• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.126-140
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• 1977

Present studies were carried out for breeding cold resistant clones of Citrus, improving overwintering techniques of Citrus in Jeju island as well as other southern region, Result obtained were as follows 1. In the vinyl house covered with two sheets of straw mat, 12 indivuals were found as non-injury and 15 were slightly injured by leaf freeging test at $-9^{\circ}C$ for 2 hours treatment. 2. In the condition of vinyl house covered with straw mat and viny film mulching and heat-in by sun-light, the inside temperature of vinyl house were not lowered below $-3^{\circ}C$ and the ground temperatura in vinyl house keeps above $0^{\circ}C$ during winter though outdoor temperature were lower by $-15^{\circ}C$(Daejeon area). 3. The vinyl tunnel inside the vinyl house and vinyl film mulching on ground position showed greater effectiveness for preventing heat loss from house but there were no significant difference between the color of vinyl film covered the tunnel. 4. In the vertical distribution of maximum temperature in vinyl house, the upper space was slightly higher than the lower position at high temperature condition, while minimum temperature was distributed as higher as the middle position, ground surface and upper position in order at low temperature condition 5. In the horizontal distribution of temperature in vinyl house, ground and surface-temperature of north side was lower than the other sides, and citrus planted within 30cm from north side wall died by cold injury and in the other side near wall appeared slight symptom of cold injury. 6. The insulating trench ($30{\times}30{\times}30cm$) packed with straw bundle installed under north wall might be effective to prevent heat loss of ground temperature. 7. In cloudy and snowy day, the temperature difference between indoor and outdoor were less, and the indoor temperature were maintained highly during night due to the effect of prevention of heat loss. 8. The highest temperature in a day was observed at about P.M. 3 both inside and outside of vinyl house and the lowest temperature was observed at about A.M. 6. The difference between the highest and lowest temperature of indoor in a sunny day was $19^{\circ}C$, compared with $9^{\circ}C$ on a cloudy or snowy day in late November. Especially, lowering of temperature in a snowy day was so less that the curve of temperature change was comparatively constant, 9. If the effective methods of citrus cultivation in vinyl house with improved clone such as hardiness. semi-dwarf and spur type are applied, it might be possible to cultivate the citrus tree safely in Jeju island as well as other southern rejion and to magnity the cultivation of citrus tree.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.153-162
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• 2014

Purpose: This study was assessed to investigate the change of subjective and/or objective symptoms and the light transmittance of lens caused by the use longer than recommended wearing time of daily disposable circle contact lenses (circle lens) in dry eyes. Methods: Three daily disposable circle lenses made of etafilcon A, hilafilcon B, and nelfilcon A were applied on 30 dry eyes with smaller tear volume than normal eyes in their twenties free from any eye diseases by when subjects complained any kind of discomfort. On the first and the last days of lens wearing, subjective discomfort, blinking rate, lens centration on corneal surface and visible light transmittance of lens were recorded at every case and compared. Results: The circle lens wearers complained subjective discomfort and quit the lens wearing when they wore the circle lens longer than 10 hours even though there were some difference according to the lens materials of daily disposable circle lens. However, around 20% of dry eyes could wear the circle lens made of non-ionic materials longer than 40 hours. Dry eyes showed most sensitive feeling of subjective discomfort against the circle lens made of etafilcon A among three different lens materials. On the last day of lens wearing, the representative subjective discomforts were irritation, stiffness, dryness and tiredness. When the subjects wore circle lens more than the recommended time, blinking rate was significantly increased about 20~30% regardless of lens materials when it compared with the values right after lens wearing. On the last day of lens wearing, the vertical direction of lens centration was shifted to pupil center however, its distribution in horizontal direction was wide compared with the distribution right after lens wearing. Especially, the centration of etafilcon A lens was unstable. Furthermore, the visible light transmittance of 3 different circle lenses in dry eyes has significantly been reduced around 15% averaged. Conclusions: From these results, it was known that the increase of dryness and stiffness caused by overusage of daily disposable circle lens induced excess irritation and decreased visible light transmittance and caused significant more blinking, which provoked lens decentration. It was also revealed that dry eyes showed sensitive reaction subjectively and objectively against the overusage of circle lens made of high water content/ionic lens material even there were some difference of the degree depending on the individual and the lens material. Thus, this research can be suggested as the basic reference for the education about some unexpected problems and the side effect caused by the wearing of circle lens in dry eyes.

