• The Korean Journal of Ecology
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• v.16 no.3
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• pp.239-259
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• 1993

The vegetation types and distributional characteristics of the forest vegetation on Mt. Ilwol were investigated by the Z-M school method. Geographical distribution of the vegetation was a central/montane(CEMO) type of the Korean Peninsula subtype. The forest was classified into five vegetation units: Artemisio-Quercetum mongolicae (Artemisio-Quercetum typicum subass. nov., Artemsio-Quercetum pinetosum dens~florae subass. nov. ). Lychno-Quercetum mongolicae (Lychno-Quercetum Calamagrostetosum arundinaceae subass. nov.. Lychno-Quercetum ligularetosum f~scherii subass. nov.), Fraxinus rhynchophylla community, Quercus variabilis community and Larix leptolepis afforestation. Species with percentage constance degree more than 61% are Quercus mongolica (89.5%, V), Lespedeza maximowiczii (73.7%, IV), Isodon japonicus(73.7%, IV), Fraxinus rhynchophylla (68.%, IV), Arlemisia stolonifera (65, 8%, IV), etc. Artemisio-Quercetum mongolicae was chiefly distributed on the ridge lines of low altitudes (570~700m) and on the ground with exposed rocks in sloping surface (800~1, 000m). Both Fraxinus sievoldiana and Rhododendrou schlippenbachii of the Artemisio-Quercetum mongolicae showed a predominant condition all over the subtree and shrub layers. Of Artemisio-Quercetum pinetosum densifloraes, Pinus densiflora becomes powerful over the tree layer and, on the other hand, Quercus mongolica over the subtree layer. Lychno-Quercetum mongolicae was distributed somewhat on the humid region of the high altitude area (840~1.200m). Fraxinus rhynchophylla community was chiefly distributed in the vicinity of the ravines. Quereus rariabilis community was distributed at subxeric slope on southeast side of the mountain. Larix leptolepis has been reforested at the ecotone between Artemisio-Quercetum mongolicae and Lychno-Quercetum mongolicae. Percentage cover degrees of the subtree layer In Lychno-Quercetum mongolicae, Quereus rariabilis community and Larix leptolepis afforestation were relatively low, 15.3%, 5% and 2.5%, respectively.The contents of moisutre and organic matter in the soil were much higher in Luchno-Quercetum monogolicae and Larix leptolepis afforestaion than in the other communities. Contents o Ca, Mg, K and the available phosphorus were relaively high compared with forests of the other area. This result seems to be influenced by a forest fire. As the altitude increases, the moisure content in the forest soil also increases.

• Korean Journal of Remote Sensing
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• v.36 no.2_1
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• pp.179-197
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• 2020

Topographic normalization reduces the terrain effects on reflectance by adjusting the brightness values of the image pixels to be equal if the pixels cover the same land-cover. Topographic effects are induced by the imaging conditions and tend to be large in high mountainousregions. Therefore, image analysis on mountainous terrain such as estimation of wildfire damage assessment requires appropriate topographic normalization techniques to yield accurate image processing results. However, most of the previous studies focused on the evaluation of topographic normalization on satellite images with moderate-low spatial resolution. Thus, the alleviation of topographic effects on multi-temporal high-resolution images was not dealt enough. In this study, the evaluation of terrain normalization was performed for each band to select the optimal technical combinations for rapid and accurate wildfire damage assessment using PlanetScope images. PlanetScope has considerable potential in the disaster management field as it satisfies the rapid image acquisition by providing the 3 m resolution daily image with global coverage. For comparison of topographic normalization techniques, seven widely used methods were employed on both pre-fire and post-fire images. The analysis on bi-temporal images suggests the optimal combination of techniques which can be applied on images with different land-cover composition. Then, the vegetation index was calculated from the images after the topographic normalization with the proposed method. The wildfire damage detection results were obtained by thresholding the index and showed improvementsin detection accuracy for both object-based and pixel-based image analysis. In addition, the burn severity map was constructed to verify the effects oftopographic correction on a continuous distribution of brightness values.

