• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.123-129
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• 2002

This paper proposes a vehicle trajectory prediction method far application to vehicle-to-vehicle distance control. This method is based on 2-dimensional kinematics and a Kalman filter has been used to estimate acceleration of the object vehicle. The simulation results using the proposed control method show that the relative distance characteristics can be improved via the trajectory prediction method compared to the customary intelligent cruise control algorithm.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.1
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• pp.153-161
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• 2004

A vehicle fuel economy is one of the most important issues in view of environmental regulation and customer's needs. In order to improve the vehicle fuel economy, great efforts has been carried out on the components bases. However, systematic analysis of vehicle fuel consumption is necessary for the further improvement of vehicle fuel economy. In this paper, a methodology for the breakdown of vehicle fuel consumption was studied and proposed for systematic analysis of the vehicle fuel economy. The energy equation for the vehicle power train was set up for the analysis of the vehicle fuel economy and simplified to be calculated or estimated using the measured data in a vehicle. The amount of fuel that was used in vehicle components under arbitrary driving conditions was quantified.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.430-435
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• 2008

Hyundai-Rotem Company has designed and manufactured Light Railway Vehicle (LRV) according to the Urban Rail Transit Code, which applies to urban railway vehicles in Korea. The Urban Rail Transit Code specifies the loads, for which vehicle bodies shall be capable of withstanding, identifies how material data shall be used and presents the principles to be used for design verification by analysis and test. The structural design of railway vehicle bodies depends on the loads they are subjected to and the characteristics of the materials they are manufactured from. Therefore Hyundai-Rotem Company has carried out Finite Element Analysis (FEA) and has performed load tests on the vehicle body according to the Urban Rail Transit Code. This research contains the results obtained by the analysis and the load tests. The analysis was carried out using I-DEAS Master Series 12 and load test were carried out using specially designed test jigs and equipment are used for the load tests.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2147-2152
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• 2011

This study of bimodal integration management system in conjunction with the tram and the tram cars bimodal integrated management system that occupies a part of the system to perform its role as a bimodal tram vehicle configuration, a device for the vehicle's infrastructure ryureul development and it is aimed to build on the vehicle. Bimodal tram vehicle infrastructure systems, internal and external information of the larger vehicles, and vehicles used to collect information for its own part and the integrated operations management center, or providing partial information from the station and collect/provide for the transfer of information to the communication part consists In this study, the core of these devices, the configuration of the vehicle infrastructure systems for the overall management and control of vehicles operating a computer's central processing device, vehicle infrastructure systems that make it manages and stores all jangchiryu Integrated Operations Management Center is reporting. In addition, seamless integration with operational management center for interactive communication in a vehicle mounted communications devices to maintain the best condition to manage. Current general traffic management system in a similar terminal device being used, but bimodal tram vehicles operating the computer of the vehicle operates the infrastructure to configure the devices around the one to configure the system in terms of step enhanced the active type, the operating terminal unit of inter active type. In this study, considering the future alignment of the accounting fee system, the expansion of the system reliability and stability around the activities that are underway.

• Structural Engineering and Mechanics
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• v.52 no.6
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• pp.1085-1098
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• 2014

Plastic mechanism analysis of structures subjected to large deformation has long been used in order to determine collapse mechanisms of steel structures, and the energy absorbed in plastic deformation during such collapses. In this paper the technique is applied to vehicle roof structures that undergo large plastic deformation as a result of rollover crashes. The components of such roof structures are typically steel spot-welded hat-type sections. Ten different deformation mechanisms are defined from investigations of real-world rollover crashes, and an analytical technique to determine the plastic collapse load and energy absorption of such mechanisms is determined. The procedure is presented in a generic manner, such that it may be applied to any vehicle structure undergoing a rollover induced collapse. The procedure is applied to an exemplar vehicle, in order to demonstrate its application in determining the energy absorbed in the deformation of the identified collapse mechanisms. The procedure will be useful to forensic crash reconstructionists, in order to accurately determine the initial travel velocity of a vehicle that has undergone a rollover and for which the post-crash vehicle deformation is known. It may also be used to perform analytical studies of the collapse resistance of vehicle roof structures for optimisation purposes, which is also demonstrated with an analysis of the effect of varying the geometric and material properties of the roof structure components of the exemplar vehicle.

