• Journal of Korean Society of Forest Science
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• v.46 no.1
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• pp.10-20
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• 1980

This experiment was carried out to investigate the effects of physico-chemical properties of soil on the growth of Chamaecyparis obtusa and to apply the results to such rational forest management as yield forecast and selection of suitable species for a given forest stand. The soil properties observed in this experiment were soil pH, exchangeable pH organic matter, total nitrogen, available $P_2O_5$, cation exchange capacity, exchangeable $H^+$, total base and base saturation. Diameter at breast height (DBH), height and volume growth of C. obtusa were observed at 78 sampling sites. Data were processed into the following series for the analysis of multivariates : inner correlation matrix, multiple correlation coefficients, regression coefficients and partial correlation coefficients. The results are summerized as follows : 1. Multiple correlation coefficients between soil properties and DBH of C. obtusa were .364 for 20-year trees, resulting less efficient for estimating the growth of C. obtusa. However, total base, soil pH and base saturation were considerable characters for better estimation. 2. More efficient multiple correlation coefficients were observed between soil properties and height growth than those between soil properties and DBH, showing .443 for 20-year trees and factors affecting the height growth were similar to those of DBH. 3. Extremely low values of multiple correlation coefficients were estimated between physico-chemical properties of soil and volume growth of C. obtusa resulting low efficient estimation. However, total base contributed highly to volume growth of C. obtusa. Accordingly the most contributable factor for estimating the growth of C. obtusa were total base, soil pH and base saturation. Consequently, these results can be effective for selecting of the reforesting site, and less effective for estimating the growth of C. obtusa.

• Journal of Korean Society of Forest Science
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• v.14 no.1
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• pp.33-38
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• 1972

This study was carried out to investigate on the variation of wood fiber dimensions of some oakwoods. Every 2 annual ring was selected for specimens from pith toward bark up to 28th annual ring on 3 species of Oak SINGALNAMOO(Quercus mongorica Fisch.), JOLCHAMNAMOO(Quercus serrata Thunb.) and KULCHAMNAMOO(Quercus variabilis Blume) which grew in Mt. Jiri. The investgated results are as follows: 1. Values of wood fiber lengths increase rapidly up to 16th annual ring, however, considerably stable at the rear part. Range of wood fiber length variations: Species Range of length(mean) CV SINGALNAMOO, $640{\sim}1,544{\mu}$($1,142.3{\mu}$), 8~16% JOLCHAMNAMOO, $592{\sim}1,600{\mu}$($1,179.6{\mu}$), 6~21% KULCHAMNAMOO, $679{\sim}1,592{\mu}$($1,298.9{\mu}$), 2~15% 2. The increment of wood fiber width and thickness by annual rings shows quite inactive contrary to the length. Range of wood fiber width: $7.6{\sim}10.0{\mu}$(mean $9.3{\mu}$) Range of wood fiber thickness: $2.0{\sim}3.2{\mu}$(mean $2.6{\mu}$) 3. There was no significance between species through their wood fiber lengths. 4. And these wood fibers believed to be valuable for pulp-wood through their fiber bonding ratio, Runkel ratio and flexibility coefficient.

• Journal of Korean Society of Forest Science
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• v.86 no.2
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• pp.241-250
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• 1997

The study was conducted to make a map for selecting righteous tree species for each site by digital terrain analysis. We set an algorithmic value for each tree species' characteristics with distribution pattern analysis, and the soil types were digitized from data indicated on soil map. Mean altitude, slope, aspect and micro-topography were estimated from the digital map for each block which had been calculated by regression equations with altitude. The results obtained from the study could be summarized as follows 1. We could develope a method to select righteous tree species for a given site with concern of soil, forest condition and topographic factors on Muju-Gun in Chonbuk province(2,500ha) by the terrain analysis and multi-variate digital map with a personal computer. 2. The brown forest soils were major soil types for the study area, and 29 tree species were occurred with Pinus densiflora as a dominant species. The differences in site condition and soil properties resulted in site quality differences for each tree species. 3. We tried to figure out the accuracy of a basic program(DTM.BAS) enterprised for this study with comparing the mean altitude and aspect calculated from the topographic terrain analysis map and those from surveyed data. The differences between the values were less than 5% which could be accepted as a statistically allowable value for altitude, as well as the values for aspect showed no differences between both the mean altitude and aspect. The result may indicate that the program can be used further in efficiency. 4. From the righteous-site selection map, the 2nd group(R, $B_1$) took the largest area with 46% followed by non-forest area (L) with 23%, the 5th group with 7% and the 4th group with 5%, respectively. The other groups occupied less than 6%. 5. We suggested four types of management tools by silvicultural tree species with considering soil type and topographic conditions.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.403-408
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• 2015

