• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.162-170
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• 2000

This study quantified the effects of urban greenspace on microclimate amelioration and atmospheric $CO_2$ reduction for several residential districts selected in Korea and Japan. The study also explored fire obstruction by urban trees to develop systematic planting guidelines. Transpiration by a Zelkova serrata tree (diameter at breast height: 15 cm) in a day of August equaled cooling effect of about 3 air conditioners running for 12 hours. Average air temperature for the growing season was 0.5$^{\circ}C$ and 1.2$^{\circ}C$ cooler, respectively, in districts with 12% and 22% cover of woody plants than in a district with no vegetation. Annual $CO_2$ uptake and $O_2$ production by woody plants were 3 times greater in a district which was 2 times higher in their cover. Woody plants played, in a district with their 22% cover, an important role through offsetting total $CO_2$ emission from the district by about 3% annually, and through producing 10% of annual $O_2$ requirement by all residents within the district. Appropriate planning strategies of residential greenspace, including species selection, planting layout, greenspace enlargement, and maintenance were suggested to improve microclimate amelioration, air purification, and fire obstruction.

• Korean Journal of Soil Science and Fertilizer
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• v.13 no.4
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• pp.107-113
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• 1981

In order to investigate effects of fertilization on the yield of chestnut trees and to compare the compound fertilizer (CF) and Boron contained compound fertilizers (BCF) for chestnut trees developed by Chosun Fertilizer Inc. with single fertilizers (SF) at different fertilizing levels, a field experiment was conducted during the 1979 and 1980 growing periods. The results were summarized as follows: 1. The growth of chestnut trees was markedly improved as increasing the amount of fertilizers regardless of the SF, CF or BCF. 2. The number of strobiles increased as increased amount of fertilizers, and the ratio of dropped strobiles decreased by more than 90 percent by the BCF application while that decreased by 12 to 47 percents by the SF or CF applications. It implies that the boron application be necessary for increasing strobiles and reducing the ratio of dropped strobiles. 3. The yield increments by the SF or CF applications at the standard level were 80 percent and that by the BCF application at the same level was 202 percent and the highest yield increment was recorded as high as 302 percent by the BCF application at the doubled level in 1979. The yield response in 1980 was similar to that in 1979; however, the yields were lower than in 1979 due to the abnormal weather conditions such as low temperature and low solar radiation during summer except BCF applicated treatments where the yields were outstandingly increased. 4. The BCF developed proved as a recommendable compound fertilizer for chestnut trees.

• Korean Journal of Environment and Ecology
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• v.33 no.1
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• pp.86-106
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• 2019

We investigated the environmental conditions of natural habitats of T. nuda. The species was found on rocky northern hills ($60{\sim}90^{\circ}$) near the stream where the sea level ranges 95~145m. The average annual temperature of the habitats was lower than other places of South Korea. The differences of the lowest and the highest of the year was significantly huge than any other places. Plants were growing at the edge of stream that water reached but not submerged. Most of plants were found in North, Northeast or Northwest. It is suggested that these species require moist and low sunlight for growth. The common vegetation along with the T. nuda includes Mukdenia rossii, Selaginella rossii, Calamagrostis epigeios, and Rhododendron yedoense f. poukhanense. The dominance values and sociability of T. nuda were below 3 in all studied habitats and the variance of the number of individuals among the habitats was very high. As the optimum habitats for the T. nuda are decreasing due to the extreme precipitation patterns. It is also expected that the number of T. nuda will be decreased in the future. Therefore restoration activity in situ or ex situ must be conducted to conserve this valuable plant species.

• Journal of Internet Computing and Services
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• v.21 no.6
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• pp.95-104
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• 2020

In this paper, we propose the real time indoor air quality monitoring and controlling platform on cloud using IoT sensor data such as PM10, PM2.5, CO2, VOCs, temperature, and humidity which has direct or indirect impact to indoor air quality. The system is connected to air ventilator to manage and optimize the indoor air quality. The proposed system has three main parts; First, IoT data collection service to measure, and collect indoor air quality in real time from IoT sensor network, Second, Big data processing pipeline to process and store the collected data on cloud platform and Finally, Big data analysis and visualization service to give real time insight of indoor air quality on mobile and web application. For the implication of the proposed system, IoT sensor kits are installed on three different public day care center where the indoor pollution can cause serious impact to the health and education of growing kids. Analyzed results are visualized on mobile and web application. The impact of ventilation system to indoor air quality is tested statistically and the result shows the proper optimization of indoor air quality.

