• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.131-137
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• 1986

Korean lawn, Zoysia japonica STEUD, is the type of a perennial warm-season lawn grass that has a naturally green period during 5 months from May to September. This study was carried out to detect the effects of N-P-K fertilization, regrowth capacity after mowing and chlorophyll contents on prolongation of the green period in Zoysia japonica grasslands. The results obtained are summarized as follows: 1. The effects of nitrogen fertilizer application on Zoysia japonica grasslands were affected on regrowth capacity after mowing, green color of leaf canopies and chlorophyll contents, respectively. 2. A the experimental plots which applied 45g/$m^2$/10 weeks of $N_3$ fertilizer, there were high significant effects on prolongation of the green period and the plots of phosphorus and potassium had additive effects. 3. Prolongation of the green period to the last ten days of October was obviously possible by slow degrees in proportion to increment of N-P-K fertilization. 4. However, it is interpreted that more prolongation of the green period is impossible with N-P-K fertilization and irrigation treatments, unless the intermediate turfgrasses between $C_3$ and $C_4$ plants must be found and bred.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.3
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• pp.214-219
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• 1991

To clarify the relationship between ambient water temperature and heading characteristics of rice (Oryza sativa L.), twelve of varieties rice were grown in a cold tolerance screening field where water temperature was controlled by continuous cold water irrigation system to test the cold tolerance of rice. When cold water was continuously irrigated with 5 cm of water depth, the water had stagnated for about three hours, and the water temperature increased gradually from inlet toward outlet in the experimental plot. The fluctuation of water temperature was well synchronized with that of ambient air temperature, and the water temperature near outlet became higher than the air temperature at the vegetative phase, while became lower at the reproductive phase of rice plant community. The leaf development rates on main culm increased by increased water temperature. The rice varities, Fukuhikari, Sangpungbyeo and YR3486-16-2 were more sensitive than the others in the response of leaf development to water temperature. However, Janack and Milyang 42 were comparatively less sensitive to water temperature in leaf development. Janack and Paro -white rices required longer days to develop one leaf on main culm at reproductive phase than at vegetative phase. Varietal difference in days required to develop one leaf on main culm of rice plant was more distinctive at the reproductive phase when water temperature was relatively lower than at the vegetative phase with relatively higher water temperature condition. No difference was found between the growth phases, vegetative and reproductive, in the response of average leaf developmental rates to water temperature under the similar air temperature condition. The estimated average days required to develop one leaf on main culm decreased by 1.3 day by 1$^{\circ}C$ increase in water temperature. Varietal differences in the total number of leaves on main culm depended upon the water temperature, in which the varieties such as Fukuhikari, Gwangmyeon-gbyeo, China 988, and YR3486-16-2 showed increased one leaf by increased water temperature, while Sobaekbyeo, Paro-white, Sangpungbyeo, Pungsanbyeo, Samgangbyeo, and Milyang 42 were kept at the same leaf number regardless of water temperature. However, the total leaf number on main culm and days to heading of Janack increased by increased water temperature. The other varieties showed the shortened days to heading by the increase in water temperature with noticeable varietal differences regardless of the variation in the total number of leaves on main culm.

• Economic and Environmental Geology
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• v.20 no.4
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• pp.273-288
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• 1987