Color is one of the quality determining factors for pepper powder. To measure the color of pepper powder, several methods including high-performance liquid chromatography (HPLC), thin layer chromatography (TLC), and ASTA-20 have been used. Among the methods, the ASTA-20 method is most widely used for color measurement of a large number of samples because of its simplicity and accuracy. However it requires time consuming preprocessing steps and generates chemical waste containing acetone. As an alternative, we developed a fast and simple method based on a visible/near infrared (Vis/NIR) hyperspectral method to measure the color of pepper powder. To evaluate correlation between the ASTA-20 and the visible/near infrared (Vis/NIR) hyperspectral methods, we first measured the color of a total of 488 pepper powder samples using the two methods. Then, a partial least squares (PLS) model was postulated using the color values of randomly selected 3 66 samples to predict ASTA values of unknown samples. When the ASTA values predicted by the PLS model were compared with those of the ASTA-20 method for 122 samples not used for model development, there was very high correlation between two methods ($R^2=0.88$) demonstrating reliability of Vis/NIR hyperspectral method. We believe that this simple and fast method is suitable for highthroughput screening of a large number of samples because this method does not require preprocessing steps required for the ASTA-20 method, and takes less than 30 min to measure the color of pepper powder.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.435-442
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• 2015

The main objective of this work was to identify and evaluate possible substrate alternatives or amendments to peat moss. This study involves the physical and chemical characterization and growth test of wood sawdust and wood fiber in order to evaluate their use as components of horticultural media. The carbohydrate content, C/N ratio, pH, phenolic compound, total porosity and water holding capacity were 58.9%, 425.1, 4.8, 181.8 ($mg{\cdot}g^{-1}$), 82.5% and 47.1% in wood sawdust and 41.1%, 240.8, 5.9, 29.8 ($mg{\cdot}g^{-1}$), 90.6% and 56.2% in wood fiber, respectively. Wood sawdust (K, $998.0mg{\cdot}100g^{-1}$ ; Ca, $1196.0mg{\cdot}100g^{-1}$; Mg, $105.6mg{\cdot}100g^{-1}$) and wood fiber (K, $1250.1mg{\cdot}100g^{-1}$; Ca, $1982.6mg{\cdot}100g^{-1}$; Mg, $173.1mg{\cdot}100g^{-1}$) showed adequate mineral elements properties compared to peat moss (K, $0.02mg{\cdot}100g^{-1}$; Ca, $0.57mg{\cdot}100g^{-1}$; Mg, $0.13mg{\cdot}100g^{-1}$) for their use as growing media. The mixtures of the horticultural media were prepared using different substrate as wood sawdust and wood fiber to grow Chinese cabbage (Brassica campestris L.) in a greenhouse. The seed germination, leaf area and stem height were 75%, $0.50cm^2$ and 2.8 cm in PS substrate (containing 30% peat moss, 10% perlite and 60% wood sawdust) and 95%, $0.65cm^2$ and 3.3 cm in PF substrate (containing 30% peat moss, 10% perlite and 60% wood fiber), respectively. The seed germination and stem height of the PF substrate (containing 30% peat moss, 10% perlite and 60% wood fiber) was higher than those in peat moss (control). Utilization of wood by-product can be considered as an alternative media component to substitute the widely using expensive peat moss.

• Journal of the Korean earth science society
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• v.36 no.2
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• pp.139-157
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• 2015

We investigated the relative errors of satellite-observed Surface Skin Temperature (SST) data caused by sea ice in the northern hemispheric ocean ($30-90^{\circ}N$) during April 16-24, 2003-2014 by intercomparing MODerate Resolution Imaging Spectroradiometer (MODIS) Ice Surface Temperature (IST) data with two types of Atmospheric Infrared Sounder (AIRS) SST data including one with the AIRS/Advanced Microwave Sounding Unit-A (AMSU) and the other with 'AIRS only'. The MODIS temperatures, compared to the AIRS/AMSU, were systematically up to ~1.6 K high near the sea ice boundaries but up to ~2 K low in the sea ice regions. The main reason of the difference of skin temperatures is that the MODIS algorithm used infrared channels for the sea ice detection (i.e., surface classification), while microwave channels were additionally utilized in the AIRS/AMSU. The 'AIRS only' algorithm has been developed from NASA's Goddard Space Flight Center (NASA/GSFC) to prepare for the degradation of AMSU-A by revising part of the AIRS/AMSU algorithm. The SST of 'AIRS only' compared to AIRS/AMSU showed a bias of 0.13 K with RMSE of 0.55 K over the $30-90^{\circ}N$ region. The difference between AIRS/AMSU and 'AIRS only' was larger over the sea ice boundary than in other regions because the 'AIRS only' algorithm utilized the GCM temperature product (NOAA Global Forecast System) over seasonally-varying frozen oceans instead of the AMSU microwave data. Three kinds of the skin temperatures consistently showed significant warming trends ($0.23-0.28Kyr^{-1}$) in the latitude band of $70-80^{\circ}N$. The systematic disagreement among the skin temperatures could affect the discrepancies of their trends in the same direction of either warming or cooling.