• Journal of Korean Society of Transportation
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• v.30 no.3
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• pp.95-106
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• 2012

The railway service in the Seoul metropolitan area is facing variety of l changes such as extension of service coverage, new construction, and introduction of express service which in turn causes changes on demands. The demand affects train operation characteristics (frequency of service, train formation) as well as on the congestion rate which is one of the major evaluation index in metropolitan area user service. For the efficient operation of the train, the relationship among the minimization of fleet number, operating cost, and service level has been analyzed. Using the Powersim, which is a system dynamics (System Dynamics) simulation program for realizing optimized simulation for train-formation, this paper identified that some stations of Gyeong-bu line exceeded limit congestion rate(150%) of a fleet already that means it is best to maintain current condition of the line; however, the Gyeong-in line and the Gwa-chon line showed no excess of the limit congestion rate so that it is possible to reduce 2-4 fleets of train for efficient operation. In addition, in case of Jang-hang line between Cheon-an and Sin-chang, a train consisting of 10 fleets provides services which is same formation of train for Gyeong-bu line. This study proved that the congestion rate will not rise greatly with only 4 fleets of a train for the service in Jang-hang line, and it is considered that a study for shuttle service between Cheon-an and Sin-chang is necessary.

• Korean Journal of Ecology and Environment
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• v.53 no.2
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• pp.208-219
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• 2020

Forest thinning brought the large variation to forest ecosystem including environment and animal. Our study was result of long-term monitoring for ground-dwelling arthropod communities after thinning in forest ecosystem. In this study, we conducted field study on plantation forest in Chuncheon, Korea in 2018, and compared with previous study data (2006 and 2008). We found that the effect of thinning was still existent 10 years later from thinning with difference of habitat environment(depth of ground organic matter, coverage rate of ground vegetation and canopy). And ground-dwelling arthropod communities showed changes of abundance and taxa at the study area and thinning conditions. Ground-dwelling arthropod communities in 2018 were dominant in the order of Diptera, Hymenoptera, Coleoptera (Insecta), Araneae (Arachnida) and Collembola (Collembola). Among the conditions of thinning, Araneae (Arachnida), Coleoptera and Hymenoptera (Insecta) showed amount of abundance in heavy thinning. And Collembola (Collembola) and Diptera (Insecta) were most common in area of light thinning. In 2018 ground-dwelling arthropod communities, abundance of Diptera and Coleoptera (Insecta) and Isopoda (Crustacea) were decreased although Hemiptera and Orthoptera (Insecta) were increased than 2008 arthropod communities. Arthropod communities in 2018 were more similar with those in 2008 (after thinning) than with those in 2006 (before thinning).

• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1119-1122
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• 2006

Aeration by using diffusers usually requires approximately 50~90% of the total electricity needed to operate WWTP (WasteWater Treatment Plant)s. Accurate evaluation of the oxygen transfer efficiency for an aeration system, and recommendation of a better alternative may help saving WWTP operational costs. Appropriate techniques and methods to achieve this purpose have not been introduced in Korea. In this study, in-process analysis was performed for a coarse bubble aeration system by the off-gas method to evaluate its applicability in Korea. To accomplish this analysis, an off-gas test, unsteady-state clean water test and steady-state off-gas column test was conducted and comparisons to other aeration systems were made. The ${\alpha}$ and the F estimated from the results of the unsteady-state clean water test and the steady-state off-gas column test were 0.61 and 0.90 respectively in a coarse bubble aeration system. The comparison of P.E tube diffusers laid out single spiral roll and ceramic dome diffusers laid out full floor coverage showed that the oxygen transfer efficiency of the coarse bubble aeration system was less than or similar to other aeration systems. But, airflow rates per unit area were 4~5 times greater than other aeration systems. In regards to the oxygen transfer efficiency for airflow rates per unit area, a retrofit to higher efficiency diffusers was urgently needed. This study showed proved that off-gas methods can apply to evaluate diffuser performances to estimate operating factors and to compare other aeration systems in Korea.

