• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.473-480
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• 2004

Recently, they are interested in the relation between night's vehicle accidents of drivers and the dynamic visual acuity at home and aboard. So, in this research, we tried to design an optical system of the inspection equipment to measure the dynamic visual acuity. A optotype standard did to Landolt's ring with 45mm of diameter and 9mm of gap to maintain the visual acuity of 1.0 in the 30m distance. An optical structure of the inspection equipment was composed of the sequence of an observer, a plus refraction lens system, a minus refraction lens system, and an optotype that was arranged to have characteristics that the size of the first virtual image of the optotype made by the minus refraction lens system grows bigger gradually according to the optotype movement to near distance from far distance, and also the first virtual image moves to the principle plane from the focal point of the plus refraction lens system as the size of the first virtual image arranged to the inside of focal distance of plus refraction lens system grows bigger gradually. As doing these processes, we completed the optical system of which characteristic is that the position of the final second virtual image moves to 3m from 50m as the size of the second virtual image made by the plus refraction lens system maintains to be regular.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.711-718
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• 2013

Traffic pavement markings are one of primary transportation facilities that provide drivers with various road information directly. Thus, a clear understanding of traffic pavement markings is utmost important to improve traffic safety as well as to establish a proper traffic culture. However, no past studies examined drivers' understanding of traffic pavement markings in Korea. Hence, this study investigated drivers' understanding of traffic pavement markings through an elaborated administrated survey, and analyzed the relationship between various drivers' characteristics and understanding regarding pavement marking via cross-classification table and logistic model. The analysis results show that drivers have limited understanding regarding the purpose of the markings. Specifically, the average understanding of pavement markings is 57.41%: the lowest understanding is 25.88% for yield pavement marking, and the highest understanding is 91.18% for advanced pedestrian crosswalk pavement marking. This study also revealed that the understanding of some pavement markings are somewhat influenced by user group such as drivers with suspended or revoked driver licenses, but the overall understanding of pavement markings are not significantly affected by drivers' characteristics such as gender and driving experiences at ${\alpha}$=0.05. Thus, it might be desirable for policy makers to establish pavement marking-related policies for overall drivers rather than specific drivers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.3
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• pp.379-389
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• 2022

The number of public transportation users has dropped drastically due to COVID-19. In this work, my survey was conducted to uncover the factors that influence citizens' travel patterns. Data were collected and logistic regression analysis on the shifts in transportation was undertaken. Additionally, an importance-performance analysis was carried out to investigate how to effectively operate public transportation systems and improve facilities. The main research findings were as follows: First, the more individuals were concerned about COVID-19 (+) and being infected when using public transportation (+), the greater the tendency to switch to private transportation modes. Secondly, when it came to personal traits, respondents who could drive a car (+) or owned a car (+)or did more online shopping (+) or used public transportation for trips (+) tended to switch over, compared with respondents who could not drive or did not own a caror used public transportation to commute. In addition, respondents who were vaccinated (-) or had more household members tended not to switch transportation modes, compared with those who were not vaccinated or had fewer household members. Third, it is important to continue the following efforts to safeguardhygiene linked to public transportation: wearing masks, disinfecting hands, controlling diseases, and general cleaning. The conclusion was that it is important to put traffic congestion and ventilation issues first, especially in regards public transportation, which was not rated as satisfactory enough compared to its importance. The research findings can provide useful basic data when establishing countermeasures to the current COVID-19 circumstances in the areas of public transportation operation and management and in the event of an infectious disease outbreak in the future.

• Journal of the Korean Society of Radiology
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• v.8 no.7
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• pp.467-477
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• 2014

The purpose of this study is to offer data base for establishment of dental training x-ray generator based safety usage through surveying real radiation safety management state of radiation worker's in plan of operations that have dental training x-ray generators and use it. For it, comprehensive references were surveyed referring reports of current state of regulation technique development and domestic radiation safety evaluation and nuclear related legislation regarding radiation safety management of dental training x-ray generators. On the basis of it, questionnaires were filled in about respondent's general characteristic radiation safety manager's status current state of radiation safety management and the level of knowledge & consciousness. For the study, the survey was conducted to 224 people of radiation safety managers and university graduates training assistants and full-time professors who can treat dental training x-ray generators in education center. through this survey 95 questionnaires were used as analysis materials except the insufficient and omitted responses. As a method of analysis, the frequency and percentage were figured out with the general characteristics and safety manager's status. Chi-square test for frequency and correlation per question analysis and Pearson correlation analysis for crosslevel correlation were done with current state of radiation safety management and knowledge & consciousness level. As a result, running dental training x-ray generators was dealt with by 20's to 40's who have high education level over post undergraduate degree and major in dental hygienic. In addition, female have higher consciousness level for radiation safety management than male. It shows significal linear relation statistically(${\chi}^2$ >5, 0.1${\chi}^2$ >5, 0.3${\chi}^2$ >5, 0.3

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.4
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• pp.26-40
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• 2018

The aim of this research is to analyze factors affecting bicycle accidents using the PLS structural equation. Accident types in this study were categorized into total accidents, serious injuries including death, and light injuries which occurred at nationwide Si Gun Gu. It was found that urbanization was the main factor for bicycle accidents through the accident models developed in this study. Population, ratio of economically active population, density of intersections, ratio of urbanized area, commercial and industrial land-uses, number of drive license holders, number of education institutions, number of parks were the main factors causing bicycle accidents. Besides, length of bicycle roads, number of bicycles, and ratio of bicycle as mode choice also increased bicycle accidents.

• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.397-407
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• 2011

The Open Position System is a new personnel management system started in korea, 1999.Open Position System have purpose to use outstanding talents and to expertise from both public and private sector. Korean government adapted open position system in order to use the right man in the right place. And Korean government incresae application of Open Position System. But, in spite of strong good point of Open Position System, We have limitation to apply Open Position System in police organization, generally. Because police have unique characteristics compare with other public organization. There is constant controversy concerning unique characteristics of police organization. Now, Korean police adopt Open Position System in few division: Chiep of Driver's License Agency, Director General for Audit and Inspection of Nation police Agency, Chiep of police hospital. Therefore, this study explore, extention possibility of Open Position System in Korean police.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.3
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• pp.59-73
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• 2021

There are many lives lost due traffic accidents, and which have not decreased despite advances in technology. In order to prevent traffic accidents, it is necessary to accurately forecast how they will change in the future. Until now, traffic accident-frequency forecasting has not been a major research field, but has been analyzed microscopically by traditional methods, mainly based on statistics over a previous period of time. Despite the recent introduction of AI to the traffic accident field, the focus is mainly on forecasting traffic flow. This study converts into time series data the records from 1,339,587 traffic accidents that occurred in Korea from 2014 to 2019, and uses the AI algorithm to forecast the frequency of traffic accidents based on driver's age and time of day. In addition, the forecast values and the actual values were compared and verified based on changes in the traffic environment due to COVID-19. In the future, these research results are expected to lead to improvements in policies that prevent traffic accidents.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.165-176
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• 2022

In order to prevent various accidents with construction machinery, Korea enacted the Construction Machinery Management Act to enhance safety. Until now, there has been a lack of systematic research related to traffic accidents with construction machinery. Therefore, domestic and foreign systems related to construction machinery were reviewed, and the current status was analyzed based on traffic accident data over the past 5 years to derive implications. It is necessary to ensure the safety of construction machinery by correcting institutional loopholes and preparing follow-up measures. In addition, it is necessary to create a separate traffic-safety education program for construction machinery operators to create an environment that can comply with safe road-driving methods and traffic laws.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.6
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• pp.54-67
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• 2013

The main purpose of this study is to analyze the diversion rate by the levels of delay and the types of display. For this study, we developed the logit model by analyzing the result of SP survey of drivers who have driver's licence after manipulating a virtual driving simulator. The result of analysis was that the types of display was not statistically significant to the diversion rate. On the other hand, the levels of delay was very meaningful factor with the diversion rate. When the main road was flowing smoothly, drivers started to detour at the levels of delay 125% under the traffic free flow state. Similarly, when the levels of delay got worse, the diversion rate kept the same percentage as it was at the levels of delay 125% state which represented a smooth road condition. Likewise, when the main road's traffic flow was slow, drivers appeared to make detours at the same state of the levels of delay 125%. It was found that as the levels of delay got worse, the diversion rose higher than the diversion rate at the condition of slow traffic flow situation with the levels of delay 125%. The result of this study suggests the criterion of drivers detour point. For the conclusion, the result of study would be a reasonable reference for establishing transportation strategies by reflecting drivers' detouring property and would improve the efficiency of traffic flow.

• Korean Journal of Social Welfare
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• v.55
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• pp.231-254
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• 2003

The main premise of this study is that the assurance on human rights of the mentally ill is contradictory to 'the greatest happiness of the greatest number' or 'therapeutic benefits'. Accordingly this study aims to find out the conceptual framework of assurance and restriction on human rights of the mentally ill. Using qualitative method, this study conducted the in-depth interview with 10 general public, 9 professionals, 6 mentally ill regarding the several issues of human rights included long-term hospitalization, restriction on driver's licence, involuntary hospitalization, restriction on communication in psychiatric ward. Research results are as follows ; two sets of dimensions are inferred from the analysis of interview transcript. First dimension is the focus of justification, ranging from the emphasis on positive consequences influenced to 'the greatest numbers'(the utilitarian thought) to the emphasis on assurance of rights without any conditions(the deontological thought). Second dimension is the locus of decision, raging from the formal system included the professionals and the government agency to the informal system included the families and the mentally ill. And there are differences in attitudes toward assurance and restriction on rights of the mentally ill among general public, professionals, and the mentally ill. In detail, general public regarded that 'involuntary hospitalization' and 'restriction on driver's license' which are apt to be directly harmful to people must be justified by consequence-centered and decided by the formal system, while 'long-term hospitalization' which is less harmful to people could be justified by right-centered and decided by the formal-system. And they thought that 'restriction of communication' could be justified by right-centered and decided by the informal system. Based on the findings, this study would conclude that practical guidelines for the promotion of human rights of the mentally ill must be developed.