• 한국환경과학회지
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• 제33권6호
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• pp.383-402
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• 2024

Variations in lettuce growth and quality were observed depending on the type of artificial light source. The RGB LED treatment resulted in thick leaf development, leading to higher fresh weight, dry weight, and relative growth rates. Two cultivars, "Tomalin" and "seonpunggold," exhibited increased anthocyanin content and dark red leaf color under conditions of RGB LED treatment. Additionally, they exhibited high chlorophyll content under conditions of RGB LED and RGBFR LED treatments. Particularly, under Red LED treatment, the plants showed elongated leaves with narrow widths, resulting in a higher leaf shape index and a tendency towards leaf curling. Therefore, RGB LED lighting which appropriately blends red, blue, and green lights, is more effective than single lighr sources at improving lettuce growth and quality.

• 한국환경복원기술학회지
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• 제17권3호
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• pp.53-63
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• 2014

This study was carried out to investigate the growth responses of medicinal plants such as Glehnia littoralis, Cryptotaenia japonica, Angelica gigas, Reynoutria japonica, Saururus chinensis, Houttuynia cordata, Ligularia fischeri, and Aralia cordata under 70%-shading and full sunlight conditions on a rooftop condition using artificial soil as a growth media. Glehnia littoralis, Cryptotaenia japonica, Ligularia fischeri, Saururus chinensis, and Houttuynia cordata showed better growth on plant height, leaf length, leaf width, petiole length and leaf number under full sunlight conditions on a rooftop condition. Cryptotaenia japonica and Houttuynia cordata had high value of Hunter's a (red-green) under full sunlight, while had lower value of L(lightness) and b(blue-yellow) than those of 70% shading condition. As an index of plant stress response, Glehnia littoralis, Reynoutria japonica, Houttuynia cordata, Ligularia fischeri showed Fv/Fm values 0.79~0.84 under full sunlight in August, indicating low stress on plant growth. Therefore they seemed to be suitable medicinal plats for rooftop conditions. Ligularia fischeri and Reynoutria japonica showed better growth under 70% shading treatment in August, while showed high growth response under full sunlight conditions in September. The 70% shading treatment was effective for the growth of Angelica gigas, Reynoutria japonica, and Aralia cordata. Angelica gigas and Reynoutria japonica, however, showed better plant growth under full sunlight during summer. The results showed that Glehnia littoralis, Cryptotaenia japonica, Ligularia fischeri, Saururus chinensis, and Houttuynia cordat seemed to be suitable medicinal plants for rooftop garden where there is a full sunlight condition.

• 한국작물학회지
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• 제26권4호
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• pp.350-356
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• 1981

본 실험은 묘상용 Vinyl pot의 크기와 Vinyl pot당 육묘주수를 달리하여 향끽미종 잎담배인 소향으로 Vinyl pot당 육묘가능주수의 구명과 생육비절멸방안을 모색코자 실시한 결과를 요약하면 다음과 같다. 1. Vinyl pot가 클수록 이식묘의 주당 건물중, 변이계수 및 건물율은 증가하였으나 T/R율, 경쟁지수및 단위생산성은 감소하였다. 2. Pot당 육묘주수가 많을수록 변이계수, 경쟁지수 및 단위생산성은 증가하였으나 주당 건물중은 감소하였다. 3. 자상성약구와 가식구는 모두 4cm pot에서 3주, 5cm pot에서 5주까지 육묘가 가능하였고 자상성약육묘보다 가식육묘가 유리하였다. 4. 5cm pot당 5주씩 육묘하여 대조구(3.5cm pot에 1주 육묘)에 비하여 묘상면적 및 묘상자재를 60.9%, 이식노동력을 36.3% 절감되었다.

• Journal of Biosystems Engineering
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• 제36권5호
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• pp.348-354
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• 2011

Various crop spacing methods have been implemented so far for the greenhouse and plant factory applications. However, there is no generally accepted parameter for evaluation of plant spacing efficiency in plant production system. In this study, 'Planted Area Index' (PAI) of a spacing method is defined as the ratio of the planted area in the field to required planted area using the spacing method when no transplanting operation is assumed. Three common types of spacing methods for plane placement of the plants were modeled mathematically. For calculating the planted area, an optimal growth radius function (R(t)) is needed. Function of the days after transplanting stage gives a radius of an optimal circle area for the living plants. A computer simulation was developed to calculate the PAI, based on three crop spacing methods and four optimal growth radius functions. In general, the 1-D zigzag spacing showed the best PAI. Moreover, it gives an example on how to apply the PAI for the design.

• 한국안전학회지
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• 제35권5호
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• pp.22-29
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• 2020

In this study, combustion and smoke release characteristics of a non-class 1E cable for nuclear power plants were investigated according to aging period. The aging was reproduced through an accelerated aging method for interval of 10 years :10, 20, 30 and 40 year, which was applied the Arrhenius equation. The cable was subjected to accelerated aging. In order to understand combustion and smoke release characteristics, the cone calorimeter test was performed according to the standard code of KS F ISO 5660-1. Heat release rate, mass loss rate, average rate of heat emission and smoke production rate were examined through cone calorimeter test. Fire performance index, fire growth index and smoke factor were derived from test results for the comparison of quantitative fire risk. When comparing the fire performance index and the fire growth index, the early fire risk tends to decrease as aging progresses, which might be attributed from the fact that the volatile substances of cables were evaporated. However, when comparing the heat release rate, average rate of heat emission and mass loss rate, which represent the mid and late periods of the fire risk, the values of accelerated aging cables were much higher than those of non-aged cable, which signifies the unstable formation of the char layer resulted in the change in the performance of flame retardants. In addition, the results from the smoke characteristics show that the accelerated aging cables were lager than the non-aged cables in terms of overall fire risk. These results can be used as baseline data when assessing fire risk of cables and establishing fire safety code for nuclear power plants.

