• Journal of Korean Ophthalmic Optics Society
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• v.15 no.4
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• pp.361-366
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• 2010

Purpose: HCD ion plating apparatus by hollow cathod discharge method was fabricated and TiN films were deposited on stainless steel by this apparatus with increasing in $N_2$ gas flow and the fine color changes of TiN films were analyzed. Methods: The spectroradiometer and spectrophotometer were used to observe optically the fine color changes of TiN thin films, and XPS was used to analyze the compositions of TiN thin films with increasing in $N_2$ gas flow. Results: The color coordinate of TiN thin film with $N_2$ 120 sccm gas flow showed (0.382, 0.372) which had the mixed colors of gold and silver, and the color coordinate changed to the increasing value of (x,y) with increasing in $N_2$ gas flow which indicated the deep gold color. It was found that the slopes of the reflectances at 550nm were increased with increasing in $N_2$ gas flow. And from the Ti scans using XPS, it was found that the peak heights of 455 eV derived from TiN composition were increased with increasing in $N_2$ gas flow, while the peak heights of 459 eV from $TiO_2$ composition were decreased. Conclusions: The results obtained above were that the color of TiN film with 120 sccm $N_2$ gas flow had been observed from the mixed color of silver and gold due to TiC, $N_2$, TiN on the surface and TiN, $N_2$ inside film, and the color of TiN films changed a deep gold color with increasing in $N_2$ gas flow due to increasing TiN composition.

• Korean Journal of Plant Taxonomy
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• v.41 no.1
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• pp.66-80
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• 2011

This study investigated the environmental factors and conducted a RAPD analysis for a better understanding of the environmental characteristics and regional genetic variation in samples from 18 different areas of Viola diamantiaca. The habitats are mostly located on the slopes of mountains facing north at an altitude ranging from 614 m to 1,462 m above sea level with angles of inclination ranging from 3 degrees to 30 degrees. A total of 268 vascular plant taxa are identified in 35 quadrates of 18 habitats. The importance value of V. diamantiaca is 11.58%, and four highly ranked species, Sasa borealis (5.61%), Meehania urticifolia (5.21%), Ainsliaea acerifolia (3.62%), Pseudostellaria palibiniana (3.60%) are considered to have an affinity with V. diamantiaca in their habitats. The degree of their average species diversity is 1.36, while this metric for their evenness and dominance are 0.89 and 0.07, respectively. The average field capacity of the soil is 25.99%, with organic matter at 17.47%, and the pH is 5.19. The soil texture was confirmed as sandy loam of eleven and loam of seven. The result of the RAPD analysis, among 78 bands amplified with a primer, 64 (84.6%) showed polymorphism. Eighteen populations could be classified into five groups with similarity coefficient values ranging from 0.53 to 0.86. The Mt. Jiri population, which is geographically segregated, shows basal branching within the 18 populations. Five populations, including two in the southern district in Gangwon-do and three in Chungcheongbuk-do, form a distinct clade. Four populations in the central district of Gangwon-do and Mt. Bohyeon in the Gyeongsangbuk-do clade form a sister to the clade containing two populations in Gyeonggi-do and five populations of the northern district in Gangwon-do. The Mt. Gariwang population is placed between the southern district and the central district in the Gangwon-do clades.

• Radiation Oncology Journal
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• v.5 no.1
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• pp.13-21
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• 1987

The effect of local hyperthermia of 41 to $43^{\circ}C$ for 30 minutes on radiosensitivity of normal tissue was studied utilizing jejunal crypt microcolony assay. Hyperthermia of this range enhanced the radiation effect and the effect was mainly additive without significant effect on the slopes of cell survival curves. At the isoeffect level of 20 microcolony formation, the thermal enhancement ratio was 1.02, 1.10 and 1.39 for $41^{\circ},\;42^{\circ}\;and\;43^{\circ}C$, respectively. The distribution of microcolony formation along the circumference of jejunum was not uniform, having more colonies around the mesenteric border, and this suggests the effect of uneven cooling by blood circulation.

