• Journal of Korean Society for Geospatial Information Science
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• v.24 no.1
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• pp.43-50
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• 2016

Urbanization in Korea has increased significantly and subsequently, various facilities have been concentrated in urban areas at high speed in accordance with a growing urban population. Accordingly, damages have occurred due to a variety of disasters. In particular, fire damage among the social disasters caused the most severe damage in urban areas along with traffic accidents. 44,432 cases of fire occurred in 2015 in Korea. Due to these accidents, 253 were killed and property damage of 4,50 billion won was generated. However, despite the efforts to reduce a variety of damage, fire danger still remains high. In this regard, this study collected fire data, generated from 2007 to 2014 through the Jinju Fire Department and the National Fire Data System(NFDS) and calculated fire risk by analyzing the clustering of fire cases and facilities in Jinju-si based on the current DB of facilities, offered by the Ministry of Government Administration and Home Affairs. As a result, the risk ratings of fire occurrence were classified as four stages under the standards of the US Society of Fire Protection Engineers(SEPE). Business facilities, entertainment facilities, and automobile facilities were classified as the highest A grade, detached houses, Apartment houses, education facilities, sales facilities, accommodation, set of facilities, medical facilities, industrial facilities, and life service facilities were classified as U grade, and other facilities were classified as EU grade. Finally, hazardous production facilities were classified as BEU grade, the lowest grade. In addition, in the case of setting the standard with loss of life, the highest risk facility was the hazardous production facilities, while in the case of setting the standard with property damage, a set of facilities and industrial facilities showed the highest risk. In this regard, this study is expected to be effectively utilized to establish the fire reduction measures against facilities, distributed in urban space by calculating risk grades regarding the generation frequency, casualties, and property damage, through the classification of fire, occurred in the city, according to the facilities.

• Journal of Ecology and Environment
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• v.32 no.2
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• pp.67-73
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• 2009

Soil $CO_2$ efflux can vary markedly in magnitude over both time and space, and understanding this variation is crucial for the correct measurement of $CO_2$ efflux in ecological studies. Although considerable research has quantified temporal variability in this flux, comparatively little effort has focused on its spatial variability. To account for spatial heterogeneity, we must be able to determine the number of sampling points required to adequately estimate soil $CO_2$ efflux in a target ecosystem. In this paper, we report the results of a study of the number of sampling points required for estimating soil $CO_2$ efflux using a closed-dynamic chamber in young and old Japanese cedar plantations in central Japan. The spatial heterogeneity in soil $CO_2$ efflux was significantly higher in the mature plantation than in the young stand. In the young plantation, 95% of samples of 9 randomly-chosen flux measurements from a population of 16 measurements made using 72-$cm^2$ chambers produced flux estimates within 20% of the full-population mean. In the mature plantation, 20 sampling points are required to achieve means within $\pm$ 20% of the full-population mean (15 measurements) for 95% of the sample dates. Variation in soil temperature and moisture could not explain the observed spatial variation in soil $CO_2$ efflux, even though both parameters are a good predictor of temporal variation in $CO_2$ efflux. Our results and those of previous studies suggest that, on average, approximately 46 sampling points are required to estimate the mean and variance of soil $CO_2$ flux in temperate and boreal forests to a precision of $\pm$ 10% at the 95% confidence level, and 12 points are required to achieve a precision of $\pm$ 20%.

• Journal of the Korean association of regional geographers
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• v.21 no.3
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• pp.593-607
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• 2015

This study examined the Holocene environmental changes by OSL dating and magnetic susceptibility (MS) in 12 sediment cores from estuarine tidal flat, Mosan Bay Estuary, west coast of Korea. For the complexity of the geomorphic characteristics of estuaries, it is difficult to obtain a series of data. The following significant results were derived using relatively simple methods. First, MS data shows sensitive changes in pattern according to the precipitation change during mid to late Holocene. Second, MS data show periodicity of 250 yr. when they were wavelet transformed. This periodicity is related with the intensifying of solar intensity, the East Asian Summer Monsoon and ENSO. Thus, MS data from estuarine sediments are valuable data which can explain mechanism of climate change in East Asia and worthy as proxy data.

