• Journal of Technologic Dentistry
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• v.21 no.1
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• pp.97-114
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• 1999

The first function of occlusion is mastication. Therefore the functional restoration of occlusal surface is very important. The restoration of occlusal surface is three method as wax bite technique, F.G.P. technique, cone technique. Many dental technician is using compound method. I have knew common point on each teeth during I have waxing up wax pattern. So I studied on the design waxup technique for maxillary molar occlusion. The results of the study were as follows ; 1. The dam wax up method can restore axial contour of teeth very easy and make short working time of wax pattern. 2. The height of dam must be same with cusp of adjacent teeth. 3. Automatically the contour of tooth is appeared if the contour of dam is relationship with cuspid line of adjacent teeth. 4. The height of contour of buccal, lingual surface is formed natural curve to add fluid wax by gravitation. 5. The development groove of Maxillary premolar is appeared V form. 6. The development groove of Maxillary molar is appeared W form. 7. The embrasure is formed to carve around contact point area as round convex. It affects to axial form of tooth. 8. I was knew that the lingual groove and stuart's groove of molar runs parallel with oblique ridge. 9. The buccal groove of molar is formed parallel with direction of teeth arrangement.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.6
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• pp.133-144
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• 2010

The objective of this planning proposal is to rehabilitate the urban stream which has been ecologically disturbed in the urban process. The experimental stream, Su-am stream located in Anyang City is typical urban stream in adjacent land use and the spatial condition. The stream in the watershed context, is the second tributary of Han River, in the Anyangcheon watershed. The Characteristics of the stream reach were analyzed by the river corridor survey. In the conceptual phase, Rehabilitation Programs were established based on the hydrological, ecological and spatial characteristics of the stream. Spatial zoning concept according to the characteristics of the stream and adjacent land use, was suggested 4 types of zoning; ecological preservation zone, natural landscape zone, neighborhood water-friendly zone and CBD water-friendly zone. Implementation Practices can be summarized as follow: For The longitudinal river continuum, some In-stream practices were suggested and implemented; such as channel alignment, step & pool, pool & riffle and low-flow channel bank. For latitudinal continuum and intimate spatial relationship between Sam-duk Park & Su-am stream, gentle sloped bank was planned and implemented. After stream improvement & ecological Implementation, follow-up monitoring and adaptive management programs will be a meaningful process for ecological rehabilitation.

• Journal of Soil and Groundwater Environment
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• v.17 no.4
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• pp.19-26
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• 2012

The influence of operation time on electrokinetic restoration was investigated to remove salts from sulfate-accumulated greenhouse soil. Operation time is directly related to the process cost, therefore, we determined the relationship between operation time and removal of salts. Nitrate and sodium were removed almost completely within 2 weeks, chloride and calcium was removed in proportion to the operation time. Sulfate was accumulated at the center of anode and cathode. The soil electrical conductivity (EC), an indicator for soil salinity, showed similar shape with the residual sulfate after electrokinetic treatment. The soil EC was not changed after 2 weeks, however, the energy consumption increased with operation time. Based on the experimental results, most salts except sulfate were removed within 2 weeks, but sulfate was not removed during same time period. For the further removal of sulfate, longer operation time is in need.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.5
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• pp.59-76
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• 2022

This study was conducted to investigated woody species community classification and understory vegetation characteristics of Abies nephrolepis forest in Mt. Gyebang and Mt. Odae designated as Protected Area for Forest Genetic Resource Conservation and National Park. Vascular plants were surveyed as following; 55 family, 148 species, 3 sub species, 14 variety, 2 form 167 taxa. As an analysis of the species estimator of Jackknife 1, 29 survey plots could be representative of vegetation in study site. Results of the woody species, 3 communities were divided by cluster analysis(A=Abies nephrolepis-Tilia amurensis, B=Betula ermanii-Abies nephrolepis, C=Quercus mongolica-Abies nephrolepis). Using MRPP-test, there were significant differences between the communities indicating analysis of the appropriate group classification(p<0.01). The basal area and altitude were analyzed by negative relationship for NMS ordination. By analyzing plexus diagram of woody species, Acer pseudosieboldianum is strong associated with Quercus mongolica and Rhododendron schlippenbachii. Magnolia sieboldii is strong associated with Acer pictum subsp. mono etc.