• Journal of Animal Science and Technology
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• v.64 no.6
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• pp.1046-1062
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• 2022

This study investigated the effects of L-glutamine (Gln) supplementation on growth performance, physiological traits, heat shock proteins (HSPs), and gene expression related to muscle and adipose tissue development in Hanwoo steers under heat stress (HS) conditions. Eight Hanwoo steers (initial body weight [BW] 570.7 ± 43.6 kg, months of age 22.3 ± 0.88) were randomly separated into two groups, control and treatment, and supplied with the concentration (1.5% of BW kg/day/head) and rice straw (1.5 kg/day/head). The treatment group were fed the Gln supplementation (0.5% of concentration, as-fed basis) once a day at 08:00 h. Blood samples for the assessment of haematological and biochemical parameters and the separation of peripheral blood mononuclear cells (PBMCs) were collected four times, at 0, 3, 6, and 10 weeks of the experiment. Feed intake was measured daily. BW to analyze growth performance and hair follicle collection to analyze the expression of HSPs were executed four times at 0, 3, 6, and 10 weeks. To analyze gene expression, longissimus dorsi muscle samples were collected by biopsy at the end of the study. As a result, growing performance, including final BW, average daily gain, and gain-to-feed ratio, were not different between the two groups. Leukocytes including lymphocytes and granulocytes, tended to increase in the Gln supplementation group (p = 0.058). There were also no differences in biochemical parameters shown between the two groups, except total protein and albumin, both of which were lower in the Gln supplementation group (p < 0.05). Gene expressions related to muscle and adipose tissue development were not different between the two groups. As temperature-humidity index (THI) increased, HSP70 and HSP90 expression in the hair follicle showed a high correlation. HSP90 in the hair follicle was decreased in the treatment group compared with the control group at 10 weeks (p < 0.05). Collectively, dietary Gln supplementation (0.5% of concentration, as-fed basis) may not be influential enough to affect growth performance and gene expression related to muscle and adipose tissue development in steers. However, Gln supplementation increased the number of immune cells and decreased HSP90 in the hair follicle implying HS reduction in the corresponding group.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.320-327
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• 1990

Experiments were conducted to investigate the method to raise seedling establishment rate and the optimum seeding dates and rates in direct seeding culture using transplanter under submerged field condition in Chuncheon area during 1986 to 1988. Direct seeding on submerged field using transplanting machine after sowing on seedling growing box contained with paddy or upland soil was possible. Higher rate of seedling establishment was obtained in case of sowing sprouted seed and intermittent irrigation after sowing. Seedling establishment rate was higher both in April 30 or May 10 seeding plot. Minimum daily average air and soil temperature to ensure more than 70 percent seedling establishment was 14.8$^{\circ}C$ and 16.3$^{\circ}C$ respectively. Optimum sowing date in the direct sowing was early May and optimum sowing rate was 200g per box, 6kg per l0a. In this case rice grain yield was 481kg per l0a and this is almost same yield level compared hand and machine transplanting.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.481-487
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• 1983

The need to synchronize flowering in two lines of different maturities is frequently encountered in hybrid com (Zea mays L.) seed production. To establish the methods for synchrony of flowering in parent lines of different maturities be effects of clipping at 4 and 6-leaf stages of growth and two levels, clear polyethylene mulching and five different planting dates on flowering date growth and seed yield of two dent com inbred lines of different maturities were evaluated Clipping just above the shoot-apex delayed pollen sheeding 6 to 9days and silking 5 to 13 days but reduced stand and seed yield 30 to 70% and 67 to 81%. respectively. Clipping 5cm above the shoot apex delayed flowering 1 to 4 days without stand reduction but reduced yield 3 to 29%. Laterclipping was slightly more effective for delaying flowering than earlier clipping but reduced stand more severely when clipped just above the shoot apex. Under clear polyethylene film mulching, flowering of two lines was 13 to 15 days earlier and seed yield of B68 (late line) was significantly increased. As planting was delayed from April 18 to June 13, the number of days from planting to flowering of two lines decreased due to increase in air temperature. However, growing degree days (GDD) from planting to flowering of each lines was similar regardless planting dates indicating that GDD can be satisfactoryly used for choosing the planting dates of parent lines of different maturities. Seed yields of two lines were decreased with delaying planting dates.

• Journal of Wetlands Research
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• v.25 no.2
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• pp.159-165
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• 2023

This study measured the ecological niche overlap between two deciduous oak species(Quercus acutissmia and Q. dentata) according to the change in growth responses after treating with the moisture and nutrient contents of the soil at four gradients, and interpreted the degree of competition between the two oak species by ordination method. In the moisture environment gradient, the ecological niche overlap of the two species was high in the photosynthesis-related leaf organs and low in plant architecture such as shoot length. In addition, in case of competition between two oaks, Q. dentata was remarkably dominant in soil moisture gradient, but Q. acutissimia slightly was slightly advantageous over Q. dentata in the soil nutrient gradient. These results show that even in a similar taxonomical group growing in a similar habitat, the response to the organ system of the plant varies depending on the type of environment factor, resulting in different competitive differences among plants.