• Journal of KIISE:Software and Applications
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• v.30 no.5_6
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• pp.540-549
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• 2003

In collaborative recommendation two models are generally used: the user model and the article model. A user model learns correlation between users preferences and recommends an article based on other users preferences for the article. Similarly, an article model learns correlation between preferences for articles and recommends an article based on the target user's preference for other articles. In this paper, we investigates various combination methods of the user model and the article model for better recommendation performance. They include simple sequential and parallel methods, perceptron, multi-layer perceptron, fuzzy rules, and BKS. We adopt the multi-layer perceptron for training each of the user and article models. The multi-layer perceptron has several advantages over other methods such as the nearest neighbor method and the association rule method. It can learn weights between correlated items and it can handle easily both of symbolic and numeric data. The combined models outperform any of the basic models and our experiments show that the multi-layer perceptron is the most efficient combination method among them.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.3
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• pp.566-582
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• 2016

This study aims to analyze knowledge extension and diffusion trend among industries through technological convergence in non-Capital rural areas. A case of Sunchang, Korea examines knowledge extension trend of fermented soy product manufacturing industry. Patent application data are used to make technology convergence analysis and knowledge network analysis. Patent analysis results show that there are differences of knowledge extension trend between the whole country and Sunchang. Technologies of fermented soy product manufacturing in Sunchang is inclined to extend toward technologies related to fermented microorganism. Contrary to the whole country, knowledge extension in rural area like Sunchang is converged to technologies suitable for specialized but limited regional assets and human resources. Core actors of knowledge network of fermented soy product manufacturing in Sunchang are mainly public organizations such as local government, universities, and agencies or institutes. Recently technology sharing and extension is likely to occur through the cooperation between associative corporations and public organizations.

• Journal of Veterinary Clinics
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• v.25 no.3
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• pp.187-191
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• 2008

A 7-year-old, intact female Yorkshire terrier dog was presented for coughing, anorexia, chest pain and dyspnea. Right lateral thoracic radiograph demonstrated a large mass shape on the heart base with decreased cardiac silhouette and severe right deviation of the trachea with the heart shifted to the left thoracic wall was observed on the ventrodorsal thoracic projection. Echocardiographic examination revealed a large rounded mass compressing left atrium around the heart base without signs of pericardial effusion. On computed tomographic (CT) findings, sagittal CT images depicted the possibility of cranial vena caval invasion and heart base involvement of the mass associated with biatrial compression. Dorsal CT image revealed the right deviation of trachea due to the heart base mass and markedly shrunk lung space was detected on the transverse CT image. Because the dog suddenly had died during the recovery from anesthesia after finishing CT scan, necropsy was performed. On gross findings, a large and lobulated mass was located at the base of the heart. A poorly-demarcated, infiltrative, multilobulated tumor composed of polyhedral cells in solid cellular sheets was confirmed based on histopathologic examination. This dog was diagnosed as a chemodectoma. This case report describes the clinical findings, diagnostic consistency of thoracic radiography, echocardiography and CT, and histopathologic confirmation in a spontaneously occurring chemodectoma with a Yorkshire terrier dog.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.1
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• pp.1-14
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• 2009

Wind energy has been recognized as one of the most important and fastest growing energy resources without emission of air pollutant. Thus, it is necessary to predict wind speed and direction accurately both in time and space toward the efficient usage of wind energy. Numerical simulation experiments using the Fifth-Generation Mesoscale Model (MM5) are carried out to clarify the impact of surface observation data assimilation on the estimation of wind energy resources. The EXP_Radius run was designed with respect to the radius of influence in the Four-Dimensional Data Assimilation (FDDA), and the EXP_Impact run was made by changing the nudging coefficient that determines the relative magnitude of the nudging term. The simulation period covers a clear-sky event on 3 - 5 June 2007 and another is on 2 - 4 December 2006. It is found that the simulated results are very sensitive to the radius of influence and nudging parameters in the FDDA. The further analysis of the results shows that the impact of the radius of influence tends to be stronger in weak synoptic flow episode than that in strong synoptic flows episode. The nudging factor is also sensitive to the intensity of the synoptic flows.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.5
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• pp.304-309
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• 2009

