• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.589-595
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• 2007

Korea Railroad Research Institute has developed the driverless rubber-tired K-AGT (Korean-Automated Guideway Transit) system from 1999 to 2005 and has done its performance and reliability tests on the test line at Gyeongsan-city. Radio Frequency Communication-Based Train Control system of K-AGT, which employed Advanced Automated Train Control scheme, detects train position using the radio propagation delay between wayside and vehicle radio equipment. In this paper, we investigate whether the transmission power of radio system can be reduced to the permitted level announced by the Ministry of Information and Communication for license-free ISM(Industrial Scientific Medical) frequency bands. We first determine radio propagation model, using the measured data at test line, and perform simulation for radio coverage prediction. From the simulation results, we identify that the radio system operated with reduced power can provide good link quality in total test line.

• Journal of Periodontal and Implant Science
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• v.51 no.2
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• pp.77-87
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• 2021

Purpose: The aim of this study was to compare the efficacy of the tunnel technique for root coverage using a new xenogeneic acellular dermal matrix vs. connective tissue grafting (CTG) for the treatment of multiple maxillary adjacent recessions (recession type 1) at 12 months postoperatively. Methods: This study enrolled 12 patients with at least 3 contiguous, bilateral, symmetrical maxillary gingival recessions (i.e., at least 6 recessions per patient). In total, 74 recessions were treated using the modified coronally advanced tunnel (MCAT) technique combined with a novel porcine-derived acellular dermal matrix (PADM) at 37 test sites or CTG at 37 control sites. The following clinical parameters were measured: recession height, clinical attachment level, width of keratinized tissue, probing depth, recession width, gingival thickness, mean root coverage (MRC), and complete root coverage (CRC). Comparisons between test and control groups were made for pain visual analog scale scores at 14 days. Results: At 12 months, the MCAT with PADM (test) yielded a statistically significant improvement in all clinical parameters studied. MRC was significantly higher on the control sides (80.6%±23.7%) than on the test sides (68.8%±23.4%). Similarly, CRC was 48.7%±6.8% on the control sides (CTG), in contrast to 24.3%±8.2% on the test sides (PADM). Statistically significant differences were observed in favor of the control sides for all clinical parameters studied. Nevertheless, the MCAT in adjunction with PADM was clearly superior at reducing mean and maximum patient-reported postoperative pain intensity and pain duration in the first week after surgery. Conclusions: The use of PADM to treat multiple recessions improved clinical parameters at 12 months, but these outcomes were nevertheless poorer than those observed for CTG. However, PADM reduced morbidity, particularly the pain experienced by patients.

• Archives of Plastic Surgery
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• v.50 no.6
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• pp.593-600
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• 2023

Background Soft tissue reconstruction around the knee area is still an open question, particularly in persistent infections and multiple reoperations scenario. Flap coverage should guarantee jointmobility and protection, even when foreign materials are implanted. The chimeric harvesting of the musculocutaneous gastrocnemius flap, based on the sural artery perforators, can extend its applicability in soft tissue reconstruction of the upper leg, overcoming the drawbacks of the alternative pedicled flaps. Methods A multicenter retrospective study was conducted enrolling patients who underwent to a pedicled, chimeric gastrocnemius musculocutaneous-medial sural artery perforator (GM-MSAP) or lateral sural artery perforator (GM-LSAP) flap for knee coverage in total knee arthroplasty (TKA) recurrent infections and oncological or traumatic defects of the upper leg from 2018 to 2021. Outcomes evaluated were the successful soft tissue reconstruction and flap complications. Surgical timing, reconstruction planning, technique, and rehabilitation protocols were discussed. Results Twenty-one patients were included in the study. Nineteen GM-MSAPs and 2 GM-LSAPs were performed (soft tissue reconstruction in infected TKA [12], in infected hardware [4], and in oncological patients [5]). Donor site was closed primarily in 9 cases, whereas a skin graft was required in 12. Flap wound dehiscence (1), distal flap necrosis (1), distal necrosis of the skin paddle (1), and donor site infection (1) were the encountered complications. Flap reraise associated to implant exchange or extensive debridement was successful without requiring any further flap surgery. Conclusion The propeller-perforator GM-MSAP offers qualitative defect coverage and easiness of multiple flap reraise due to skin availability and its laxity.