• Korean Journal of Environment and Ecology
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• v.28 no.2
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• pp.123-127
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• 2014

The red fox (Vulpes vulpes) is currently identified as a restoration target species, because it is listed as level 1 in the Korean National Park Service's endangered species list. The present research was conducted to investigate the basic behavioral patterns distribution of red foxes. For this study, red foxes under semi-natural conditions were observed and recorded from May 2012 to April 2013. The results revealed that the activities of the red foxes began at $16:59{\pm}01:20t$ and ended at an average time of $05:50{\pm}03:02t$. The males began and ended their activities earlier than their female counterparts. Among the seasonal activity durations, the longest activity duration was observed in summer with activity of 14 hours and 5 minutes, while the shortest activity duration was observed in winter with activity periods of 10 hours and 11 minutes. Generally, the red foxes exhibited a nocturnal behavioral pattern; the activity start time of the foxes was influenced by the sunset time. However, the activity end time showed no relationship with the sunrise time. The frequency of daily feeding activity ranged from one to eight times per day, with the males ($2.40{\pm}1.66$) exhibiting higher frequency than their female counterparts ($1.87{\pm}1.24$). The feeding activity peaked in November (average, 3.52 times per day) and was lowest in January (average, 1.28 times per day). Both males and females engaged in daily drinking activity (average, $2.03{\pm}1.296$ times per day). Thus, the increase in the frequency of the feeding activity is related to increase in the frequency of the drinking activity. Although the present research was conducted under semi-natural condition, the findings will be useful for the daily specification management of the species, monitoring of the released foxes, and habitat management based on the behavioral characteristics of the species.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.112-120
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• 2005

This study was done to evaluate whether there were any differences in microleakage of class V composite restorations according to restoration site and cavity size. Total sixty-four restorations were made in molar teeth using Esthet-X. Small ($2\;{\times}\;2\;{\times}\;1.5\;mm$) and large ($4{\times}2{\times}1.5\;mm$) restorations were made at the buccal/lingual surface and the proximal surface each. After 1,000 times of thermocycling ($5^{\circ}\;-\;55^{\circ}C$), resin replica was made and the percentage of marginal gap to the whole periphery of the restoration was estimated from SEM evaluation. Thermocycled tooth was dye penetrated with $50\%$ silver nitrate solution. After imbedding in an auto-curing resin, it was serially ground with a thickness of 0.25 mm. Volumetric microleakage was estimated after reconstructing three dimensionally. Two-way ANOVA and independent T-test for dye volume, Mann-Whitney U test for the percentage of marginal gap, Spearman's rho test for the relationship between two techniques were used, The results were as follows : 1. The site and size of the restoration affected on the microleakage of restoration. Namely, much more leakage was seen in the proximal and the large restorations rather than the buccal/lingual and the small restorations. 2. Close relationship was found between two techniques (Correlation coefficient = 0.614/ P = 0.000). Within the limits of this study, it was noted that proximal and the large restorations leaked more than buccal/lingual and the small restorations. Therefore, it should be strictly recommended large exposure of margins should be avoided by reducing unnecessary tooth reduction.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.3
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• pp.46-62
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• 2010

This study was conducted to understand the water and soil properties to propose the promotion of vegetation environment at farm pond depression. We selected 8 palustrine wetlands from agricultural area after consideration of human interference, surround land use, and size of area. Water quality analysis showed that the average SS, T-N, T-P were over the limit of agricultural water quality standard level at some sites. The cause for deterioration of water quality is supposed by the long-term stagnation of water in palustrine wetland. The recommended measures to improve water quality are as follows; improving water circulation by connecting with nearby natural water, preventing oxygen depletion by dredging deposit, lowering down T-N and T-P by removing autumn plants, preventing inflow of phosphorus in fertilizer ingredients which is the main cause for high T-P. The soil contamination of the surveyed area was about the same level of average heavy metal contents in soils from 2,010 paddy fields in Korea, which was much lower than soil contamination standards. As for soil texture, sand content was 40~90% and clay content was less than 20%. The content of silt and clay in soil from community of floating-leaved:submerged hydrophytes and community of emergent hydrophytes was higher that of soil from community of hygrophytes, and the content of sand in soil from community of hygrophytes was 10% higher than underwater soil. In terms of bulk density, the average was 0.24~0.96g/$cm^3$, which was quite low, because of high content of peat and organic matter in soil of the surveyed area. As for the average content of organic matter, community of floating-leaved:submerged hydrophytes was 18.25g/kg, community of emergent hydrophytes was 16.88g/kg, and community of hydrophytes was 25.63g/kg. The range of content of T-N in soil of community of floating-leaved；submerged hydrophytes was 0.022~0.307%, and that of community of emergent hydrophytes was 0.029~0.681% and that of community of hydrophytes was 0.088~0.325%. Apart from three sites in the surveyed area, most parts were over the standards or below the standard. After this study, we will conduct and discuss the relationship between vegetation characteristics and environments, which will be used of the best practical management and restoration of wetland.

