• Transactions of the Korean Society of Automotive Engineers
• /
• v.16 no.3
• /
• pp.127-136
• /
• 2008

Vehicle stability is a very important subject in vehicle design and control, because vehicle safety is closely dependent upon its dynamic stability. The control logic for four-wheel steering(4WS) systems, in which maintaining at least the specified stability region is the control objective, was constructed using the simplified vehicle model of 3 degree-of-freedoms. The improvement of vehicle stability was verified through computer simulations for the slalom and the double lane change maneuver using the multi-body dynamic model in MSC.ADAMS.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.14 no.4
• /
• pp.52-61
• /
• 2015

PCE(Passenger Car Equivalents) is used to analysis of road capacity and LOS(Level of Service). In this study calculates PCE by number of lane and 12 vehicle type by MOLIT(Minister of Land, Infra Structure and Transport) using individual vehicle data. The results of the calculation, PCEs are increased when high vehicle classification level, many number of lanes and weekend. Heavy vehicle factors are smaller than KHCM on 4, 6 lane. Also, In this study estimates of PCE variation model by heavy vehicle percentage. Impact of Heavy vehicles on PCEs is the most sensitive on 2 lane. The results of the study, heavy vehicles low impact on PCE on multi-lane and business trips are a little in weekend.

• Proceedings of the KSME Conference
• /
• 2004.11a
• /
• pp.696-701
• /
• 2004

A vehicle cruise control algorithm using an Interacting Multiple Model (IMM)-based Multi-Target Tracking (MTT) method has been presented in this paper. The vehicle cruise control algorithm consists of three parts; track estimator using IMM-Probabilistic Data Association Filter (PDAF), a primary target vehicle determination algorithm and a single-target adaptive cruise control algorithm. Three motion models; uniform motion, lane-change motion and acceleration motion, have been adopted to distinguish large lateral motions from longitudinal motions. The models have been validated using simulated and experimental data. The improvement in the state estimation performance when using three models is verified in target tracking simulations. The performance and safety benefits of a multi-model-based MTT-ACC system is investigated via simulations using real driving radar sensor data. These simulations show system response that is more realistic and reflective of actual human driving behavior.

• Journal of Mechanical Science and Technology
• /
• v.19 no.9
• /
• pp.1742-1752
• /
• 2005

This paper presents a Multiple Target Tracking (MTT) Adaptive Cruise Control (ACC) system which consists of three parts; a multi-model-based multi-target state estimator, a primary vehicular target determination algorithm, and a single-target adaptive cruise control algorithm. Three motion models, which are validated using simulated and experimental data, are adopted to distinguish large lateral motions from longitudinally excited motions. The improvement in the state estimation performance when using three models is verified in target tracking simulations. However, the performance and safety benefits of a multi-model-based MTT-ACC system is investigated via simulations using real driving radar sensor data. The MTT-ACC system is tested under lane changing situations to examine how much the system performance is improved when multiple models are incorporated. Simulation results show system response that is more realistic and reflective of actual human driving behavior.

• Journal of IKEEE
• /
• v.22 no.3
• /
• pp.619-623
• /
• 2018

Due to the development of society, the demand for electric power has increased and the quality control of electric power has become an important issue. In order to efficiently perform such power management, we propose a DSP based power measurement system for multi-wire power measurement. Since the conventional power measurement system can measure only the power of one line, a power quality measurement device is required for each line in order to measure the power quality of the individual line. Respectively. The system proposed in this paper proposes a system capable of real-time measurement of power quality at up to 12 points using digital signal processing algorithm, and the prototype based on this system was evaluated through the official test report of Korea Electrotechnology Research Institute. As a result of the performance test, it was evaluated that the error range is excellent at ${\pm}0.3%$.

• International Journal of Automotive Technology
• /
• v.7 no.2
• /
• pp.145-154
• /
• 2006

In the companion paper, the composition and structure of the MATDYMO (Multi-Agent for Traffic Simulation with Vehicle Dynamic Model) were proposed. MATDYMO consists of the road management system, the vehicle motion control system, the driver management system, and the integration control system. Among these systems, the road management system and the integration control system were discussed In the companion paper. In this paper, the vehicle motion control system and the driver management system are discussed. The driver management system constructs the driver agent capable of having different driving styles ranging from slow and careful driving to fast and aggressive driving through the yielding index and passing index. According to these indices, the agents pass or yield their lane for other vehicles; the driver management system constructs the vehicle agents capable of representing the physical vehicle itself. A vehicle agent shows its behavior according to its dynamic characteristics. The vehicle agent contains the nonlinear subcomponents of engine, torque converter, automatic transmission, and wheels. The simulation is conducted for an interrupted flow model and its results are verified by comparison with the results from a commercial software, TRANSYT-7F. The interrupted flow model simulation is implemented for three cases. The first case analyzes the agents' behaviors in the interrupted flow model and it confirms that the agent's behavior could characterize the diversity of human behavior and vehicle well through every rule and communication frameworks. The second case analyzes the traffic signals changed at different intervals and as the acceleration rate changed. The third case analyzes the effects of the traffic signals and traffic volume. The results of these analyses showed that the change of the traffic state was closely related with the vehicle acceleration rate, traffic volume, and the traffic signal interval between intersections. These simulations confirmed that MATDYMO can represent the real traffic condition of the interrupted flow model. At the current stage of development, MATDYMO shows great promise and has significant implications on future traffic state forecasting research.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.29 no.1 s.232
• /
• pp.139-144
• /
• 2005

