• Proceedings of the KSR Conference
• /
• 2002.10a
• /
• pp.193-201
• /
• 2002

The development of railway vehicle and bogie involves the proper selection of design parameters not only to achieve high speed but also to reduce the vibration of the train. In this study an analytical model of a high speed freight car is developed to find the critical speed. The high speed freight car can generate the snake motion of the lateral and yawing motion of the car body, the bogie, and the wheelset. Numerical analysis for the nonlinear equation motions with 17 degrees of freedom showed the running stability and critical speed due to the snake motion. Also, the vibration modes of tile high speed freight car was calculated using ADAMS RAIL, which showed that the critical speed have the yawing modes of the car body and the bogie. Finally, this paper shows that the snake motion of the vehicle can be controlled with the modifications of the design parameters.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.05a
• /
• pp.694-696
• /
• 2022

In this study, in order to predict KIA's K3 used car price, we used car data registered on the K Car site from 2013 to 2021, and the variables used in the correlation analysis are model year, accident presence / absence, and driving. Distance, fuel and exhaust volume were used. Based on this data, we were able to use the Google Colab platform to analyze the correlation and, through the analysis, know if it correlates with the used car price.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.4
• /
• pp.341-346
• /
• 2011

In the development of high-speed trains, ride comfort is an important factor that determines the quality of the train. In this study, the ride comforts of high-speed trains with rigid and flexible car bodies were evaluated. The rail irregularity is used as an exciting source of the car-body bounce motion. The complex extruded structures of the car-body are modeled as shell structures using the calculated equivalent stiffness of the flexible model. The numerical results show that the ride of the rigid-body model improves as the speed increases, which is unreasonable. In contrast, the relationship between ride comfort and speed in the case of flexible-body model is reasonable. Thus, it is confirmed that the flexibility of the car body needs to be taken into consideration while fabricating a high-speed train.

• Journal of Convergence for Information Technology
• /
• v.9 no.12
• /
• pp.54-61
• /
• 2019

Recently, IITS (intelligent integrated transportation system) has been important topic in Smart City related industry. As a main objective of IITS, prevention of traffic jam (due to car accidents) has been attempted with help of advanced sensor and communication technologies. Studies show that car accident has certain correlation with some factors including characteristics of location, weather, driver's behavior, and time of day. We concentrate our study on observing auto correlativity of car accidents in terms of time of day. In this paper, we performed the ARIMA tests including ADF (augmented Dickey-Fuller) to check the three factors determining auto-regressive, stationarity, and lag order. Summary on forecasting of hourly car crash counts is presented, we show that the traffic accident data obtained in Korea can be applied to ARIMA model and present a result that traffic accidents in Korea have property of being recurrent daily basis.

• Proceedings of the KSME Conference
• /
• 2007.05b
• /
• pp.2868-2872
• /
• 2007

In this study, a passive control using a boat-tail device is conducted for a three-dimensional car model in ground proximity. We consider various boat-tails and investigate the mechanism of drag reduction by them. By varying the length and slant angle of boat-tail, we obtain drag reductions up to 40%. From the oil-surface flow visualization and hot-wire measurement, the drag reduction by the boat-tail is characterized by the shear-layer instability and reattachment on the boat-tail, forming a small separation bubble at the upstream part of boat-tail surface, resulting in the delay of main separation and drag reduction. At high slant angles, the flow fully separates and drag is nearly same as that of no control.

• Korean Journal of Computational Design and Engineering
• /
• v.13 no.3
• /
• pp.163-174
• /
• 2008

In this paper, for integrating of data on car parts we model information of parts that PDM system manages. Ontology of car parts applies existing ontology mapping research to integrate into car ontology. We propose a method for semantic integration of PLM object of MEMPHIS based on the integrated ontology. Through our method, we introduce C# ontology model to apply existing C# applications with ontology. We also classify ontology integration into three through examples and explain them. While semantically integrating PLM objects based on the integrated ontology, we explain the need for change of PLM object type and describe the process of change for PLM object type by examples.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.18 no.1
• /
• pp.44-50
• /
• 2010

Durability performance evaluation technology using Virtual Testing Method is a new concept of a vehicle design, which can reduce the automotive components design period and cost. In this paper, the fatigue life of an aluminum knuckle of a passenger car is evaluated using virtual testing method. The flexible multibody dynamic model of a front half car module is generated and solved with service loads which are measured from Belgian roads. Using a multibody dynamic analysis software, the flexible multibody dynamic simulation of a half car model is carried out and the dynamic stress profile of an aluminum knuckle is acquired. The stress profile is exported to a fatigue analysis software and durability performance of an aluminum knuckle is evaluated.

• Journal of Korean Society for Geospatial Information Science
• /
• v.18 no.3
• /
• pp.67-74
• /
• 2010

The aim of this paper is to come up with a methodology of migration for current transportation digital map in order to construct NDRM, which is the most essential map data for car navigation system. The model suggested through our study is able to efficiently produce navigable service map for route finding and guidance as well as to make the best of general road network developed by KOTI.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.4 no.2
• /
• pp.158-165
• /
• 1996

The knowledge of air flow in an engine room has become more and more important in recent car design. The fluid flow in the engine compartment was investigated by numerical analysis. Due to the complex geometry of the engine compartment, mesh generation is a time-consuming job. In this research, the "ICEM" code was used to generate meshes by the Cartesian mesh model. The Reynolds-averaged Navier Stokes equations, together with the porous flow model for radiator and condenser, were solved. Computation was performed for the steady, incompressible, and high speed viscous flow, adopting the standard K-ε turbulence model. The "STAR-CD" code was used as a solver. The effect of car front openning area on the flow in engine room was also investigated.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.871-875
• /
• 1996

The Output feedback linear quadratic regulator control is applied to the design of active suspension system using 7 DOF full car model. The performance index reflects the vehicle vertical movement, pitch and roll motion, and minimization of suspension stroke displacements in the rattle space. The elements of gain matrix are approximately decoupled so that each suspension requires only local information to generate the control force. The simulation results indicates that the output feedback LQ controller is more effective than purely passive or full state feedback active LQ controllers in following the road profile at the low frequency range and suppressing the road disturbance at the high frequency ranges.