• Journal of Communications and Networks
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• v.14 no.5
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• pp.578-587
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• 2012

One of the key elements in the emerging, packet-based long term evolution (LTE) cellular systems is the deployment of multiple femtocells for the improvement of coverage and data rate. However, arbitrary overlaps in the coverage of these femtocells make the handover operation more complex and challenging. As the existing handover strategy of LTE systems considers only carrier to interference plus noise ratio (CINR), it often suffers from resource constraints in the target femtocell, thereby leading to handover failure. In this paper, we propose a new efficient, multi-objective handover solution for LTE cellular systems. The proposed solution considers multiple parameters like signal strength and available bandwidth in the selection of the optimal target cell. This results in a significant increase in the handover success rate, thereby reducing the blocking of handover and new sessions. The overall handover process is modeled and analyzed by a three-dimensional Markov chain. The analytical results for the major performance metrics closely resemble the simulation results. The simulation results show that the proposed multi-objective handover offers considerable improvement in the session blocking rates, session queuing delay, handover latency, and goodput during handover.

• Journal of the Korean Institute of Landscape Architecture
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• v.13 no.1
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• pp.67-77
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• 1985

The purpose of this study is to establish the principles of an arrangement planning for children's playgrounds which can be contributed to offer the recreation opportuqities to all urban children equally. The study is specially focused on the service radius and the inducement rate in children's playground. The data in this study were made into field survey, dividing the park users into preschool children (below 6- year-old)and school children (7 to 12-year - old), through six sampling places in Taegu City. The results are summarized as follows : The using distance was becoming shorter according as the dencity of population was becoming high. There wart 75% of the users to service radius 250m prescribing in the present City Park Law. The service radius of preschool children was 260m and that of school children was 300m in average. To investigate the effects of several attributes on the inducement of children's playground, three of six children's playgrounds were selected based on three attributes of those which were width of area, percentage of green coverage and the pattern of facility arrangment. Of three children's playgrounds, Sankyok 3- dong which had the highest percentage of green coverage, the greatest width of area and the corner type in the arrangement was a slight tendency to become the same in the inducement rate of the two age group. In the using pattern of this Sankyok 3-dong. preschool children usually used a play facility, on the contrary, school children showed the active play pattern by using space.

• Weed & Turfgrass Science
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• v.3 no.3
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• pp.240-245
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• 2014

This study was carried out to determine the possible use of volcano eruption sand at Merapi mountain area compared with clayey soil, alfisol as turfgrass growing media. Indonesia has abundant source of eruption sand and clayey soil. Native zoysiagrass (Z. matrella) was collected from Sleman district and seashore paspalum (P. vaginatum) from Solo region. The experimental plots were treated with both organic and inorganic fertilizers. Zoysiagrass and seashore paspalum can grow on the mixture of eruption volcano sand and alfisol soil. Fertilizers application increased turf color, surface coverage rate and recovery rate of turfgrass. While fertilizer treated alfisol have no effect on the length and dry weight of zoysiagrass root. Mixing of volcano eruption sand on growing media resulted in longer root length, higher shoot dry weight of zoysiagrass than in alfisol soil. Type of fertilizer affected the pH, soil organic matter, total N, available P, available K and electrical conductivity of sand and alfisol after cultivation. Similarly to zoysiagrass, the recovery of seashore paspalum was increased by application of fertilizer, even the inorganic fertilizer showed faster recovery than organic fertilizer. Surface coverage of seashore paspalum was faster than that of zoysiagrass with or without fertilizer.

