PURPOSES : The purpose of this study is to identify the causes and expected problems of traffic flow in connection with ground roads that are expected to become stagnant owing to the increase in underground road infrastructure, and to derive methods to solve the problem in the future. METHODS : The basic design of underground roads is similar to that of tunnels. However, there is a point where the slope is large as the entering and exiting sections move underground. The ability of a heavy vehicle to assume a mound may vary depending on the slope. Therefore, in this study, a connection path section with a long slope was constructed using VISSIM, a simulation program, and it was verified whether analysis related to the slope and heavy vehicles in an underground road can be performed in the simulation. Subsequently, an analysis was conducted by setting a scenario and an effect index. In particular, this study analyzes internal delay patterns in the event of an unexpected situation on an underground connection road by performing shock wave analysis to analyze speed reduction according to heavy vehicles and slopes. RESULTS : A correlation between the slope of the underground road and decrease in the average speed according to the increasing rate of heavy vehicles was established. It was also possible to analyze the maximum length and duration of the delay connected to the rear in the event of a delay in the underground road and the shock wave speed transmitted to the rear. The analysis showed that the rate of increase in problems owing to delays ranged from 5% to 20% for the ratio of heavy vehicles. In particular, all effect scales increased significantly at a 9% slope. CONCLUSIONS : This study analyzes the causes of land congestion (slope and heavy vehicle mixing rate), which can be a major problem in underground roads in the future. In the future, by establishing lane-specific speed control strategies and lane control strategies based on this study, it will be necessary to derive solutions such as introducing traffic safety on the underground road by minimizing the shock wave delivered to the rear by providing information on traffic communication conditions inside the underground road to individual vehicles.

Single OLED and tandem OLED was manufactured to analyze the electroluminescence characteristics of DC driving, AC driving, and full-wave rectification driving. The threshold voltage of OLED was the highest in DC driving, and the lowest in full-wave rectification driving due to an improvement of current injection characteristics. The luminance at a driving voltage lower than 10.5 V (8,534 cd/m2) of single OLED and 20 V (7,377 cd/m2) of a tandem OLED showed that the full-wave rectification drive is higher than that of DC drive. The luminous efficiency of OLED is higher in full-wave rectification driving than in DC driving at low voltage, but decrease at high voltage. The full-wave rectification power source may obtain higher current density, higher luminance, and higher current efficiency than the AC power source. In addition, it was confirmed that the characteristics of AC driving and full-wave rectification driving can be predicted from DC driving characteristics by comparing the measured values and calculated values of AC driving and full-wave rectification driving emission characteristics. From the above results, it can be seen that OLED lighting with improved electroluminescence characteristics compared to DC driving is possible using full-wave rectification driving and tandem OLED.

This paper proposes a mathematical model that can calculate the luminescence characteristics driven by alternating current (AC) power using the current-voltage-luminance (I-V-L) properties of organic light emitting devices (OLED) driven by direct current power. Fluorescent OLEDs are manufactured to verify the model, and I-V-L characteristics driven by DC and AC are measured. The current efficiency of DC driven OLED can be divided into three sections. Region 1 is a section where the recombination efficiency increases as the carrier reaches the emission layer in proportion to the increase of the DC voltage. Region 2 is a section in which the maximum luminous efficiency is stably maintained. Region 3 is a section where the luminous efficiency decreases due to excess carriers. Therefore, the fitting equation is derived by dividing the current density and luminance of the DC driven OLED into three regions, and the current density and luminance of the AC driven OLED are calculated from the fitting equation. As a result, the measured and calculated values of the AC driving I-V-L characteristics show deviations of 4.7% for current density, 2.9% for luminance, and 1.9% for luminous efficiency.

목적 : 본 연구의 목적은 애들레이드 운전 자기효능감 척도(Adelaide Driving Self-Efficacy Scale)를 한국 문화에 맞게 번안하여 임상 적용을 위한 심리측정학적 특성을 파악하는 데 있다. 연구방법 : 한국형 애들레이드 운전 자기효능감 척도(K-ADSES)는 전문가 집단에 의한 번역 및 검증을 거쳐 개발되었다. 완성된 K-ADSES에 대한 신뢰도와 타당도 검증을 위해 운전 경험이 1년 이상인 노 인 114명을 대상으로 K-ADSES, 한국형 자가 보고식 안전 운전 행동 척도(K-SDBM), 한국형 노인 자가 운전 평가(K-Driver 65 plus)를 실시하였다. 결과 : 내용 타당도 검증 결과 전체 12항목의 CVI 점수는 평균 .95점이었다. 수렴 타당도 검증을 위해 실시한 평가들의 상관성을 분석한 결과 K-ADSES의 총점과 한국형 노인 자가 운전 평가의 총점은 r=-.644(p<.001), K-ADSES의 총점과 한국형 자가 보고식 안전 운전 행동 척도의 총점은 r=.792 (p<.001)의 통계학적으로 유의미한 상관성을 나타내었다. K-ADSES의 내적 일치도를 검증한 Cronbach's α값은 .975로 높은 신뢰도를 나타내었으며, 검사-재검사 신뢰도 검증 결과, 급간내 상관계수가 .813으로 통계학적으로 유의미한 상관성을 나타내었다. 결론 : K-ADSES은 신뢰도와 타당도를 갖춘 노인 운전자의 운전에 대한 자기효능감 측정 도구임이 확인 되었다. 본 연구를 토대로 K-ADSES가 운전에 관한 자기효능감 평가도구가 미비한 국내의 운전 재활 임상 환경에서 노인 운전자 및 운전 취약계층의 운전 관련 자기효능감을 측정하기 위한 도구로 널리 활용되기를 기대한다.