연화(蓮花) 연(鉛) 아연광산(亞鉛鑛山)은 광체(鑛體)의 분포(分布)에 따라 본산지구(本山地區), 동점지구(銅店地區) 및 태백지구(太白地區)로 구분할 수 있다. 태백지구(太白地區)에 대한 본격적인 탐광(探鑛)이 시작되기 전인 1981년 당시, 약 25년 동안 채광작업(採鑛作業)이 진행되어 온 본산지역(本山地域)은 주종광체(主宗鑛體)인 월암(月岩) 및 남산광체(南山鑛體)가 -600m level에서 하한(下限)이 드러남에 따라 광량(鑛量)이 크게 소진(消盡)된 상태였으며, 동점지성(銅店地城)은 상하(上下)의 광황변화(鑛況變化)는 크지 않으나 광체(鑛體)의 규모(規模)가 비교적 작아, 조업(操業)의 안정(安定)을 위해서는 신광화대(新鑛化帶)의 개발(開發)이 시급(時急)한 과제(課題)로 대두되었다. 이에 따라 평천(平川), 태백(太白), 동점역(銅店驛), 방터골, 삼방산광화대(三芳山鑛化帶) 등 연화(蓮花) 전역(全域)에 걸쳐 모암(母岩)의 분포(分布), 지질구조(地質構造), 광징(鑛徵) 등을 검토한 결과 탐광대상(探鑛對象)에서 제외되어 왔던 태백지구(太白地區)가 다음과 같은 점에서 유망(有望)한 탐사후보지(探査候補地)로 부각되었다. 첫째, 지표(地表)에서는 풍촌석회암층(豊村石灰岩層)이 분포(分布)되지 않으나 지질구조(地質構造)를 검토한 결과 -300m level 하부(下部)에서는 이의 전층(全層)이 분포(分布)할 것으로 예상되며, 둘째, 두무동층(斗務洞層) 및 동점규암층내(銅店珪岩層內)에서 발견된 광징(鑛徵)들이 하부(下部)의 풍촌석회암내(豊村石灰岩內)로 연장(延長)되면 부광부(富鑛部)를 이룰 것으로 기대되고, 셋째, 지층(地層)의 경사(傾斜)가 $50^{\circ}$ 이상(以上)인 점, 석영반암(石英斑岩)이 분포(分布)하는 점 등은 광상배태(鑛床胚胎)에 양호(良好)한 조건(條件)이고, 넷째, 본산지구(本山地區)의 월곡(月谷), 월암(月岩), 남산(南山)등 주종광화대(主宗鑛化帶)의 연장부(延長部)인 점, 다섯째, 중앙견갱(中央堅坑)으로부터 약 2km 거리로 탐사단계(探査段階)에 별도의 신규투자(新規投資) 없이 굴진(掘進)이 가능하다는 개발조건상(開發條件上)의 이점(利點)이 있었다. 이에 따라 태백지구(太白地區)에 대한 지표정사(地表精査), 물리탐사(物理探査) 및 지화탐(地化探)을 실시하고, 20여년간 축적된 연화광산(蓮花鑛山)의 지질(地質), 광상자료(鑛床資料)를 정리(整理), 그 특성(特性)을 태백지구(太白地區) 탐사(探査)의 가설(假說)로 적용하여 시추계획(試錐計劃)을 수립, 1982년 구조시추(構造試錐)를 실시한 결과 지질구조(地質構造), 풍촌석회암층(豊村石灰岩層)의 분포(分布) 등이 거의 예상했던 대로 밝혀졌으며 태백(太白) 1호광체(號鑛體)의 일단(一端)이 확인되기에 이르렀다. 1983년(年) 7월(月) 본산지구(本山地區) -600m level에서 태백(太白) 크로스 탐광굴진(探鑛掘進)이 착수되었으며, 1985년에 마침내 갱내(坑內)에서 태백(太白) 1호(號), 2호(號) 광체(鑛體)가 착광(着鑛)되었다. -600m level에서의 태백(太白) 1호광체(號鑛體)의 규모(規模)는 연장(延長) 300m, 평균맥폭(平均脈幅) 8.5m이며, 품위(品位)는 Pb 4.5%, Zn 4.5%, Ag 109g/t이다. 태백광화대(太白鑛化帶)의 지질학적(地質學的) 예상광량(豫想鑛量)은 1,000만(萬)t 이상(以上)이 될 것으로 추정(推定)되며, 현재 -480m level에서 -720m level에 이르기까지 5개 level에서 가행(稼行)되고 있다. 현재 level에서 태백(太白) 1호(號) 광체(鑛體)는 풍촌석회암층(豊村石灰岩層) 및 화절층(花折層)을 모암(母岩)으로 하여 맥상광상(脈狀鑛床)으로 생산(生産)되며, 맥석광물(脈石鑛物)은 능망간석, Mn-방해석(方解石), 방해석(方解石), 석영(石英) 등이고 광석광물(鑛石鑛物)은 섬아연석(閃亞鉛石), 방연석(方鉛石), 황철석(黃鐵石), 자유철석(磁硫鐵石), 유비광석(硫砒鑛石), 황동석(黃銅石), 사면동석(四面銅石), 엘렉트럼 등이다. 태백지구(太自地區)는 광상(鑛床)의 산출상태(産出狀態) 및 지질(地質), 광상학적(鑛床學的) 환경(環境)이 본산지구(本山地區)와 거의 동일(同一)함이 밝혀지고 있다. 태백지구(太白地區)에서는 현재 태백(太白) 1호(號), 2호(號), 3호(號), 5호(號) 및 절골 1호(號), 2호(號) 등 6개 광화대(鑛化帶)에 대한 탐광(探鑛)이 진행되고 있다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.45-54
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• 2006

