• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.44-54
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• 2001

This study was conducted to estimate microclimate of natural deciduous forest in national forest of Pyungchang, Kangwon province and to investigate the effects of the microclimatic conditions on the periodic annual increment of diameter by site types. In this study, site was first classified by nine types considering both elevation (higher than 1,000 m, 700∼1,000 m, and lower than 700 m) and topographical conditions (ridge, slope and valley). For each of site types, diameter growth was measured by using increment borer and periodic annual increment of diameter was then analyzed. A topoclimatological technique, for estimating microclimatic conditions, which make use of empirical relationships between the topographical factor and the climatic normals in the study area was applied to produce monthly mean, maximum and minimum temperatures, relative humidity, precipitation and hours of sunshine. From these monthly estimtes, 17 weather variables such as warmth index, coldness index, index of aridity etc. which affect the diameter growth were computed for each of site types. The periodic annual increment of diameter was then correlated with and regressed on the 17 weather variables to examine effects of microclimatic conditions on the diameter growth by site types. From the correlation analysis, it was found that the diameter growth by site types was positively correlated with all of 17 weather variables except the warmth index. Especially, the conditions such as high relative humidity and large amount of sunshine hours provide favorable environment for the growth of diameter. On the other hand, it was also found that diameter growth was negatively iufluenced by warmth index. According to the regression analysis, the periodic annual increment of diameter could be well predicted by index of aridity and mean relative humidity for the growing season.

• Journal of the Korean Institute of Landscape Architecture
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• v.15 no.3
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• pp.33-50
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• 1988

This study was executed to find out how to improve on the planting and use of the plants in Kangweon- Do by surveying the planting areas -gardens, parks, streets, schools, etc. - in five cities of this province, and to select available native plants by surveying the main mountains in this province. The results are as follows ; 1. The species number within surrey areas was 319 species. and the species of which planting frequency was very high were Hibiscus syriacus, Juniperus chinensis, Buxus microphylla v. koreana, etc.. 2. The species number of school trees and flowers of 202 schools in Kangweon-Do were 33 species, 32 species respectively. and the species of school trees and flowers that showed the highest preference were Juniperus chinensis, Forsythia koreana each. 3. The species number of flowers and trees designated in 22 City and Keun were 14 species, 7 species respectively, and the species of flowers and trees that presented the highest designation frequency were Rhododendron schlippenbachii, Ginkgo biloba each. 4. The street trees planted along the main streets in Kangweon-Do were 18 species and 84,939 individuals, and the ratio of Populus alba${\times}$glandulosa was the highest among occurrence individuals. 5, As for the composition ratios of life forms of plants within survey areas, the ratio of deciduous broad-leaved tree was the highest as about 56% and that of deciduous coniferous tree was the lowest as about 1.6%. The ratios of native species versus exotic were 43 : 57 6. Through these results, it was thought that the diversification of planing species, the selection of plants suitable to each space and the generalization of use of native species were needed. So 254 plants native to Kangweon-Do were presented to correspond to these requirements.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.2
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• pp.56-72
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• 2015

This study area for this research was the Taereung of the 2009 World Heritage-listed Royal Tombs of the Joseon Dynasty. The Taereung space was divided into that of the royal tomb space, religious service space, transposition space and entry space. The original vegetation is assumed to have been planted at the right, left and backside of the tomb based on historical research literature. Regarding the original vegetation landscape of Taeneung, it was assumed that Pinus densiflora was distributed around the tomb lines and tomb space, Pinus densiflora was distributed in the religion services space and transposition and Alnus japonica was distributed in the entry space. By the present status of vegetation in Taeneung, the Pinus densiflora forest was the widest area with 50.3% with the broadleaf forest at 33.7%. Quercus aliena, Quercus acutissima, and Quercus mongolica were the main species found in Taeneung. The planting area was 7.9% and Pinus densiflora were the main species planted. To analyze the plant community structure of Taeneung, 108 plots were set and divided into four spaces. The importance of the percentage of those districts was analyzed on a spatial basis and it was found that the current dominant species of the tomb space was Pinus densiflora. However, as Pinus densiflora began dying out, the power of Quercus acutissima increased and an ecological succession from the Pinus densiflora forest to Quercus aliena forest was made. In the spaces of religious services and transposition, Pinus densiflora was decreasing and Quercus spp. was expanded. In the space of entry, the dominant species were Pinus densiflora and Quercus aliena, Pinus densiflora and Quercus aliena. As soil of this area is argillaceous, Pinus densiflora is expected to disappear in the end. The prior vegetation(assumed) and present vegetation of Taeneung were compared and analyzed and a goal of vegetation management and the way in which to manage vegetation were suggested. The goal of vegetation landscape management was to analyze ecological characteristics and vegetation changes, maintain and restore a landscape suitable for historical landscape forests by space. About the space of the tomb, Pinus densiflora forests and Pinus densiflora planting zones forests should be maintained and there should be efforts to restore and manage the Pinus densiflora forests, instead of the Quercus spp. forests. About the space of religious services, Pinus densiflora forests and Pinus densiflora planting zones should be maintained and managed and there should be efforts to restore and manage Pinus densiflora forests to replace Quercus spp. Pinus densiflora forests in the space of transposition should be maintained and managed and Pinus densiflora forests should be restored to replace Quercus spp. trees. Alnus japonica forests should be restored in the space of entry.

