• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.31.2-31.2
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• 2018

미국 유타주 유타사막에 설치된 MDRS(Mars Desert Research Station)는 미국의 비영리기구인 화성학회(The Mars Society)에서 운영하는 화성탐사연구기지다. 화성학회는 1998년 우주비행사, 천문학자, 과학자 4000여명이 모여 만든 비영리연구단체다. 2001년 미국 유타주에 문을 연 MDRS에서는 토양 미생물 검출실험, 태양에너지 조리실험, 영구동토층 연구, 해빙 연구, 드론 정찰 및 지도 작성 등 인류가 화성에 도착했을 때 실제 수행할 연구들을 진행하고 있다. tVN <갈릴레오 : 깨어난 우주> 촬영 차 MDRS에 머물며 과학실험을 수행한 사례를 공유하고 이를 통해 천문학 및 우주탐사에 대한 대중화 방안에 대해 논의해 보고자 한다.

• Journal of Korean Society of Forest Science
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• v.105 no.3
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• pp.275-283
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• 2016

The objective of this study was to examine carbon dynamics with biomass, soil $CO_2$ efflux, litter and root decomposition after tree density control in young Pinus densiflora stands. The stands were established with 50% thinning, clear-cut, and control stands with three pseudo-replicated plots and a bare soil plot in 8-year-old Pinus densiflora nursery field. Monthly measurements were conducted from March 2012 to February 2014 and aboveground biomass and coarse-roots were estimated by derived allometric equations. Average diameter growth at root collar in control and thinned was 0.89 cm and 1.48 cm per year, respectively, and the diameter growth of control stand was significantly higher than that of thinned stands (p<0.05). Total biomass was estimated to 5.17, $4.85kg\;C\;m^{-2}$ per year in control and thinned, respectively. Annual soil $CO_2$ efflux in control, thinned, clear cut, and bare soil was 3.71, 3.90, 4.17, $4.56kg\;CO_2\;m^{-2}\;yr^{-1}$, respectively and removing trees significantly increased soil $CO_2$ efflux (p<0.05). Net Ecosystem Production (NEP) was 1.57, 1.36, -0.67, $-1.25kg\;C\;m^{-2}\;yr^{-1}$ in control, thinned, clear cut and bare soil in the young Pinus densiflora stands. NEP was significantly decreased by removing trees. Thinning increased diameter at root collar and carbon of individual tree and recovered 86% of carbon removed by thinning after one-year. In addition, soil $CO_2$ efflux increased and NEP increased by thinning. Results of this study, tree density control such as thinning increased the carbon storage and growth of the young Pinus densiflora stands.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.223-228
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• 2011

This research was performed to investigate change of green speed according to growth of grass, for this, the method of effective green management for improvement of green speed was searched by investigating green density, soil moisture, surface hardness, and mowing height every day for 6 months. As the result of the study, reliability between, green density, soil moisture, surface hardness, mowing height and green speed were measured to be respectively 0.4742, 0.5690, 0.4632, 0.2806, i.e. soil moisture is considered as the factor which affects green speed the most. Therefore, it will be an advantageous environment to maintain soil moisture a little bit low to improve green speed within the range that does not disrupt the growth of green. In case of green density, it is considered to be effective to get a fast green speed when obtaining enough density during May~June, the most vigorous growth period and at the same time green up period. Surface hardness was confirmed that management work as rolling is a considerably effective method to increase hardness. However, rolling gives high stress to the green, combining another management work as regular hilling could be a good alternative. Reliability of green preview and green speed was 0.2806, lower than soil moisture or surface hardness. Through the results, it was confirmed that management of mowing height to be low less than 3.00 mm is helpful to improve green speed, timely, and it is advantageous to manage green speed when adjusting mowing height during the vigorous growth period of bent grass. However, considering the range of mowing height was not various, being 2.9~3.4 mm, henceforth research on investigation of green speed at more various mowing heights would be necessary. Consequently, except mowing height, other three factors, i.e. green density, soil moisture and surface hardness were investigated to have considerable level of reliability on green speed, and it is considered that each factor affects green speed respectively according to green condition and time. Accordingly, in order for the manager to maintain high speed all year round, intensive care for each factor per time unit considering green growth condition is considered to be necessary.