The study was to review methods by which a ship can unfold and tow an oil boom by attaching the opening apparatus to an oil boom through experiments. The shape and dimension of the opening apparatus were designed with the measurement value of the towing tension load of the oil boom and the dimension of winch drum of the oil boom installed in the ship considered. For the field experiment to identify the performance of the opening apparatus, opening apparatuses were prepared to have the dimension of $3.0m^2$ and $6.0m^2$ which is 91% and 75% of the calculation value for type B and C respectively. As a result, T(kg), the value of tension in type B oil boom according to the towing speed(v) change when two ships are towed together were proved to be $T=920v^{1.1}\;and\;T=500v^{0.9}$ in case the distance is 100 m and 50 m. Based on the result, the dimension of the opening apparatus for type B and C oil boom was calculated as $3.3m^2$ and $8.0m^2$ respectively. When unfolding and towing by attaching the opening apparatus and 200 m of towing line at both ends of type B and type C oil boom, the maximum width of the opening apparatus was shown as 114 m and 95 m in average(width of opening/total length of oil boom: 33% and 57%) in the towing speed of 1.5 kt. It was evaluated that the opening apparatus could concentrate the spilled oil in a good performance. However as far as the increase rate of oil boom opening width according to the length of the towing line is debatable, the increase rate is remarkably reduced when it is lengthened from 100 m to 150 m and to 200 m although it showed extreme increase of 31% and 40% when the length of the towing line was changed from 50 m to 100 m. Therefore, it is inferred that the towing line should be maintained more or less 100 m to get good spread efficiency of the opening apparatus. Additionally, if the towing speed is faster than 1.5 kt, the opening width was narrowed because of the reduced spread efficiency and the shape of the oil boom can be unstable because of the partial sinking of the oil boom, run over waves, or flap of skirt. Thus the reasonable towing speed can be within 1.5 kt for the operation of the opening apparatus.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.255-261
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• 2015

Purpose: purchasing status and understanding trends of Functional progressive addtions lenses buyers', Correlation analysis of the Binocular Function value to determine ADD then can be apply sales and prescriptions. Methods: Years 2011 to 2014, 298 patients who were prescribed functional progressive lenses were analysed based on the prescription data and SPSS (Ver. 20.0) was treated using the statistics. Results: Results: The average age of our customers are $27.66{\pm}11.55$ years, average addition power is $+0.73{\pm}0.36D$, customers are using take a prescription of ADD $+0.75{\pm}0.28D$ was the highest 44.33% to 132 people. Near point of convergence of 276 people (92.62%) was mostly less than 10 cm, and near point of accommodation of 134 people (44.97%) was also below 10 cm, within 11~15 cm were 122 people (40.94%). Most of people were within normal range in terms of Near point of convergence and near point of accommodation, near point of accommodation tend to be longer than Near point of convergence. As you can see this result shows most of customers need extra help in their near point of accommodation instead of they are leak at it. FCC (Fused cross cylinder) check Value and ADD (addition power) tests showed that the value of a strong correlation (p=0.00), NPC and NPA were also p=0.001, the correlation of the NPC and ADD is p=0.003, In addition, NPA and ADD also showed a significant correlations (p=0.005). Near Point of Accommodation, negative relative accommodation, and positive relative accommodation are all significantly correlated (p=0.00). The short distance-related variables of the ADD which are NPC, NPA, Age, also appeared to side correlate significantly with each other. Conclusion: Binocular function values of the subjects were highly correlated with each other so precise examination is required. when Age young people are working at short distance, low ADD values was prescribed for solving discomfort. So, in the case of early presbyopia, accommodative insufficiency, or people feel fatigue when they often working at near although their accommodation function is normal, when functional progressive lenses are prescribed, expectation of this should be exactly notified.