Purpose: Fibrous dysplasia (FD) is a fibro-osseous disease associated with activating missense mutations of the gene encoding the $\alpha$-subunit of stimulatory G protein. FD may affect a single bone (called monostotic form) or multiple bones (called polyostotic form). The extent of lesions reflects the onset time of mutation. In this study, cells from monostotic FD in maxilla of a patient were isolated and cultured in vitro for characterization. Materials and Methods: The single cells were released from FD lesion which was surgical specimen from 15 years-old boy. These isolated cells were cultured in vitro and tested their proliferation activity with MTT assay. In osteogenic media, these cells underwent differentiation process comparing with its normal counterpart i.e. bone marrow stromal cells. The proliferated FD cells were detached and transplanted into the dordsal pocket of nude mouse and harvested in 6 weeks and 12 weeks. Results and Summary: FD cells have an increased proliferation rate and poor differentiation. As a result, cells isolated from FD lesion decreased differentiation into osteoblast and increased proliferation capacity. MTT assay presented that proliferation rate of FD cells were higher than control. However, the mineral induction capacity of FD was lesser than that of control. Monostotic FD cells make fewer amounts of bone ossicles and most of them are woven bone rather than lamellar bone in vivo transplantation. In transplanted FD cells, hematopoietic marrow were not seen in the marrow space and filled with the organized fibrous tissue. Therefore, they were recapitulated to the original histological features of FD lesion. Collectively, these results indicated that the FD cells were shown that the increased proliferation and decreased differentiation potential. These in vitro and in vivo system can be useful to test FD cell's fate and possible.

• Journal of Periodontal and Implant Science
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• v.46 no.4
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• pp.244-253
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• 2016

Purpose: The aim of this study was to characterize the healing in the grafted calvarial defects of rats after adjunctive hyperbaric oxygen therapy. Methods: Twenty-eight male Sprague-Dawley rats (body weight, 250-300 g) were randomly divided into two treatment groups: with hyperbaric oxygen therapy (HBO; n=14) and without HBO (NHBO; n=14). Each group was further subdivided according to the bone substitute applied: biphasic calcium phosphate (BCP; n=7) and surface-modified BCP (mBCP; n=7). The mBCP comprised BCP coated with Escherichia-coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2) and epigallocatechin-3-gallate (EGCG). Two symmetrical circular defects (6-mm diameter) were created in the right and left parietal bones of each animal. One defect was assigned as a control defect and received no bone substitute, while the other defect was filled with either BCP or mBCP. The animals were allowed to heal for 4 weeks, during which those in the HBO group underwent 5 sessions of HBO. At 4 weeks, the animals were sacrificed, and the defects were harvested for histologic and histomorphometric analysis. Results: Well-maintained space was found in the grafted groups. Woven bone connected to and away from the defect margin was formed. More angiogenesis was found with HBO and EGCG/BMP-2 (P<0.05). None of the defects achieved complete defect closure. Increased new bone formation with HBO or EGCG/BMP-2 was evident in histologic evaluation, but it did not reach statistical significance in histometric analysis. A synergic effect between HBO and EGCG/BMP-2 was not found. Conclusions: Within the limitations of this study, the present findings indicate that adjunctive HBO and EGCG/BMP-2 could be beneficial for new bone formation in rat calvarial defects.

• Journal of the Korean Geographical Society
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• v.49 no.3
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• pp.472-487
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• 2014

This study aims to analyze the characteristics of GIS-related test items of high school Korean Geography in the 7th National Education Curriculum, and to discuss some issues and challenges. First, we developed a framework for analyzing test items based on the literature review and the content analysis on the textbooks, which categorizes test items in terms of content elements and activity elements. Then, we examined test items of nation-wide tests including CSAT(College Scholastic Ability Test) carried out 2004-2012 and analyzed the percentage of correct answers as well. According to the results, there was a significant predominance of particular test item categories, and the percentage of correct answers of GIS-related items was slightly higher than whole average but it depended on the test item categories. Finally, we discussed the implications of this analysis to the tests as well as the teaching-learning process in the classroom, and suggested improvement directions such as integration of GIS with other contents, reinforcement of the inquiry-based test items, maintaining moderate difficulty.