• Restorative Dentistry and Endodontics
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• v.34 no.5
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• pp.450-459
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• 2009

The aim of this study was to measure the initial dynamic modulus changes of light cured composites using a custom made rheometer. The custom made rheometer consisted of 3 parts: (1) a measurement unit of parallel plates made of glass rods, (2) an oscillating shear strain generator with a DC motor and a crank mechanism, (3) a stress measurement device using an electromagnetic torque sensor. This instrument could measure a maximum torque of 2Ncm, and the switch of the light-curing unit was synchronized with the rheometer. Six commercial composite resins [Z-100 (Z1), Z-250 (Z2), Z-350 (Z3), DenFil (DF), Tetric Ceram (TC), and Clearfil AP-X (CF)] were investigated. A dynamic oscillating shear test was undertaken with the rheometer. A certain volume ($14.2\;mm^3$) of composite was loaded between the parallel plates, which were made of glass rods (3 mm in diameter). An oscillating shear strain with a frequency of 6 Hz and amplitude of 0.00579 rad was applied to the specimen and the resultant stress was measured. Data acquisition started simultaneously with light curing, and the changes in visco-elasticity of composites were recorded for 10 seconds. The measurements were repeated 5 times for each composite at $25{\pm}0.5^{\circ}C$. Complex shear modulus G*, storage shear modulus G', loss shear modulus G" were calculated from the measured strain-stress curves. Time to reach the complex modulus G* of 10 MPa was determined. The G* and time to reach the G* of 10 MPa of composites were analyzed with One-way ANOVA and Tukey's test ($\alpha$ = 0.05). The results were as follows. 1. The custom made rheometer in this study reliably measured the initial visco-elastic modulus changes of composites during 10 seconds of light curing. 2. In all composites, the development of complex shear modulus G* had a latent period for $1{\sim}2$ seconds immediately after the start of light curing, and then increased rapidly during 10 seconds. 3. In all composites, the storage shear modulus G" increased steeper than the loss shear modulus G" during 10 seconds of light curing. 4. The complex shear modulus of Z1 was the highest, followed by CF, Z2, Z3, TC and DF the lowest. 5. Z1 was the fastest and DF was the slowest in the time to reach the complex shear modulus of 10 MPa.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.57-65
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• 2000

Objective of research is obtain fundamental data of carbonized wood wastes for soil condition, de-ordorization, absorption of water, carrier for microbial activity, and purifying agent for water quality of river. The carbonization technique and the properties of carbonized wood wastes(wood-based materials) were analyzed. Proximate analysis showed the wood-based materials contains 0.37~2.27% ash, 70~74% volatile matter, and 17~20% fixed carbon. As carbonization temperature was increased, the charcoal yield was decreased. However, no difference in charcoal yield was found due to time increase. The specific gravity after the carbonization decreased about 30~40% comparing to green wood. The charcoal had 1.08~4.18% ash, 5.88~13.79% volatile matter, and 80.15~90.94% fixed carbon. The pH of plywood and particleboard(pH 9 at $400^{\circ}C$, pH 10 at $600^{\circ}C$ and $800^{\circ}C$) made charcoals was higher than that of fiberboard. The water-retention capacity was not affected by the carbonization temperature and time. The water-retention capacity within 24h was about 2~2.5 times of sample weight, and the Equilibrium moisture content(EMC) became 2~10% after 24h. EMC of charcoal from the thinned trees were 9.40~11.82%($20^{\circ}C$, RH 90%), 6.87~7.61%($20^{\circ}C$, RH 65%), and 1.69~2.81%($20^{\circ}C$, RH 25%). EMC of charcoal from the wood-based materials under $20^{\circ}C$, relative humidity(RH) 90% was similar to EMC of charcoal from the thinned trees(9~11 %). However, under $20^{\circ}C$, RH 25.65%, EMC of charcoal from the wood-based materials were higher(2~3%) than EMC of charcoal from the thinned trees. Every charcoal from the wood-based materials fulfilled the criteria in JWWA K 113-1947.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.208-219
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• 1987

