• International Journal of Railway
• /
• v.3 no.2
• /
• pp.68-72
• /
• 2010

Railway vehicles equipped with semi-active suspension system can improve the ride quality of car bodies. Semi-active suspension system is usually applied onto high speed train, and therefore higher running safety requirement is desirable. The influence of semi-active suspension system on safety of vehicles running on straight line and curve line is studied, and the influences of sky hook damping coefficient and system time-delay on operational safety of cars fitted with semiactive suspension system is analyzed. The results show that in vehicles equipped with semi-active suspension system, while the vibration of car body is decreased, the running safety of cars is not affected to any significant degree. As a result, the ride quality is much improved with negligible deterioration of the running safety of cars.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.14 no.5
• /
• pp.115-120
• /
• 2006

A Korean Road Roughness Classification(KRC) method is proposed. Using a dynamic road profiling device equipped with the Accelerometer Established Inertial Profiling Reference(AEIPR) method, road profile measurement is performed on various types of public paved roads in Korea. The road profiling data are processed to classify the characteristics of Korean road roughness. The resultant Korean road roughness classification(KRC) is shown different characteristics compared to the road classification proposed by ISO, MIRA, and Wong. The proposed KRC is composed of 8 classes(A-H, very good-poor) based on the power spectral density and is in good agreements with the characteristics of Korean paved road roughness and can be used well in vehicle ride comfort simulation using domestic road profile.

• Proceedings of the KIPE Conference
• /
• 2012.07a
• /
• pp.207-208
• /
• 2012

최근 분산발전시스템에서 계통의 보호를 위해 계통전압 이상이 발생하더라도 일정시간 계통과의 연결을 강제하는 FRT기능이 요구되고 있으며 계통전압 불평형 시에도 계통과의 연결을 유지하도록 요구하고 있다. 이때 독립부하가 존재하는 경우 계통의 이상전압이 독립부하에 그대로 걸리게 되어 독립부하의 전압품질이 저하되는 문제가 있다. 본 논문에서는 계통전압 불평형시 FRT를 수행함과 동시에 독립부하에도 일정한 품질의 전압을 공급할 수 있는 전압보상 기법을 제안한다.

• Journal of Power System Engineering
• /
• v.17 no.4
• /
• pp.23-30
• /
• 2013

In this paper, the payload condition is considered and computer simulation is carried out to analyze the dynamic behavior of the middle-sized truck under the condition with different weight and location. The computer model for the truck is established and ADAMS/Car is employed to simulate the truck vehicle. A single lane change and bump-pass simulation are performed to evaluate the performance according to the weight and the position of it. Effects of the location and weight of commercial vehicle are analyzed. According to the simulation results, the front deck is preferred as the load location.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2001.11b
• /
• pp.1293-1299
• /
• 2001

The purpose of this study is to analyze the effects of the parameters of the mass ratio of the car body and the bogie frame in railway rolling-stock for KT-23 type passenger vehicle. According to the results of simulation and the small scale car test. optimal condition was obtained for the mass ratio of the car body and the bogie frame. Also. it is usefull to improve the technology of the ride quality of passenger vehicle.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.1545-1561
• /
• 2008

Among all transportations, railway transports have been promisingly offering excellent energy conservation and travelling time. Inevitably, they become a main role in not only transport goods but also passengers. With leap in development of technology, trains have tremendously enhanced their services in terms of speed, accessibility and comfort. However, the safety and ride quality have become a main issue as the train speed increased. The higher speeds have led the structural dynamics and health must be monitored from time to time to ensure that they are in good condition to provide reliable ride. Among all monitoring systems, the structural health monitoring (SHM) systems are imperative important due to its capability of in-situ monitoring and inherently reduce the maintenance frequencies and the huge associated cost. In this paper, SHM systems and the related non-destructive test and evaluation methods were discussed. The types of damages related to train vehicles as well as the damage hot spots are also included in this paper.

• Journal of Information Technology Applications and Management
• /
• v.28 no.5
• /
• pp.17-39
• /
• 2021

Indonesia's industrial application of digital technology is growing fast, especially in the application of mobile technology. About 1,700 digital startups are sprouting. PT Aplikasi Karya Anak Bangsa is one of those digital startups founded in 2010. This company is widely known, especially in Southeast Asia, for its products and services called 'Gojek' which was launched initially in 2015. Gojek began as a ride-hailing mobile-based application that later evolved into a Super App providing more than 20 different services in one single mobile application. After becoming Indonesian first unicorn company in 2016, Gojek now has become the first decacorn company in Indonesia, worth more than USD 10 billion since 2019. This paper aims to analyzes the technology industry in Indonesia and analyzes Gojek's background and history, its competitive status, and critical success factors. As a conclusion, we provide some advices for future development of Gojek in Indonesia and other countries in Southeast Asia's market. The advices include rebranding its overseas presence and the use of consistent brand identity across countries.

• Journal of Auto-vehicle Safety Association
• /
• v.16 no.2
• /
• pp.14-19
• /
• 2024

This paper describes autonomous emergency braking systems (AEB) for elderly drivers designed to consider their driving characteristics. With aging, perception-reaction time, and decision-making time increase accordingly. Without being aware of these performance degradations, however, changes in driving patterns due to increased alertness while driving lead to vehicle crashes. Therefore, it is necessary to develop an autonomous emergency braking system by incorporating the characteristics of the elderly driver. In order to enhance the driver acceptance of older people, perception-reaction time, alertness, and ride comfort need to be considered for conventional autonomous emergency braking systems (C-AEB). Proactive AEB(P-AEB) algorithm has been proposed to reflect human factor of elderly driver above. The performance of the proposed algorithm has been evaluated through MATLAB simulink simulation studies. It has been shown from the computer simulations that the proposed P-AEB algorithm enhances the driver acceptance of older people by improving ride comfort while ensuring safety of vehicle.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2010.05a
• /
• pp.487-488
• /
• 2010

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.665-666
• /
• 2014