• Journal of Korean Dental Science
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• v.17 no.2
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• pp.53-63
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• 2024

Purpose: To investigate the effects of simultaneous soft and hard tissue augmentation and the addition of polydeoxyribonucleotide (PDRN) on regenerative outcomes. Materials and Methods: In five mongrel dogs, chronic ridge defects were established in both mandibles. Six implants were placed in the mandible, producing buccal dehiscence defects. The implants were randomly allocated to one of the following groups: 1) control: no treatment; 2) GBR: guided bone regeneration (GBR) only; 3) GBR/PDRN: GBR+PDRN application to bone substitute particles; 4) GBR/CTG: GBR+connective tissue grafting (CTG); 5) GBR/VCMX: GBR+soft tissue augmentation using volume stable collagen matrix (VCMX); and 6) group GBR/VCMX/PDRN: GBR+VCMX soaked with PDRN. The healing abutments were connected to the implants to provide additional room for tissue regeneration. Submerged healing was achieved. The animals were euthanized after four months. Histological and histomorphometric analyses were then performed. Results: Healing abutments were gradually exposed during the healing period. Histologically, minimal new bone formation was observed in the dehiscence defects. No specific differences were found between the groups regarding collagen fiber orientation and density in the augmented area. No traces of CTG or VCMX were detected. Histomorphometrically, the mean tissue thickness was greater in the control group than in the other groups above the implant shoulder (IS). Below the IS level, the CTG and PDRN groups exhibited more favorable tissue thickness than the other groups. Conclusion: Failure of submerged healing after tissue augmentation deteriorated the tissue contour. PDRN appears to have a positive effect on soft tissues.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.1
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• pp.123-130
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• 2006

The duties of the restorative materials are to bear up against stress and to protect reinforcement corrosion. So the restorative materials are estimated by various kinds of strength, permeability and etc, But, in case of existing performance evaluation of restorative materials, because various deterioration factors are separately acted, the system of performance evaluation is different from that of combined deterioration of real structure and it is difficult to evaluate the exact performance of restorative materials. In this study, to evaluate Performance of restorative materials, we compare their korea standard properties in terms of compressive and bending strength and permeability of water and air with real durability for carbonation, salt damage and actual reinforcement corrosion like ratio of corrosion area. weight reduction and corrosion velocity of steel bar under environment of combined deterioration. The results showed that strength and permeability of restorative materials are similar but their resistance to carbonation, salt damage and actual reinforcement corrosion are very different.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.1
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• pp.56-71
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• 2023

Citizens' needs for urban green spaces are on the rise due to improved quality of life and increased interest in environments. The garden is noteworthy because it is small in size, making it less controversial to create in the city, and it is adjacent to the residential area, improving citizens' daily environment. Moreover, recently gardens is attracting attention as a tool for urban regeneration, such as being created in declining areas as part of a government project. Therefore, it is time to study the role and value of urban gardens in deteriorated areas in terms of space welfare. However, there are few studies that quantitatively evaluate the effects of gardens, and many prior studies are limited to focusing the green space larger than a certain size (e.g., parks and forests). Therefore, the aim of this study is to examine the effect of garden and gardening quantitatively, paying attention to social aspects such as life satisfaction and community of inhabitants. The study was conducted in an old row housing complex in Gojan1-dong, Ansan-si, Gyeonggi-do. In there, some of the dwellers voluntarily created outdoor gardens and engaged in gardening for a long time. In addition, after the 2017 Gyeonggi-do Garden Fair, several gardens have been maintained and used by residents there. For the first step, the field trip was done to research the status of the garden in the area, and then, a survey was conducted on whether or not gardening has an impact on the life satisfaction and community of residents. The results were analyzed by t-test and ANOVA. As a result, residents who are engaged in gardening are more active in the "neighborhood exchange" and "resident participation" than those who are not engaged in gardening. In addition, if residents voluntarily create a garden, the level of "satisfaction of life" is higher than those staying in the garden which is constructed by the government. And a resident who is gardening in the complex shows higher life satisfaction than those who garden outside of the complex. These results confirmed that the garden has positive effects promoting "exchanges with neighbors", "participation in the community", and "life satisfaction" of residents. It shows that it is important to ensure the right of residents to participate in the garden-making process as much as possible, and the garden's location should be paid attention to maximize the positive effect of gardens.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.4
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• pp.421-431
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• 2023