• Korean Journal of Environmental Biology
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• v.25 no.1
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• pp.1-7
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• 2007

Medaka(Oryzias latipes) and earthworm(Eisenia fetida) toxicity tests were carried out and ecological risk assessment in water and soil was performed with national monitoring data. NOEC of alachlor was $100\;{\mu}g\;L^{-1}$ in the medaka early life-stage test. Embryonic development, hatchability and time to hatching of medaka eggs were affected by this chemical. The $LC_{50}$ and NOEC of alachlor were $94.1\;mg\;kg^{-1}\;and\;55.0\;mg\;kg^{-1}$, respectively, in the earthworm acute toxicity test. The environmental monitoring has been carrying out by NIER since 1999. Exposure levels of alachlor in water and soil were $ND{\sim}0.54\;{\mu}g\;L^{-1}\;and\;ND{\sim}0.9\;{\mu}g\;kg^{-1}$, respectively, in national monitoring data which had been performed from 2000 to 2004. The measured water and soil exposure levels were applied to evaluate the environmental risk assessment. The PNEC of alachlor in water and in soil were determined as $1\;{\mu}g\;L^{-1}\;and\;55.0\;{\mu}g\;kg^{-1}$, respectively using the safety factors which were suggested in EU and OECD. The HQs (PEC/PNEC) were determined to be below 1 for both water and soil when the maximum exposure levels ($0.54\;{\mu}g\; L^{-1}$ in water and $0.9\;{\mu}g\;kg^{-1}$ in soil) were applied. Conclusively, our study indicated that there was not significant ecological risk of alachlor in water and soil of our monitoring sites.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.4
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• pp.215-220
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• 1980

This is a review of the theory and practical uses of the $Hom{\grave{e}}s$' systematic variations in the fertilizer experiments. General characteristics of the method are as follows : 1 ) It could be recommended as a reasonable met hod for fertilizer experiments in order to improve the weak points in the conventional methods. 2 ) This met hod is a determination of the total amount of nutrients and the relative proportion of each nutrient in the total. 3 ) Concerning of the high yields of crops this met hod should be adapted for the systematic fertilization. 4 ) This is an usable method not only for the macro- but also micro elements investigations.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.39-39
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• 2017

본 연구에서는 매실 생산성 향상 분석을 위해 범용 싱글보드 컴퓨터로 제작한 원격 데이터 수집 장치를 개발하였다. 라즈베리파이와 같은 소형 범용 싱글보드 컴퓨터는 저렴하게 IoT 기반의 원격 모니터링 장치를 쉽게 개발할 수 있어 중소규모 매실 농장의 생육 환경 정보 및 재배 이력을 수집하는데 활용도가 매우 높아 생산성 향상을 위한 데이터 수집 분야에서 잠재적인 가능성을 가지고 있다. 따라서 매실의 생산성을 높이는데 영향을 줄 수 있는 환경적, 생육적 요인들을 분석하기 위한 기초적인 단계에서 이러한 소형 싱글보드 컴퓨터를 이용한 원격 센싱 및 데이터 수집 장치를 개발하였다. 수집데이터로는 주변 기온과 습도, 토양의 온도와 수분함량 및 pH이다. 1차 프로토타입은 아두이노 MKR1000을 사용하여 주변 온도 및 습도 데이터 수집 및 전송 장치를 제작하고 대표적인 통신사인 KT가 운영하는 IoT Makers라는 클라우드 저장소를 사용하여 시스템을 구성하였다. MKR1000을 사용한 데이터 수집 장치의 장단점을 평가하기 위해 실내 시험을 실시하였다. 현재는 라즈베리파이를 이용한 주변 기온과 습도, 토양의 온도와 수분함량 및 pH 데이터 수집 및 전송 장치를 제작하였다. 최종 개발된 데이터 수집 장치는 2017년 순천 인근의 매실 밭에 설치되어 실제 센싱 데이터를 수집할 예정이며 수집한 데이터는 매실 생산성 향상과 관련된 요인을 분석하는데 사용할 것이다. 저가의 범용 IoT 장치를 활용한 원격 데이터 수집을 넓은 범위의 매실포장에 활용한다면, 매실의 생산성 및 품질 향상은 물론 매실의 이력추적관리의 기초 데이터를 적은 비용과 노력으로 제공할 수 있을 것으로 판단된다.

