복경 및 뿌리)별 total nonstructural carbohyd-rate(TNC) 및 질소의 분배에 미치는 영향을 조사하기 위하여 온실에서 pot 시험으로 실시한 바 그 결과를 요약하면 다음과 같다. 1. TNC 함량은 포복경과 뿌리에서 예취주기를 7일에서 28일로 늘임으로써 증가하였고 대엽종인 Osceola에서 가장 높은 함량을 보인 반면, 중엽종인 Huia와 소엽종인 5184은 각부위간분배가 다른 것으로 나타났다. 2. 질소함양은 전부위에서 이상의 포복경과 뿌리의 TNC 함량과 유사한 반응을 보였다. 3. TNC 함량은 뿌리보다는 잎과 엽병 또는 포복경에서 많은 반면, 질소함량은 엽병, 뿌리, 포복경의 순으로 감소하였다. 4. 예취로 인하여 전부위의 TNC 및 질소 함량은 감소하였으나, 재생기간이 길어짐으로써 증가하는 경향이었다. 또한 예취주기에 따라 재생기간 중 각부위간 TNC 및 질소 분배에는 차이가 있는 것으로 조사되었다. 5. 질소고정은 예취주기가 7일에서 28일로 증가함으로써 증가하고 대엽종일수록 큰 것으로 나타났으며, 예취 3일후까지는 감소하다가 그 이후에는 증가하였다.

• 한국작물학회지
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• 제39권3호
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• pp.245-255
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• 1994

White clover는 많은 장점에도 불구하고 계속방목에 대한 적응력이 낮아 존속연한이 짧은 것이 결점이다. 따라서 본 시험은 white clover 혼파초지관리에 필요한 정보를 제공하기 위하여 예취주기의 장단(7일, 14일, 28일)이 28일의 재생기간동안 잎의 크기가 다른 white clover 품종들(Osceola, Huia, S184)의 수량과 재생에 미치는 영향을 조사하기 위하여 온실에서 pot 시험으로 실시한 바 그 결과를 요약하면 다음과 같다. 1. 28일의 처리기간중 수확 건물중은 대엽종 Osceola가 타품종에 비하여 많았고, 예취주기를 28일에서 7일로 줄임으로써 현저히 감소하였다. 2. 재생기간중 개체당 건물중은 주로 잎과 엽병의 증가에 기인하였고 예취 후 14일부터 대엽종 Osceola가 타품종에 비하여 많았다. 3. 개체당 엽면적과 복엽당 엽면적은 28일의 재생 기간동안 꾸준히 증가하였으나 예취를 28일에서 7일로 줄임으로써 현저히 감소하였다. 대엽종 Osceola의 개체당 엽면적과 복엽당 엽면적은 타품종에 비하여 많았다고 하나, 예취 후 28일의 개체당 엽면적에는 품종간 차이가 없는 것으로 측정되었다. 4. 예취주기를 짧게 할수록 엽수와 엽병장이 감소하였으며 예취 후 14일부터 타품종에 비하여 소엽종 S184가 많은 엽수를, 대엽종 Osceola가 긴 엽병을 확보하고 있는 것으로 조사되었다. 5. 개체당 포복경장과 분지경수는 재생기간동안 급격히 증가한 반면 소엽형 S184에서 가장 길고 많았으며 예취주기를 28일에서 7일로 줄임으로써 현저히 감소하였다.