• 한국도로학회논문집
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• 제19권1호
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• pp.107-119
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• 2017

PURPOSES : The desire of drivers to increase their driving speeds is increasing in response to the technological advancements in vehicles and roads. Therefore, studies are being conducted to increase the maximum design speed in Korea to 140 km/h. The stopping sight distance (SSD) is an important criterion for acquiring sustained road safety in road design. Moreover, although the perception-reaction time (PRT) is a critical variable in the calculation of the SSD, there are not many current studies on PRT. Prior to increasing the design speed, it is necessary to confirm whether the domestic PRT standard (2.5 s) is applicable to high-speed driving. Thus, in this study, we have investigated the influence of high-speed driving on PRT. METHODS : A driving simulator was used to record the PRT of drivers. A virtual driving map was composed using UC-Win/Road software. Experiments were carried out at speeds of 100, 120, and 140 km/h while assuming the following three driving scenarios according to driver expectation: Expected, Unexpected, and Surprised. Lastly, we analyzed the gaze position of the driver as they drove in the simulated environment using Smarteye. RESULTS : Driving simulator experimental results showed that the PRT of drivers decreased as driving speed increased from 100 km/h to 140 km/h. Furthermore, the gaze position analysis results demonstrated that the decrease in PRT of drivers as the driving speed increased was directly related to their level of concentration. CONCLUSIONS : In the experimental results, 85% of drivers responded within 2.0 s at a driving speed of 140 km/h. Thus, the results obtained here verify that the current domestic standard of 2.5 s can be applied in the highways designated to have 140 km/h maximum speed.

• The Journal of Korean Physical Therapy
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• 제24권6호
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• pp.405-408
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• 2012

Purpose: We examined the effect of dual-task and single-task training on serial reaction time (SRT) task performance to determine whether SRT is based more on motor or perception in a dual-task. Methods: Forty healthy adults were divided into two groups: the dual-task group (mean age, $21.8{\pm}1.6$ years) and the single-task group (mean age, $21.7{\pm}1.6$ years). SRT task was conducted total 480 trial. The four figures were presented randomly 16 times. A unit was set as 1 block that would repeat 10 times. Thus, there were a total of 160 trials for each of the three color conditions. The dual-task group performed an SRT task while detecting the color of a specific shape. The end of the task, subjects answered the specific shape number; the single-task group only performed the SRT task. The study consisted of three parts: pre-measurement, task performance, and post-measurement. Results: Differences of pre and post reaction time between two group was higher for the dual-task group as compared to the single task group and there was a significant interaction between time and group (p<0.05). Conclusion: Our results indicate that. short term period SRT is not quiet effective under dual-task conditions, individuals need additional cognitive processes to successfully navigate a task This suggests that dual-task training might not be appropriate for motor learning enhancement, at least when the training is over a short period.

• 교통기술과정책
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• 제8권6호
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• pp.55-61
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• 2011

• 한국운동역학회지
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• 제20권2호
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• pp.205-212
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• 2010

The purpose of this study was to compare the efficiency of visual perception and impulse according to the three types of Taekwondo players to be able to supply an efficient training method, for this a total of 12 representative Taekwondo players of the Korean National team, 4 poomsae players, 4 kyokpa players and 4 kyorugi players weighting between 68 to 74 kg, and the results from the motion analysis system, eye tracker and Electronic hogu are as follows. For the visual perceptual function, the total body reaction time was slowest for the kyokpa group, and for the visible reaction and vision fixation time was longest of the poomsae group, while the performance movement was fastest for the kyorugi group. As for description of the two kicking motions dollyo chagi and dolgae chagi the longer visual fixation helps the accuracy of the kick. In conclusion, as there was a difference between the groups, this information could help to train the visual perception of players according to what event they are participating in.

• 대한교통학회지
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• 제26권1호
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• pp.181-190
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• 2008

본 연구는 교통약자(어린이와 고령자)에 대한 보행속도 및 인지-반응을 포함한 보행특성에 관한 기초자료를 제공하고, 이와 같은 교통약자의 보행 특성을 반영한 보행 신호시간 모형을 개발하는 목적으로 수행되었다. 본 연구를 위하여 가상횡단보도를 이용한 현장조사를 실시하여 어린이 및 고령자의 보행특성에 관한 자료를 수집하였다. 자료를 분석한 결과 어린이가 고령자에 비해 보행속도가 높게 나타났고, 약 0.63 m/s, 0.57 m/s의 평균속도를 나타내었다. 그러나 인지-반응시간과 여유시간은 고령자가 어린이에 비하여 높게 조사되었다. 이와 같은 특성을 반영한 보행신호시간 산정모형을 개발하여 제시하였다. 개발된 모형에 대한 민감도 분석 결과 실제 보행행태에 적합한 결과를 얻었고, 이를 현재 사용되고 있는 경찰청 모형과 비교한 결과 대부분의 상황에서 현재의 모형보다 증가된 보행 신호시간을 제공하는 것으로 분석되었다. 본 연구결과는 향후 교통약자의 보행환경을 개선하는데 적용할 수 있고, 장기적으로는 교통약자의 이동성 증진에 기여할 것으로 판단된다.