• Journal of the Korean Society of Groundwater Environment
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• v.1 no.1
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• pp.23-32
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• 1994

To determine the apparent equilibrium constants, K$_{ad,app}$, for the adsorption reactions of trace metals on amorphous iron oxyhydroxide (AIO) in the Taebag coal mine area, time-adsorption and pH-adsorption experiments were performed for a selected bottom sediment mainly comprised of AIO from the study area. The results from the adsorption experiments indicate that most of the trace metals, except Pb, achieve equilibrium states with AIO and thus, the calculated K$_{ad,app}$ may represent the true apparent equilibrium constants. K$_{ad,app}$ and the stoichiometric coefficients of proton, x, of the adsorption reactions between the trace metals and AIO were respectively calculated from the intercepts and slopes of the regression lines of log($\Gamma$/ ［M］$_{aq}$)against pH provided by pH-adsorption experiments. The calculated K$_{ad,app}$ this study has the values of the range from 10$^{－4.5}$ to 10$^{2.75}$ , which is much different from the reported values by other investigators for simple experimental systems. K$_{ad,app}$ of this study is more or less close but not exactly pertinent to the estimated values for the other natural systems. It indicates that K$_{ad,app}$ for the adsorption reactions in the aquatic system in the study area is unique and thus should be determined befor the adsorption modelling. The calculated x of this study has the values of the range from -0.3 to 0.7, which is also much different from what most geochemists generally accept. The discrepancy in x may be due to the competition among different kinds of ionic species on the adsorption site or simulataneous occurrence of different kinds of adsorption reactions. The results from this study should help construct an appropriate adsorption model for the aquatic systems polluted by the coal mine drainage in the Taebag area. With the constructed model, one can describe the concentration variations of trace metals due to the adsorption in the system, which is an essential part of the investigation on the water quality affected by coal mine drainage in the Taebag coal field.

• Journal of Environmental Policy
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• v.8 no.1
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• pp.73-95
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• 2009

The fact that soil loss causing to increase muddy water and devastate an ecosystem has been appearing upon a hot social and environmental issues which should be solved. Soil losses are occurring in most agricultural areas with rainfall-induced runoff. It makes hydraulic structure unstable, causing environmental and economical problems because muddy water destroys ecosystem and causes intake water deterioration. One of three severe muddy water source areas in Soyanggang-dam watershed is Jawoon-ri region, located in Hongcheon county. In this area, many cash-crops are planted at illegally cultivated agricultural fields, which were virgin forest areas. The purpose of this study is to estimate soil loss with current land uses(including illegal cash-crop cultivation) and soil loss reduction with land use conversion from illegal cultivation back to forest. In this study, the Sediment Assessment Tool for Effective Erosion Control(SATEEC) ArcView GIS was utilized to assess soil erosion. If the illegally cultivated agricultural areas are converted back to forest, it would be expected to 17.42% reduction in soil loss. At the Jawoon-ri region, illegally cultivated agricultural areas located at over 30% and 15% slopes take 47.48 ha(30.83%) and 103.64 ha(67.29%) of illegally cultivated agricultural fields respectively. If all illegally cultivated agricultural fields are converted back to forest, it would be expected that 17.41% of soil erosion and sediment reduction, 10.86% reduction with forest conversion from 30% sloping illegally agricultural fields, and 16.15% reduction with forest conversion from 15% sloping illegally agricultural fields. Therefore, illegally cultivated agricultural fields located at these sloping areas need to be first converted back to forest to maximize reductions in soil loss reduction and muddy water outflow from the Jawoon-ri regions.

• Korean Chemical Engineering Research
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• v.52 no.3
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• pp.321-327
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• 2014