• Geophysics and Geophysical Exploration
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• v.10 no.3
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• pp.191-202
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• 2007

To identify the detailed attenuation structure in the southern Korean Peninsula, a numerical test was conducted for the Q tomography inversion to be applied to the accumulated dataset until 2005. In particular, the stochastic pointsource ground-motion model (STGM model; Boore, 2003) was adopted for the 2D Q tomography inversion for direct application to simulating the strong ground-motion. Simultaneous inversion of the STGM model parameters with a regional single Q model was performed to evaluate the source and site effects which were necessary to generate an artificial dataset for the numerical test. The artificial dataset consists of simulated Fourier spectra that resemble the real data in the magnitude-distance-frequency-error distribution except replacement of the regional single Q model with a checkerboard type of high and low values of laterally varying Q models. The total number of Q blocks used for the checkerboard test was 75 (grid size of $35{\times}44km^2$ for Q blocks); Q functional form of $Q_0f^{\eta}$ ($Q_0$=100 or 500, 0.0 < ${\eta}$ < 1.0) was assigned to each Q block for the checkerboard test. The checkerboard test has been implemented in three steps. At the first step, the initial values of Q-values for 75 blocks were estimated. At the second step, the site amplification function was estimated by using the initial guess of A(f) which is the mean site amplification functions (Yun and Suh, 2007) for the site class. The last step is to invert the tomographic Q-values of 75 blocks based on the results of the first and second steps. As a result of the checkerboard test, it was demonstrated that Q-values could be robustly estimated by using the 2D Q tomography inversion method even in the presence of perturbed source and site effects from the true input model.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.34-43
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• 1996

We investigated the vegetation structure, and effects of canopy degree(gap or purlieu to 25%, 50%, 75%, over 75%) of the overstory on seedling regeneration and survivorship, and sapling density, growth and growth type of Abies koreana in subalpine of Mt. Chiri. The stem density in Abies koreana stand was higher in middle story than upper story, individual trees in upper story occupied larger area and were more apart, resulted in uniform distribution. The regeneration and survivorship of seedlings and saplings were best in 25% of crown closure, in order of 50%, gap, but lowest in over 75% of crown closure. The annual growth rate and recent 5 years growth rate of saplings were highest in gap or purlieu and getting lower toward gradually higher coverage of overstory. And 10- to 20-Year-old saplings were mainly regenerated in stands with lower density(I or II), but most of 20 to 30 years old saplings were growing in stands with higher density (III or IV). The number of "A" type saplings grown normally in gap or purlieu was gradually decreased in stand with higher density but the number of "D" or "E" types of which growth was supressed or prohibited by the high density was abruptly increased. Saplings normally growing in the gap and purlieu showed the panicle type, but those grown under dense crown were greatly suppressed and showed the umbellate type.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.252-265
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• 2017

