• Journal of the Korean earth science society
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• v.30 no.2
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• pp.185-195
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• 2009

We investigated the change of several meteorological variables due to deforestation. We established two sets of automatic weather observation system: one on a hill where forest was destructed by lumbering (Point 1) and the other in a neighboring district (Point 2) of fairly preserved forest. The observations were continued for one year (2006. 12-2007. 12). In this study, we analysed the data observed for one week from the nea day after summertime rainfall. The results showed that the air temperatures of Point 1 were about $1.5^{\circ}C$ higher than those of Point 2 during the daytime. But there were small gaps between the two poults during the nighttime. The relative humidities also differed greatly between the two during the daytime. It was as high as about 10% at Point 2. The surface and underground (15 cm in depth) soil temperatures were also fealty different between the two points during the daytime. They were $3-10^{\circ}C$ higher at Point 2 than those of Point 1. And the gaps reduced drastically during the nighttime. The averaged soil moistures were 7.1% at Point 1 and 19.5% at Point 2 during the observation period, respectively. The differences of wind direction were small, but the wind speeds differed between the two points. The observed wind speeds during the observation period were roughly estimated to be about 0.5m/s at Point 1 and 0.3m/s at Point 2. The heat budget analysis was also performed based on the observation data.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.4
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• pp.49-63
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• 2010

This study focused on the method of separation - space organization- as one of the architectural methods that is considered by the view point of its location and arrangement of 'Byoul-seo' private garden pavilion in Honam province. As a result, the followings are conclusions; By this study, they can be found in the concept of '居敬窮理', '格物致知'. It is presumed that nature union is archived through the 'yan-sang(玩賞)' which is ultimate state of knowledge that is based on the premises of opened significance in emancipation from narrow view point in the past and cognition of value. Therefore, it is needed to know the unworldly point of space perception about the pavilion territory, furthermore to have conceptual method to distinct pavilion from the world. there are two methods in the distinct concept in this pavilion research: unworldly separation and meditative separation. It is concluded that the specific consideration of the method of separation that is applied in the Byoul-seo pavilion. And it is accomplished by the contemplation of separation method in approach and entrance of direct influence area. they could be 1) cross the hill, 2) cross over a brook, 3) lifted up in the mount, 4) penetrate the forest, and 5) narrow entrance, which could be part of location.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.2
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• pp.105-109
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• 2004

Field studies were conducted in the southeastern Korea ($36^{\circ}$N) on a commerce silt loam soil at paddy field. Seed were manually planted on 16 July 2003. Plants were planted with plant densities of 70${\times}$10 cm (row width x plant spacing), 50 x 10 cm, and 30 ${\times}$10 cm. Two seedlings per hill were taken prior to V3 stage. Fertilizer was applied prior to plant at a rate of 30-30-34 kg (N-$\textrm{P}_2\textrm{O}_5$-$\textrm{K}_2\textrm{O}$) per ha. Experimental design was a randomized complete block in a split plot arrangement with three replications. Yield from different planting densities responded similarly in three soybean cultivars and increased when planting density increased. Somyeongkong showed the highest increasing rate of yield about 26% by 338 g $\textrm{m}^{-2}$ at 30 x l0 cm compared to yield of conventional planting density (70 x 10 cm). Also, the planting density significantly affected pod and seed number and seed weight, but not seed per pod. The tallest plant appeared at 30${\times}$10 cm. The change of leaf area according to days after emergence showed differently in soybean cultivars. The highest and lowest total dry matter production per square meter appeared at 30 x 10 cm and at 70 x 10 cm, respectively. Crop growth rate (CGR) showed greater at R3∼R4 stages compared with V7∼R2 or R2∼R3 growth stages and showed the greatest at 30 x 10 cm in three soybean cultivars. As late planted soybean, there was a significant relation between seed yield and CGR, and leaf area index (LAI) according to planting densities at before and after the flowering stage. Relationship between seed yield and CGR in three planting densities showed a highly significant positive relation ($\textrm{R}^2$=0.757) at R3 to R4 stages, and significant relations ($\textrm{R}^2$=0.505, 0.617) at V7 to R2 and V2 to V3. Also, there was a highly significant positive difference between seed yield and LAI during R3 to R4 and R2 to R3 stages.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.133-138
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• 2010

