• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.179-187
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• 2009

This study develops a real-time signal control algorithm based on sectional travel times and includes a field test and evaluation. The objective function of the signal control algorithm is the equalization of delay of traffic movements, and the main process is calculating dissolved time of the queue and delay using the sectional travel time and detection time of individual vehicles. Then this algorithm calculates the delay variation and a targeted red time and calculates the length of the cycle and phase. A progression factor from the US HCM was applied as a method to consider the effect of coordinating the delay calculation, and this algorithm uses the average delay and detection time of probe vehicles, which were collected during the accumulated cycle for a stabile signal control. As a result of the field test and evaluation through the application of the traffic signal control algorithm on four consecutive intersections at 400m intervals, reduction of delay and an equalization effect of delay against TOD control were confirmed using the standard deviation of delay by traffic movements. This study was conducted to develop a real-time traffic signal control algorithm based on sectional travel time, using general-purpose traffic information detectors. With the current practice of disseminating ubiquitous technology, the aim of this study was a fundamental change of the traffic signal control method.

• Korean Journal of Radiology
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• v.22 no.7
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• pp.1044-1053
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• 2021

Objective: Motion-corrected averaging with a single-shot technique was introduced for faster acquisition of late-gadolinium-enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging while free-breathing. We aimed to evaluate the image quality (IQ) of free-breathing motion-corrected single-shot LGE (moco-ss-LGE) in patients with hypertrophic cardiomyopathy (HCM). Materials and Methods: Between April and December 2019, 30 patients (23 men; median age, 48.5; interquartile range [IQR], 36.5-61.3) with HCM were prospectively enrolled. Breath-held single-shot LGE (bh-ss-LGE) and free-breathing moco-ss-LGE images were acquired in random order on a 3T MR system. Semi-quantitative IQ scores, contrast-to-noise ratios (CNRs), and quantitative size of myocardial scar were assessed on pairs of bh-ss-LGE and moco-ss-LGE. The mean ± standard deviation of the parameters was obtained. The results were compared using the Wilcoxon signed-rank test. Results: The moco-ss-LGE images had better IQ scores than the bh-ss-LGE images (4.55 ± 0.55 vs. 3.68 ± 0.45, p < 0.001). The CNR of the scar to the remote myocardium (34.46 ± 11.85 vs. 26.13 ± 10.04, p < 0.001), scar to left ventricle (LV) cavity (13.09 ± 7.95 vs. 9.84 ± 6.65, p = 0.030), and LV cavity to remote myocardium (33.12 ± 15.53 vs. 22.69 ± 11.27, p < 0.001) were consistently greater for moco-ss-LGE images than for bh-ss-LGE images. Measurements of scar size did not differ significantly between LGE pairs using the following three different quantification methods: 1) full width at half-maximum method; 23.84 ± 12.88% vs. 24.05 ± 12.81% (p = 0.820), 2) 6-standard deviation method, 15.14 ± 10.78% vs. 15.99 ± 10.99% (p = 0.186), and 3) 3-standard deviation method; 36.51 ± 17.60% vs. 37.50 ± 17.90% (p = 0.785). Conclusion: Motion-corrected averaging may allow for superior IQ and CNRs with free-breathing in single-shot LGE imaging, with a herald of free-breathing moco-ss-LGE as the scar imaging technique of choice for clinical practice.

• The Korean Journal of Health Service Management
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• v.8 no.3
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• pp.13-25
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• 2014

This research was performed to investigate the characteristics and determination factors on tertiary hospital inpatients. The used data was the four waves of Korea Health Panel(2008, 2009, 2010, 2011), and the number of subjects was 4,430 cases of tertiary and general hospital admission. The statistical methodology used in the study is the logistic regression model. The significant affecting factors in utilizing tertiary hospital admission were gender, marital status, education, household income, residence region and ICD-10 classification. Man, graduating college/university, married, high-income were socio-economic affecting factors in tertiary hospital admission. Medical need factor of ICD-10 classification and residence region of inpatients was also significant affecting factors in tertiary hospital admission. The 81.4% of inpatients at tertiary hospital had chronic disease and the 12.9% of inpatients readmitted, the 68.2% had a selecting doctor and the only 26.7% of inpatients reinforced by private medical insurance. This study recommended the Korean government to provide proper rule for tertiary hospital admission in order to improve the equity and efficiency of health care system.