• Microbiology and Biotechnology Letters
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• v.29 no.3
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• pp.186-193
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• 2001

A powerful antagonistic bacterium against Phytophthora capsici causing phytophthora blight of red pepper was isolated from the cultivated soil in Kyongju Korea, The bilogical control mechanisms of the isolated strain were caused by strong antifungal antibiotic, siderophore and cellulase. The strain was identified as Chryseomonas luteola by the cultural morphological and physiological characteristics. The opti- mal culture medium for the antibiotic production was determined as follows : 0.15%D(+) cellobiose, 0.55% $NH_4$CI, 0.01% KCI 0.7% $K_2$$HPO_4$ 0.2% $KH_2$PO$_4$ and 0.5% sodium citrate at pH 7.0 The optimal incubation time was 84 hours at $30^{\circ}C$ In pot bioassay, the treatment of C luteola 5042 protected red pepper plant against the blight of Phytophthora capsici.

• 보존과학연구
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• s.34
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• pp.84-99
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• 2013

There are more than 2,900 different species of termites in the world, and just there are 23 species in Japan. They caused more severe infestation compared with Korea. When a structure has become infested with termites, it is important that appropriate action must be taken: the chemical pest control (fumigation, soil termiticide treatment, bait system etc.) or the non-chemical pest control (low oxygen treatment, carbon dioxide treatment, high/low temperature treatment etc.). Especially, there were attempts to make practical protocol of various alternatives since the fumigant(methyl bromide) had been phased out in 2005 in Japan, and practically non-chemical methods would be effective alternatives for some cases, where the scale of infestation is small and limited and when long treatment is possible. But most of all, it is important that the process of pest control is made according to each species of termites with consideration for different characteristics of termites.

• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.473-479
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• 1994

This study was carried out to get the basic data for obtaining water resources continuously. Water storage of forest land was estimated by effective water storage based on classifying soil pore. The results were summarized as follows ; 1. Percentage of coarse pores were in the order : Forest>Bare land>Grasses. As soil depth increased, total pores, coarse pores, and maximum water content were decreased, while fine pores increased. 2. Soil pore percentage and physical properties of surface layer(0~20cm) were significantly different among forest floor conditions. However, there were no difference in soil pore percentage and physical properties in 20~40cm and 40~60cm according to forest floor conditions. In the same plot, on the other hand, soil pore percentage and physical properties were significantly different between surface layer(0~20cm) and 20~40cm, but there were no differences between 20~40cm and 40~60cm. 3. Effective water storage was highly correlated with coarse pore in all plots. 4. The model for water storage capacity of each forest floor condition expressed by effective water storage was produced using coarse pores and soil depth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.370-375
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• 1996

This study was conducted to find out the feasibility in direct seeded rice cultivation on the reclaimed saline soil. Seedling emergence was tested under the different application rates of rice straw and seeding depth, and also under combined treatments soil moisture regimes and seeding depth on saline soils in a greenhouse. The comparison of seedling stand and yield performance of rice in rotary till after broadcast seeding and in non-plow after broadcast seeding were tested on a field that reclaimed saline soil. Seedling emergence ratio in application of rice straw(4 and 6 tons /ha) was higher than that in non-application of rice straw. Seedling emergence and plant height were remarkably increased with the shallow seeding depth in the application of rice straw(4 tons /ha). The seedling emergence under proper soil moisture condition(25%) was higher than that under excess soil moisture condition(35%). Under proper soil moisture condition, the plant height was increased with the shallowed seeding depth. The number of seedling stand per m$^2$ in non-plow after broadcast seeding was larger than that in rotary till after broadcast seeding. Panicle number per m$^2$ in non-plow after broadcast seeding was much larger than that in rotary till after broadcast seeding and the yield showed the same trends as panicle number.