• Journal of the Korean Society of Safety
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• v.21 no.5 s.77
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• pp.103-111
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• 2006

The purpose of this study was to analyse the relationships between cognitive abilities and driving characteristics of elderly drivers. Driving characteristics of elderly and younger drivers who were driving a fixed base driving simulator vehicle were examined. Participants consisted of 12 drivers over age 65 (the 'older' group) and 12 drivers between the ages of 25 and 55 (the "younger" group). As indices of cognitive ability, critical flicker fusion frequency (CFF) tests and cognitive reaction tests were given before the driving task. CFF was also tested after the simulated driving task for both groups. Cognitive reaction tests, which were composed of speed estimation tests, multiple choice reaction tests and obstacle avoidance tests, were developed by the Korean Road Traffic Safety Authority in 2003. CFF values between the two groups exhibited significant differences both before and after the task, with a p-value less than 0.01 and a t-value of -3.01 before the test and a p-value less than 0.031 and a t-value of -2.35 after the test. Older drivers' CFF values were lower than those of the younger. However, there was no difference in older or younger driver CFF values before and after the task within the same group. Except for the multiple choice reaction test, there was no difference in cognitive reaction test results between the two groups. The elderly drivers made more errors though they did not differ from the younger drivers in reaction times. At the simulated driving task the reaction time of the elderly driver was longer than that of the younger; however, the driving speed of the elderly was lower and the number of collisions greater. There was a positive correlation (r=.496) between the number of errors in the multiple choice reaction test and the number of collisions in the driving task. Therefore, it was identified that critical attributes contributing to automobile crashes involving elderly drivers included cognitive difficulty in judging and responding to complex situations.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.43 no.6
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• pp.401-406
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• 2017

Objectives: Headache is the most common complaint of patients suffering from temporomandibular joint disorders (TMDs). Thus, temporomandibular joint (TMJ) examinations maybe necessary in patients with headache. Considering the high prevalence of bruxism and TMDs in patients with headache the effects of conservative TMD treatment on headache should be assessed. Materials and Methods: Patients were questioned about headaches in the past three months. Those responding affirmatively to this question were examined for TMD and bruxism. After the examinations, 219 patients remained in the study and received self-management instructions. Patients were requested to modify oral habits except when eating or sleeping. The degree of pain (visual analogue scale), headache disability index (HDI), frequency of headaches (FH) per month and TMD intensity were evaluated. Results: The median levels of pain, HDI, FH, and TMD intensity were 8, 44, 8, and 7, respectively, before modifying oral habits and decreased to 4, 24, 2, and 3, respectively, after intervention. These decreases were statistically significant. Conclusion: Having patients maintain free space between the teeth and relax muscles can be an efficient method to treat headache and TMD, especially when repeated frequently.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.12
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• pp.624-630
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• 2001

The trend of the regulations on environmental issues are getting tight. Responding to this trend new technologies such as moving electrodes, wide pitch and pulsed power supply are also introduced in the electrostatic precipitator(EP) systems. The introduction of wide pitch and moving electrodes enhances the system performance of the EPs by improving air-flow and by improving the ash reentrainment on rapping. The power supplies for the EPs developed up to date include thyristor-based dc or intermittent type, SMPS(switching mode power supply) type and the pulsed-power supply type. The use of the pulsed ones is known to improve dust-collecting efficiency of high resistivity ash and reduces back corona occurrence in the collecting plate. There are two kinds of pulsed-power supplies; one with pulsed transformers and the other with direct dc switching devices. The latter uses rotary spark gap switches or semiconductor switches. Both have the merits and demerits: the spark gap switches are simple and robust but has short life time, hence, high maintenance cost, whereas the semiconductor switches have long life time but are costly. In this study, A high voltage power supply with superimposing voltage pulse on dc source was developed for EPs. This study describes circuit topology, operating principle of the scheme, and analysis of experimental results on Dong-Hae Power Plant. The pulsed power supply consists of a variable dc power supply with ratings of 60kV, 800mA and pulse generator which is made of high voltage thyristor-diode switch strings, an LC resonant tank and a blocking inductor. The pulse generator generates variable pulse-voltage up to 70kV using a high frequency resonant inverter with a variable dc source. Two prototypes were built and tested on 250MW DongHae power plant to verify the possibility of the commercial use and the normal operation in the transient states.

