• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.261-267
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• 2006

A nursery trial comprising 109 progenies of 5 populations of Cornus kousa was analysed using multivariate analysis of 12 quantitative traits (growth and leaf form). The aim of this study was to examine geographic variation of the species based on the single, existing nursery trial to support a genetic resource conservation plan of Cornus kousa in Korea. Nested Anova showed that there were statistically significant differences among populations as well as among families within populations in all 12 quantitative traits. In 10 of 12 traits, variance components among families within populations were higher than those among populations. Cluster analysis using complete linkage method showed three groups to Euclidean distance 0.8. Among principal components, primary 2 principal components appeared to be major variables because of the loading contribution of 91.9%. The first contribution component was maximum width, vein number, blade length/petiole length and upper 1/3 width lower 1/3 width; the second one was height, diameter at root collar, blade length, upper 1/3 width, petiole length and petiole length/vein number, respectively. But all characters showed no significant difference with the pattern of geographic distribution.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.323-327
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• 2006

This study was conducted to understand response of damage and tolerance to ozone between ozone tolerant and sensitive families of P. densiflora which had been selected by the based on visual injury and growth. Five individuals were selected in each group, and were exposed to 100ppb ozone for 90 days. Every 30 days after ozone fumigation, diamter at root collar (ORC), superoxide dismutase (SOD) activity, and malondialdehyde (MDA) content were measured. In early state of ozone fumigation tolerant families showed three times higher relative DRC growth rate than sensitive families. And during whole fumigation period growth rate of tolerant families was superior to growth rate of sensitive families. SOD activity in sensitive families was increased 30 days after fumigation, and in accordance with fumigation period extended it was decreased continuously. MDA content in ozone treatment showed higher than in control, and MDA content of tolerant families was higher than that sensitive families. In our results tolerant families has higher antioxidative activity than sensitive families. Therefore tolerant families can restrain lipid peroxidation and damage on physiological activity.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.250-255
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• 2006

Pinus densiflora is a dominant conifer species in Korea and also distributed in regions of Japan and eastern China. Success in the establishment and productivity of forest tree plantation is largely determined by selection of species and seed source. The provenance tests of Pinus densiflora in Korea are underway. However, the information of the growth performance of Japanese and Chinese provenances are insufficient. Therefore, this study was conducted to evaluate the growth performance of Pinus densiflora Japanese provenances. Data were collected from a provenance trial including established by Korea Forest Research Institude at Chungju in 1970. Six Japanese provenances ($31^{\circ}90^{\prime}{\sim}40^{\circ} 27^{\prime}$ in latitude and $128^{\circ}47^{\prime}{\sim}141^{\circ}80^{\prime}$ in longitude) were included in this trial. Pyeongchang provenance at Kangwon province in Korea was used for reference provenance. At nursery stage, the height and diameter at root collar of six Japanese provenances were smaller than those of Pyeongchang provenance. Among Japanese provenances, Kasahara provenance showed higher growth performance than those of others. The provenance rankings of growth performance were fluctuated until age 11. However, the growth performance of Japanese provenances showed higher than those of reference provenance after age 17. Kirishima-yama provenance showed best growth performance. Simple correlation analysis was conducted to investigate the geographic factors affecting growth performance. The height growth showed negative corelation with latitude of seed origin. Generally, Japanese provenences of Pinus densiflora were well adapted and grown in Chungju. However, it was suggested that further studies on other sites need to generalize the results of this study.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.316-322
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• 2006

