• Journal of ILASS-Korea
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• v.24 no.2
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• pp.73-81
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• 2019

It is expected that the introduction of real-driving emission will strengthen the exhaust emission. However, various researches have been reported that real-driving emission has been influenced by factors such as characteristics of the test routes and driving characteristics for drivers. In order to reflect this effect, European Commission applied the concept of driving dynamics to prevent deliberately driving of excessive and acceleration over RDE test. The purpose of this study is to analyze the characteristics of exhaust emissions according to real-driving test in three test routes and driving style. As a result of the test, it was confirmed that when the same driver tested real-driving test under three test routes, it depends on the driving characteristics of the route. Also, RDE-NOx for driving style was that severe driving has been about 16 times higher than normal driving in KNUT route.

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.107-122
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• 2015

PURPOSES : The use of virtual driving tests to determine actual road driving behavior is increasing. However, the results indicate a gap between real and virtual driving under same road conditions road based on ergonomic factors, such as anxiety and speed. In the future, the use of virtual driving tests is expected to increase. For this reason, the purpose of this study is to analyze the gap between real and virtual driving on same road conditions and to use a calibration formula to allow for higher reliability of virtual driving tests. METHODS : An intelligent driving recorder was used to capture real driving. A driving simulator was used to record virtual driving. Additionally, a virtual driving map was made with the UC-Win/Road software. We gathered data including geometric structure information, driving information, driver information, and road operation information for real driving and virtual driving on the same road conditions. In this study we investigated a range of gaps, driving speeds, and lateral positions, and introduced a calibration formula to the virtual record to achieve the same record as the real driving situation by applying the effects of the main causes of discrepancy between the two (driving speed and lateral position) using a linear regression model. RESULTS: In the virtual driving test, driving speed and lateral position were determined to be higher and bigger than in the real Driving test, respectively. Additionally, the virtual driving test reduces the concentration, anxiety, and reality when compared to the real driving test. The formula includes four variables to produce the calibration: tangent driving speed, curve driving speed, tangent lateral position, and curve lateral position. However, the tangent lateral position was excluded because it was not statistically significant. CONCLUSIONS: The results of analyzing the formula from MPB (mean prediction bias), MAD (mean absolute deviation) is after applying the formula to the virtual driving test, similar to the real driving test so that the formula works. Because this study was conducted on a national, two-way road, the road speed limit was 80 km/h, and the lane width was 3.0-3.5 m. It works in the same condition road restrictively.

• Journal of Auto-vehicle Safety Association
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• v.15 no.1
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• pp.16-26
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• 2023

Recently, the importance of simulation in a virtual driving environment as well as real road-based tests for autonomous vehicle testing is increasing. Real road tests are being actively conducted at K-City, an autonomous driving test bed located at the Korea Automobile Safety Test & Research Institute of the Transportation Safety Authority. In addition, the need to advance the K-City virtual driving environment and build a virtual environment similar to the autonomous driving system test environment in real road tests is increasing. In this study, for K-City of Korea Automobile Safety Test & Research Institute, using detailed drawings and actual field data, K-City virtual driving environment was advanced, and similarity verification was verified through comparative analysis with actual K-City.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.1
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• pp.56-62
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• 2017

Although most electricity production contributes to air pollution, the vehicle organizations and environmental agency categorizes all EVs as zero-emission vehicles because they produce no direct exhaust or emissions. Currently available EVs have a shorter range per charge than most conventional vehicles have per tank of gas. EVs manufacturers typically target a range of 160 km over on a fully charged battery. The energy efficiency and driving range of EVs varies substantially based on driving conditions and driving habits. Extreme outside temperatures tend to reduce range, because more energy must be used to heat or cool the cabin. High driving speeds reduce range because of the energy required to overcome increased drag. Compared with gradual acceleration, rapid acceleration reduces range. Additional devices significant inclines also reduces range. Based on these driving modes and climate conditions, this paper discusses the performance characteristics of EVs on energy efficiency and driving range. Test vehicles were divided by low / high-speed EVs. The difference of test vehicles are on the vehicle speed and size. Low-speed EVs is a denomination for battery EVs that are legally limited to roads with posted speed limits as high as 72 km/h depending on the particular laws, usually are built to have a top speed of 60 km/h, and have a maximum loaded weight of 1,400 kg. Each vehicle test was performed according to the driving modes and test temperature ($-25^{\circ}C{\sim}35^{\circ}C$). It has a great influence on fuel efficiency amd driving distance according to test temperature conditions.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.1
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• pp.141-158
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• 2022