• Korean Journal of Remote Sensing
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• v.28 no.4
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• pp.393-407
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• 2012

This study focuses on the correction of topographic effects caused by a combination of solar elevation and azimuth, and topographic relief in single optical remote sensing imagery, and by a combination of changes in position of the sun and topographic relief in comparative analysis of multi-temporal imageries. For the Jeju Island, Republic of Korea, where Mt. Halla and various cinder cones are located, a Landsat 7 ETM+ imagery and ASTER GDEM data were used to normalize the topographic effects on the imagery, using two topographic normalization methods: cosine correction assuming a Lambertian condition and assuming a non-Lambertian c-correction, with kernel sizes of $3{\times}3$, $5{\times}5$, $7{\times}7$, and $9{\times}9$ pixels. The effects of each correction method and kernel size were then evaluated. The c-correction with a kernel size of $7{\times}7$ produced the best result in the case of a land area with various land-cover types. For a land-cover type of forest extracted from an unsupervised classification result using the ISODATA method, the c-correction with a kernel size of $9{\times}9$ produced the best result, and this topographic normalization for a single land cover type yielded better compensation for topographic effects than in the case of an area with various land-cover types. In applying the relative radiometric normalization to topographically normalized three multi-temporal imageries, more invariant spectral reflectance was obtained for infrared bands and the spectral reflectance patterns were preserved in visible bands, compared with un-normalized imageries. The results show that c-correction considering the remaining reflectance energy from adjacent topography or imperfect atmospheric correction yielded superior normalization results than cosine correction. The normalization results were also improved by increasing the kernel size to compensate for vertical and horizontal errors, and for displacement between satellite imagery and ASTER GDEM.

• Economic and Environmental Geology
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• v.32 no.4
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• pp.323-337
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• 1999

Late Cretaceous to early Tertiary volcanic rocks in the Kyongsang basin exhibit high-K calc-alkaline characteristics, and originated from the magmatism related genetically to subduction of Kula-Pacific plate. They represent HFSE depletion and LlLE enrichment characteristics as shown by magmas related to subduction. Early studies on the depth of magma generation has been estimated as 180-230 km based on K-h relation should be reevaluated, because the depth of peridotite partial melting with 0.4 wt. % water is 80-120 km at subduction zone, and subducting slab in premature arc can melted even lower than 70 km. Moreover the increase of potassium contents depends on either contamination of crustal material and fluids of subducting slab or low degree of partial melting. If the inclination of subduction zone is 30 degrees and the depth to the Benioff zone is 180-230 km, the calculated distance between the volcanic zone and trench axis would be 310-400 km. It is unlikely because the distance between the Kyongsang basin and trench during late Cretaceous to early Tertiary is closer than this value and not comparable with generally-accepted models in subduction zone magmatism. $K_{55}$ of the volcanics in the Kyongsang basin is 0.3-2.3 wt.% and the average indicate that the depth ranges between 80-170 km on the diagram of Marsh, Carmichael (1974). Fractionation from garnet lherzolite, assumed the depth of 180-230km, is not consistent with the REE patterns of the volcanoes in the Kyongsang basin. Futhermore, the range of depth suggested by many workers, who studied magmatism related to subduction, imply shallower than this depth. Crustal thickness calculated by the content of CaO and $Na_2O$ is about 30 km and about 35 km, respectively. Paleo-crustal thickness during late Cretaceous to early Tertiary times in the Kyongsang basin inferred about 30 km calculated by La/Sm versus LaJYb data, which is also supported by many previous studies.

• Journal of Wetlands Research
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• v.2 no.1
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• pp.31-40
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• 2000