• Journal of the Korean earth science society
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• v.36 no.2
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• pp.171-180
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• 2015

Regarding the tropical cyclone (TC) genesis frequency, TCs between 1999 and 2013 were generated more frequently in the northwest waters of the tropical- and subtropical western North Pacific than TCs between 1977 and 1998. TCs over the period from 1977-1998 showed a northward track trend generated mostly from the distant sea in east of the Philippines via the mainland of the Philippines and the South China Sea to the west toward Indochina or from the distant sea in east of the Philippines to the distance sea in east of Japan. TCS over the period from 1999-2013 showed a northward shift pattern to the mid-latitude region mostly in East Asia. Therefore, TCs over the period from 1999-2013 tended to move to much higher latitudes than TCs over the period from 1977-1998, which also resulted in the high possibility of maximum TC intensity occurred in higher latitudes during the former period than the latter period. In the difference of 500 hPa streamline between two periods, the anomalous anticyclonic circulations were strengthened in $30-50^{\circ}N$ whereas the anomalous monsoon trough was placed in north of the South China Sea, which was extended to the east up to $145^{\circ}E$. The mid-latitude in East Asia is affected by the anomalous southeasterlies due to the above anomalous anticyclonic circulations and anomalous monsoon trough. The anomalous southeasterlies play a role in anomalous steering flows that directed TCs to the mid-latitude regions in East Asia, which made the latitudes of the maximum intensities in TCs over the period from 1999 - 2013 further to the north than those in TCs over the period from 1977-1998.

• Journal of dental hygiene science
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• v.11 no.2
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• pp.69-76
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• 2011

The aim of this study was to compare the effects on the resistance to demineralization by the frequency and method of fluoride application in vitro. ninety-one human enamel specimens were embedded in acrylic resin with the labial surfaces exposes. The specimens were divided into 7 groups; (1) non-treated; (2) 1.23% APF gel 1 time; (3) 2% NaF sol 1 time; (4) 2% NaF sol iontophoresis 1 time; (5) 1.23% APF gel 4 time; (6) 2% NaF sol 4 time; (7) 2% NaF sol iontophoresis 4 time. All the groups were immersed in the remineralizing solution (RS) before baseline and divided into 7 test groups of 13 specimens each. All the specimens were exposed to a pH-cycling model which consisted of demineralization (6 hours) and remineralization (18 hours) for 5 days. The Vickers surface micro-hardness number of all the specimens was measured using microhardness tester and the specimen surfaces were observed by scanning electron microscope (SEM). The results were analyzed using one-way ANOVA followed a Tukey's multiple comparison at a significance level of 0.05. The group 7 showed higher level of microhardness after Fluoride application. The group 1 showed lowest level of microhardness but group 7 showed higher level of microhardness after pH-cycling model, there were significant differences between groups. After the modified pH-cycling, the 2% NaF solution with the iontophoresis group showed the best resistance to demineralization(p<0.05). These results were also confirmed by SEM. The fluoride iontophoresis method was the most effective of the regimens in increasing the acid resistance of the enamel.

• Journal of dental hygiene science
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• v.11 no.2
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• pp.91-97
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• 2011

The aim of this study was to investigate the prevention effect of oral disease on the school-based toothbrushing program(SBTBP) in Daejeon in 30 months. The experimental subjects were the 5th grade's 70 students who have gone to school with the school-based toothbrushing program since the 3th-grade. The control school was located in close geographical area with similar economical status. The questionnaire about oral health knowledge and behavior was done by self-recording. After one dentist examined the dental caries and periodontal status, the gingival crevicular fluid(GCF) was collected with #25 paperpoint for 1 miniutes. Matrix Metalloproteinase(MMP)-9 in GCF was analyzed by ELISA. The SBTBP group had the upper oral health knowledge than the control significantly(p<0.001), but, the SBTBP group had no difference of the oral health behavior from the control. Although the SBTBP group had the lower plaque index than the control significantly(p=0.02), the SBTBP group had no difference of the gingival index, calculus index and the concentration of MMP-9 in GCF from the control. In conclusion, The SBTBP had the effect to reduce the dental plaque and to improve the oral health knowledge. On the other hand, the effect to prevent dental caries and periodontal disease of SBTBP was not clear.

• Journal of dental hygiene science
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• v.11 no.2
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• pp.107-119
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• 2011

The purpose of this study was to examine the effects of oral health behavior by oral health belief from the students in the dental hygienics department who take charge of oral health office, and therefore to lead a clear oral health care, to complete desirable oral health belief, and finally to utilize them for oral health field. The survey was conducted using structured self-administered questionnaires based on oral health belief model targeting 163 students in the dental hygienics department of one of the college in Seoul, and collected data were statistically analyzed using the SPSS 18.0 program. As a result of analysis to determine that the oral health belief significantly affects on the oral heal behavior, the personal variables such as age, economic status and occupation, and the seriousness for the oral health belief were indicated to be significant variables(p<0.05), and as a result of analysis that effects on the number of the oral health behavior, the susceptibility and the seriousness were indicated to be significant variables for oral health belief(P<0.05). As a conclusion, oral health belief was identified as a factor of salience through understanding that oral health belief of the students in the dental hygienics department effects on oral health behavior based on an oral health belief model, and it can be concluded that the necessity of oral health belief investigation should be discussed as a crucial issue to provide a more effective oral health promotion plan.