• Journal of Environmental Science International
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• v.29 no.7
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• pp.773-784
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• 2020

In order to protect the lives and property of citizens, the central and local governments are responding by enacting municipal ordinances and regulations as the frequency of extreme weather conditions due to climate change increases and intensity increases gradually. Accordingly, the basic contents and strategies of domestic and foreign policies to cope with cold and heat waves were reviewed, referring to measures suitable for application to the Daegu metropolitan area. In addition, it is intended to provide a policy alternative to Daegu metropolitan area to minimize damage from extreme weather by identifying the current status, characteristics, and future prospects of extreme weather in Daegu metropolitan area. Since the damage caused by the cold wave in Daegu area is not as great as that of other regions, it is urgent to come up with cold wave measures for the health and transportation sectors, and to come up with measures against the heat wave as the damage caused by the heat wave is the most serious in the country. Also we will identify spatial characteristics so that the districts and counties with high vulnerability to extreme weather can be identified and implemented first, and present civic life-oriented facilities and civic action guidelines to overcome cold and heat waves.

• Science of Emotion and Sensibility
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• v.8 no.4
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• pp.403-413
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• 2005

The purpose of the present study was to investigate the responses to positive/negative emotional stimuli for the different sensitivities of behavioral activation system (BAS) and behavioral inhibition system (BIS). We recorded If-channel EEG data for 8 BAS sensitive subjects an48 BIS sensitive subjects. EEGs were analyzed with LORETA (Low-resolution electromagnetic tomography) From scalp-recorded electrical potential distribution, LORETA computes the three-dimensional intracerebral distributions of current density for specified EEG frequency bands. hs results , significant differences between the BAS sensitive group ant the BIS sensitive group appeared LORETA alpha activities over the prefrontal lobe and the cingulate gyrus. Prefrontal regions and limbic system including cingulate gyrus are involved in emotional processing. Moreover, subjects with the high BAS sensitivity. responded more sensitively to the positive stimulation than subjects with the high BIS sensitivity. Therefore, our results suggest the possibility of correlation between BAS/BIS sensitivity and positive/negative emotional stimuli.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.7
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• pp.1634-1642
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• 2014

Mobile RFID system, that consists of the existing RFID reader mounted on the mobile devices such as smartphones, is able to provide the users a variety of services and convenience. But security of mobile RFID system is too weak like the existing RFID system. In this paper, the mobile RFID mutual authentication protocol with high level of security is proposed to overcome the troubles such as cryptographic protocols in the existing RFID system responding with the same value in every authentication procedure and the exposure in the exchange of messages. The proposed protocol exchanges messages unexposed by using the random numbers generated in the mutual authentication between the tag and the reader and making numbers coded with the symmetric key. Besides, the protocol uses the mutual authentication utilizing OTP by considering the characteristics of the reader embedded in mobile devices in the mutual authentication process between the reader and the server. Because changed message in every authentication, which produces safe from spoofing attacks and replay attacks, etc.

• Journal of Environmental Science International
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• v.27 no.11
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• pp.957-966
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• 2018

This study intend to induce citizen's voluntary preliminary disaster prevention activity to reduce damage of typhoon that occurs every year. For this purpose, a survey was conducted to develop Typhoon information contents. The number of samples used in the survey was set to 500 people, and citizens living in Jeju, Busan, and Jeonlanam-do were surveyed for areas with high typhoon disasters in order to develop practical and efficient information. The survey consisted of perception about natural disaster, how to get and use weather information, satisfaction with typhoon information and requirements. The general public perceived the typhoon as the first natural disaster. As a result of responding to the method of obtaining and utilizing weather information, the frequency of collecting weather information at the time of issuance of typhoon special report is higher than usual. The purpose of using weather information is clear and the response rate is high for the purpose of disaster prevention. The medium mainly collecting weather information is Internet portal site and mobile phone besides television. The current satisfaction with typhoon weather information is 34.8%, in addition to the accuracy of prediction, it is necessary to improve the information (that is content) provided. Specific responses to the content were investigated not only for single meteorological factors, but also for possible damage and potential countermeasures in the event of a disaster such as a typhoon. As can be seen from the above results, people are requested to provide information that can be used to detect and cope with disasters. The development of new content using easy accessible media will contribute to the reduction of damages caused by the typhoon that will occur in the future, and also to the disaster prevention activity.