• Journal of Korea Water Resources Association
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• v.48 no.3
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• pp.169-183
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• 2015

As a basic work for river restoration, analysis on fluvial geomorphological characteristics is made using past and present data to understand close-to-nature geomorphic status. The Miho and the Naesung Rivers are targets of this study. Fluvial geomorphic variables including valley-floor width, sinuosity, bankfull width, channel gradient, bed material size, bankfull discharge and unit stream power are evaluated with dominant processes. Though common sand-bed rivers with similar catchment area, the Miho and the Naesung Rivers are different in terms of valley-floor width, channel shape variables and dominant processes related with longitudinal location. In addition, analyses on interrelationship among the geomorphological variables are carried. Bankfull width is shown to be proportional to bankfull discharge, as is in a rough agreement with the previous studies. Relationship of bankfull discharge and channel gradient shows meandering and braiding are prevalent in the Miho River, whereas the most of the sub-reaches of the Naesung River fall to braiding. Relationship of channel gradient with width-depth ratio indicates dune-ripple processes are dominant in the Miho River, while the Naesung River shows longitudinal diversity from braiding in the downstream sub-reaches to riffle-pool and plane-bed along the upper ones. Analyses based on the past data on a river in a close-to-nature status are thought to be rather reasonable in comparison with those on the same river in a engineered condition.

• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.873-883
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• 2015

From August 2012 to April 2013, the ichthyofauna and post-restoration properties of Yangjae stream were investigated. A total of 1,503 fish of 2 forms, 16 species and 5 families were studied during the survey period. A survey of the distribution of freshwater fish inhabiting Yangjae stream after restoration of the stream showed large populations of Zacco platypus and Rhynchocypris oxycephalus. From the frequency distribution of the total length for the Zacco platypus population inhabiting Yangjae stream, it was estimated that there are 4 distinct age groups, with an abundance of the 27-63 mm (Age $0^+$) category accounting for 51.3% of the population. The regression coefficient (b) for the length-weight relationship in Zacco platypus was 3.27, while the slope of the condition factor was positive, demonstrating that stable growth conditions are being maintained. Analysis of tolerance and trophic guilds showed a decrease in the numbers of sensitive species and insectivore species further downstream, and an increase in tolerant species and omnivore species. Principal component analysis using community indices and indices of biotic integrity (IBI) showed that there were differences according to the survey time: the first and second surveys showed major changes on certain single species populations while during the third survey, it was analyzed that the populations of various types of fish had established balance.

• Korean Journal of Environment and Ecology
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• v.30 no.3
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• pp.320-327
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• 2016

Intertidal zone has been restored by the Sihwa Lake tidal power plant is operating in 2012. After restoration, to check the difference of bird group's community change out, the examination has been carried out from 2009 to 2014 when sea dike sluicer runs, the intertidal zone area was increased to $20.3km^2$ after restoring in $5.3km^2$. There was no significant difference in the number of individuals congestion of the whole, but the results of analysis of the differences between the six bird group by number of individuals, it showed a significant difference in Diving ducks(p = 0.237) the Herons (p<0.001), Swans and Geese (p<0.01), Dabbling ducks (p<0.001), showed a significant difference in the Shore birds (p<0.001) gulls (p<0.001) except for diving of ducks. Sihwa Lake intertidal zone was only just been restored, but environment and the improvement of benthic ecosystem has been carried out, It is determined that waterfowls that living based on intertidal zone are also affected. This study is a good example of the restoration of the intertidal zone that disappeared, which hard to find a similar case. It will be utilized as basic data of ecological monitoring for the conservation and management of the future of the intertidal zone later.