• Korean Journal of Environment and Ecology
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• v.22 no.5
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• pp.471-480
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• 2008

This study was conducted to investigate the characteristics of breeding bird community in relation to altitude and vegetation in Jirisan National Park. The survey was carried over 4 study sites by point counts method to figure out habitat environment and breeding bird community from March to August in 2006. The study results are summarized as follows: Total 32 species were recorded, and 27 species and density of 37.31 ea/ha in low altitude mixed forest, 23 species and 34.99 ea/ha in low altitude deciduous forest, 18 species and 23.95 ea/ha in high altitude mixed forest, 19 species and 20.21 ea/ha in high altitude deciduous forest, respectively. Eleven species were observed only in the low altitude sites, 4 species were observed only in the high altitude sites. Number of species and density were high in the low altitude sites, and they were high in the mixed forests. In nesting guild analysis, the low altitude sites are similarly found species number of three types but canopy nesting species in the high altitude sites are advent less. In foraging guild analysis, the species number of canopy foraging appeared most highly in all study sites. In the difference analysis of each species density. Four species which are showed the difference in the low altitude sites, owing to vegetation. Long-tailed Tit(Aegithalos caudatus) and Great tit(Parus major) are difference because of difference in volume of canopy layer, and Coal Tit(Parus ater) was difference because of coniferous forest preference quality. Four species(Hazel Grouse, Winter Wren, Pale Thrush, Yellow-throated Bunting) which are showed the difference of the density in the high altitude sites because of thick growth of the bush layer. Ten species which are showed the difference in study sites, owing to altitude. Oriental Cuckoo(Cuculus saturatus), Winter Wren(Troglodytes troglodytes), Siberian Blue Robin(Luscinia cyane), Arctic Warbler(Phylloscopus borealis), Coal Tit(Parus ater), and Yellow-throated Bunting(Emberiza elegans) appeared highly in the high altitude sites, Pale Thrush(Turdus pallidus), Long-taild Tit(Aegithalos caudatus), Varied Tit(Parus varius), and Eurasian Nuthatch(Sitta europaea) appeared highly in the low altitude sites. It seems that bush layer coverage volume and canopy layer total coverage volume do influences on the breeding bird community, because the bush layer was thick growth, and canopy layer coverage volume was difference. It would be needed the management and maintenance of bush layer coverage volume and canopy layer with multi-layer structure to increase foliage height diversity and total coverage volume for the protection and management of bird community in Jirisan National Park.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.4
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• pp.275-283
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• 2015

The aim of this study is to estimate the noise exposure of roadside apartment complex according to the characteristics of apartment complex. The facade noise level of residential buildings and the ground noise level inside apartment complexes were predicted and analyzed using noise mapping based on a computerized noise model. In addition, the correlation analysis between these noise levels and the characteristics of apartment complex such as traffic volume, building coverage, the number of adjacent roads, etc. was done in a total of 21 apartment complexes. The results showed that building facade noise level and ground noise level were positively correlated with traffic volume (correlation coefficient, r=0.616~0.623) and the number of adjacent roads (r=0.340~0.496). On the other hand, they were negatively correlated with building coverage (r=-0.413~-0.477) and complex area per the number of roads (r=-0.478~-0.615).

• Journal of Preventive Medicine and Public Health
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• v.53 no.4
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• pp.220-227
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• 2020

Objectives: The aim of this study was to assess how different social determinants of health (SDoH) may be related to variability in coronavirus disease 2019 (COVID-19) rates in cities and towns in Massachusetts (MA). Methods: Data about the total number of cases, tests, and rates of COVID-19 as of June 10, 2020 were obtained for cities and towns in MA. The data on COVID-19 were matched with data on various SDoH variables at the city and town level from the American Community Survey. These variables included information about income, poverty, employment, renting, and insurance coverage. We compared COVID-19 rates according to these SDoH variables. Results: There were clear gradients in the rates of COVID-19 according to SDoH variables. Communities with more poverty, lower income, lower insurance coverage, more unemployment, and a higher percentage of the workforce employed in essential services, including healthcare, had higher rates of COVID-19. Most of these differences were not accounted for by different rates of testing in these cities and towns. Conclusions: SDoH variables may explain some of the variability in the risk of COVID-19 across cities and towns in MA. Data about SDoH should be part of the standard surveillance for COVID-19. Efforts should be made to address social factors that may be putting communities at an elevated risk.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.3
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• pp.9-17
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• 2017