Polymer dispersed liquid crystal lenses of the cell gap of $11{\mu}m$ and $30{\mu}m$ were made from a uniformly dispersed mixture of 40 wt% NOA65 prepolymer - 60 wt% E7 liquid crystal with the variations of the additional photoinitiator. The photoinitiator, benzophenone of 5.0 wt% was originally in the commercial prepolymer NOA65. In this works, the influence of the benzophenone amount intentionally added in the commercial NOA65 on the electrical properties of polymer dispersed liquid crystal lens for smart electronic glasses. The additional quantities of the photoinitiator were 1, 2, 4, 8 and 16 wt% of the weight of NOA65 - E7 mixture. All the electro-optical properties of the sample with added benzophenone such as the driving voltage, the slope of the linear region, the response time and contrast ratio were more improved than that of commercial NOA65 only. These improvements were due to the increase of the average size of E7 liquid crystal droplets in the samples with the increase of the added benzophenon amount. The liquid crystal droplet size was increased from $5.3{\mu}m$ to $12.2{\mu}m$ when the photoinitiator was added from 0 wt% to 8 wt%. At the same concentration range of the photoinitiator, the driving voltage was ranged from 11.1 V to 17.3 V. The slopes of the linear region were in the range of 10.35~13.96 %T/V, which were more enhanced than that of NOA65 without the additional benzophenone. In particular, though the deteriorations by cell gap of $11{\mu}m$ were so effective to offset the influence of the added benzophenone for both rising and falling response time, it is confirmed that there were still somewhat improvement by the additional benzophenone. Response time and contrast ratios of all the samples with excess benzophenone were slightly enhanced.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.363-368
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• 2003

We have successfully developed a more effective algorithm to extract the lineament in the area covered by wide alluvial deposits characterized by a relatively narrow range of brightness in the Landsat TM image, while the currently used algorithm is limited to the mountainous areas. In the new algorithm, flat areas mainly consisting of alluvial deposits were selected using the Local Enhancement from the Digital Elevation Model (DEM). The aspect values were obtained by 3${\times}$3 moving windowing of Zevenbergen & Thorno's Method, and then the slopes of the study area were determined using the aspect values. After the lineament factors in the alluvial deposits were revealed by comparing the threshold values, the first rank lineament under the alluvial deposits were extracted using the Hough transform In order to extract the final lineament, the lowest points under the alluvial deposits in a given topographic section perpendicular to the first rank lineament were determined through the spline interpolation, and then the final lineament were chosen through Hough transform using the lowest points. The algorithm developed in this study enables us to observe a clearer lineament in the areas covered by much larger alluvial deposits compared with the results extracted using the conventional existing algorithm. There exists, however, some differences between the first rank lineament, obtained using the aspect and the slope, and the final lineament. This study shows that the new algorithm more effectively extracts the lineament in the area covered with wide alluvlal deposits than in the areas of converging slope, areas with narrow alluvial deposits or valleys.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.212-219
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• 2004

To minimize the danger of soil erosion and settle habitats earlier, afforestation, which vegetates bare slopes, is selected as an environmental recovering technology. Large portions of these areas often are suffered by a bad germination and growth inhibition of sprayed seeds. Afforested materials collected in the normal and damaged sites were not any big difference in chemical characteristics and biological response to ryegrass. But background soil of the damaged site has very low pH (3.6) and high contents of iron and aluminum compared with them of the normal sites. Both germination and root growth of ryegrass were inhibited severely in the water extracts of damaged soils, but not in the water extracts of normal sites. Groundwater collected nearby the damaged sites was very strong acidic (pH 33) and exhibited a high value of electrical conductivity and high contents of iron and aluminum. In the ground water, germinated ryegrass was scarcely grown. In Al standard solution, the root growth of ryegrass was inhibited over 50% in 0.5 mM in pH 3.5-4.5 and in 1.4 mM in pH 5.5, which seems to be related to $Al^{3+}$ activity in solution. In the ferric Fe ($Fe^{3+}$) standard solution, ryegrass growth was inhibited over 50% in the concentration of 14-19 mM in root and 23-25 mM in shoot. This strong tolerance of ryegrass to $Fe^{3+}$ might be concerned with the very low activity of $Fe^{3+}$ at pH 3.5-5.5. In contrast, ryegrass responded very sensitively to ferrous Fe ion ($Fe^{2+}$), especially in root growth: $Fe^{2+}$ concentrations corresponding to 50% growth reduction were 0.3-0.4 mM at pH 3.5-5.5 in roots. This high growth inhibition should be related to the high ion activity of $Fe^{2+}$ irrespective of different pH conditions. In conclusion, low pH and high contents of $Fe^{2+}$ and aluminum seem to be caused by pyrite and be closely related to the growth inhibition of ryegrass seeded in afforested area.

