As conventional road traffic noise prediction models are designed to estimate long-term representative noise levels, capturing fine-scale noise fluctuations caused by real-world traffic dynamics is challenging. A previous study proposed a microscopic road traffic noise model (MTN) can calculate time-series noise levels with a resolution of 1 s using the concept of a moving noise source. In this study, two experiments were conducted to verify the accuracy of the noise prediction of the model. First, by comparing the calculated noise levels of two conventional road traffic noise models and the MTN in a simple road simulation environment, it was confirmed that the calculation error was within 3 dB(A) when calculating the 1-h equivalent noise level. Second, an experiment was conducted to verify the noise prediction error of the MTN on six actual roads. A comparison of the calculated noise level using the MTN based on traffic data collected from actual roads with the measured noise level on real roads showed that the calculated noise level achieved a mean absolute error (MAE) of 1.88 dB(A) from the equivalent noise level and 1.28 dB(A) from the maximum noise level. This was similar to the MAE of the foreign road traffic noise models. However, when the location of the receiver is within 10 m of the road, an error of more than 3 dB(A) occurs because of the simplicity of the MTN propagation model, which remains a problem that must be solved in the future. This study proved that the noise level calculation using the MTN is similar to the noise of an actual road environment. Additionally, the continuous development of the MTN is expected to make it an effective alternative for the management of road noise.

This study aims to evaluate traffic safety facilities in school zones in Busan Metropolitan City through Importance-Performance Analysis. This study investigated the traffic safety facilities in nine school zones, which have relatively more traffic accidents in Busan Metropolitan City from 2020 to 2022, through a field study and an Analytic Hierarchy Process(AHP). It identified their performance(i.e., compliance rate) and importance to derive measures for the improvement of traffic safety facilities in school zones. The field study showed that the compliance rate of starting points among traffic safety signs was low, and no speed limits were complied with the installation regulations among traffic road markings, but road safety facilities were generally well managed and operated. As a result of AHP, the order of importance was road safety facilities, traffic safety signs, and traffic road markings. More specifically, speed bumps, safety signs, and crosswalks were found to be more important than others in road safety facilities, traffic safety signs, and traffic road markings, respectively. Importance- Performance(compliance) Analysis revealed that the traffic safety facilities necessary to be most urgently improved are starting points. This result can be resorted to underlying measures to determine priorities for installing and operating traffic safety facilities in school zones.

PURPOSES : The reliability of traffic volume estimates based on location intelligence data (LID) is evaluated using various statistical techniques. There are several methods for determining statistical significance or relationships between different database sets. We propose a method that best represents the statistical difference between actual LID-based traffic volume estimates and the VDS values (i.e., true values) for the same road segment. METHODS : A total of 2,496 datasets aggregated for 1-h LID and VDS data were subjected to various statistical analyses to evaluate the consistency of the two datasets. The VDS data were defined as the true values for comparison. Four different statistical techniques (procrutes, 2-sample t-test, paired-sample t-test, and model performance rating scale) were applied. RESULTS : In cases where there is a specific pattern (e.g., traffic volume distribution considering peak and off-peak times), distribution tests such as Procrustes or Kolmogorov-Smirnov are useful because not only the prediction accuracy but also the similarity of the data distribution shape is important. CONCLUSIONS : The findings of this study provide important insight into the reliability of LID-based traffic volume estimation. To evaluate the reliability between the two groups, a paired-sample t-test was considered more appropriate than the performance evaluation measure of the machine-learning model. However, it is important to set the acceptance criteria necessary to statistically determine whether the difference between the two groups in the paired-sample t-test varies according to the given problem.

현재, 교통안전진단의 경우 차량 및 보행자의 교통사고를 미연에 방지하고 도로의 전체적인 안전을 도모하고자, 교통안전법 제34조 에 의거하여, 수행 조건에 부합한 경우 교통안전진단을 받도록 규정하고 있다. 교통안전진단의 경우 도로의 구분에 따라 다른 기준을 적용하고 있으며, 도로별 길이를 기준으로 수행 여부를 판단하고 있다. 교통안전진단의 경우 도로의 설계단계, 개시 전 단계 및 운영단계 등 3가지로 구분되어 수행되고 있으며, 각각의 단계별로 진단 수행 내용 및 범위가 조금씩 다르게 진행된다. 설계 단계에서의 교통안전진단의 경우, 해당 도로의 실시 설계 내용을 바탕으로 도로의 안전 을 판단하며, 개시 전 단계의 경우 도로의 신설 이후 운영 전 도로의 안전을 평가한다. 마지막으로 운영 단계의 교통안전진단의 경우 현재 운영 중인 도로에 대하여 도로의 안전을 평가하는 것이다. 본 연구에서는 진단단계별 교통안전진단 중 도로 설계단게에서 수행 시 발생될 수 있는 한계점을 파악하고, 이를 보완할 수 있는 방 안을 제시하여 그 효과를 분석하고자 한다. 또한, 국제 기준으로 운영되고 있는 iRAP(International Road Assessment Programme)의 SR4D( Star Rating for Design)을 통해 설계단계의 교통안전진단 수행 시 효과적이고 안전한 진단결과를 도출해내고자 한다.