Speeding is one of the principal causes of traffic accidents that harm not only the safety of pedestrians but also the driver himself and others. However, empirical studies on speeding behavior are mostly survey research and identification of cause-and-effect relationship is unclear. Also the reliability of the study results cannot be verified using retrospective methods. To complement this point, it is important to conduct an experimental study, but realworld field research using real vehicles is almost impossible to apply equally to all subjects by controlling surrounding vehicles and signal systems. Therefore, in this study, we compared the overspeed characteristics of high risk driver types using driving simulator. The high risk driver types were divided in to four types: elderly driver, commercial driver, driver with more than 10 years of driving experience, and driver within 2 years of license acquisition. The overspeed characteristics were identified by using an index called Accumulated Speeding (AS). Based on overspeed characteristics differences between driver types, it is expected that additional education by driver type will be possible in the safety education using Driving Simulator.

PURPOSES : Because elderly drivers are more prone to becoming confused when approaching an urban intersection and thus may yield prolong judgment and decision times than non-elderly drivers, to increase the comfort and safety of the intersection environment for elderly drivers, this study applied autonomous driving tests at an urban intersection to examine their driving characteristics. METHODS: To obtain a more comprehensive understanding of driving features, this study collected drive data of non-elderly drivers and elderly drivers via an autonomous experiment using OBD2 and an eye-tracker, in addition to performing a literature review on the measured visibility range of elderly drivers at intersections. This literature review was conducted considering the general knowledge of elderly drivers having relatively reduced visibility. Additionally, as they are commonly more vulnerable, this study analyzes characteristics of elderly drivers as compared to those of non-elderly drivers. CONCLUSIONS: The results of this study can be summarized as follows: 1) the peripheral visible distance of elderly drivers is reduced as compared to that of non-elderly drivers; 2) elderly drivers approach and proceed through intersections at slower speeds than non-elderly drivers; and 3) elderly drivers yield increased driving distances when performing a right or left turn as compared to non-elderly drivers as a result of their reduced speed and acceleration and larger turning radii relative to non-elderly drivers.

The purpose of this study was to examine drivers’ driving behaviors and eye-movements according to driving speed and navigation-position while operation of the navigation in driving. For this purpose, two driving conditions (low-speed and high-speed) and

고속도로 및 국도 등의 인터체인지 유출부에 대한 설계기준과 연구 내용은 주로 변이구간, 감속차로, 곡선반경, 유출각 및 노즈부의 형상 등 자동차와 도로 기하구조간의 운동역학적인 관점의 안전성 확보만 주요 관심사였다. 따라서 본 연구에서는 차량 주행속도 특성에 초점을 맞추어 첫째 현행 설계기준의 이론적 의미를 해석하고, 둘째, 유출부 완화곡선에서 차량의 주행속도 및 교통사고 특성을 살펴보았고, 셋째, 기존의 인터체인지 유출 램프부 최소곡선반경의 부적합성을 검토한 후 운전자의 완화 곡선부 주행특성에 맞는 새로운 완화곡선 설계방법을 제시하였고 그 결과를 산출하여 기존방법과 비교 검토한 결과 유출램프 완화 곡선부 설계속도 50km/h, 40km/h의 경우기존의 원심력과 구심력이 평형을 이루는 최소곡선반경에서 관성력이 커져 교통사고의 위험이 높아진다는 것을 확인할 수 있었고 새로이 제안한 감속주행 완화곡선에서는 기존의 완화곡선보다 관성력이 작아지고 곡선은 커져 기존보다 안전한 곡선으로 확인되었다.

It's declining the number of deaths in total traffic accidents, but the death of elder drivers has increasing than younger drivers. So this paper wish to prevent the traffic accident of the elder drivers using driving simulator. It can help to make better policies and planning for elder drivers.

The purpose of this study was to provide information on driving characteristics in persons with spinal cord injury through basic statistic analysis of the survey results. The survey was administered to 44 drivers with spinal cord injury. The subjects' general, neurologic and driving characteristics were analyzed, as well as the degree of difficulty in using their vehicles between tetraplegia and paraplegia. The results were as follows: thirty-five (79.6%) of forty-four respondents was men. The average age was 35.0 years old and the age at the time of injury was 29.0 years old. Their neurologic characteristics were tetraplegics 12 (27.3%) and paraplegics 32 (72.2%). Among complete lesions, the highest level those who could drive independently was C7. All the vehicles were equipped with special devices, including "power steering", "automatic transmission" and "hand controls". The vehicles for cervical cord injury were equipped with "grip bars" as well as for the degree of difficulty in using their vehicles, all the subjects felt that "moving the wheelchair in and out of their vehicles" was too difficult for them to do. We suggest that the driver training should be an essential part of the rehabilitation program for patients with spinal cord injuries to maximize their mobility in the community. This training seems to be essential in order to modify the standards of the Handicapped Drivers Ability Test and to aid the driver rehabilitation program in the health insurance payment system. Also, the driver rehabilitation training program should include instruction in that moving wheelchairs in and out of vehicles.

To provide the pleasant residential environment, the concern for the noise of concrete pile has increased at construction site. In this study, the noise characteristics of non-noise pile driving method by scale model were compared when the noise breaker was applied. From the test results, the noise characteristics are affected by the noise breaker

논문에서는 전력용반도체 소자의 수명예측으로 기초적인 동작환경과 구동시간들을 기록하였다. 전력변환기의 제어기에 의하여 전력소자의 구동시간과 방렬기의 온도 등 동작환경을 누적하여 기록하고 이를 확인할 수 있도록 하므로써전력용 반도체소자는 그 구조에서 수명은 반도체 칩의 온도변화의 크기와 반복회수로 사용기간을 보증하고 있으므로이에 의한 수명의 예측으로 유지보수 또는 교체가 적절한 시점에서 이루어질 수 있다고 판단된다.