A vehicle cruise control algorithm using an Interacting Multiple Model (IMM)-based Multi-Target Tracking (MTT) method has been presented in this paper. The vehicle cruise control algorithm consists of three parts; track estimator using IMM-Probabilistic Data Association Filter (PDAF), a primary target vehicle determination algorithm and a single-target adaptive cruise control algorithm. Three motion models; uniform motion, lane-change motion and acceleration motion. have been adopted to distinguish large lateral motions from longitudinal motions. The models have been validated using simulated and experimental data. The improvement in the state estimation performance when using three models is verified in target tracking simulations. The performance and safety benefits of a multi-model-based MTT-ACC system is investigated via simulations using real driving radar sensor data. These simulations show system response that is more realistic and reflective of actual human driving behavior.

• Journal of Korean Society of Transportation
• /
• v.8 no.2
• /
• pp.7-25
• /
• 1990

In road traffic, road circumstances, vehicle, and driver are closely related each other. When road facilities are established in road planning, only road structure has been considered. However, relatively little work has been done regarding the relation between road circumstances and human with respect to a driver. This dissertation focuses on analysis of driver's visual characteristics to improve road circumstances. In this study, driver's visual characteristics are measured with eye-mark recorder and analyzed statistically. This study includes that visual characteristics, visual range, visual time, distribution of fixation duration, and visual moving angle with respect to road circumstances are established qualitatively and quantitatively by driving testing vehicle on streets, roads and high-ways. The main features of this study are : The driver's visual ranges are different over 10% depending on lane in multi-lanes. The visual range on two-lanes is more than twice as big as that on multi-lanes at 85% of whole vision. The right and left visual ranges by as big as that on multi-lanes at 85% of whole vision. The right and left visual ranges by as big as that on multi-lanes at 85% of whole vision. The right and left visual ranges by as big as that on multi-lanes at 85% of whole vision. The right and left visual ranges by speed are $34^{\circ}$ for 30-50km/hr, $28^{\circ}$ for 50-70km/hr, $22^{\circ}$ for 70-90km/hr and 16^{\circ} for over 90km/hr at 95% of visual rate. Accordingly, increasing speed results in narrow visual range.

• Journal of IKEEE
• /
• v.16 no.4
• /
• pp.310-315
• /
• 2012

This thesis is intended to design multi thread mobile GPGPU optimized in mobile environment, and to verify an effective thread management method of the multi thread mobile processor. In thread management, there is no management hardware and implement with software instructions. For the verification of the multi thread management method, Lane detection algorithm was implemented to compare nVidia's CUDA Architecture and the designed GPGPU in terms of thread management efficiency. The number of thread is normalized to 48 threads. An implemented Land Detection Algorithm is composed of Gaussian filter algorithm and Sobel Edge Detection algorithm. As a result, the designed GPGPU's thread efficiency is up to 2 times higher than CUDA's thread efficiency.

• Journal of Korean Society of Steel Construction
• /
• v.25 no.4
• /
• pp.335-346
• /
• 2013

AASHTO LRFD and Korean Bridge Design Code (Limit State Design) specify to consider Truck and Lane load simultaneously determined from reliability-based live load model, and impact shall be applied to the truck load while it shall not be applied to the lane load. In this paper, vehicle-bridge interaction analysis under moving truck and lane loads were performed to estimate impact factor of the cables and girders for the selected multi-cable-stayed composite bridges with 230m, 400m and 540m main span. A 6-d.o.f. vehicle was used for truck load and a series of single-axle vehicles was applied to simulate equivalent lane load. The effect of damping ratio on the impact factor was estimated and then the essential parameters to impact factor, i.e., road surface roughness and vehicle speed were considered. The road surface roughness was randomly generated based on ISO 8608 and it was applied to the truck load only in the vehicle-bridge interaction analysis. The impact factors evaluated from dynamic interaction analysis were also compared with those by the influence line method that is currently used in design practice to estimate impact factor in cable-stayed bridge.