This study was conducted to examine the changes of seed characteristics and germination properties and to determine the most suitable collection time in Ulmus davidiana var. japonica. Seeds were collected six times with the interval of seven days after April 21, 2005 at Jeong-seon. There were differences in seed characteristics and germination properties among seed collection times. The sizes of seed and fruit increased with the collection time, but seed moisture contents decreased with the collection time after increasing until May 5. The 1,000 seeds weight decreased with the collection time after increasing until May 12. Collection time showed high positive correlations (r=0.790, p<0.01) with seed size and negative correlations (r=-0.919, p<0.01) with moisture contents. Percent germination (PG) presented the highest value in seeds collected at May 5, and decreased with the collection time. Mean germination time(MGT), germination speed(GS), and germination performance index(GPI) also showed the highest values in seeds collected at May 5. PG, MGT, and GS had correlations with other seed characteristics except the 1,000 seed weight. The relative growth rate of height and root collar diameter of seedlings presented the highest values in seedling germinated from seed collected at May 5, and seedlings germinated from seeds collected at May 5 and 12 showed the highest values in chlorophyll contents. Consequently it will be possible to product a number of seedlings when the seeds of U. davidiana var. japonica are collected just before drying morphologically.

• Journal of the Korean association of regional geographers
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• v.8 no.4
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• pp.430-450
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• 2002

This study empirically analyses the spatial features of land use and transportation, and residential characteristics of the cases of the Sangin and Siji newly developed districts in Taegu. Before the development, the areas consisted mainly of rice paddies and fields; these areas are now filled with high-density residential complexes, with a proliferation of commerce and service functions. In Sangin, restaurants, retail services, bars and bakeries are the main developments, but Siji developed retail services, restaurants, private institutions for students, and facilities for convenience goods. While the public transportation system is oriented to CBD, the inter-districts transportation network is lacking. The residents are mainly in their 40s to 50s, with white collar jobs. They have a relatively high level of education with high income. They have migrated a relatively short distance to the district. The locational(pull) factors influencing the decision to migrate, for Sangin are transportation, the physical environment and access to the working place, but for Siji it has been the physical environment, the school group, and access to the working place. The main dissatisfaction factors for Sangin are the management fee, the school group and for Siji they are commuting, the management fee and transportation.

• Korean Journal of Community Nutrition
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• v.21 no.3
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• pp.237-246
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• 2016

Objectives: To investigate the effect of a worksite-based dietary intervention program for the management of metabolic syndrome (MS) among male employees. Methods: A dietary intervention program combining individual and environmental approach was implemented targeting white-collar employees at a worksite located in Seoul for 10 weeks. Out of 104 employees having agreed to participate in the program, those having three or more out of five components of MS and having two components, including a waist circumference component were classified into "the high risk group" (n=41) and received group nutrition education and individual nutrition counseling three times each. The rest of the study subjects were considered as "the low risk group" (n=63). The food environment at the worksite, where both the high and low risk groups were exposed, was changed to promote healthy eating. Physical data including MS components were collected and a questionnaire on dietary behaviors was administered before and after the intervention. The data from the high risk group (n=17) and the low risk group (n=20), excluding the subjects ineligible for or failed to complete the study (n=67), were analyzed. The difference before and after intervention was tested for significance by Wilcoxon signed-rank tests. Results: Weight, body mass index (BMI), waist circumference, blood pressure, HDL-cholesterol, and HbA1c and the healthy dietary practice score improved significantly after intervention in the high risk group. The median number of MS components decreased significantly from 3.0 to 1.0 in the high risk group. In the low risk group, only HbA1c significantly decreased. Conclusions: The 10-week worksite-based dietary intervention program combining individual and environmental approach was found to be effective for managing MS of male employees.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.6
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• pp.664-670
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• 2004