The flora, vegetation structure and physico-chemical characteristics of surface sediment were investigated in Paksil-nup wetland of Hapcheon-gun, Gyeongsangnam-do, Korea in 1990~1998. Ranges of the surface sediment characteristics such as pH, conductivity, organic matter, total nitrogen, available phosphorus, exchangeable K, exchangeable Ca, exchangeable Mg, and exchangeable Na were 4.36~4.34, $19.0{\sim}1260.0\;{\mu}mho\;cm^{-1}$, 0.01~6.35%, 0.001~0.14%, 0.01~0.31 mg/l00g, 1.01~13.98 ppm, 16.75~143.80 ppm, 0.93~14.85 ppm and 0.21~3.86 ppm, respectively. Percentages of the particle size such as sand, silt, and clay were 13.0~93.3%, 5.4~71.7%, and 0.5~37.5%, respectively. The flora of the study area was composed of 72 families, 182 genera, 223 species, 36 varieties and 2 form or total 261 kinds, and those were 45 kinds of vascular hydrophytes and 216 kinds of vascular hygrophytes. The life form of vascular hydrophytes was classified as 27 kinds (60%) of emergent plants, 8 kinds (18%) of submerged plants, 6 kinds (13%) of free-floating plants and 4 kinds (9%) of floating-leaved plants, respectively. The importance value of Salix nipponica was highest as 123.78 in the shrub and tree layers, and that of Trapa japonica was highest as 16.69 in the herb layer. The vegetation type was divided into two groups according to the association analysis. The vegetation of the littoral zone was classified into 7 associations according to the cluster analysis based on the coverage data. These results showed significant differences with those of stand ordination by correspondence analysis based on the species composition and by PCA based on the sediment properties. Factors affecting the distribution of the vascular hydrophytes and hygrophytes were the gradient of particle size, altitude, and water depth.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.2
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• pp.103-110
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• 2005

Binocular vision had a short history in Korea. As there were many near works in these days, the needs about comparative study have been increased. There was related to both refractive error and binocular anomalies, but it is difficult to applying for binocular vision expected findings in itself due to the fact that Korean differ from foreigner. Objects were 100 adults in 18-36 years old ages, The test was Von Gaefe method and used aparatus was phoropter(Shinnippon VT10)and visual chart(Shinnippon CT30). According to interview results was that symptom in near works were headaches 28.0%, blinking 27.3%, red eye 25.1%, eyepain 15.6%, watering 15.3%, itch 12.2%, photophobia 8.5% and eye strain 7.4%. A people who have above ${\pm}0.50$ D refractive error in total objectives (100-male 45/female 55) were classified into ametropia. There was a results such as emmetropia (12.0%), ametropia(88.0%), exophoria(32.0%), esophoria(12.0%). Far negative relative convergence were that in case of high 43.0%, in case of low 7.0%. Far positive relative convergence were that in case of high 15.0%, in case of low 38.0%. Near phoria was exophoria(32.0%), esophoria(12.0%). Near negative relative convergence were that in case of high 23.0%, in case of low 38.0%. Far positive relative convergence were that in case of high 29.0%, in case of low 23.0%. Near negative relative accommodation were that in case of high 10.0%, in case of low 14,0%, Far positive relative convergence were that in case of high 69.0%, in case of low 12.0%. Results were different from expected findings, and especially positive relative accommodation was very high, However, We suggest that the expected findings in Korea for several subjects must study in binocular function.

• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.405-414
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• 2008

To better understand the physical processes that control the high-latitude lower thermospheric dynamics, we analyze the divergence and vorticity of the high-latitude neutral wind field in the lower thermosphere during the southern summertime for different IMF conditions. For this study the National Center for Atmospheric Research Thermosphere-Ionosphere Electrodynamics General Circulation Model (NCAR-TIEG CM) is used. The analysis of the large-scale vorticity and divergence provides basic understanding flow configurations to help elucidate the momentum sources that ulti-mately determine the total wind field in the lower polar thermosphere and provides insight into the relative strengths of the different sources of momentum responsible for driving winds. The mean neutral wind pattern in the high-latitude lower thermosphere is dominated by rotational flow, imparted primarily through the ion drag force, rather than by divergent flow, imparted primarily through Joule and solar heating. The difference vorticity, obtained by subtracting values with zero IMF from those with non-zero IMF, in the high-latitude lower thermosphere is much larger than the difference divergence for all IMF conditions, indicating that a larger response of the thermospheric wind system to enhancement in the momentum input generating the rotational motion with elevated IMF than the corresponding energy input generating the divergent motion. the difference vorticity in the high-latitude lower thermosphere depends on the direction of the IMF. The difference vorticity for negative and positive $B_y$ shows positive and negative, respectively, at higher magnetic latitudes than $-70^{\circ}$. For negative $B_z$, the difference vorticities have positive in the dusk sector and negative in the dawn sector. The difference vorticities for positive $B_z$ have opposite sign. Negative IMF $B_z$ has a stronger effect on the vorticity than does positive $B_z$.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.109-118
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• 1999