Newly developed several herbicides were evaluated as paddy rice herbicide at the Yeongnam Crop Experiment in 1986. And also, the general situation of rice cultivation between Korea and Japan was compared. Twenty-nine herbicides of the total 59 herbicides were used as paddy rice field in Korea while these were 100 and 187, respectively, in Japan. Among paddy rice herbicides, butachlor was the most important herbicide in both countries. However, the degree of concentration to a particular herbicide was greater in Korea compared to Japan; consumption rate of single butachlor to the total herbicide were 66.5% for Korea and 11.9%r for Japan, respectively. Pyrazolate, pyrazoxyfen and quinclorac were the most promising hebicides in pressed-type rice nurserybed in terms of herbicidal efficacy and phytotoxic effect. For transplanted paddy rice field, single application of NC-311 or combining applications of NC-311 with butachlor or quinclorac gave excellent results at the weed community that was dominated by Echinochloa crus-galli, Aneilema japonica, Ludwigia prostrata, Scirpus hotarui, Cyperus serotinus, Potamogeton distinctus and Eleocharis kuroguwai. Particularly the above combining applications maintained their excellent herbicidal effect up to 3 leaf stage of E. crus-galli without arising herbicidal phytotoxicity. Pyrazolate and three sulfonyl urea herbicides (DPX-5384, NC-311 and CGA 142464) exhibited very high safety against rice. However, Japonica type rice cultivar was a little bit more sensitive than Indica/Japonica type rice cultivar. On the other hand, the effect of these herbicides against E. crus-galli was very strong. Herbicidal effect against E. crus-galli was enhanced through shoot absorption for sulfonyl urea herbicides and root abosorption for pyrazolate and quinclorac, respectively.

• Journal of Plant Biotechnology
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• v.40 no.2
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• pp.79-87
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• 2013

The aim of this study was to establish plant regeneration from leaf explants of Sedum tosaense Makino, which is globally rare and endangered species. The leaf explants of S. tosaense were cultured on the MS medium supplemented with different concentration of BA and NAA for callus induction. Callus induction was showed the highest (100%) on MS medium containing $2.0mg{\cdot}L^{-1}$ BA and $1.0mg{\cdot}L^{-1}$ NAA. The highest number of shoots were regenerated when callus were cultured on MS medium containing $2.0mg{\cdot}L^{-1}$ BA and $1.0mg{\cdot}L^{-1}$ NAA for 5 weeks. The axillary bud were cultured on the MS media supplemented with combination of BA and NAA for in vitro propagation. The highest number of adventitious shoot (7.9 per explants) formed at $1.0mg{\cdot}L^{-1}$ NAA and $2.0mg{\cdot}L^{-1}$ BA. For rooting, MS medium supplemented with or without $2.0g{\cdot}L^{-1}$ activated charcoal was tested. The optimal results were observed using MS medium supplemented with $2.0g{\cdot}L^{-1}$ activated charcoal, on which 85.7 (No. of root), 4.6 cm (length of root). 1,200 ppm $CO_2$ and 350 ppm $CO_2$ were supplied for make certain the effects of $CO_2$ on pre-acclimatization by photoautotrophic culture. 1,200 ppm $CO_2$ treatment was established higher than 350 ppm $CO_2$ treatment. Soil acclimatization of in vitro plantlets was the best in mixture soil consisted of peat moss and perlite with 100% survival rate and they showed the maximum growth.

