• Journal of Korean Society of Transportation
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• v.17 no.5
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• pp.123-135
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• 1999

The rapid increase of Passenger cars which is caused by the discomfort of Public transit and the Preference of automobiles is the major factor of increasing traffic congestions in Seoul With the point that leading the automobilists to the Public transit can be the most important Policy to ease these traffic congestions, this study focuses on the behavioral aspects of company employees and university students and investigates factors influencing bus ridership. To be brief, by estimating bus ridership through count models, this study investigates factors which influence bus ridership and elicits Political suggestions which lead automobilists to Public transit. The Purpose in this study is the application of appropriate count data model. The count data models have been widely applied to the economic area from the middle of the 1980s and to transportation aspect mainly in the foreign countries from the latter half of the 1980s. Even though a few studies in this country employed count data model to count data. all of them were Poisson regression models without suitable tests for the importance of the model specification. In the end, as the result of statistical test, negative binomial regression model which is suitable for overdispersed data was found to be appropriate for the data of weekly bus ridership. To emphasize the importance of model specification, both of poisson regression model and negative binomial regression model were estimated and the results were compared.

• Journal of the Society of Disaster Information
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• v.17 no.3
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• pp.655-666
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• 2021

Purpose: This study is to develop a method for measuring dynamic speeding risks using vehicle trajectory big data and to demonstrate the feasibility of the devised speeding index. Method: The speed behaviors of vehicles were analysed in microscopic space and time using individual vehicle trajectories, and then the boundary condition of speeding (i.e., boundary speed) was determined from the standpoint of crash risk. A novel index for measuring the risk exposure of speeding was developed in microscopic space and time with the boundary speed. Result: A validation study was conducted with vehicle-GPS trajectory big data and ground-truth vehicle crash data. As a result of the analysis, it turned out that the index of speeding-risk exposure has a strong explanatory power (R²=0.7) for motorway traffic accidents. This directly indicates that speeding behaviors should be analysed at a microscopic spatiotemporal dimension. Conclusion: The spatial and temporal evolution of vehicle velocity is very variable. It is, hence, expected that the method presented in this study could be efficaciously employed to analyse the causal factors of traffic accidents and the crash risk exposure in microscopic space using mobility trajectory data.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.5
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• pp.74-91
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• 2023

Several that analyzed the effectiveness of traffic safety facilities a method of comparing changes in the number of accidents, accident severity, speed through traffic accident data before and after installation or speed data collected from vehicle detection systems (VDS). , when traffic accident data is used, it takes a long time to collect because must be collected for at least one year before and after installation. , the road environment may change during this period, such as the addition of other traffic safety facilities in addition to the facilities to be analyzed. , the location of the VDSs for speed data is often different from the location where analysis is required, and there is a problem in that the investigators are exposed to the risk of traffic accident during on-site investigation. Therefore, this study a case study by establishing a methodology to determine effectiveness video images with a drone, extracting data using a program, and comparing vehicle driving speeds before and after speed reduction facilities. Vehicle speed surveys using drones are much safer than observational surveys conducted on highways and have the advantage of tracking speed changes along the vehicle, it is expected that they will be used for various traffic surveys in the future.

• Journal of Nutrition and Health
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• v.50 no.4
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• pp.391-401
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• 2017

Purpose: The purpose of this study was to estimate the dietary flavonoid intakes of Korean adults according to socioeconomic status. Methods: Using data from the 2007~2012 Korea National Health and Nutrition Examination Survey, a total of 31,112 subjects aged over 19 years were included in this study. We estimated individuals' daily intakes of total flavonoids and seven flavonoid subclasses, including flavonols, flavones, flavanones, flavan-3-ols, anthocyanins, proanthocyanidin, and isoflavones,by linking food consumption data with the flavonoids database for commonly consumed Korean foods. We compared intakes of flavonoids according to the levels of household income and education. Results: Average dietary flavonoid intakes of the study subjects were 321.8 mg/d in men and 308.3 mg/d in women. Daily flavonoid intakes were positively associated with household income level (p < 0.0001) and education level (p < 0.0001). The subjects in the highest household income and highest education level group (OR 0.37, 95% CI 0.30~0.45, p < 0.0001 in men, OR 0.50, 95% CI 0.41~0.60, p < 0.0001 in women) had a lower likelihood of having low total flavonoid intake (less than 25 percentile) compared to the lowest household income and lowest education level group. The food group that contributed to total flavonoid intake with the biggest difference between the lowest and highest groups for both household income level and education level was beverages. Conclusion: This study shows that socioeconomic status was positively associated with flavonoid intake in a representative Korean population. Further research is needed to analyze the association of flavonoid intake with health outcomes according to socioeconomic status such as household income and education level.

• Journal of Korean Library and Information Science Society
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• v.45 no.4
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• pp.277-308
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• 2014

The purposes of this article are to raise the quality issues of Korean academic library collections and explore the feasible solutions to resolve the quality problems. To the end a thorough examination on the quality of Korean academic library collections is at the first hand carried out, and then followed is a careful investigation on the various causes of 'surprisingly low quality' of Korean academic library collections. Finally discussed is the solutions to improve the low quality of library collections at both national and individual academic library level. Discussions on this article are based on the sample data with 10 major academic libraries in South Korea.