• Journal of the Korea Safety Management & Science
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• v.24 no.4
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• pp.85-93
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• 2022

Today's customer service providers, who have the greatest impact on customer satisfaction, are experiencing severe stress and job burnout due to various causes. Unlike general companies, the corporation has a relatively high level of dissatisfaction with customer service since there is a large conflict between the provision of kindness and the reasonable handling of civil complaints according to laws and regulations. In order to analyze the environment of the NPS' customer service providers, 5.583 branch employees working at the National Pension Service and 407 call center employees were surveyed online using the questionnaire function of the Enterprise resource planning system. The contents of the survey consisted of a survey on customer-facing employees, the level of awareness of customer-facing workers protection measures, and opinions on improvement and supplementation related to customer-facing workers protection measures. As a result of the survey, 72.8% of the total respondents experienced grievance complaints, and the proportion of call center employees was even higher at 89.0%. In addition, both the branch and the call center had the largest share of complaints about obstruction of business, unreasonable demands, abusive language, and verbal abuse. More than 40% of call center employees in their 20s and 30s experienced the highest frequency of complaints 13 or more times a year. The most difficult thing in the process of responding to complaints was that both branch offices and call centers had insufficient psychological recovery time, lack of space, and lack of help from colleagues and superiors. Based on the survey analysis, it is suggested to establish a countermeasure through case analysis rather than the right to suspend work for civil complaints that cannot be handled, such as customized manuals and action strategies for the age group with high grievance complaints.

• Korean Journal of Community Nutrition
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• v.28 no.2
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• pp.124-140
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• 2023

Objectives: This study examined the changes in dietary habits, the prevalence of chronic diseases, and mental health problems in the regional areas of the Republic of Korea before and after the COVID-19 pandemic to provide evidence of the status of regional health inequalities. Methods: This study analyzed Korean adults aged 19 or older who participated in the Korea Community Health Survey (n = 686,708) and Consumer Behavior Survey for Foods (n = 19,109) from 2018 to 2020. The participants were classified according to their residence area (Seoul metropolitan area, Metropolitan cities, Provinces); 2018-2019 were defined as before COVID-19, and 2020 as after COVID-19. The dietary behaviors, chronic diseases, and mental health problems were measured using a self-report questionnaire. Results: After COVID-19, the eating-out usage rate in the Seoul metropolitan area and Provinces decreased compared to before COVID-19 (P < 0.001), and when responding that they eat out, the frequency of eating out with household members in the Seoul metropolitan area increased (P = 0.024). The deliveries/takeout usage rate in the Provinces decreased after COVID-19 compared to before (P < 0.001). After COVID-19, the prevalence of obesity decreased in all regions (P < 0.001), and the prevalence of hypertension increased significantly in the Provinces (P = 0.015). The prevalence of diabetes mellitus increased continuously before and after COVID-19 in all regions (P < 0.002). High-risk subjective stress levels increased significantly in the Seoul metropolitan area (P < 0.001), and sleep duration significantly increased in all regions (P < 0.001). Major depressive disorder was reduced significantly in Metropolitan cities (P = 0.042) and Provinces (P < 0.001). Conclusions: After the COVID-19 pandemic, the prevalence of chronic diseases and mental health problems showed regional differences along with changes in dietary habits. It is necessary to reflect the regional differences in dietary habits in future policies resolving regional health inequalities.

• The Journal of Korean Medicine
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• v.44 no.2
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• pp.45-59
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• 2023

Objectives: This study investigated the role of Korean medicine doctors in the national quarantine system and the status of their duties through questionnaire surveys and in-depth interviews with Korean medicine staff who participated in COVID-19 work. Methods: We developed a questionnaire survey to investigate the status and perception of Korean medicine doctors' participation in responding to infectious diseases, and the results were derived by conducting frequency analysis and T-test using SPSS program. The measurement variables of this study were the status of COVID-19 related work participation and perception of Korean medicine doctors' role in infectious diseases, and the maximum significance level was 0.05. Results: There were 300 respondents to the survey, and as for the COVID-19 related work, Korean medicine treatment for COVID-19 patients accounted for the most(52.7%), and various preventive and treatment tasks such as epidemiological investigations and specimen collection were conducted. Conclusion: According to this study, it was confirmed that there are sufficient legal and administrative grounds for Korean medicine doctors to perform specimen collection and epidemiological investigations. Therefore, it is necessary to prepare a policy framework to solidify the status of Korean medicine doctors in national infectious diseases in the future.