• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.1
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• pp.233-251
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• 2023

Metropolitan buses are managed as either a direct seat type or a metropolitan express type according to the 「Passenger Transport Service Act」. However, a management system that reflects the characteristics of metropolitan buses is not currently established. Therefore, in this study, the driving characteristics of metropolitan buses, dangerous driving behavior characteristics of metropolitan bus drivers, metropolitan bus accident characteristics, and the safety management system of domestic and foreign buses and other means were investigated. Through this, a plan for strengthening the safety management of metropolitan buses suitable for Korea was presented by dividing it into short-term and mid to long term. The short-term plan is a plan that can be carried out through consultation between metropolitan bus agencies and transportation companies, and the mid to long term plan is a plan that can be implemented only when related laws are revised. Through this study, it is expected to serve as an opportunity for in-depth discussions by the government, business operators, and related experts to strengthen the safety management of metropolitan buses.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.4
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• pp.683-690
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• 2012

In this work, the semi-active control of a large-sized bus suspension system with an MR damper was studied. An MR damper model that can aptly describe the hysteretic characteristics of an MR damper was adopted. Parameter values of the MR damper model were suitably modified by considering the maximum damping force of a passive damper used in the suspension system of a real large-sized bus. In addition, a fuzzy logic controller was developed for semi-active control of a suspension system with an MR damper. The vertical acceleration at the attachment point of the MR damper and the relative velocity between sprung and unsprung masses were used as input variables, while voltage was used as the output variable. Straight-ahead driving simulations were performed on a road with a random road profile and on a flat road with a bump. In straight-ahead driving simulations, the vertical acceleration and pitch angle were measured to compare the riding performance of a suspension system with a passive damper with that of a suspension with an MR damper. In addition, a single lane change simulation was performed. In the simulation, the lateral acceleration and roll angle were measured in order to compare the handling performance of a suspension system using a passive damper with that of a suspension system using an MR damper.

• Safety and Health at Work
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• v.9 no.4
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• pp.454-461
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• 2018

Background: Working conditions and psychosocial work factors have acquired an important role explaining the well-being and performance of professional drivers, including those working in the field of public transport. This study aimed to examine the association between job strain and the operational performance of public transport drivers and to compare the expositions with psychosocial risk at work of three different types of transport workers: taxi drivers, city bus drivers, and interurban bus drivers. Method: A sample of 780 professional drivers was drawn from three transport companies in Bogota (Colombia). The participants answered the Job Content Questionnaire and a set of sociodemographic and driving performance questions, including age, professional driving experience, work schedules, and accidents and penalties suffered in the last 2 years. Results: Analyses showed significant associations between measures of socio-labor variables and key performance indicators such road traffic accidents and penalties. Furthermore, multiple linear regression analysis contributed to explain significantly suffered accidents from key variables of the Job Demand-Control model, essentially from job strain. In addition, throughout post-hoc analyses, significant differences were found in terms of perceived social support, job strain, and job insecurity. Conclusion: Work stress is an issue that compromises the safety of professional drivers. This research provides evidence supporting a significant effect of job strain on the professional driver's performance. Moreover, the statistically significant differences between taxi drivers, city bus drivers, and interurban bus drivers in their expositions to work-related stress suggest the need for tailored occupational safety interventions on each occupational group.

• Journal of Auto-vehicle Safety Association
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• v.14 no.1
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• pp.26-31
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• 2022

Changwon City has the second highest accident rate with 79.6 according to the city bus accident rate. In fact, 250,000 people use the city bus a day in Changwon, The number of accidents is increasing gradually. In addition, a recent fire accident occurred in the engine room of a city bus (CNG) in Changwon, which has gradually expanded the public's anxiety. In the case of business vehicles, the government conducts inspections with a short inspection cycle for the purpose of periodic safety inspections, etc., but it is not in the monitoring stage. In the case of city buses, the operation records are monitored using Digital Tacho Graph (DTG). As such, driving records, methods, etc. are continuously monitored, but inspections are conducted every six months to ascertain the safety and performance of automobiles. It is difficult to identify real-time information on automobile safety. Therefore, in this study, individual automobile management solutions are presented through machine learning techniques of inspection results based on driving records or habits by linking DTG data and Vehicle Inspection Management System (VIMS) data for city buses in Changwon from 2019 to 2020.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.536-538
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• 2009