This study was conducted to analysis a major cause of rice yield reduction in 4 research points, 1, 2, 3, and 5km, from coastline in the East Sea. There were great changes of temperature in each research point, though the average temperature a day was no difference between each research point. Each temperature in 1, 2, and 3km research points was 8, 7, and $4^{\circ}C$ lower than in 5km when cold salty wind was generated due to cold pool. As it was close in coastline, its soil was abundant sand components, little silt and clay soil components and lacking in cation exchange capacity(CEC). And plant height became a smaller, heading date was delayed for 3～4 days, and dry weight was reduced. Also, it was to be down percent of fertile grain. As cultivation site was close in seaside, its decline was larger because of reduction of panicle number per hill. It was "Samdeogbyeo" that was variety adapted in cold salty wind, having yield potential more than 90% in 2km.

• Analytical Science and Technology
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• v.25 no.2
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• pp.152-157
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• 2012

Currently, many types of compound preparations are being used but the quality control guidelines for their use are lacking. In case of single compound drug, the quality control methods are specified in the pharmacopeia. However, there is no method to simultaneously analyze compound preparations. In this study, a simple validated analytical method for HPLC separation of chlorquinaldol and promestriene is introduced. Validation was divided into categories including linearity, precision, accuracy (recovery) and system suitability. The contents of the products which are on the market were monitored using the validated analytical method and the robustness of the analytical method was tested by conducting an inter-laboratory validation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.6
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• pp.1313-1318
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• 2006

The mechanism fur the surface film formation was studied by in situ Atomic Force Microscopy (AFM) observation of a highly oriented pyrolytic graphite (HOPG) basal plane surface during cyclic voltammetry at a slow scan-rate of 0.5 mV $s^{-1}$ in 1 moi $dm^{-3}$ (M) $LiPF_6$ dissolved in a mixture of ethylene carbonate (EC) and diethyl carbonate (DEC). Decomposition of the electrolyte solution began at a potential around 2.15 V vs. $Li^+$/Li on step edges. In the potential range 0.95-0.8 V vs. $Li^+$/Li, flat areas (hill-like structures) and large swelling appeared on the surface. It is considered that these two features were formed by the intercalation of solvated lithium ions and their decomposition beneath the surface, respectively. At potentials more negative than 0.80 V vs. $Li^+$/Li, particle-like precipitates appeared on the basal plane surface. After the first cycle, the thickness of the precipitate layer was 30 nm. The precipitates were considered to be decomposition of the lithium salt ($LiPF_6$) and solvent molecules (EC and DEC), and to have an important role in suppressing further solvent decomposition on the basal plane.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.114-120
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• 2000

The aim of this study was to investigate the effects of slow-released nitrogen fertilizer(SRNF) on the growth and yield of rice. SRNF produced from wasted paper was applied to a clay loam paddy field comparing to urea fertilized field and only P-and K-fertilized field. Some agronomic components like as growth development and yield component were observed and physico-chemical properties of the soils were analyzed. Plant height and tiller numbers per hill showed higher in rice plant treated with SRNF than in one treated with urea at the early grow stage whereas they appeared to be all much the same at the end of growth stage. While the chlorophyll content in SRNF-treated rice shoot was higher than in urea-treated one, the photosynthetic activity in urea-treated rice shoot was slightly higher than in SRNF-treated rice. In harvested grain, the nitrogen content was higher than in SRNF treated rice than in urea treated rice, but in straws the content was less. At the harvesting stage, nitrogen uptake in grains was about 4% higher in SRNF-treated rice than in urea treated rice whereas in straws rather 20% lower. The N efficiency in SRNF treated rice was lower than in urea treated rice. In the soils treated with SRNF, pH, organic matter and phosphorus were higher than in the soils treated with urea. Total N content in SRNF treated soil was lower after experiment than in urea treated soil.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.3
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• pp.169-175
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• 1985

