• Journal of Web Engineering
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• v.20 no.8
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• pp.2413-2432
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• 2021

Recently, the demand for high-quality video content has rapidly been increasing, led by the development of network technology and the growth in video streaming platforms. In particular, displays with a high refresh rate, such as 120 Hz, have become popular. However, the visual quality is only enhanced if the video stream is produced at the same high frame rate. For the high quality, conventional videos with a low frame rate should be converted into a high frame rate in real time. This paper introduces a bidirectional intermediate flow estimation method for real-time video frame interpolation. A bidirectional intermediate optical flow is directly estimated to predict an accurate intermediate frame. For real-time processing, multiple frames are interpolated with a single intermediate optical flow and parts of the network are implemented in 16-bit floating-point precision. Perceptual loss is also applied to improve the cognitive performance of the interpolated frames. The experimental results showed a high prediction accuracy of 35.54 dB on the Vimeo90K triplet benchmark dataset. The interpolation speed of 84 fps was achieved for 480p resolution.

• The Journal of Korean Physical Therapy
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• v.9 no.1
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• pp.19-35
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• 1997

Korea will soon experience a high demand for medical rehabilitation specialists, if it tries to deliver advanced health welfare service. In order to medical rehabilitation manpower policies, this study attempts to analyse, estimate and plan a long-term supply for physiatrists, physical therapists, and occupational therapists. The study analysed both national and foreign statistical data of manpower supply for medical rehabilitation specialists. Based on the above data, the demand of and supply for each specialists were estimated for long term up to the year 2030. Based on the comparative analysis results of the future demand and supply. the author intended to develop a new supply plan for the three specialist categories. The major finding of the supply plan are as follows : First, as for the supply plan for physiatrists, the author recommends to adopt the demand estimation 1 as the most suitable. In order to prevent an oversupply of physiatrists, the supply plan 1 is recommended which annual enrollment of specialists will maintain with the quota of fixed number of 63 from the year of 1999. Second, it is estimated that there was already an oversupply of physical therapists in Korea. This oversupply is expected to continue even though there would be an increase in rehabilitation hospital beds, rehabilitation facilities for the elderly, and nursing homes, Thus, it would be desirable to cut down the number of students admitted to physical therapy schools each year. Third, there will be a high demand for occupational therapists in the near future as people become more aware of the usefulness of this therapy. Thus, it is urgent to establish a supply plan to meet the demand. Given the close relationship between physical therapy and occupational therapy, the study recommends that the universities already having the the department of physical therapy open the department of occupational therapy as well.

• Journal of Korean Institute of Industrial Engineers
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• v.27 no.3
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• pp.233-238
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• 2001

This paper deals with demand forecasting of parts in an automobile model which has been extinct. It is important to estimate how much inventory of each part in the extinct model should be stocked because production lines of some parts may be replaced by new ones although there is still demands for the model. Furthermore, in some countries, there is a strong regulation that the automobile manufacturing company should provide customers with auto parts for several years whenever they are requested. The major characteristic of automobile parts demand forecasting is that there exists a close correlation between the number of running cars and the demand of each part. In this sense, the total demand of each part in a year is determined by two factors, the total number of running cars in that year and the failure rate of the part. The total number of running cars in year k can be estimated sequentially by the amount of shipped cars and proportion of discarded cars in years 1, 2,$\cdots$, i. However, it is very difficult to estimate the failure rate of each part because available inter-failure time data is not complete. The failure rate is, therefore, determined so as to minimize the mean squared error between the estimated demand and the observed demand of a part in years 1, 2,$\cdots$, i. In this paper, data obtained from a Korean automobile manufacturing company are used to illustrate our model.

• Environmental and Resource Economics Review
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• v.17 no.3
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• pp.1-29
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• 2008

The goal of this study is to analyze the effects of the second energy tax reform of the transportation sector in Korea. For this purpose, we estimated the elasticities of energy demand(for gasoline, diesel and LPG) by using the ARDL(Auto-Regressive Distributed Lag) Model during the period of 1997 and 2005. We have the empirical results that the demand for diesel would decrease as much as of 382 million barrel per year and the demand for LPG would increase as much as of 20 million barrel per year since 2007. The second energy tax reform would also result in the decrease of 27,346 ton of air pollutants and 0.96 million ton of carbon dioxide per year. This shows that the second energy tax reform would have achieved its own policy goals by reducing energy demand and improving the quality of environment.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.1
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• pp.149-162
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• 2013

Objectives : This study was conducted to estimate the future demand and supply of physicians for korean medicine from 2016 year to 2026 year in order to make an adequate manpower policy in a way of keeping a balance between demand and supply. Methods : Baseline projection method and trend analysis(a polynomial log power equation model) were used in the estimation of future supply and demand respectively. We used data about the amount of oriental doctors from Ministry of Health and Welfare Statistics Yearbook and the treatment days from HIRA Statistics Yearbook. Results : It was projected that the total number of physician of Korean medicine will be 25,178 registered and 18,967 available in clinical setting. According to polynomial equation model which explained the trend of demand and had the highest score of $R^2$ among the equation models, 3,800~5,600 physician in Korean medicine will be oversupplied in 2016 year, 9,000~10,700 physicians in 2021 year and 15,700~17,000 persons in 2026 year depends on annual working days which is 265days, 255days or 239days. Log equation model also showed that overall excess supply of physician manpower in Korean medicine. Conclusions : Alternative manpower policies for Korean medicine doctors should be implemented in a way of both dwindling supplies and growing demand in Korean medical service in terms of Korean medical services utilization and improving physician's productivity.