• Journal of Korea Water Resources Association
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• v.56 no.9
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• pp.529-541
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• 2023

Due to the growing concern over forecasting extreme weather events such as droughts caused by climate change, there has been a rising interest in seasonal meteorological forecasts that offer ensemble predictions for the upcoming seven months. Nonetheless, limited research has been conducted in South Korea, particularly in assessing their effectiveness at the catchment-scale. In this study, we assessed the accuracy of ECMWF's seasonal forecasts (including precipitation, temperature, and evapotranspiration) for the period of 2011 to 2020. We focused on 12 multi-purpose reservoir catchments and compared the forecasts to climatology data. Continuous Ranked Probability Skill Score method is adopted to assess the forecast skill, and the linear scaling method was applied to evaluate its impact. The results showed that while the seasonal meteorological forecasts have similar skill to climatology for one month ahead, the skill decreased significantly as the forecast lead time increased. Compared to the climatology, better results were obtained in the Wet season than the Dry season. In particular, during the Wet seasons of the dry years (2015, 2017), the seasonal meteorological forecasts showed the highest skill for all lead times.

• Journal of Practical Agriculture & Fisheries Research
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• v.9 no.1
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• pp.121-132
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• 2007

1. 버섯종균 개선 버섯의 품질과 수량을 좌우하는 주요 요인은 종균의 활력이다. 그러나 라오스에서는 종균의 활력이 낮아 조그마한 100cc 병에 배양완성하는데 14일이 소요되는 등 볍씨종균의 균사생장과 균사밀도가 매우 낮음을 확인하였다. 따라서 100cc 병을 1000cc 비닐봉지로 개선하여 입봉하는데 소요되는 시간을 10배로 단축 개선하였다. 또한 곡립종균을 액체종균으로 대처한 결과 균사생장속도가 2배가 빨랐으며 작업속도가 4배가 빨라졌다. 2. 버섯배지제조 방법 개선 미세하고 건조한 톱밥에 수분을 첨가하는데 50%이하의 수분함량을 유지함으로서 균사가 표면에만 자라고 있는 것을 확인하고 버섯 배지제조 시 물리성을 개선하기 위하여 볏짚을 잘게 잘라 10%~100%까지 혼합하는 실험을 실시하였다. 그 결과 톱밥 50%에 볏짚 50% 혼합하는 것이 균사생장 속도와 밀도가 좋았다. 또한 왕겨도 30%정도 혼합한 배지처리에서 가장 좋았다. 또한 수분함량도 65%로 향상하여 혼합하도록 지도하였다. 3. 버섯배지살균 방법 개선 라오스에서는 왕겨를 태워 살균을 실시하고 있다. 화력이 약하여 살균한 배지에서 볍씨의 새싹이 돋아나오는 경우를 발견하였다. 이는 살균이 제대로 되지 않았음을 의미한다. 그래서 이동식 직화식 살균을 권하였으나 시설자재값이 감당이 안되어 엄두를 내지 못하였다. 따라서 가스버너를 도입하여 단시간에 화력을 높여 살균을 실시하므로서 세균의 증식을 막아 균사생장속도를 빠르게 하고 균사량의 축적을 높이는데 교육을 하고 컨설팅을 실시하여 개선하였다. 4. 병뚜껑과 형성틀을 대체한 링을 이용한 입봉작업시간 단축과 비용절감 버섯봉지에 배지를 담는 입봉작업을 할 때 병뚜껑과 그의 형성틀을 끼우고 솜을 조금 뜯어 톱밥배지 위에 놓는 작업을 한다. 이는 아주 잘못된 방법이다. 왜 그렇게 하는가하는 것은 이해가 간다. 그렇게 하는 이유는 접종할 때 실내에서 그냥 접종하므로 뚜껑을 열때 보호막 역할을 할 것으로 생각하고 그렇게 하는데 천만의 말이다. 어떻든 뚜껑을 열면 잡균이 들어가는 것은 마찬가지이다. 그래서 이 솜을 배지표면에 놓으면 마른 솜이 그렇지 않아도 수분이 적은데 이 솜이 수분을 또 빼앗아 가버린다. 그래서 균사생장이 늘려 15일이면 다 자라야할 균사배양기간이 한달씩 걸려도 표면만 살짝 잘린 결과가 빗어진다. 이렇게 표면만 균사가 사탕 발림식으로 자라면 품질이 저하되고 수량이 적고 병해충에 저항력이 약해지게 된다. 따라서 뚜껑과 형성틀, 솜을 모두 없애고 봉지 상단부위를 U자형으로 꺽어서 링을 끼우는 방법을 실제로 실험으로 보여준 결과 작업능률이 5배로 빠르고 작업공정이 빨라짐으로서 세균번식밀도가 적어 균사생장 속도가 2배로 빨라졌고 수량이 배가됨을 증명하고 보급하여 많은 호평을 받았다.