This experiment was carried out during 1983-1984 to determine an effective method for the introduction of pasture species on nonarable hill country without cultivation. In this experiment, 1.8 and 2.8kg a.i. $ha^{-1}$ rates of glyphosate and a 0.7kg a.i.$ha^{-1}$ rate of paraquat were applied, and also 30, 45 and 60 days intervals between spraying and sowing were used. Establishment of orchardgrass (Dactylis glomerata) was not affected by the application of herbicides, but that of ladino clover (Trifolium repens) was significantly affected by glyphosate and paraquat. It was found that glyphosate and paraquat have no apparent soil residual activity or pre-emergence effect when sprayed 30 to 60 days before sowing. Dry matter yield of pasture species on the herbicide treatments was significantly higher than that on the unsprayed treatments. The highest yield was obtained from the 1.8kg a.i.$ha^{-1}$ rate of glyphosate 45 days before sowing. Botanical analysis at the final cut showed that the shrubs and native grass of original site were reduced to 5% by glyphosate application, but those on the unsprayed control were still 51%. Crude protein content and in vitro dry matter digestibility of herbage on the herbicide treatments were higher than those on the unsprayed treatments. Results indicated that glyphosate was more effective to control resident shrubs and grass than paraquat, and good establishment and higher yield of surface-sown pasture species can be obtained by spraying 1.8 to 2.8kg a.i.$ha^{-1}$ of glyphosate, 30 to 45 days before sowing.

• Journal for History of Mathematics
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• v.25 no.4
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• pp.53-67
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• 2012

Today, it is necessary to calculate orbits with high accuracy in space flight. The key words of Poincar$\acute{e}$ in celestial mechanics are periodic solutions, invariant integrals, asymptotic solutions, characteristic exponents and the non existence of new single-valued integrals. Poincar$\acute{e}$ define an invariant integral of the system as the form which maintains a constant value at all time $t$, where the integration is taken over the arc of a curve and $Y_i$ are some functions of $x$, and extend 2 dimension and 3 dimension. Eigenvalues are classified as the form of trajectories, as corresponding to nodes, foci, saddle points and center. In periodic solutions, the stability of periodic solutions is dependent on the properties of their characteristic exponents. Poincar$\acute{e}$ called bifurcation that is the possibility of existence of chaotic orbit in planetary motion. Existence of near exceptional trajectories as Hadamard's accounts, says that there are probabilistic orbits. In this context we study the eigenvalue problem in early 20th century in three body problem by analyzing the works of Darwin, Bruns, Gyld$\acute{e}$n, Sundman, Hill, Lyapunov, Birkhoff, Painlev$\acute{e}$ and Hadamard.

• Journal of The Geomorphological Association of Korea
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• v.21 no.4
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• pp.19-40
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• 2014

Rock rebound values and chemical compositions of Gamak island at Sangha, Gochang, Jeollabuk do are analysed as a part of geomorphic survey of that area. Some corestones are formed by deep weathering found from the summit of rock mass of Gamak island, while the rocks a part of weathering front are exposed at the foot of the island. Rebound values of rock increase toward coastal plain, so summit would be weak in resistance to erosion. It can be assumed that chemical weathering is more active at the summit by the chemical index of alteration and changes in chemical composition ratio. However it should be mentioned that the samples are taken from the surface of the rock mass that more fresh part will be exposed when the weathered parts are removed. The chemical composition and CIA values of the polygonal cracks found from on the surface of weathering rind showed that this part has values between those of the summit and the footslope. The bottom of weathering rind with polygonal cracks has higher CIA value than those of the surface. Though it supports the result from the Bisul Mt., there also difference in the ratio of SiO2. It looks caused by the difference in weathering environment and chemical difference in parent rock. In summary Gamak island is the remnants of weathering front after removal of weathered material. The removal processes are more active at the footslope where the coastal processes are stronger than the summit.