• Progress in Medical Physics
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• v.31 no.4
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• pp.153-162
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• 2020

Purpose: We aim to evaluate the accuracy and effectiveness of an automatically converted radiation therapy plan between Radixact machines by comparing the original plan with the transferred plan. Methods: The study involved a total of 20 patients for each randomly selected treatment site who received radiation treatment with Radixact. We set up the cheese phantom (Gammex RMI, Middleton, WI, USA) with an Exradin A1SL ion chamber (Standard Imaging, Madison, WI, USA) and GAFCHROMIC EBT3 film (International Specialty Products, Wayne, NJ, USA) inserted. We used three methods to evaluate an automatically converted radiation therapy plan using the features of the Plan transfer. First, we evaluated and compared Planning target volume (PTV) coverage (homogeneity index, HI; conformity index, CI) and organs at risk (OAR) dose statistics. Second, we compared the absolute dose using an ion chamber. Lastly, we analyzed gamma passing rates using film. Results: Our results showed that the difference in PTV coverage was 1.72% in HI and 0.17% in CI, and majority of the difference in OAR was within 1% across all sites. The difference (%) in absolute dose values was averaging 0.74%. In addition, the gamma passing rate was 99.64% for 3%/3 mm and 97.08% for 2%/2 mm. Conclusions: The Plan transfer function can be reliably used in appropriate situations.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.21-30
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• 2020

In this paper, we predicted the propagation loss for the air-to-ground (A2G) channel between the ground control system and the unmanned aerial vehicle (UAV) using the prediction model for the aircraft recommended by the International Telecommunication Union (ITU). We analyzed the network coverage of the aerial relay system based on the medium altitude UAVs by expanding it into the air-to-air (A2A) channel. Climate and geographic factors in Korea were used to predict propagation loss due to atmospheres. We used the measured data published by the Telecommunication Technology Association (TTA) for regional rainfall-rate and effective earth radius factors to increase accuracy. In addition, the aerial relay communication system used the key parameter of the common data link (CDL) system developed in Korea recently. Prediction results show that the network coverage of the aerial relay system broadens at higher altitude.

• The Journal of Korean Medicine
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• v.39 no.3
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• pp.51-60
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• 2018

Objectives: This study aimed to investigate the opinions of Korean medical doctors on how to elucidate possible remedial measures for expanding the health insurance benefits coverage item of Korean medicine (KM). Methods: An online survey was conducted to all members who had registered e-mail address in the association of Korean medicine from 1 to 17 November, 2016. Statistical analysis was performed and odds ratio with 95% confidence interval were calculated by each subgroup. Results: A total of 743 members answered the questions and the response rate was 4.1%. The priorities for expanding health insurance benefits were as follows: thermographic imaging, Sasang constitution typing test, and pulse wave among examinations; pharamacopuncture, embedding acupuncture, and acupotomy among procedures; Chuna manual therapy, manual therapy for meridian muscle, and Daoyin exercise therapy among manual therapies; low-frequency electrical therapy, traction, paraffin bath, and light therapy among physical therapies; and aromatherapy, enema therapy, and color therapy among activities of KM. Conclusions: It should be covered by the national health insurance (NHI) of KM that thermographic imaging, pharmacoacupuncture, Chuna manual therapy, low-frequency electrical therapy, aromatherapy as a top priority. We also suggest that basic medical tests, such as blood, urine, or imaging, should be included in the coverage of the NHI of KM. It is necessary to review the expertise and public opinions about the plans and priorities for the conversion of the desired medical services to be covered by the NHI.

• Journal of the Korean Wood Science and Technology
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• v.46 no.6
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• pp.645-655
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• 2018

The use of wood waste as substrate for plant growth exemplifies a strategy for turning waste into resources. The overall objective of this research was to evaluate the effects of wood-based growing media on plant cover in a slope area. Moreover, we tried to find out what physicochemical properties affect plant cover on a slope. For treatments, we tested natural soil, soil mixed with wood-based growing medium (1:1, w/w), and wood-based growing medium by itself. Physical and chemical characteristics were evaluated after four months from the date of treatment application to the experimental slope site. Soil coverage with seedlings of Lespedeza cyrtobotrya was measured for plant growth evaluation. Physicochemical properties were altered by mixing the natural soil with wood-based growing medium. Particularly, soil moisture and organic matter contents were significantly changed in soils treated with wood-based growing medium compared to soil alone. We confirmed that plant coverage rate was high when wood-based growing medium was mixed with the natural soil. There was a significant linear relationship between moisture content and CEC (Cation Exchange Capacity) of all growth media tested and plant coverage. This result was expected, as moisture content tends to increase with organic matter content, such as in wood-based growing medium. In conclusion, the high moisture content of the wood-based growing medium was considered effective for plant growth in the experimental slope site, and this wood-based growing medium provides a means to improve the harmony between the slope and the surrounding environment.