Assessment of noise exposed population is to check the environment noise level and social influence in order to reduce the risks such as annoyance and disturbance that are generated by environmental noise. Also, this method suggests the preferential noise abatement policy and action plan by accurately finding the area that the noise causes harmful effect to human health. Recently, a noise map, which can predict noise in comprehensive area, is used for the assessment of noise exposed population, breaking from the methods using existing measures. In particular, countermeasure for noise can be considered more effectively by using assessment methods of noise exposed population for specific noise level, area and building types which are the main input factors in noise maps. In this study, we propose noise prediction at traffic noise due to noise map.

본 연구에서는 기존의 신호체계에서 발생하는 황색 신호 딜레마 상황에서 운전자의 상태를 파악하고 새로운 신호체계를 제안하고자 한다. 특히, 생체신호 분석을 통해 운전자 중심의 대처모형을 제안한다. 이를 위해 자동차 그래픽 시뮬레이터를 통해 교차로 도로 주행상황을 구현하여 기존의 신호체계와 본 연구에서 제안하는 신호체계에서 운전자의 생리적 반응을 관찰하여 규명하고자 한다. 따라서 대조군(기존 신호체계)과 새로운 황색 신호체계를 실험군(새로운 신호체계)으로 나누어 20대 초보 운전자를 중심으로 실험을 진행하였다. 그 결과, 대조군보다 실험군에서 교감신경의 출현이 우세하였으며 통계적으로 유의차가 인정되었다(p<0.05). 이를 통해 새로운 신호체계가 운전자가 긴장감을 유발하는 것처럼 보이지만 교감신경과 부교감신경의 비율이 6:4로 이상적인 균형으로 해석할 수 있다. 결론적으로, 본 연구에서 제안하는 대처 신호체계를 교통체계에 적용한다면 운전자가 더욱 안정적인 주행이 가능할 것으로 보인다.

PURPOSES: This paper presents the development and evaluation of the smart hardware-in-the-loop systems (SMART-HILS) that evaluate traffic signal operations of a new real-time traffic signal control system called SMART SIGNAL at the traffic management center (TMC) level. METHODS: The layouts of the hardware and software components of the SMART-HILS were introduced in this study and its performance was tested using real-time traffic signal operation algorithms embedded in the SMART SIGNAL control server by utilizing the VISSIM simulation model. In this study, the SMART-HILS management software was developed using .NET programming language. Fewer random seed numbers were used for the test scenarios by conducting statistical tests to address the shortcomings of a longer time due to the adoption of the simulation time as the real-time by the TMC server. RESULTS : It was determined that SMART-HILS can communicate with TMC and VISSIM for both upload and download directions within acceptable time constraints and evaluate new design algorithms for traffic signal timing. CONCLUSIONS : In practice, traffic engineers can utilize SMART-HILS for testing the traffic signal operation alternatives before their selection and implementation. This application could increase the productivity of traffic signal operation.

PURPOSES : This study was conducted to develop a traffic accident prediction model using traffic accident data and management and service evaluation data on bus companies in Busan, and to determine the possibility of establishing customized traffic accident prevention measures for each company. METHODS: First, we collected basic data on the characteristics of urban bus traffic accidents and conducted basic statistical analysis. Then, we developed traffic accident prediction models using Poisson regression and negative binomial regression to examine the characteristics of major items of management and service evaluation affecting traffic accidents. RESULTS : The Poisson regression model showed overdispersion; hence, the negative binomial regression model was selected. The results of the traffic accident prediction model developed using negative binomial regression are acceptable at 95% confidence level (a = 0.05). CONCLUSIONS : The traffic accident prediction model indicates that the management of the traffic record system and internal and external management items in service evaluation have a significant effect on the reduction of traffic accidents. In particular, because human factors are the main cause of traffic accidents, bus traffic accidents are expected to greatly decrease if drivers' dangerous driving behaviors are effectively controlled by bus companies.

PURPOSES : In this study, analyze the characteristics of IOC indicator 'threshold' which is needed when evaluating the traffic signal operation status with ESPRESSO in various grade road traffic environment of Seoul metropolitan city and derive suggested value to use in field practice. METHODS : Using the computerized database program (Postgresql), we extracted data with regional characteristics (Arterial, Collector road) and temporal characteristics (peak hour, non-peak hour). Analysis of variance and Duncan's validation were performed using statistical analysis program (SPSS) to confirm whether the extracted data contains statistical significance. RESULTS: The analysis period of the main and secondary arterial roads was confirmed to be suitable from 14 days to 60 days. For the arterial, it is suggested to use 20 km/h as the critical speed for PM peak hour and weekly non peak hour. It is suggested to use 25 km/h as the critical speed for AM peak hour and night non peak hour. As for the collector road, it is suggested to use 20 km/h as the critical speed for PM peak hour and weekly non peak hour. It is suggested to use 30 km/h as the critical speed for AM peak hour and night non peak hour. CONCLUSIONS : It is meaningful from a methodological point of view that it is possible to make a reasonable comparative analysis on the signal intersection pre-post analysis when the signal operation DB is renewed by breaking the existing traffic signal operation evaluation method.