Incheon International Airport is total number of passengers using that increased by 8.3 percent year-on-year, with the highest level of user ratings since the opening of the previous year. Thus, After analyzing the positive image of Incheon International Airport and analyzing future corporate image development, the company conducted a study on improving the image of Incheon International Airport. Based on the SERVQUAL method, the study classified the five types of SERVQUAL. The difference in the distinctions of the media coverage varied, and the differences in the credibility of the media show that the differences between the press and the credibility of the media are not reflected in the characteristics of the media. These findings will provide data for the managerial control of corporate images based on positive or negative reporting on the Incheon International Airport, and based on the analysis of the findings, it is believed that it will benefit from being the most high-profile airport.

• JSTS:Journal of Semiconductor Technology and Science
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• v.17 no.1
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• pp.56-64
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• 2017

In this paper, an advanced ZigBee (AZB) system for internet-of-things (IoT) applications is proposed which can support various data rates from 31.25 Kbps to 2 Mbps, and the implementation results of the AZB baseband processor are presented. Repetition coding for 32-chip direct-sequence spread spectrum (DSSS) symbol is applied for low rates under 250 Kbps to extend the coverage. Convolution coding, puncturing, and interleaving for non-DSSS symbol are performed for high rates from 500 Kbps to 2 Mbps for multi-media services. Simulation results show that the coverage increases at the rate of 51.8-77.3% for various environments compared with IEEE 802.15.4 ZigBee. AZB baseband processor was implemented in 180 nm CMOS process and total gate counts are 260K with the size of $5.8mm^2$.

• Health Policy and Management
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• v.19 no.4
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• pp.53-65
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• 2009

Purpose: This study was conducted to identify the prenatal heath care utilization and expenditure among pregnant women. Method: This was a 5-month follow-up study using a stratified sampling and the data were drawn from the "nationwide claim database of Korean National Health Insurance Corporation". Result: This study found that pregnant women were first diagnosed with pregnancy when they were 7.1 weeks pregnant, received 12.7 times of prenatal examinations and 10.6 times of ultrasonogram. It was revealed that 67.5% of the subjects continued to receive prenatal care at the same medical institutions from the diagnosis of pregnancy to the delivery. The study also showed that the total expenditure of prenatal care per pregnant woman was 700,000 Korean Won (KRW) on average and the insurance coverage rate stood at only 20%. Pregnant women living in metropolitan area spent more on prenatal healthcare expenditure than those who living in medium-sized city or rural area. Conclusion: The results of this study implies that the government needs to provide pregnant women with continuous support by increasing health insurance coverage for prenatal care. Especially, it is considered to provide more support to the pregnant women residing in medically underserved areas.

• Korean Journal of Clinical Pharmacy
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• v.30 no.3
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• pp.177-184
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• 2020

Background & objective: The Korean government has expanded its benefit coverage to enhance patients' access to orphan drugs and cancer medicines. However, the number of new drugs whose indications were not applied to reimbursement in health insurance was increased. This study aimed to understand the perspectives of experts and various stakeholders on the introduction of a new funding program for cancer treatment and orphan drugs. Methods: We conducted email surveys comprising 19 questions, from September 9 to 26, 2016. We distributed questionnaires to members of the Pharmaceutical Benefit Appraisal Committee and Cancer Assessment Committee. We also conducted a qualitative study through group interviews with stakeholders, including pharmaceutical companies and some patient groups for diseases. Results: A total of 35 survey respondents recommended the introduction of a funding program for orphan drugs, whereas 66% recommended the launch of funding for anticancer drugs. In addition, most pharmaceutical companies and patient groups recommended the introduction of new funding programs targeting patients with cancer and rare diseases. However, some participants asserted that it would be more appropriate to modify the existing reimbursement scheme than launch new funding. Conclusion: This study concluded that introducing new funding needs a social consensus to relieve financial hardships at the patient level.