Statement of problem. One of the common problems of dental implant prosthesis is the loosening of the screw that connects each component, and this problem is more common in single implant-supported prostheses with external connection. Purpose. The purpose of this study was to examine the changes of detorque values of abutment screws with external connection in different abutment heights. Materials and methods. After cyclic loading on three different abutment heights, detorque values were measured. Abutments were retained with titanium abutment screws tightened to 30 Ncm (30.5 kgmm) with digital torque gauge as recommended by the manufacturer. Replacing abutments, implants and titanium abutment screws with new ones at every measurement, initial detorque values were measured six times. In measuring de torque values after cyclic loading, Avana Cemented Abutments of 4.0 mm collar, 7.0 mm height (Osstem Co., Ltd., Seoul, Korea) were used with three different lengths of 5.0, 8.0, 11.0 mm. Shorter abutments were made by milling of 11.0 mm abutment to have the same force-exercised area of 4.5 mm diameter. Sine curve force (20N-320N, 14Hz) was applied, and detorque values were measured after cyclic loading of 2 million times by loading machine. Detorque values of initial and after-loading were measured by digital torque gauge. One-way ANOVA was employed to see if there was any influence from different abutment heights. Results. The results were as follows: 1. The initial detorque value was 27.8$\pm$0.93 kgmm, and the ratio of the initial detorque value to the tightening torque was 0.91(27.8/30.5). 2. Measured detorque values after cyclic loading were declined as the height of the abutment increased, that was, 5.0 mm; 22.3$\pm$0.82 kgmm, 8.0 mm; 21.8$\pm$0.93 kgmm, and 11.0 mm; 21.3$\pm$0.94 kgmm. 3. One-way ANOVA showed no statistically significant differences among these (p>0.05). 4. Noticeable mobility at the implant-abutment interface was not observed in any case after cyclic loading at all.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.1
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• pp.45-53
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• 2000

To analyze the photodegradation mechanism of materials for fisheries facilities which stand for considerable time immediately under or even partly above the water surface, such as cage collar, cage net, stationary fishing gear, egc. after 900 hours exposure, weathering experiments on 3 kinds of netting twines like dyed polyethylene(PE) and nylon, and non-treated high strength PE(Hi-PE) were carried out by using xenon light source. The results obtained are as follows : It was observed by scanning electron micrograph(SEM) that a good protection by pigments was obtained in PE and nylon specimen, while crack was rapidly progressed at the surface of Hi-PE one owing to etching by UVR. There was a little increase in density resulting from reorientation of polymer chain, chain scission, etc. in Hi-PE specimen. A wide angle X-ray diffraction showed that 3 kinds of specimens had no fundamental changes in polymer crystalline structure considering each 2$\theta$ of diffraction peak. Remaining tenacity of netting twines was in order of PE, nylon, and Hi-PE after having been exposed to the effect of 900 hours. PE and nylon treated with stuffs were shown to be more resilient than non-treated Hi-PE as confirmed by SEM.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.4
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• pp.210-218
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• 2013

The sea breeze shows different characteristics compared to land breeze, such as high wind speed and more rapider shift period. One of the major factors affecting plant early growth is wind speed. In the early growth stage, tree growth-rates rise with decreasing wind speed. Thus, the study was performed to identify wind break effects on wind characteristics and tree growth. The wind break used in this study was about 130 meters length and 3 meters height, made up with poly-ethylene (with 40% openness). We installed one vane and fifteen anemographs at three different heights (1, 2 and 3 meters) on the inner and outer wind break areas. The wind characteristic and plant growth data were collected from Jun. 2011 to Oct. over 2012. The wind rose of the Saemangum seawall area presented the north (21.5%) and it was followed by north-west (18.1%), east (14.9%) and north-east (13.7%) and the remainder with other directions. Wind speeds at height were different. The tree height was 159.6 cm at inside and 129.6 cm at outside. The diameter at root-collar was 36.9 mm at inside and 32.6 mm at outside from wind break.

• Journal of Conservation Science
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• v.33 no.5
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• pp.363-370
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• 2017

The aim of this study was to obtain information about two early-20th Century clothes, for which the "National Memorial Museum of Forced Mobilization under Japanese Occupation" has sought to receive preservation treatment. Optical microscopes and a scanning electron microscope were used to investigate the weaving of the clothes, and Fourier transform infrared spectroscopy(FT-IR) was used to investigate the fibers. Cloth A is believed to be a Japanese half sleeved inner wear(Hanjuban) used by women. Cloth B is believed to be working clothing that was checked by an Osaka plant. This was verified by a book written by the Japanese army. Both of the clothes were made mostly from cotton, although the inner wear also used viscose rayon on the neck collar. The button on the working wear was made of urea formaldehyde resin, an early precursor to plastic.