• Korea Journal of Hospital Management
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• v.19 no.3
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• pp.1-10
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• 2014

The purpose of this study was to present base data for an efficient management of medical expenses at the hospital management by doing grasp of status of medical expenses from seamen's insurance by voluntary agreements. A Object of study is analyzing the data of medical expenses occurred from the total number of 2,699(inpatients 507, outpatients 2,192)cases who were covered by seamen's insurance at a general hospital which is located in Pusan Metropolitan City during 48 months from January 1, 2009 to Dec 31, 2012. The main results of this study are as follows: accrual medical expenses are the ship management companies member of P&I insurance is the most highest but share of receivables are the Korean ocean-going companies member of P&I insurance is the most highest, therefore, Korean ocean-going companies focus strictly than the payments from accounts receivable management should be considered to reduce the occurrence and concerning the turn around period of medical receivables are 4 months to 6 months during a research period. Therefore, it will be needed for managers of hospitals to prepare differentiated management based on the characteristics of each in insurer and to have recovery strategies of uncollected medical expenses.

• The Korean Journal of Health Service Management
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• v.9 no.3
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• pp.115-126
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• 2015

Objectives : This research was performed to investigate the characteristics and determination factors of health care policy satisfaction and welfare recognition for health insurance & health care financing. Methods : The utilized data were 4,174 cases who responded to a welfare recognition survey in the 8th wave of the Korea Welfare Panel Study (2013). The statistical methodology used in this study is the multiple regression model. Results : The significant affecting factors of health care policy satisfaction were age, education, household income, welfare attitudes, and health status. Medical utilization & private medical insurance were not related to health care policy satisfaction. The affecting factors of health insurance reinforcement were age, health status, welfare attitudes. The affecting factors of health care financing expansion were age, economic activity type, medical utilization, welfare attitudes. The affecting factors of welfare attitudes were age, economic activity type, household income, health insurance, and health status. Conclusions : Health care policy satisfaction, health insurance reinforcement, and health care financing expansion were all affected by age and welfare attitude; but this was not the case for private health insurance. This study recommended that the Korean government provide active planning for reinforcement of health insurance and publicity of the health care system in order to accord with the prospects of people.

• International Journal of Control, Automation, and Systems
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• v.1 no.1
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• pp.101-110
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• 2003

This paper introduces an identification method for nonlinear models in the form of rule-based Fuzzy-Neural Networks (FNN). In this study, the development of the rule-based fuzzy neural networks focuses on the technologies of Computational Intelligence (CI), namely fuzzy sets, neural networks, and genetic algorithms. The FNN modeling and identification environment realizes parameter identification through synergistic usage of clustering techniques, genetic optimization and a complex search method. We use a HCM (Hard C-Means) clustering algorithm to determine initial apexes of the membership functions of the information granules used in this fuzzy model. The parameters such as apexes of membership functions, learning rates, and momentum coefficients are then adjusted using the identification algorithm of a GA hybrid scheme. The proposed GA hybrid scheme effectively combines the GA with the improved com-plex method to guarantee both global optimization and local convergence. An aggregate objective function (performance index) with a weighting factor is introduced to achieve a sound balance between approximation and generalization of the model. According to the selection and adjustment of the weighting factor of this objective function, we reveal how to design a model having sound approximation and generalization abilities. The proposed model is experimented with using several time series data (gas furnace, sewage treatment process, and NOx emission process data from gas turbine power plants).