• Korean Journal of Adult Nursing
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• v.12 no.2
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• pp.296-310
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• 2000

During the past 10 years, concern for community people's health has increased together with the changes. Public health policies and studies for community people's health, however, have influenced those in childmaternal health care to want more general coverage and studies of health and wellness. Particularly, the study of community people's health in the extent an island area is almost rare as that personal and the material benefits in this area are lacking of community people's work is large, and the basic elements of living, such as diet and elimination, are irregular due to the schedule of the tide. Thus, there are many potential health problems. In this regard, the study attempted to understand the health problems of island community people and to provide a basis for developing health promotion and health education programs. In collecting data for the study, face to face interviews were made through a structured questionnaire from October 1 to December 30, 1996. Collected data were analyzed with the SAS statistics program, descriptive statistics, t-test and ANOVA. Subjects' health status was examined by classifying into such categories as their health perception, complaints of health problem, related lifestyle, psychosocial health staus, the result of examination is as follows; 1. For subjects' health perception, 26.9% of the subject answered not sick, but not so healthy'; 30.9% thought they were healthy, while 22.9% answered that they were not healthy. 2. For the health problem complaints many complained of pains in their muscles and skeletal system, especially knee joint pain. Women's health problems related with breast and the reproductive system included 52.3% of cases doing breast self examination, while 56.55% received the cervical cancer screening test. In men's health problems, 44.2% of subjects answered that they have moderate to severe BPH(Benign Prostatic Hypertrophy) symptom. 3. There were statistically a significant difference in the degree of physical health according to marital status(p=0.0028), occupation(p=0.0442), income(p=0.0357). 4. For stress status, 17.2% was to need the intervention, 50.2% was to need observation. 5. The mean score of self-esteem was 27.7 showing a relatively high score. 6. For the rate of smoking, 37.7% used to smoke, while 28% used to take alcohol. 7. The rate of substance abuse was 45.9% of subjects. 8. Most of subjects' health behaviors included most of the acupuncture (52%). 9. The rate of subjects receiving comprehensive medical testing was 34.36% while 34.78% did after care managing behavior. 10. For the obesity grade, 53% is normal weight, low-weight 32.8%, obesity 33%. 11. For nutrition status, 78.7% illy balanced to need intervention of nutritional education. 12. For 78.7% of subjects, muscle strength and 40.7% of stretching were not good enough to need health education on physical exercises. Therefore, based on the results, appropriate health education programs need to be developed to promote health of community people on an island.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.157-168
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• 1999

This paper analyzed vegetation and land use classification, slope and permanent preservation and legal reserves on the farm Jangada and Jamaica-Mato Grosso do Sul, Brazil, using satellite image for assisting the planning of planting Eucalyptus spp. This part of the State of Mato Grosso do Sul represents an important geopolitcal area, since it is located on the borders of Bolivia and Paraguay. Also exportation of goods can be achieved through hydrovias extending to Buenos Aires, Argentina-through the Paraguay River. Also there are road and railroad connection which link the soutreastern part of Brazil to the Andean countries. The vegetation map from sheet SF 21-Campo Grande of the RADAMBRASIL Project was used as the basis for the preliminary interpretation of coverage, and complemented by a visit of the field. After the initial interpretation of the image, definition of classes of use and land occupation were made, and files of spectral signatures were created. On the farms Jamaica and Jangada Open Arboreal Savanna and Grass Savanna are the predominant physiognomies occupying 68% of total area. In spite of the results being satisfactory at the present moment, the development of this project should be revised and adjusted based on the evaluations already made, including a greater detailing of environmental components, principally with respect to soil and topography.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.3
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• pp.69-81
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• 2009