Sewer deterioration models can offer important information on prediction of future condition of the asset to decision makers in their implementing sewer pipe networks management program. In this study, Markov chain model was used to estimate sewer deterioration trend based on the historical structural condition assessment data obtained by CCTV inspection. The data used in this study were limited to Hume pipe with diameter of 450 mm and 600 mm in three sub-catchment areas in city A, which were collected by CCTV inspection projects performed in 1998-1999 and 2010-2011. As a result, it was found that sewers in sub-catchment area EM have deteriorated faster than those in other two sub-catchments. Various main defects were to generate in 29% of 450 mm sewers and 38% of 600 mm in 35 years after the installation, while serious failure in 62% of 450 mm sewers and 74% of 600 mm in 100 years after the installation in sub-catchment area EM. In sub-catchment area SN, main defects were to generate in 26% of 450 mm sewers and 35% of 600 mm in 35 years after the installation, while in sub-catchment area HK main defects were to generate in 27% of 450 mm sewers and 37% of 600 mm in 35 years after the installation. Larger sewer pipes of 600 mm were found to deteriorate faster than smaller sewer pipes of 450 mm by about 12 years. Assuming that the percentage of main defects generation could be set as 40% to estimate the life expectancy of the sewers, it was estimated as 60 years in sub-catchment area SN, 42 years in sub-catchment area EM, 59 years in sub-catchment area HK for 450 mm sewer pipes, respectively. For 600 mm sewer pipes, on the other hand, it was estimated as 43 years, 34 years, 39 years in sub-catchment areas SN, EM, and HK, respectively.

• Journal of Chest Surgery
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• v.35 no.8
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• pp.580-583
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• 2002

Background: Obtaining precise hemodynamic and morphological information in the early postoperative period after surgical correction of congenital heart disease is important in determining the need for future medical or surgical intervention. We investigated the residual shunting after surgical repair of simple ventricular septal defect in order to know the incidence of residual shunting in the postoperative period and the natural history of small residual shunts located in the peripatch area. Material and Method: Forty three consecutive patients under one year of age who underwent patch repair of a simple ventricular septal defect were evaluated for incidence of residual shunts by echocardiography. Result: Eleven patients had echocardiographic residual shunt in the peripatch area at immediate postoperative period, however, there were no patients who needed reoperation due to deteriorated hemodynamic effect of residual shunt. The incidence of residual shunts was not significantly different with type of ventricular septal defect and material used for closure. During follow up period, two patients were lost and remaining nine patients no longer showed evidence of residual shunt. The mean time of last evidence of shunt was $4.2{\pm}3.6$ months after operation. Conclusion: Residual peripatch shunt flow was frequently noted in the immediate postoperative period following surgical repair of ventricular septal defect, however, most of them were disappeared within six months.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.570-576
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• 2020

This study uses beacons and smartphone Global Positioning System (GPS) receivers to establish a location-based disaster/hazard prediction system. Beacons are usually installed indoors to locate users using triangulation in the room, but this study is differentiated from previous studies because the system is used outdoors to collect information on registration location and temperature and humidity in hazardous areas. In addition, since it is installed outdoors, waterproof, dehumidifying, and dustproof functions in the beacons themselves are required, and in case of heat and humidity, the sensor must be exposed to the outside, so the waterproof function is supplemented with a separate container. Based on these functions, information on declining and vulnerable areas is identified in real time, and temperature/humidity information is collected. We also propose a system that provides weather and fine-dust information for the area concerned. User location data are acquired through beacons and smartphone GPS receivers, and when users transmit from declining or vulnerable areas, they can establish the data to identify dangerous areas. In addition, temperature/humidity data in a microspace can be collected and utilized to build data to cope with climate change. Data can be used to identify specific areas of decline in a microspace, and various analyses can be made through the accumulated data.

• Journal of the Korean association of regional geographers
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• v.1 no.1
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• pp.81-91
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• 1995

Modern geography in France since the end of 19th century was begun with regional geography. France after losing the Franco-Prussian war in 1871 had tried to regain the deteriorated national proudness through the colonial expansion. The social and historical contexts in France had encouraged French geographers to engage in detailed small area studies. In particular, after Blache became a faculty at Sorbonne University his idea on integrative rather than selective description on area studies had gained paradigmatic popularity not only in geography but in other disciplines. The regional geography tradition was then firmly established as a science and as an art by Vidalian school until the beginning of Second World War. However, when industrialization and urbanization were the dominant science since the 1950s spatial analytic geography has become popular research tradition replacing the previledged regional geography. Nevertheless, geography in France is still acknowledged as an interesting and valuable discipline since regional geography tradition had accumulated rich knowledges on various regions. As regional geography provides valuable information and helps to understand various world regions, it should be regenerated as a research tradition which are able to fulfill societal needs accruing nowadays. By doing this, geography can rectify its disciplinary identity which has been disintegrated internally by giving too much emphasis on specialties, and melding into nearby disciplines. Our geography education for the chorography in particular focuses mainly on the listings of simple geographic facts, in this regard. Rather than attracting students' concern and motivation, geography is considered as a subject oriented toward simply memorizing geographic facts. To overcome these problems, regional geography should be discussed openly and popularized in research. Regional geographic methods available and results produced in other countries should be introduced, and critical assessments should be made for selective acknowledgment for nurturing our regional geography.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.1
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• pp.165-171
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• 2000