• Journal of Preventive Medicine and Public Health
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• v.26 no.2 s.42
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• pp.222-230
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• 1993

Industrial glues, known as 'Bonds' in Korea, contain many kinds of organic solvents, and glue sniffing of youths became one of the social problems in Korea. Mixed exposures to solvents by glue sniffing may induce chronic toxicities different from those by exposures to solvents of single component. To test effects of the glue sniffing on weight gain or central nervous system, two groups of 20 male Sprague-Dawley rats were exposed to air(control group) or vapors of the glues to narcotic status(exposed group), and weight check, tail flick test, hot plate test, rotarod treadmill test were done on the 14th,24th, 36th, 45th, 53rd, 86th, 102nd, 117th, 134th and 151st days after the first exposure. On the 188th day, their brains were excised and examined by a pathologist. Weight gain, controlled against time change, showed significant difference between the groups, but response times in tail flick test, hot plate tests, and rotarod treadmill test didn't. In pathological examination with blind method, no macroscopic or microscopic differences were found between the two groups. These results suggests that organic lesion in central nervous system may not ensue glue sniffing, but, before firm conclusion, more studies in various exposure conditions should be followed.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.403-408
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• 2010

This study was carried out to investigate the physiological responses of $Rhododendron$ $mucronulatum$ Turcz. and $R.$ $indicum$ (L.) Sweet seedlings with 0%, 35%, 55% and 75% shading of full sunlight in polyethylene film house. The shading treatments were performed during the late growth season for each species (from Sept. 9 to Nov. 5, 2008). The shading treatment was effective in reducing the daily temperature by 0.9 to $1.7^{\circ}C$ during September and by 0.8 to $1.7^{\circ}C$ during October. Before the shading treatments, the water content of $R.$ $mucronulatum$ and $R.$ $indicum$ amounted to 68.5% and 66.3%, respectively. The water contents of two species after 75% shading treatment period decreased to 66.2% (3.4% reduction) and 65.9% (0.6% reduction), respectively. Notably, both species had a similar tendency indicating less reduction rate of water content with 75% shading. $R.$ $indicum$ showed higher photosynthetic capacity with higher level of shading, and its photosynthetic capacity reached the highest level ($9.63{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). On the other hand, shading-treated $R.$ $indicum$ showed higher intercellular $CO_2$ concentration, stomatal conductance and transpiration rate (55% shading > 35% shading > 75% shading) than non-treated ones. In addition, non-treated seedlings showed higher water use efficiency than treated ones. In particular, it was found that the leaf color of $R.$ $mucronulatum$ turned equivalent to purple under full sunlight, while its leaf color kept equivalent more to green with higher level of shading, as evidenced even in naked eyes. According to comprehensive analysis using Munsell Color Chart on potential leaf color variations of $R.$ $mucronulatum$ depending on the level of shading, it was found that relatively many leaf colors under full sunlight were equivalent to R (red) and Y (yellow) chart, while relatively many leaf colors with higher level of shading were equivalent to G (green) and Y chart, where the latter still showed green color.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.3
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• pp.129-136
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• 1990

In the present report, two experiments were carried out with the purposes of knowing the differences of response among forage species to growing period and potassium level in culture solution, and investigating possible relation of the responses with occurence of grass tetany on grazing pasture. The results were as follows; (1) At 25 days after germination, fresh weight of top part as well as the sum of top and root parts of the forages increased rapidly. (2) Italian ryegrass was the highest in potassium (K) content but the lowest in magnesiurn(Mg) content among the three gramineous forages, while tall fescue showed the opposite result to it. And orchardgrass was intermediate of the two forage species (Experiment 1). (3) The K contents of forages generally increased, while Mg content became lower with the increase of K level in culture solution. The highest K contents of Italian ryegrass and orchardgrass were more than 3 times of the lowest values. The K contents of alfalfa and tall fescue increased in the narrower range. The decreases of Mg content of Italian ryegrass and orchardgrass were significant in the ranges of 5ppm to 25 or 50ppm KzO, while the content of the leguminous forages and tall fescue decreased up to 1000 level. (4) Fresh yield, water content and K content of the forages were significantly increased with the increase of K20 application levels up to 25 or 50ppm. (5) The K concentration of forage on a tissue water basis was higher at 50ppm than that at 5ppm $K_20$ level, especially for Italian ryegrass and orchardgrass with the value of 2.6times and 2.5times, respectively. However, the K concentration (tissue water) of leguminous forages increased gradually up to the level of lOOOppm (Experiment 2). It is suggested from the results that rapid changes of water content, Mg content and K concentration (tissue water) may occur to forage on a grazing pasture, when both growing period and K level in the soil affect the changes simultaneously. Under such conditions, plant water especially in Italian reyegrass and orchardgrass can function as toxic material to grazing ruminants.