This study was intended to evaluate the objective landscape of rural region using an additive integration index method in the Seondong region of Gochang-gun, Jeollabuk-do, Korea. This study consisted of the following three steps. First, this study developed an additive integration index calculation model for landscape assessment based on indicators and weight to each space type in accordance with three landscape fields which were developed by the expert Delphi method. Second, this study used NDVI (Normalized Difference Vegetation Index) and permeable area rate, which were available from high resolution satellite image, to calculate the green naturality degree, area rate, and building coverage respectively. Third, this study has calculated the landscape assessment index of rural regions using an additive integration index method made of assessment data and weight for each indicator. This study has found the following results: 1) landscape level was very poor in all 6 types of space, marking grade five; 2) while the highest level of natural landscape and mixed landscape was grade two, that of artificial landscape was grade five; 3) based on objective landscape, grade five showed the highest frequency, and grade one, two, three, and four followed in that order.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.355-362
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• 2011

Bog bean (Menyanthes trifoliata L.) is an endangered species in Korea and a perennial macrophyte with long rhizome, inhabiting in oligotrophic fen or edges of montane lakes. To decide appropriate substrate type for restoration of this plant, we investigated the effect of substrates (e.g. water, Sphagnum mat, paddy soil) on growth of bog bean. There were two water conditions on paddy soils: saturated and flooded. We planted 10cm rhizome in mesocosms and measured coverage, leaf area, leaf number and rhizome biomass. Bog bean growed until August in water and Sphagnum mat and until October in paddy soil. Rhizome biomass at the end of November were 49, 77, 239, and 312g in water, Sphagnum mat, paddy soil with water saturated, and paddy soil with water flooded conditions, respectively. The results indicate that bog bean can grow better in paddy soil which have higher nutrient than water or Sphagnum mat which represents natural habitat condition of bog bean. This reveals that actual ecological niche of bog bean is different from fundamental ecological niche in substrate. For successful restoration of bog bean in nutrient rich area, it is necessary to know the competitiveness of bog bean in various substrate conditions.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.246-246
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• 2012

Smart catalyst design though novel catalyst preparation methods can improve catalytic activity of transition metals on reducible oxide supports such as titania by enhancement of metal oxide interface effects. In this work, we investigated Pt nanoparticles/titania catalysts under CO oxidation reaction by using novel preparation methods in order to enhance its catalytic activity by optimizing metal oxide interface. Arc plasma deposition (APD) and metal impregnation techniques are employed to achieve Pt metal deposition on titania supports which are prepared by multi-target sputtering and Sol-gel techniques. In order to tailor metal-support interface for catalytic CO oxidation reaction, Pt nanoparticles and thin films are deposited in varying surface coverages on sputtered titania films using APD. To assess the role of oxide support at the interface, APD-Pt is deposited on sputtered and Sol-gel prepared titania films. Lastly, characteristics of APD-Pt process are compared with Pt impregnation technique. Our results show that activity of Pt nanoparticles is improved when supported over Sol-Gel prepared titania than sputtered titania film. It is suggested that this enhanced activity can be partly ascribed to a very rough titania surface with the higher free metal surface area and higher number of sites at the interface between the metal and the support. Also, APD-Pt shows superior catalytic activity under CO oxidation as compared to Pt impregnation on sputtered titania support. XPS results show that bulk oxide is formed on Pt when deposited through impregnation and has higher proportion of oxidized Pt in the form of $Pt^{2+/4+}$ oxidation states than Pt metal. APD-Pt shows, however, mild oxidation with large proportion of active Pt metal. APD-Pt also shows trend of increasing CO oxidation activity with number of shots. The activity continues to increase with surface coverage beyond 100%, thus suggesting a very rough and porous Pt films with higher active surface metal sites due to an increased surface area available for the reactant CO and $O_2$ molecules. The results suggest a novel approach for systematic investigation into metal oxide interface by rational catalysts design which can be extended to other metal-support systems in the future.