• Radiation Oncology Journal
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• v.16 no.4
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• pp.357-366
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• 1998

Brachytherapy is an essential part of radiotherapy for uterine cervical cancer. The low dose rate (LDR) regimen has been the major technique of intracavitary therapy for cervical cancer. However, there has been an expansion in the last 20 years of high dose rate (HDR) machines using Ir-192 sources. Since 1979, HDR brachytherapy has been used for the treatment of uterine cervical cancer in Korea. The number of institutions employing HDR has been increasing, while the number of low dose rate system has been constant. In 1995, there was a total 27 HDR brachytherapy units installed and 1258 cases of patients with cervical cancer were treated with HDR Most common regimens of HDR brachytherapy are total dose of 30-39 Gy at point A with 10-13 fractions in three fractions per week. 24-32 Gy with 6-8 fractions in two fractions per week, and 30-35 Gy with 6-7 fractions in two fractions per week. The average fractionation regimen of HDR brachytherapy is about 8 fractions of 4.1 Gy each to Point A. In Korea, treatment results for HDR brachytherapy are comparable with the LDR series and appears to be a safe and effective alternative to LDR therapy for the treatment of cervical carcinoma. Studies from the major centers report the five-year survival rate of cervical cancer as. 78-86$\%$ for Stage 1, 68-85$\%$ for stage 11, and 38-56$\%$ for Stage III. World-wide questionnaire study and Japanese questionnaire survey of multiple institutions showed no survival difference in any stages and dose-rate effect ratio (HDR/LDR) was calculated to be 0.54 to 0.58. However the optimum treatment doses and fractionation schemes appropriate to generate clinical results comparable to conventional LDR schemes have yet to be standardized. In conclusion, HDR intracavitary radiotherapy is increasingly practiced in Korea and an effective treatment modality for cervical cancer. To determine the optimum radiotherapy dose and fractionation schedule, a nation-wide prospective study is necessary in Korea. In addition, standardization of HDR application (clinical, computer algorithms, and dosimetric aspects) is necessary.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.9
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• pp.3016-3033
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• 2014

The downlink performance of distributed antenna systems (DAS) with antennas selection is investigated in Rayleigh fading multicell environment, and the corresponding system capacity and bit error rate (BER) analysis are presented. Based on the moment generating function, the probability density function (PDF) and cumulative distribution function (CDF) of the effective signal to interference plus noise ratio (SINR) of the system are first derived, respectively. Then, with the available CDF and PDF, the accurate closed-form expressions of average channel capacity and average BER are further derived for exact performance evaluation. To simplify the expression, a simple closed-form approximate expression of average channel capacity is obtained by means of Taylor series expansion, with the performance results close to the accurate expression. Besides, the system outage capacity is analyzed, and an accurate closed-form expression of outage capacity probability is derived. These theoretical expressions can provide good performance evaluation for DAS downlink. It can be shown by simulation that the theoretical analysis and simulation are consistent, and DAS with antenna selection outperforms that with conventional blanket transmission. Moreover, the system performance can be effectively improved as the number of receive antennas increases.

• Journal of Korean Neurosurgical Society
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• v.56 no.3
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• pp.248-253
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• 2014

Objective : Cortical dysplasia (CD) is one of the common causes of epilepsy surgery. However, surgical outcome still remains poor, especially with frontal lobe epilepsy (FLE), despite the advancement of neuroimaging techniques and expansion of surgical indications. The aim of this study was to focus on surgical strategies in terms of extent of resection to improve surgical outcome in the cases of FLE with CD. Methods : A total of 11 patients of FLE were selected among 67 patients who were proven pathologically as CD, out of a total of 726 epilepsy surgery series since 1992. This study categorized surgical groups into three according to the extent of resection : 1) focal corticectomy, 2) regional corticectomy, and 3) partial functional lobectomy, based on the preoperative evaluation, in particular, ictal scalp EEG onset and/or intracranial recordings, and the lesions in high-resolution MRI. Surgical outcome was assessed following Engel's classification system. Results : Focal corticectomy was performed in 5 patients and regional corticectomy in another set of 5 patients. Only 1 patient underwent partial functional lobectomy. Types I and II CD were detected with the same frequency (45.45% each) and postoperative outcome was fully satisfactory (91%). Conclusion : The strategy of epilepsy surgery is to focus on the different characteristics of each individual, considering the extent of real resection, which is based on the focal ictal onset consistent with neuroimaging, especially in the practical point of view of neurosurgery.

• Journal of the Korean GEO-environmental Society
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• v.14 no.4
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• pp.29-37
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• 2013

In order to recycle both water sludge and waste fishing net(WFN), it was investigated in this paper the engineering characteristics of mixtures that consisted of different content of water sludge(0%, 10%, 30%, 50%) and reinforced with waste fishing net(unreinforced, untreated WFN, glue treated WFN). WFN or glue treated WFN(1&2 layers) was also added to the mixture to improve the interlocking between the soil particle and WFN. Several series of laboratory tests such as compaction test, triaxial test, oedometer test, permeability test and leaching test were carried out. The experimental test results indicated that, as water sludge content increases, maximum dry unit weight, cohesion, friction angle, and permeability of the mixture decrease, while optimum moisture content, compression index, expansion index and compressibility increase. For the case of reinforced mixture, its cohesion and friction angle are increased due to the inclusion of WFN and glue treated WFN. Leaching result of mixture was satisfied with standard of ministry of environment.