• International Journal of Internet, Broadcasting and Communication
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• 제14권3호
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• pp.230-242
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• 2022

The purpose of this study was to verify the effectiveness of the computerized cognitive rehabilitation program in which areas and to suggest effective ways to utilize the program in the future, being conducted for 20 college students. We lasted this study from May 3 to 23, 2021. As a result of analyzing the groups using the Computer-based Cognitive Rehabilitation Program (CoTras), in terms of the difference in accuracy for the case of visual perception group B was statistically significantly improved than group C(p<0.05). In the case of attention, memory, and orientation, there was no significant difference between groups(p>0.05). In the case of reaction time difference, there was no significant difference between groups in visual perception, concentration, memory, and orientation(p>0.05). And in order to improve attention and visual perception, it is recommended to conduct the program three times with a duration of 20 minutes, and in order to improve orientation and memory, it can be said that it is helpful to conduct one experiment for at least 30 minutes rather than conducting short and frequent experiments. Through this study, we found that it is effective to apply different times according to each area to improve cognitive function. In other words, depending on the purpose of which cognitive function is to be improved, the duration of the program should be applied differently.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1998년도 학술발표회논문집
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• pp.142-146
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• 1998

본 연구에서는 신호등에서 발생하는 Phantom 현상을 관찰하고, 이에 의해 관찰자의 인지반응시간이 변화하는 정도를 측정하였다. Phantom 현상이 발생하면 운전자의 신호등 인지시간이 길어지며, 그 정도는 운전에 장해를 줄 수 있는 정도임을 알 수 있었다. 인지시간의 길이는 점등된 신호등과 소등된 신호등 사이의 휘도 대비에 의해 영향을 받는 것으로 밝혀졌다. 측정 결과를 바탕으로 Phantom 현상을 방지하기 위한 방법들을 제안하였다.

• Journal of Dental Anesthesia and Pain Medicine
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• 제20권5호
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• pp.271-279
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• 2020

Background: The present study aimed to evaluate and compare the efficacy of buffered and unbuffered local anesthesia solutions during inferior alveolar nerve block (IANB) administration in children. Methods: PubMed, Ovid SP, and Cochrane databases were searched separately by two independent reviewers for potential papers published between 1980 and April 2020 using relevant MeSH terms and pre-specified inclusion and exclusion criteria. T Studies of IANB administration in children comparing buffered and unbuffered local anesthesia solutions were evaluated. The primary outcome evaluated was pain (perception and reaction), while the secondary outcome was the onset of anesthesia. Results: A total of five articles were included in a qualitative analysis; among them, four qualified for quantitative analysis of the primary outcome and three for quantitative analysis of the secondary outcome. A fixed-effects model was used to perform the meta-analysis. Pain perception (child-reported pain): Significantly lower pain scores were reported with buffered local anesthesia solution than with unbuffered solution (P = 0.006, MD: -0.32, 95% CI: -0.55 to -0.09). Pain reaction (observer-reported pain reaction in child): No significant difference was found between buffered and unbuffered solution in terms of observer-reported pain behavior in the child (P = 0.09, MD: -0.21, 95% CI: -0.46 to 0.04). Onset of anesthesia: A significantly lower duration of anesthesia onset was reported with buffered local anesthesia solution than with unbuffered solution (P = 0.00001, MD: -12.38, 95% CI: -17.64 to -7.13]. Conclusion: Buffering local anesthesia solution may reduce discomfort due to IANB injection administration and lower the initial onset time of anesthesia. More randomized control trials with adequate sample sizes should be carried out to validate the accuracy of these results.

• 대한교통학회지
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• 제12권1호
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• pp.55-73
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• 1994

The objective of this research is to evaluate the pedestrian signal time involving green and flashing green times. The minimum pedestrian green indication should give time for pedestrian to start crossing safely, and the flashing green indication should give time to complete the crossing. An average pedestrian crossing speed of 1.1(m/s) was estimated by analyzing the field data which was slower than the 1.2(m/s) currently used. Furthermore, the study proposed that design speed for the flashing green time should be slow speed for considerations pedestrian safety, not the average speed. The 0.78-1.01(m/s) of pedestrian speed was estimated at the elementary school areas that indicated 0.2(m/s) slower than the other areas. The pedestrian starting time (perception/reaction time) and time headway from front to back of herd was estimated to determine minimum pedestrian green time. the pedestrian starting time was estimated to determine minimum pedestrian green time. The pedestrian starting time was ranged 2.52-4.29 seconds. The time interval between the pedestrian rows was found to be 1.25-1.86 seconds, which declines as the pedestrian rows increases, The equation to calculate the pedestrian signal, which declines as the pedestrian rows increases. The equation to calculate the pedestrian signal time is proposed using the pedestrian starting time, the time interval between the pedestrian rows, and pedestrian crossing speed given area types (commercial, business, mixed, and elementary school areas), number of both-directional pedestrians for a cycle, crosswalk length and width.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1998년도 춘계학술대회논문집
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• pp.167-172
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• 1998

Methods of evaluating the physiological activity of the living body are EEG, EOG, Heart rate, and Rectal temperature, etc. In the study of Hagiwara and Araki(1993), they found positive correlations among performance test, physiological measurement, and subjective feeling measurement. Human alertness of pilot directly influences on the flight performance that accomplishes a lot of vigilance task and procedure execution in flight. Accordingly, this paper deals with the quantitative and objective performance test based on tracking error and reaction time by means of the new computer test program into which the perception-motion system of human beings is applies. Throughout this experiment using performance thst, the results suggest that performance capability in state of sleep deprivation 2 hours and alcoholic 0.05 .apaprox. 0.06% in blood were more impaired than one in a normal state, and they further showed statistically significant differences between them, which were influenced by impairment factors of body regulation and pilot's grade. We also obtained the prediction value and the 95% confidence interval of tracking error and reaction time at the normal state for the purpose of distinguishing performance capability between the normal state and the abnormal state. And it is ecpected that the evaluation of human alertness using performance test will be applied to the quantitative assessment of an each pilot's realistic consciousness/attention, and will lead a flight commander to the accurate decision of mission approval prior to a flight.