• Structural Engineering and Mechanics
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• v.46 no.1
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• pp.75-90
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• 2013

In order to identify damage of highway bridges rapidly, a method for damage identification using dynamic response of bridge induced by moving vehicle and static test data is proposed. To locate damage of the structure, displacement energy damage index defined from the energy of the displacement response time history is adopted as the indicator. The displacement response time histories of bridge structure are obtained from simulation of vehicle-bridge coupled vibration analysis. The vehicle model is considered as a four-degree-of-freedom system, and the vibration equations of the vehicle model are deduced based on the D'Alembert principle. Finite element method is used to discretize bridge and finite element model is set up. According to the condition of displacement and force compatibility between vehicle and bridge, the vibration equations of the vehicle and bridge models are coupled. A Newmark-${\beta}$ algorithm based professional procedure VBAP is developed in MATLAB, and used to analyze the vehicle-bridge system coupled vibration. After damage is located by employing the displacement energy damage index, the damage extent is estimated through the least-square-method based model updating using static test data. At last, taking one simply supported bridge as an illustrative example, some damage scenarios are identified using the proposed damage identification methodology. The results indicate that the proposed method is efficient for damage localization and damage extent estimation.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.9
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• pp.881-887
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• 2015

The hardware-in-the-loop simulation (HILS) of a railway vehicle is crucial for overcoming the limitation of field tests of a railway vehicle. A brake HILS system for a railway vehicle was previously not able to test the performance of a speed-sensing system of a railway vehicle, since wheelset speeds were generated only by computer simulations. In this paper, we present a novel wheelset speed implementation of a brake HILS system for a railway vehicle. Four wheelset speeds of a brake HILS system for a car of a railway vehicle are implemented using four small-sized servomotors, whereas the speed sensors and pole wheels used in the brake HILS system are the actual ones of the railway vehicle. According to the simulated speeds of four wheelsets in the dynamic equations of motion, four servomotors generate wheel speeds in real time, and then the measured wheelset speeds are fed back to the computer simulation model. Moreover, in this paper, we improve the performance of wheelset speed measurement via the T method instead of the M method presently used in the field. The performances of wheelset speed implementation and speed-sensor operation are demonstrated by experimental works using a HILS system.

• Structural Engineering and Mechanics
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• v.51 no.2
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• pp.315-331
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• 2014

The present study investigated the effect of the correlation of the measured road roughness profiles corresponding to the left and right wheels of a vehicle on the vibration of a vehicle-bridge coupling system. Four sets of road roughness profiles were measured by a laser road-testing vehicle. A correlation analysis was carried out on the four roughness samples, and two samples with the strongest correlation and weakest correlation were selected for the power spectral density, autocorrelation and cross-correlation analyses. The scenario of a three-axle truck moving across a rigid-frame arch bridge was used as an example. The two selected road roughness profiles were used as inputs to the vehicle-bridge coupling system. Three different input modes were adopted in the numerical analysis: (1) using the measured road roughness profile of the left wheel for the input of both wheels in the numerical simulation; (2) using the measured road roughness profile of the right wheel for both wheels; and (3) using the measured road roughness profiles corresponding to left and right wheels for the input corresponding to the vehicle's left and right wheels, respectively. The influence of the three input modes on the vibration of the vehicle-bridge system was analyzed and compared in detail. The results show that the correlation of the road roughness profiles corresponding to left and right wheels and the selected roughness input mode both have a significant influence on the vibration of the vehicle-bridge coupling system.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.3
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• pp.206-221
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• 2015

Supercavitation is a modern technique which can be used to surround an underwater vehicle with a bubble in order to reduce the resistance of the vehicle. When the vehicle is at low speed in the deep sea, the cavitation number is relatively big and it is difficult to generate a cavity large enough to envelope the vehicle. In this condition, the artificial cavity, called ventilated cavity, can be used to solve this problem by supplying gas into the cavity and can maintain supercavitating condition. In this paper, a relationship between the ventilation gas supply rate and the cavity shape is determined. Based on the relationship a ventilation rate control is developed to maintain the supercavitating state. The performance of the ventilation control is verified with a depth change control. In addition, dynamics modeling for the supercavitating vehicle is performed by defining forces and moments acting on the vehicle body in contact with water. Simulation results show that the ventilation control can maintain the supercavity of an underwater vehicle at low speed in the deep sea.

• Korean Journal of Remote Sensing
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• v.38 no.1
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• pp.1-20
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• 2022

As unmanned aerial vehicle (UAV) technology grew in popularity over the years, it was introduced for air quality monitoring. This can easily be used to estimate the sidewalk emission concentration by calculating road traffic emission factors of different vehicle types. These calculations require a simulation of the spread of pollutants from one or more sources given for estimation. For this purpose, a Gaussian plume dispersion model was developed based on the US EPA Motor Vehicle Emissions Simulator (MOVES), which provides an accurate estimate of fuel consumption and pollutant emissions from vehicles under a wide range of user-defined conditions. This paper describes a methodology for estimating emission concentration on the sidewalk emitted by different types of vehicles. This line source considers vehicle parameters, wind speed and direction, and pollutant concentration using a UAV equipped with a monocular camera. All were sampled over an hourly interval. In this article, the YOLOv5 deep learning model is developed, vehicle tracking is used through Deep SORT (Simple Online and Realtime Tracking), vehicle localization using a homography transformation matrix to locate each vehicle and calculate the parameters of speed and acceleration, and ultimately a Gaussian plume dispersion model was developed to estimate the CO, NOx concentrations at a sidewalk point. The results demonstrate that these estimated pollutants values are good to give a fast and reasonable indication for any near road receptor point using a cheap UAV without installing air monitoring stations along the road.