In recent day, many people are interested in wind resource for generation of electric power. Especially, it is made assessment the possibility of generation of electric power by wind resource originated from running cars and buses in downtown or highway. Moreover bus, driven in the exclusive lane, is focused on possibility of generation electric power on highway because median strip makes fast flow way between bus body and median strip and a pattern will appear in the flow way like drag coefficient. But nobody can guess whether the induced flow will increase or decrease and estimate amount of change of drag coefficient. Solving drag coefficient of bus running highway is the point of this paper. To solve this problem, we use the CFD method. The model is a bus simplified without mirror and gates. In order to assess result, the flow analysis surrounding the bus on the flat road where median strip is not installed has been compared with road with median strip. Solving condition is that the driving highway and median strip are running with 100km/h (27.8m/s).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.414-417
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• 2001

In this paper the fuel filling system for a city bus was investigated in order to improve the system. The suggested fuel filling system was designed to have functions of identifying a bus arrival tine, and measuring volume of fuel filled. The system consisted of four parts of bus identification, IBM PC, interface card, fuel filling control system and program for integrating all parts. It is believed that the information obtained by this system can be used for analysing driver's driving habits and performance of engine of a bus, and accordingly the prime cost can be reduced.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2010.09a
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• pp.326-329
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• 2010

현재 시행 중인 승용차 RFID 요일제는 제한적인 설치장소와 RFID 설치시 많은 비용이 소비된다. 따라서 본 연구에서는 기존의 RFID 승용차 요일제 방식과 달리 효율성을 높이고 비용을 절감할수 있는 BMS(BUS Management System)를 활용한 버스 RFID system에 관한 방안을 제안한다. 제안하는 방안은 버스 RFID system은 대구시의 시내 버스 뒤편에 양쪽 상단에 RFID 안테나를 설치하여 대구시의 주요 도로를 운행 하며 승용차 요일제를 미준수 여부를 파악하는 것이다. 기존의 고정형 RFID는 설치 위치를 우회 할수 있지만 버스 RFID는 항상 이동하며 감지 하기때문에 차량의 우회에 따른 미확인 경우를 줄일 수 있다. 또한, BMS 활용으로 설치비용을 절감하여 비용대비 효율성을 제고할 수 있을 것으로 예상된다. 구체적인 방안 마련을 위하여 주요도로 버스노선도 파악, 중첩지점 그리고 기존의 승용차 요일제 시스템과 비교 분석을 하여 성능 평가들 실시하는 것에 주안점을 두고 연구를 수행하였다.

• International Journal of Fluid Machinery and Systems
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• v.8 no.1
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• pp.13-22
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• 2015

This study presents a simulation model of a heat pump air conditioning system with a variable capacity compressor and variable speeds fans for electric bus. An experimental sample has been developed in order to check results from the model. Effects on system performance of such working conditions as compressor speed, evaporator fans speeds and the condenser fans speeds have been simulated by means of developed model. The results show that the three speeds can be adjusted simultaneously according to actual working condition so that the AC system can operate under the optimum state which the control objects want to achieve. It would be a good and simple solution to extend the driving ranges of EVs because of the highest efficiency and the lowest energy consumption of AC system.

• Journal of Mechanical Science and Technology
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• v.15 no.10
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• pp.1398-1407
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• 2001

In this paper an anti-lock brake system (ABS) for commercial buses is proposed based on a fuzzy-logic controller and a sliding-mode observer of the vehicle speed. The brake controller generates pulse width modulated (PWM) control inputs to the solenoid valve of each brake, as a function of the estimated wheel slip ratio. PWM control inputs at the brakes significantly reduce chattering in the brake system compared with conventional on-off control inputs. The sliding-mode observer estimates the vehicle speed with measurements of wheel speed, which is then sed to compute the wheel slip ratio. The effectiveness of the proposed control algorithm is validated by a series of computer simulations of bus driving, where the 14-DOF bus model is used.

• Korean Journal of Culture and Social Issue
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• v.22 no.1
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• pp.19-39
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• 2016

Though research has shown that public transportation drivers experience greater burnout than other drivers, the sources of their burnout and possible mediators remain largely unknown. In response, in this study we investigate the relationships among sensation seeking, Type A driving behavior, and meaning of work to elucidate the burnout experienced by bus drivers in Gyeonggi-do, South Korea. To collect data regarding these relationships, 188 bus drivers answered a questionnaire involving the sensation seeking scale, burnout scale, and meaning of work scale. Results showed that Type A driving behavior mediated the relationship between sensation seeking and burnout, while meaning of work moderated the mediated model. These findings demonstrate that sensation-seeking bus drivers tend to experience greater burnout given their tendency to exhibit Type A driving behavior, and this relationship depends on perceived meaning of work. This study therefore contributes meaningful information and outlines significant implications in understanding drivers' burnout.