This study aims to analyze the landscape ecological characteristics of green spaces within built up area of high density and evaluate the potential applicability of green patches, thereby introducing urban garden for generating green networks in residence areas. To this end, Yeoksam-Dong was selected as the site area since it is classified as both green initiative zone and alienated area of park service in Seoul. First, the current condition of green spaces in Yeoksam-Dong was identified by five categories: Street trees, private garden, public pocket garden, rooftop garden, and park. Then, the landscape index analysis through FRAGSTATS and connectivity assessment via multi-buffer zone analysis were carried out for analyzing the green networks and evaluating the potential value of green space. The results showed that the degree to which green areas in the site were distributed is arranged in the order of street tree, private garden, public pocket garden, park, and rooftop garden. In case of the street trees whose total core area (TCA, $1,618m^2$) is as high as the park's ($1,128m^2$). Private garden has potential for green network in built up area of high density by gardening since the shape of the patches are irregular (ED = 78.1m/ha) and the average distance among the patches is close (ENN=33.9m). Public pocket garden has also potential for gardening according to the result that it was found to be distributed evenly (LPI=5.7%, SHEI=0.9) with exposing external disturbance ($TCA=66m^2$). For the green network, 84% of all the study site is covered by small green network in 50m butter range of connected green area. The effect of green network was expected through gardening in public pocket garden (27%) and street tree (26%). Accordingly, it is encouraged to actively utilize street tree, private gardens, and rooftop gardens and to establish the urban gardens like local-based community gardens in public pocket garden where a variety of activities can be carried out near residential areas. By doing so, green networks can effectively be established in built up area with high density. The results of this study can contribute positively to fostering the creation of various types of urban gardens.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.189-195
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• 2020

This research was carried out to find the proper number of stem training and position of fruit setting that can be stably produced for the cultivation in small and medium types of watermelon during winter. The treatments for the number of stem training were 2-, 3-, 4-stems, respectively. Growth characteristics (plant height, stem diameter, no. of node, etc.) by number of stem training were higher in 2-stem than in 3-4-stem. However, Fruit characteristics such as weight, length, width were high in the 4-stem. There is no significant difference between the soluble solids and fruit setting rate depending on the stem training. The position of fruit setting were three points: 2nd, 3rd, 4th female flower positions. The fruit setting is one fruit per plant. The average fruit setting nodes of 2^nd, 3^rd and 4^th female flowers were 11.5, 15.8 and 23.1 nodes, respectively. The 4^th female flower was 0.8 kg heavier than 2^nd female flower because of its increased weight as position of fruit setting was higher. However, the soluble solids decreased as the position of fruit setting increased, with the second female flower being 1.3°Bx higher than the 4^th female flower. The Fruit setting rate was no significant difference. Considering the growth and fruit characteristics, it is believed that the small and medium-sized watermelon in winter will have a high quality production of watermelon when the stem training is 3-stem and the position of fruit setting is 3^rd female flower. However, it is thought that additional studies are needed to stabilize the income of watermelon-growing farms, such as planting distance and adhesion of small and medium-sized varieties.

• Progress in Medical Physics
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• v.24 no.4
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• pp.253-258
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• 2013

The purpose of this study is to evaluate and analyze the relationship between the external radiation dose reconstruction which is transmitted from the patient who receives radiation treatment through electronic portal imaging device (EPID) and the internal dose derived from the Monte Carlo simulation. As a comparative analysis of the two cases, it is performed to provide a basic indicator for similar studies. The geometric information of the experiment and that of the radiation source were entered into Monte Carlo n-particle (MCNPX) which is the computer simulation tool and to derive the EPID images, a tally card in MCNPX was used for visualizing and the imaging of the dose information. We set to source to surface distance (SSD) 100 cm for internal measurement and EPID. And the water phantom was set to be 100 cm of the source to surface distance (SSD) for the internal measurement and EPID was set to 90 cm of SSD which is 10 cm below. The internal dose was collected from the water phantom by using mesh tally function in MCNPX, accumulated dose data was acquired by four-portal beam exposures. At the same time, after getting the dose which had been passed through water phantom, dose reconstruction was performed using back-projection method. In order to analyze about two cases, we compared the penetrated dose by calibration of itself with the absorbed one. We also evaluated the reconstructed dose using EPID and partially accumulated (overlapped) dose in water phantom by four-portal beam exposures. The sum dose data of two cases were calculated as each 3.4580 MeV/g (absorbed dose in water) and 3.4354 MeV/g (EPID reconstruction). The result of sum dose match from two cases shows good agreement with 0.6536% dose error.