• Journal of Preventive Medicine and Public Health
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• v.24 no.3 s.35
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• pp.265-278
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• 1991

This study was to examine the effects of insurance coverage on the utilization of public health institutions and to identify the factors associated with the utilization. The data were obtained from household interview surveys conducted twice in Hwachun Gun, Kangwon Do. The time period covered in the first survey was December $17{\sim}31$, 1987, before the implementation of regional medical insurance for the self-employed, and that of the second survey was January 28 $\sim$ Febuary 11, 1990, after its implementation. Major findings emerged from the analysis can be summarized as follows (1) Medical care utilization of rural people markedly increased after they were covered by medical insurance. The insurance coverage increased the utilization of public health institutions as well, and this increase was mainly attributable to the utilization by chronically ill patients. (2) Between 1987 and 1990, the proportion of the utilization of public health institutions over whole medical care utilization decreased. But the proportion increased for chronically ill patients covered by regional medical insurance during the same time span. (3) The results of logistic regression suggested that the rural self-employed utilized public health institutions at an increased rate after they were covered by medical insurance. It was also indicated that the increase resulted from the utilization by chronically ill patients. (4) The relative importance of public health institutions for rural medical care decreased after the implementation of regional medical insurance. But considering that the utilization of public health institutions by chronically ill patients increased after insurance coverage, attention should be directed to improving the capability of public health institutions to control chronic degenerative diseases.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3541-3544
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• 2016

Background: As the treatment modalities for oral cancer have been relatively consistent during the last two-decades, this study was conducted to compare survivals of oral cancer patients in Khon Kaen Province before and after the universal coverage scheme (UC) was launched in Thailand. Materials and Methods: The data were retrieved from the population-based cancer registry of Khon Kaen for oral cancer patients diagnosed during 1992-2001 (pre-UC), and 2004-2012 (post-UC). To compare survival of the two cohorts, Kaplan Meier and log rank tests were employed. Results: Of 1,196 patients, 65% were females and the median age was 65 years. The most common primary sites were lip (31.0%), tongue (29.9%), and buccal mucosa (14.6%). The proportion of early stage cancer increased from 20.4 % in pre-UC to 41.3% in post-UC. The overall 5-year survival rate was 36.5% (95% CI =32.6-40.9) for pre-UC and 32.4% (95% CI = 28.8-36.4) for post-UC. The declining survival was mainly due to an increasing proportion of tongue cancer. However, no survival improvement was demonstrated on subgroup analysis of the tongue cancer patients. Conclusions: After the universal coverage scheme had been launched, early diagnosis increased, but no significant gain in survival for oral cancer patients was achieved.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.1
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• pp.133-144
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• 2018

Objectives Since the health insurance coverage for traditional Korean medicine is very low, some physicians and researcher have suggested that government's institutional support is needed for korean medicine field. Therefore We examine the use of traditional medicine and western medicine in Taiwan, which operates a similar health insurance system to Korea. Methods We selected several studies from Pubmed and NHIRD, that could be used to numerically evaluate the use of traditional medicine. We reviewed the current status of medical use in Taiwan and compare it with that of Korea. Results Through a total of 87 studies, We found that 26.59%~31% of Taiwanese use Traditional medical institutions more than once a year, and the use of traditional medicine has been increasing since 2000. In adults than children, in women than men, the use rate of traditional medicine was high. Especially, herbal medicine was the most common intervention, accounting for 70% of traditional medical care. Conclusions The core of low insurance coverage for traditional Korean medicine is in lack of coverage for herbal medicine. Taiwan's case shows that the unmet demand for traditional Korean medicine of the Korean population can exist widely.