• International Journal of Highway Engineering
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• v.17 no.3
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• pp.97-105
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• 2015

PURPOSES : The Toll Collection System (TCS) operated by the Korea Expressway Corporation provides accurate traffic counts between tollgates within the expressway network under the closed-type toll collection system. However, although origin-destination (OD) matrices for a travel demand model can be constructed using these traffic counts, these matrices cannot be directly applied because it is technically difficult to determine appropriate passenger car equivalent (PCE) values for the vehicle types used in TCS. Therefore, this study was initiated to systematically determine the appropriate PCE values of TCS vehicle types for the travel demand model. METHODS : To search for the appropriate PCE values of TCS vehicle types, a traffic demand model based on TCS-based OD matrices and the expressway network was developed. Using the traffic demand model and a genetic algorithm, the appropriate PCE values were optimized through an approach that minimizes errors between actual link counts and estimated link volumes. RESULTS : As a result of the optimization, the optimal PCE values of TCS vehicle types 1 and 5 were determined to be 1 and 3.7, respectively. Those of TCS vehicle types 2 through 4 are found in the manual for the preliminary feasibility study. CONCLUSIONS : Based on the given vehicle delay functions and network properties (i.e., speeds and capacities), the travel demand model with the optimized PCE values produced a MAPE value of 37.7%, RMSE value of 17124.14, and correlation coefficient of 0.9506. Conclusively, the optimized PCE values were revealed to produce estimates of expressway link volumes sufficiently close to actual link counts.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.7
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• pp.918-923
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• 2021

The Korean government is developing a 10-year master plan pertaining to the Public Waters Management and Reclamation Act. However, it was observed that implementation of the reclamation project through frequent changes would occupy a significant proportion. Thus, questions are being raised about the effectiveness of the master plan. In view of this, the need for a trend analysis on long-term reclamation demand is growing. Accordingly, in this study, a trend analysis of reclamation demand was carried out using the annual reclamation performance data. The results of the analysis indicate that the demand for reclamation of public waters continued to decline, and the trend has been particularly evident since the 1990s, when it was converted into a reclamation master plan. In addition, the total demand for reclamation during 2021-2030 was calculated to be at a maximum of 13.8 km² and minimum of 1.7 km².

• Journal of Korean Society of Water and Wastewater
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• v.37 no.6
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• pp.363-373
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• 2023

Numerous studies have established a correlation between sociodemographic characteristics and water usage, identifying population as a primary independent variable in mid- to long-term demand forecasting. Recent dramatic sociodemographic changes, including urban concentration-rural depopulation, low birth rates-aging population, and the rise in single-person households, are expected to impact water demand and supply patterns. This underscores the necessity for operational and managerial changes in existing water supply systems. While sociodemographic characteristics are regularly surveyed, the conducted surveys use aggregate units that do not align with the actual system. Consequently, many water demand forecasts have been conducted at the administrative district level without adequately considering the water supply system. This study presents an upward water demand forecasting model that accurately reflects real water facilities and consumers. The model comprises three key steps. Firstly, Statistics Korea's SGIS (Statistical Geological Information System) data was reorganized at the DMA level. Secondly, DMAs were classified using the SOM (Self-Organizing Map) algorithm to consider differences in water facilities and consumer characteristics. Lastly, water demand forecasting employed the PCR (Principal Component Regression) method to address multicollinearity and overfitting issues. The performance evaluation of this model was conducted for DMAs classified as rural areas due to the insufficient number of DMAs. The estimation results indicate that the correlation coefficients exceeded 0.9, and the MAPE remained within approximately 10% for the test dataset. This method is expected to be useful for reorganization plans, such as the expansion and contraction of existing facilities.

• Journal of Korea Water Resources Association
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• v.53 no.12
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• pp.1131-1142
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• 2020

This study assessed evapotranspiration (ET) methods applying for estimation of paddy rice water demand based on agricultural water supply. The Modified Penman (MP) method and the Penman-Monteith (PM) method recently suggested by Rural Development Administration (RDA) were considered. The 6 Korea Rural Community Corporation (KRC) command areas located in Honam province were selected in this study. The climate characteristics were also analysed with the average annual and the growing season temperatures and rainfalls. As a result, the annual average and the growing season temperature showed the increased trend while the rainfall tended to decrease during 30 years. The paddy rice water demand found to be directly influenced by these climate trends as ET also affected by them. The higher values of paddy rice water demand were obtained from applying MP method compared to the one applying PM method. The lower differences were also obtained from MP method for the comparisons between the paddy rice water demand estimated by both methods with agricultural water supply. Therefore, these results suggest that the MP method is more desirable to use for estimating paddy rice water demand in order to achieve stability of irrigation designs and plans.

• The Korean Journal of Emergency Medical Services
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• v.11 no.3
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• pp.65-79
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• 2007

Purpose : It was to find out demand and supply of EMT from 2007 to 2045 and to expand scope of practice of paramedic in Korea. Methods : This study was conducted by applying a projection formula to the data from admission quota for EMT of the Ministry of Education & Human Resources Development, rate of successful candidates of annual report of the National Health Personnel Licensing Examination Board etc. Results : The number of EMTs were 6,043 paramedics, 5,378 EMT-Bs until 2006 and two produce constants derived from simple estimation were paramedic 0.81, EMT-B 0.86. On the American basis of 5.6 EMTs per 10,000, the number of paramedics under the present act will reach the basis around 2015(5.02), the number of paramedics under the amended act will reach the basis around 2030(5.50). Conclusion : There was relationship between scope of practice of paramedic in the act and demand-supply of paramedic, this necessitates surveys, studies, amendment of the act, legalization for expanded scope of practice of paramedic.