• Korean Journal of Remote Sensing
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• v.11 no.3
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• pp.71-81
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• 1995

The purpose of this research were to find ways to detect ecotone between the Mt. Pukhansan National Park and adjacent urban residential areas, to measure the width and size of ecotone around the park, and to investigate temporal change of ecotone around the Park. Normalized Difference Vegetation Index(NDVI) derived from TM data (May of 1985, 1987, and 1993) and the analytical capabilities of GIS were used to investigate the impacts of human activities inside of and outside of the boundary of the park. Major findings of the study can be summarized as follows: First, ecotone around the boundary of the national park could be identified from NDVI-distance curves derived by a series of buffering operations with a GIS. Second, average width of ecotone around the park was nealy doubled during 1985-1993 period. Third, NDVI vaules of the park were about 14 percent higher than those of surrounding areas. Finally, it seems that the expansion of the ecotone of the park is related to heavy trampling of visitors and various types of environmental pollution of the adjacent urban areas.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.5
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• pp.113-129
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• 2021

Recently, traffic congestion in the city is continuously increasing due to the expansion of the living area centered in the metropolitan area and the concentration of population in large cities. New road construction has become impossible due to the increase in land prices in downtown areas and limited sites, and the importance of efficient data-based road operation is increasingly emerging. For efficient road operation, it is essential to classify appropriate scenarios according to changes in traffic conditions and to operate optimal signals for each scenario. In this study, the Dynamic Time Warping model for cluster analysis of time series data was applied to traffic volume and speed data collected at continuous intersections for optimal scenario classification. We propose a methodology for composing an optimal signal operation scenario by analyzing the characteristics of the scenarios for each data used for classification.

• Health Policy and Management
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• v.31 no.3
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• pp.344-354
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• 2021

Background: The purpose of this study was to analyze the effect of national health insurance coverage of Chuna therapy in April 2019 on the costs and service uses in automobile insurance. Methods: This study used the claim data from Health Insurance Review and Assessment Service. A total of 189,912 inpatients and 1,550,497 outpatients who received Chuna therapy covered by automobile insurance in oriental medical institutions were included. The analysis period was from July 2018 to December 2019, and a total of 18 months before and after April 2019, when Chuna therapy was covered by national health insurance. Interrupted time series analysis was applied to analyze the impact on the costs and service uses of Chuna therapy in automobile insurance before and after April 2019. Results: From July 2018 to December 2019, for 189,912 inpatients the cost and the number of times for Chuna therapy per capita were increased by 22.0% and decreased by 7.3% respectively right after the implementation of the policy. In the case of 1,550,497 outpatients, the cost of Chuna therapy per capita tends to be increased by 0.4% in overall study periods and increased 28.4% immediately after the implementation of the policy. Meanwhile, the number of times and visits for Chuna therapy per capita tends to be increased by 0.4% in overall study periods but decreased by 0.4% after the implementation of the policy. Conclusion: Results suggest that if the national health insurance coverage of oriental medicine services increases according to the policy stance for benefit expansion in national health insurance, the criteria for providing national health insurance benefits should be considered with the comprehensive impacts on the costs and service uses of automobile insurance.

• Journal of Climate Change Research
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• v.6 no.3
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• pp.223-231
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• 2015

Although a considerable part of climate change can be explained by temperature change, hydrological change such as precipitation, evapotranspiration, and runoff impact more on society. For the ascertain a hydrological change in agriculture sector, this study estimate evapotranspiration of cropland in the Korean peninsula, and then to assess the drought severity in the past 30 years through the estimated potential evapotranspiration and observed precipitation. The potential evapotranspiration is estimated by EPIC model and Penman-Monteith method and the drought severity in cropland of the Korean peninsula is assessed using Normalized Precipitation Evapotranspiration Index (NPEI) based on the difference in precipitation and potential evapotranspiration. In North Korea, the estimated evapotranspiration tends to increase even though a significant change is not found due to the change of climate. Although a time series change in drought severity in the past 30 years is not pronounced, a deviation by year and difference between South and North Korea is certain. One reason of this is difference in precipitation and evapotranspiration change according to the latitude. The result including expansion of facilities for water management in North Korea can be used for agricultural decision making, as well as base data of climate change adaptation.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.751-761
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• 2021

The Vietnamese economy is a developing country that has brought many opportunities and challenges for the banking system. Commercial banks have developed strongly from quality to quantity, which plays a vital role in developing the economy. They play an important role in capital formation, which is essential for the economic development of a country. They provide financial services to the general public and businesses, ensuring economic and social stability and sustainable growth of the economy. Therefore, the relationship between bank depth and economic growth is of importance in research. This paper used a VAR (Vector Autoregressive Models) estimator for time series data models. The data is collected quarterly from the first quarter of the year 2000 to 2020. The study uses the VAR model to examine the causal relationships of economic growth, growth in money supply expansion, private sector capital requirement, and banks' domestic credit. The results indicate a general short-run relationship between banking sector depth and economic growth with a positive connection, but in the long term, the relationship between these variables can be reversed because of other macro factors. The findings show the two-way causal relationship between GDP growth and banking depth factors. This research contributes to policy-making by underlining the banking sector depth determinants when setting regulations and policies to develop the banking sector.

• The Journal of Bigdata
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• v.5 no.2
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• pp.111-120
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• 2020

Despite the recent economic contraction caused by the Corona 19 incident, interest in the residential environment is growing as more people live at home due to the increase in telecommuting, thereby increasing demand for remodeling. In addition, the government's real estate policy is also expected to have a visible impact on the sales of the interior and furniture industries as it shifts from regulatory policy to the expansion of housing supply. Accurate demand forecasting is a problem directly related to inventory management, and a good demand forecast can reduce logistics and inventory costs due to overproduction by eliminating the need to have unnecessary inventory. However, it is a difficult problem to predict accurate demand because external factors such as constantly changing economic trends, market trends, and social issues must be taken into account. In this study, LSTM model and 1D-CNN model were compared and analyzed by artificial intelligence-based time series analysis method to produce reliable results for manufacturers producing furniture components.