The purpose of this study is to determine the prevalence of cataracts in a rural area of Kyung-Buk province. Cataract is the main cause of blindness and visual impairment in the world. Recently, the number of age-related cataract surgeries has increased remarkably. In spite of such an increase in the number of patients, there are still many cataract patients with highly deteriorated visual function who have had no occasion to receive an ocular examination. In order to screen such patients the author assessed 636 individual(1272 eyes) aged 50 years or more who had wanted to be examined generally in two area. Chilgok and Munkyung, Kyung-Buk province using a simplified cataract screening system recently proposed by Sasaki et al. Kanazawa Medical University in Japan. The results obtained are as follows. The number of visual impairment patients in this study group was 493(77.5%). They were screened by cataract screening system. Primary screening examination detected 448 subjects to be suspected of cataract while the subsequent secondary examination narrowed this number of subjects to 308(48.4%). Final number of subjects to be diagnosed of cataract was 421(66.2%). The rate of incidence, according to the age, was 27.5% in the 50 year-olds age group, 62.5% in the 60's age group, 86.1% in the 70's age group and 94.3% in the 80's age group and upwards. This results concluded that cataract is the main cause of blindness and visual impairment and is an important public eye health care problem of aged population in rural Korea. Methods of tackling the cataract problem(both backlog and incident), and other eye health needs are recommended. The need to extend eye health service to the rural areas is emphasized.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.1
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• pp.1-14
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• 2017

A land cover map provides basic information to help understand the current state of a region, but its utilization in the ecological research field has deteriorated due to limited temporal and spatial resolutions. The purpose of this study was to investigate the possibility of using a land cover map with data based on high resolution images acquired by UAV. Using the UAV, 10.5 cm orthoimages were obtained from the $2.5km^2$ study area, and land cover maps were obtained from object-based and pixel-based classification for comparison and analysis. From accuracy verification, classification accuracy was shown to be high, with a Kappa of 0.77 for the pixel-based classification and a Kappa of 0.82 for the object-based classification. The overall area ratios were similar, and good classification results were found in grasslands and wetlands. The optimal image segmentation weights for object-based classification were Scale=150, Shape=0.5, Compactness=0.5, and Color=1. Scale was the most influential factor in the weight selection process. Compared with the pixel-based classification, the object-based classification provides results that are easy to read because there is a clear boundary between objects. Compared with the land cover map from the Ministry of Environment (subdivision), it was effective for natural areas (forests, grasslands, wetlands, etc.) but not developed areas (roads, buildings, etc.). The application of an object-based classification method for land cover using UAV images can contribute to the field of ecological research with its advantages of rapidly updated data, good accuracy, and economical efficiency.

• Korean Journal of Environment and Ecology
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• v.18 no.4
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• pp.359-368
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• 2004

The purpose of this study is to examine distribution and damages of the trails of inquiry of urban natural parks. Those parks were located at south-north green corridor at Incheon being mountainous type of urban natural parks that were core area of urban ecosystem preservation to of urban natural parks that citizens recently made use of them as nature experience type of leisure and recreation place from time to time, and to supply basic material deciding on the ways to improve the trails of nature preservation type. The survey sites included Geyang Park, Baekma Park, Yaksa Park, Munhak Park and Cheongryang Park. The number of main trails was 42 at Geyang Park, 43 at Baekma Park, 9 at Yaksa Park, 28 at Munhak Park, and 22 at Cheongryang Park, and it was excessively more than optimum needed: The number of branch trails of the parks seemed to increase. The bared trail width in average of the roads was 3.5m, while maximum depth in average was 21.3cm. The trails were thought to be deteriorated rapidly without systematic maintenance. The 5th and 6th grade of the impact rating class that required restoration because of serious deterioration occupied 19.6∼78.0%. Based on the findings, the study suggested ways to improve and manage the trails of inquiry of urban natural parks that were placed at south-north green corridor at Incheon.