• The Korean Journal of Health Service Management
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• v.11 no.3
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• pp.115-127
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• 2017

Objectives : To determine the relationship between of subjective recognition of social class and mental health. Method: The participants were adults with mental health experience over the age of 20 from the Korea Health Panel in 2013 (n=5,126). Methods : Data were analyzed using SPSS Statistics 22.0 The chi-square test and logistic regression analysis used to verify the relationship between subjective recognition of social class and mental health. Results : Lower subjective recognition of social class was associated with experience of depression and suicidal ideation. Other factors associated with depression experience were subjective health status, gender, age, marital status, type of medical care, disability, subjective health status, current smoking and frequency of drinking. Experience of suicidal ideation was, by contrast, associated with subjective health status, age, marital status, economic activity, private insurance, subjective health status and frequency of drinking. Conclusions : Health policies and institutions must be established to optimize health and preventive medicine approaches, especially or mental health as well as the provision of services.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.6
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• pp.3104-3120
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• 2017

The intelligent monitoring system has been successfully applied in many fields such as: monitoring of production lines, transportation, etc. Smart surveillance systems have been developed and proven effective in some specific areas such as monitoring of human activity, traffic, etc. Most of critical application monitoring systems involve object tracking as one of the key steps. However, task of tracking of moving object is not easy. In this paper, the authors propose a method to implement human object tracking in outdoor environment based on human features in shearlet domain. The proposed method uses shearlet transform which combines the human features with context-sensitiveness in order to improve the accuracy of human tracking. The proposed algorithm not only improves the edge accuracy, but also reduces wrong positions of the object between the frames. The authors validated the proposed method by calculating Euclidean distance and Mahalanobis distance values between centre of actual object and centre of tracked object, and it has been found that the proposed method gives better result than the other recent available methods.

• The Korean Journal of Health Service Management
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• v.10 no.3
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• pp.199-211
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• 2016

Objectives : This study compared the influencing factors on life satisfaction after retirement between public pension and specific corporate pension recipients. Methods : This study used the fifth year data of 2013 from the raw data of the Korean Retirement and Income Study collected by the National Pension Research Institute. The data analysis in this study was done with the chi-square test, t-test, and linear regression using SPSS ver. 22.0 to verify the relevance between the general characteristics of pension recipients. Results : This study shows that there was a difference in expenditures and health care costs between public pension and special corporate pension recipients. The influencing factors on life satisfaction for public pension recipients were the level of spending, whether there were limitations in daily life and social activity, whether recipients had financial assets and health care costs while for specific corporate pension recipients, they were education level, level of spending and chronic diseases. Conclusions : A health policy that maximizes life satisfaction and takes into account the type of pencion needs to be considered and implemented.

• The Korean Journal of Health Service Management
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• v.10 no.3
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• pp.159-171
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• 2016

Objectives : This study was performed to investigate the characteristics and ADL(Activities of Daily Living) associated factors of elderly inpatients in long-term care hospitals. Methods : Data were collected from the nationwide data of 'Survey of Patients (2013-2014)' administerd by the Ministry of Health & Welfare. The data included in this study consisted of 27,606 cases of elderly inpatients in long-term care hospitals. Results : The survey scores for the elderly inpatients were as follows: 57.6% 'Needed much and total help' with ADL, followed by 26.6% who 'Needed much help', and 15.8% who 'needed minimal supervision' in long-term care hospitals. The ADL score was high in the following categories: women, old age, referred visit, health insurance type, not-recovered & death, transferred, corporate hospitals, small hospital size, low number of physicians per 100 beds, and high number of nursing staff per 100 beds. The inpatients with 'diseases of the nervous system', 'diseases of the circulatory system' and 'diseases of the genitourinary system' were more likely to have high ADL scores. Conclusions : The results of this study suggest that long-term care hospitals should provide active and proper care for patients with high ADL scores and improve medical personnel training as well provide more medical care.