• Journal of Environmental Policy
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• v.11 no.3
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• pp.25-47
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• 2012

This research is to suggest an ecological management methods by classification of biotope type and its mapping for Tricholoma matsutake. The target area was construction site of the East Hongchun - Yangyang Highway (Yangyang section) where massive production of Tricholoma matsutakes is in place. Specifically, the 700 m long range of area around the road route, Yangyang section, which is over a total area of $19,79km^2$. The flow of this research was as follows: first studied were the characteristics of the Yangyang Tricholoma matsutakes; second, reviews on previous studies on Tricholoma matsutakes; third, the formulation of standards and processes of biotope type considering Tricholoma matsutake production; and fourth, mapping of biotope considering the production area of Tricholoma matsutake. In 24.77% of the region, slope angle measured $30{\sim}40^{\circ}C$, which is suitable for Tricholoma matsutake production. Also, 17.44% of the region had southward vegetation structures, and as for the Pinus densiflora; 26.00% had average receipts; the tree ages was $38{\pm}8.34$ years; and the average density of canopy layer was $9.55{\pm}4.89/100m^2$. The soil acidity (pH) values of 5.0 to 5.6(47.96%) > 5.6 to 7.0(42.90%) > 4.0 to 5.0(9.14%) were slightly high for Tricholoma matsutake growth; but 57.10% of the area had a soil pH of 4.0-5.6. The organic horizon (A0 layer) was $3.39{\pm}2.14cm$, and the mean depths were 4-6cm(78.03%) > 0-2cm(18.10%) > 2-4cm(3.87%). Based on the results of previous studies and field researches on the presence of vegetation (the pine dominance ratio), the topographic structure (the terrain characteristics and slopes), the receipt, the soil structure (the soil acidity and the organic layers interposed between the depths), and the vegetation density, six clusters based on the identified types of biotopes are produced in this paper. Area of distribution according to the type of biotope was Tricholoma matsutake of the potential-production (II) biotope (32.86%) > Tricholoma matsutake of the inadequate-production biotope (22.17%) > Tricholoma matsutake of the adequate (II)-production biotope (17.79%) > Tricholoma matsutake of the adequate (I)-production biotope (14.86%) > Tricholoma matsutake of the potential-production (I) biotope (9.77%) > Tricholoma matsutake of the produced biotope (2.55%).

• Journal of Aquaculture
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• v.9 no.1
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• pp.43-55
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• 1996

The experiment was performed to evaluate the possibility of utilizing underground sea water for the seed production of tiger puffer, Takifugu rubripes. For this purpose, the effects of 6 different salinities (3.5, 7.0, 14.0, 20.0, 27.0, $33.0\%_{\circ}$) were determined based on the hatching rate of fertilized eggs, survival rate and the amount of food consumed by hatched larvae, where as the effects of 3 different salinities (20.0, 27.0, $33.0\%_{\circ}$) were also examined with rearing tiger puffer juvenile ($4.29{\pm}0.50$ cm in total length) for 50 days in the closed recirculating water system. As a results, either the hatching or the survival rate of more than $70.0\%$ were obtained from the fertilized eggs reared at the salinity of 27.0 to $33.0\%_{\circ}$, the early hatched larvae at 27.0 to $33.0\%_{\circ}$, and the 10-day-old larvae at 20 to $33.0\%_{\circ}$. At three different salinities, the survival rate of 20-day- and 30-day-old larvae turned out to be $89.0\%$ and $92.5\%$, respectively. The salinity for maximum food intake thus appeared to be from 27.0 to $33.0\%_{\circ}$. In this condition, 20-day-old hatched larvae consumed $323\~342$ Artemia nauplii and 30-day-old hatched larvae ate $1,559\~1,5791$ A. nauplii. The highest growth rate of fingerlings were observed at the salinity $27\%$ and followed by 33.0 and $20.0\%_{\circ}$, respectively. The relationship between the days of rearing (X) and the total length (Y) of the fingerlings were as follows : $33.0\%_{\circ}$ group : Y=0.107X-2.532 (r=0.982) $27.0\%_{\circ}$ group : Y=0.116X-3.195 (r=0.975) $20.0\%_{\circ}$ group : Y=0.116X-2.693 (r=0.987) The slopes of regression line estimated from $27.0\%_{\circ}$ and $33.0\%_{\circ}$ groups were significantly different from that of $20.0\%_{\circ}$ group.