Currently, there are some aptitude test systems for older drivers in Korea. However, there are no methods and systems to evaluate the real driving ability for older drivers based on filed driving test. This study was conducted to investigate the availability to use the driving course test used for driving license for identifying difference in driving ability of older and non-older drivers. For the research purpose, filed experiments were conducted using the real driving course test site and evaluation times used in the field. In particular, driving behavior data that obtained from the experiments for two driver groups, older and non-older drivers, were analyzed and compared. From several statistical analyses of driving ability and vision and cognitive ability, it was found that the currently used driving course test site and evaluation times were not appropriated to identify driving ability deficiency of older drivers. To solve the problem, this study developed five evaluation items to identify driving ability deficiency of older drivers using the currently used driving course test site. It was also found that the developed five evaluation items have statistically significant correlation with vision and cognitive ability.

• Korean Journal of Occupational Therapy
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• v.26 no.4
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• pp.127-143
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• 2018

Objective : The purpose of this study was to compare with the effects of driving simulator and Dynavision training after stroke through the test of cognitive ability and driving performance. Methods : Twenty-one stroke patients were randomly classified to the driving simulator training group (N=11) and Dynavision training group (N=10), and were carried out respectively training for 15 times. The driving performances was measured by the driving simulator test, and cognitive-perceptive abilities was measured by the DriveABLE Cognitive Assessment Tool, Trail Making Test-A, Trail Making Test-B and Mini Mental State Examination-K. Results : The driving simulator training group showed significant changes in all cognitive tests and most of driving performances. The Dynavision training group also showed significant changes in all cognitive tests except for Trail Making Test-A and some driving performances. The significant differences on both groups were found regarding the estimated degree of results on the on-road evaluation, the number of off road accidents and collisions. In addition, the causal influence of the two training methods on these variables was analyzed to be more than 20%. Conclusion : The driving simulator and Dynavision training were found to be effective intervention in the driving rehabilitation after stroke. In particular, it was confirmed that the driving simulator is an effective training to improve overall driving ability of stroke patients. In addition, the difference in training effect between the two training methods was found to be more than 20%.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.4
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• pp.372-377
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• 2015

In this paper, the consideration factors that affect the actual driving of a rover wheel was examined based on the wheel-terrain model. For the evaluation of driving performance in a real environment, the test bed of the rover wheel consists of the driving part of the wheel and sensing part of the various parameters was designed and assembled. Using the test bed, the preliminary driving experiment concerning the slip ratio, sinkage, and friction force according to the rotational velocity and the shape of the wheel were carried out and evaluated. The wheel test bed and the experiment results are expected to contribute to finding the optimal result in the designing of the wheel shape and the planning of the driving conditions through further study.

• 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.

• International Journal of Highway Engineering
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• v.19 no.6
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• pp.139-145
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• 2017

PURPOSES : This study analyzed the difference in a driver's workload between using a driving simulator and field driving in tunnel, highway. METHODS : Based on the literature review, it was found that a driver's workload could be quantified using biosignals. This study analyzed the biosignal data of 30 participants using data collected while they were using a driving simulator and during a field test involving tunnel driving. Relative energy parameter was used for biosignal analysis. RESULTS : The driver's workload was different between the driving simulator and field driving in tunnels, highway. Compared with the driving simulator test, the driver's workload exhibited high value in field driving. This result was significant at the 0.05 level. The same result was observed before the tunnel entrance section and 200 m after the entrance section. CONCLUSIONS : This study demonstrates the driving simulator effect that drivers feel safer and more comfortable using a driving simulator than during a field test. Future studies should be designed considering the result of this study, age, type of simulator, study site and so on.

• Therapeutic Science for Rehabilitation
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• v.9 no.1
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• pp.45-55
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• 2020

Objective : The purpose of this study was to investigate the effects of visual perception on driving performance and the importance of visual training for improving driving performance in patients with stroke. Methods : The evaluations, using MVPT(Motor-free Visual Perception Test), TMT A&B(Trail Making Test A & B), UFOV(Useful Field Of View test), and a driving simulator, were carried out with patients in department of physical medicine and rehabilitation in a rehabilitation hospital from October 2014 to November 2014. Results : Driving performance was related to the ability of various visual perceptions of patients with stroke, and the highest correlation was found in the UFOV subtest 2, TMT B, and MVPT. The results of discriminant analysis indicated a sensitivity of 100.0%, specificity of 80.0%, and predicted the results of the driving simulator with 89.5% accuracy. Conclusion : This study found that visual-perception skills influence driving performance and suggested the importance of visual-perception skill training for driving.