Recently, transport parameters of conservative solutes such as KCl in a porous medium have been successfully determined using time domain reflectometry (TDR) . This study was initiated to Investigate the applicability of TDR technique to monitoring the fate of a heavy metal ion in a sandy soil and the distribution of its concentration along travel distance with time. A column test was conducted in a laboratory that consists of monitoring both resident and flux concentrations of $ZnCl_2$in a sandy soil under a breakthrough condition. A tracer of $ZnCl_2$(10 g/L) was injected onto the top surface of the sample as pulse type as soon as a steady-state condition was achieved. Time-series measurements of resistance and electrical conductivity were performed at 10 cm and 20 cm of distances from the inlet boundary by horizontal-positioning of parallel TDR metallic rods and using an EC-meter for the effluent exiting the bottom boundary respectively. In addition. Zn ions of the effluent were analyzed by ICP-AES. Since the mode and position of concentration detected by TDR and effluent were different, comparison between ICP analysis and TDR-detected concentration was made by predicting flux concentration using CDE model accommodating a decay constant with the transport parameters obtained from the resident concentrations. The experimental results showed that the resident concentration resulted in earlier and higher peak than the flux concentration obtained by EC-meter, implying the homogeneity of the packed sandy soil. A close agreement was found between the predicted from the transport parameters obtained by TDR and the measured $ZnCl_2$concentration. This indicates that TDR technique can also be applied to monitoring heavy metal concentrations in the soil once that a decay constant is obtained for a given soil.

• The Journal of the Petrological Society of Korea
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• v.14 no.2 s.40
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• pp.93-107
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• 2005

We determined $^{40}Ar/^{39}Ar$ ages of the Tertiary dike swarms and volcanic rocks distributed in the SE Korea where the most prevalent crustal-deformation and volcanism occurred during the period. In previous study, it was disclosed that the mafic dike swarms on both sides (east and west) of the Yeonil Tectonic Line (YTL) were originated from a same magma although they are consistently aligned with different intrusion directions of NS and NE, respectively. Ages of the mafic dike swarms of this study are $47.3\pm0.8Ma$ and $48.0\pm1.3Ma$, respectively and confirm such conclusion. These facts clarify that the YTL acted as a westernmost limit of the crustal deformation, especially clockwise crust-rotation, during the Miocene. Frequent occurrence of basic dikes indicate strongly that the southeastern part of the Korean Peninsula was under E-W extensional stress field at about 48 Ma, intimately related to the India-Asia collision and subsequent sudden change of the Pacific Plate motion. The ages of the uncommonly appearing intermediate and felsic dikes were determined as $55.9\pm1.5Ma$ and $53.0\pm1.0Ma$, respectively. Ages of the andesitic lava of the Hyodongri Volcanics, the dacitic lava of the Yongdongri Tuff, and dacitic rocks intruding and covering the Churyeong Breccia were determined as $24.0\pm0.5Ma,\;21.6\pm0.4Ma$, $21.8\pm0.1Ma,\;and\;22.0\pm0.5Ma$ respectively. The ages from the volcanics agrees well with the stratigraphy established by the latest field survey, which confirms that the $andesitic\~dacitic$ volcanism was followed by the basaltic volcanism during the Early Miocene.

• Journal of the Korean earth science society
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• v.33 no.3
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• pp.259-268
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• 2012

To investigate the fluctuation of marine aerosol number concentration at each different size with vertical winds in ocean area, aerosol particles and vertical wind components were measured in the Ieodo Ocean Research Station, which is located to 419 km southwest of Marado, the southernmost island of Korea, from 8 to 22 June 2009. The Laser Particle Counter (LPC) and ultrasonic anemometer were used to measure the number of aerosol particles and vertical wind speed. Surface weather chart, NCEP/NCAR reanalysis data and sounding data were used to analyze the synoptic condition. The distribution of aerosol number concentration had a large fluctuation of bigger particles more than 1.0 ${\mu}m$ in diameter by vertical wind speed during precipitation. The aerosol particles larger than 1.0 ${\mu}m$ in diameter increased as the wind changed from downward to upward during precipitation. The aerosol number concentration of bigger size than 1.0 ${\mu}m$ in diameter increased about 5 times when vertical velocity was about 0.4 $ms^{-1}$. In addition, the accumulation and coarse mode aerosol number concentration decreased about 45% and 92%, respectively compared to concentrations during precipitation period. It is considered that vertical wind plays an important role for the increasing of coarse mode aerosol number concentration compared to the large aerosol particles sufficiently removed by the scavenging effect of horizontal winds. Therefore, the upward vertical winds highly contribute to the formation and increase in aerosol number concentration below oceanic boundary layer.