• 한국양식학회지
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• 제7권2호
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• pp.77-87
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• 1994

전복을 육상수조에서 사육하기 위한 먹이 개발을 위하여 육상식물 및 배합사료를 공급하여 대조구인 미역과의 성장도, 생존율 및 먹이효과에 대하여 조사한 결과 1. 배합사료, 미역, 육상식물의 순으로 성장이 빨랐으며 생존율은 큰 차이가 없었다 2. 일간섭식률은 미역과 육상식물이 비슷하였고 배합사료는 이 들의 $30\%$ 수준이었다. 사료전환효율은 미역과 육상식물에 비해 배합사료가 월등히 높았으며 치패 크기가 작을수록 높았다. 3. EFA index, ${{\sum}n9/(20:4n6+20:5n3+22:6n3}$는 건미역이 1.26, 배합사요가 3.64로서 양호 값을 나타냈으나, 깻잎의 경우 127.00으로 나타나 참전복에 유효한 지방산이 거의 없는 것으로 나타났다. 4. 전복 육상수조에서의 사육을 위한 여름철 대체 먹이로는 육상식물보다는 배합안료가 효과적이었다.

• 한국환경복원기술학회지
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• 제8권5호
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• pp.47-55
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• 2005

This study was conducted to suggest revegetation character for environment factor of slope. Field test carried out for the man-made slope with three types(0.5cm no net, 3.0cm no net, 3.0cm net) revegetation methods in Hwaseong. Test revegetation plants were Festuca arundinacea, Lolium perenne, Lespedeza cyrtobotrya and Indigofera pseudo-tinctoria M. The result of this study can be summarized as follows; 1. The soil hardness, the soil acidity, and the soil humidity of three types(0.5cm no net, 3.0cm no net, 3.0cm net) revegetation methods were at a suitable value for plants growth. 2. All plant growth index(seedling number, ground coverage, plant height, plant weight, etc) of south slope were better than north slope. But plant growth index of net plots were similar to no net plots. 3. For washout investigation, washout quantity of north slope was plentifully measured from south slope, and 1 amount of rainfall will be big was visible appears plentifully.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.181-181
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• 2017

Global warming and climate change have been one of the most important problems last 2 decades. Global warming is known to cause abnormal climate and influence ecology, food production and human health. According to climate change model global warming is causing expansion of drought and increase of evaporation. Therefore, securing water in agriculture has been an important issue for crop cultivation. As potato is susceptible to drought, water shortage generally results in decrease of yield and decrease of biomass. In this research, we investigated characteristics of inorganic nutrient absorption and growth of plants grown under drought condition. Plants were sampled in sites of Cheong-ju and Gangneung, where the severity of drought stress were different. During the growth period in Gangneung, total rainfall in 2016 decreased by 50% compared with those in last 5 years average. Especially, there was almost no rain in tuber enlargement period (from mid-May to mid-June). On the other hand, the total rainfall in of Cheong-ju was is similar to those in last 5 years average. Inorganic components including K, Ca and Mg and plant growth factors such as plant length, stem length, leaf area index and plant biomass were investigated. Tuber yields in both areas were investigated at harvest. Growth period of plants was is longer in Cheong-ju than that in Gangneung. Contents of all inorganic components were higher in plants grown in Cheong-ju than in Gangneung. The results were attributed to higher production of plant biomass in Cheong-ju. Considering the results, severe drought stress conditions in Gangneung accelerated plant aging and resulted in low plant growth. Although total yield was greatly reduced under drought stress the rate of commercial yield was is not significantly different with non-drought conditions.

• 농업과학연구
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• 제42권4호
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• pp.293-297
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• 2015

This study was conducted to evaluate the influence of feeding leaf positions on the growth, net formation of fruits, and occurrence of leaf yellowing symptoms (LYS) in muskmelon plants. Plants having five or ten more leaves above the fruit-bearing node produced the greater biomass than those of plants having equal or five less leaves above the fruit-bearing node. The number of leaves above the fruit-bearing node also influenced on the occurrence of LYS. The number of plants with LYS decreased as the number of leaves borne on the nodes above the fruit-bearing node increased. The LYS infected ratio of BL-5 treatment were the greatest, while fruit weight of BL+5 treatment were the greatest among all the tested treatments. In addition, the net formation of BL-5 treatment showed the poorest. Results indicated that maintaining the higher number of leaves over the fruit-bearing node might be feasible the practical method for coping physiological damages from yellowing symptoms.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.383-392
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• 1993

Identification of rice paddy fields and estimation of their areas from the images taken by LANDSAT-5/TM were attempted. The results were verified by aerial photographs and also by ground observations. Changes of the spectral characteristics of rice plants were measured with a portable spectroradiometer during the growth period. Analyzing these characteristics, an index was developed for evaluating the growth and the yield of rice . Applying the index to the data observed by LANDSAT-5.TM on Sep. 26, 1986, Oct .20, 1989 and Sep, 21, 1990, it was confirmed that the estimated derived from the index agreed with actual values. The results well demonstrated its feasibility for evaluating the yield of rice by a satellite like LANDSAT-5/TM.