• Spatial Information Research
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• v.22 no.2
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• pp.89-97
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• 2014

This study investigated how much the spread of traffic control information affect the traffic congestion in order to identify the behavior of the individual drivers that impacts on the entire transport system. For this purpose, agent-based transportation model was constructed. GIS data were directly used for the transportation model and the processing steps of the simulation results are presented. The results showed that the average speed was not lowered when the traffic information was provided to 30 to 70% of total drivers. In contrast, the driver's average speed is reduced when he traffic information was provided to less than 20% or 80% or more. In summary, the provision of traffic information to drivers has an influence on the traffic flow and bypassing vehicles can generate local congestion. This results can be used as a basis for the future direction of road transport policy.

• Journal of Korea Game Society
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• v.15 no.4
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• pp.121-132
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• 2015

This study suggests a design for an analytical software program and method for multitasking e-sports viewing through the web using an eye tracking device. To fulfill this task, we designed a Window of Interest (WOI) to measure and record visually on a screen wherever numerous multitasking activities occur. In addition, we developed an OBS (Opensource Broadcaster Software) plug-in that records and streams participant viewing behavior patterns in real time. The purpose of this study is as follows. First, unlike existing tools that limit web interface recording to still images, the developed tool can record dynamically via media such as videos. Second, when several windows are processed on a screen, the tool can accurately record the gaze positions of the participants. Lastly, the tool can enhance the objective validity of the data as it can be implemented in natural situations. Therefore, this study can trace natural viewing patterns and behavior as we do not create artificial experimental environments and stimuli.

• Korean Journal of Legislative Studies
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• v.27 no.2
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• pp.5-40
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• 2021

In the 4.7 by-election in 2021, the ruling Democratic Party suffered a record devastating defeat, breaking the trend of a post-intermediate evaluation confirmed in the recent election. Why did the Democratic Party lose by a large margin unlike the recent election trend? In order to find answers to these questions, this study analyzes the voting behavior of individual voters based on the voter consciousness survey data conducted after the 4.7 by-election, while examining the background and causes of such voter choices. As a result of the study, in the 4.7 by-election, as confirmed in previous studies, public opinion against the ruling government was strong, and negative elections were held. However, if we look at the process and results of this by-election in more detail, we can see that it is different from the general by-election. In the past by-elections, the government judgement was due to the passive participation of the ruling party-oriented voters in elections with low political weight, or the active judgement psychology that was maximized in situations where the political burden was less. However, in this by-election, on the contrary, in an election with a high political weight, the active judgement psychology of the Democratic Party and non-partisan voters had an effect on strengthening the midterm evaluation character of the election. In addition, it can be seen that the gathering of conservative voters who support the opposition also had a strong influence on the reinforcement of the midterm evaluation character of the election.

• Journal of Korean Society of Transportation
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• v.27 no.4
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• pp.115-126
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• 2009

The lane-change behavior usually consists of discretionary lane-change and mandatory lane-change types. For the first type, drivers change lanes selectively to maintain their own driving condition and the second type is the case that the drivers must change the current lane, which can occur in recurrent congestion sections like merging and weaving sections. The mandatory lane-change behavior have a great effect on the operation condition of freeway. In this paper, we first generate data such as traffic volumes, speeds, densities, and the number of lane-change within the merging and weaving sections using the data of individual vehicle collected from time-lapse aerial photography. And then, the data is divided into the stable and congested flow by analyzing the speed variation pattern of individual vehicles. In addition, the number of lane-changing from ramp to mainline within every 30-meter interval is investigated before and after traffic congestion at study sites and the distribution of lane-changing at each 30-meter point is analyzed to identify the variation of lane-changing ratio depending on the stable and congested flows. To recognize the effect of mainline flow influenced by ramp flow, this study also analyzes the characteristics of the lane-changing distributions within the lanes of mainline. The purpose of this paper is to present the basic theory to be used in developing a lane-changing model at the merging and weaving sections on freeways.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.2
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• pp.74-88
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• 2020

A Cooperative Intelligent Transportation System (CITS) provides useful information on upcoming hazards in order to prevent vehicle collisions. In addition, the availability of individual vehicle travel information obtained from the CITS infrastructure allows us to identify the level of road safety in real time and based on analysis of the indicators representing the crash potential. This study proposes a methodology to derive road safety content, and presents evaluation results for its applicability in practice, based on simulation experiments. Both jerk and Stopping Distance Index (SDI) were adopted as safety indicators and were further applied to derive road section safety information. Microscopic simulation results with VISSIM show that 5% and 20% samples of jerk and SDI are sufficient to represent road safety characteristics for all vehicles. It is expected that the outcome of this study will be fundamental to developing a novel and valuable system to monitor the level of road safety in real time.