• Journal of the Korean Society for Precision Engineering
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• v.16 no.7
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• pp.109-118
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• 1999

A graphic software is one of the most important components of the vehicle simulator. To increase a visual reality of the simulator, the graphic software should require several technologies such as three-dimensional graphics, graphic modeling of the vehicle and the environment, drivers biomechanical models, and real-time data processing. This study presents a real time graphic driving simulator of a construction vehicle. The graphic simulator contains the three models of the construction vehicle, the human, and the environment, and employes a neural network approach to decrease an on-line dynamic computation. An excavator model is represented using an object-oriented paradigm and contains the detailed information about a real-size vehicle. The human model is introduced for objective visual evaluations of the developed excavator model. Since the environment model plays an important role in a real-time simulator, a block-based approach is implemented and a text format is utilized for easier construction of environment. The simulation results are illustrated in order to demonstrate the applicability of developed models and the neural network approach.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.7
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• pp.527-533
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• 2002

A railway vehicle should be satisfied with the safety criteria and ride comfort of passengers. A bogie of railway vehicle Is composed of many suspension components, such as springs, dampers and etc.. that have an influence on the dynamic behavior of the train wish the wheel/rail profiles and track geometries. Therefore, it Is necessary for engineers to check the Interference between vehicle limit and construction limit with considering the vehicle's behavior, because when the vehicle is running on curved track, it should be have enough clearance from infrastructure for safely, spacially In a subway system. This paper explains the effective method of analysis for vehicle limit considering the vehicle dynamic behavior and reviews the problem of vehicle limit for the Korean Standard Urban Train. The results show that the vehicle limit is over the construction limit when the Korean Standard Urban Train runs on the curved track with 180 m radius of curve.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.3
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• pp.317-325
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• 1999

The demand of diesel engine on the construction equipment has been rapidly increased because of high thermal efficiency and fuel economy. The exhaust emission from nonroad vehicles equipped with diesel engine such as construction equipment, ship, and agricultural equipment, etc. Which are known to be harmful to human health and environment, has not been regulated in our country. But the regulation for nonroad vehicle has been already progressed in advanced country. So we investigated the contribution ratio of air pollution by construction equipment in order to establish the exhaust emission management strategy for nonroad vehicle. Based on the statistical data for construction equipment, 5 kinds of equipment are selected and tested in the engine dynamometer to determine the emission factor. And the amount of air pollutant from construction equipment are calculated by using of the emission factor and recommended exhaust emission standard for construction equipment.

• Journal of Korean Institute of Industrial Engineers
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• v.37 no.3
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• pp.171-179
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• 2011

In this paper, we deal with the vehicle routing problem that could establish operational plan of military engineer for survivability support of artillery position construction. We propose VRPTW(vehicle routing problem with time-window) model of special form that considered service level to reflect the characteristics of military operations rather than the logic of economic efficiencies in the objective function. Furthermore we suggest modified particle swarm optimization algorithm for service based vehicle routing problem solution that can be possible to search in complicated and uncertain area and control relation softly between global and local search.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.7
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• pp.1092-1099
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• 2017

This paper proposes a novel way of vehicle detection and classification based on image features. There are two main processes in the proposed system, which are database construction and vehicle classification processes. In the database construction, there is a tight censorship for choosing appropriate images of the training set under the rigorous standard. These images are trained using Haar features for vehicle detection and histogram of oriented gradients extraction for vehicle classification based on the support vector machine. Additionally, in the vehicle detection and classification processes, the region of interest is reset using a number plate to reduce complexity. In the experimental results, the proposed system had the accuracy of 0.9776 and the $F_1$ score of 0.9327 for vehicle classification.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.723-729
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• 2001

Electro-hydraulic shift control of a vehicle automatic transmission has been predominantly carried out via an open-loop control based on numerous time-consuming calibrations. Despite remarkable success in practice, the variations of system characteristics inevitably deteriorate the performance of the tuned open-loop controller. As a result, the controller parameters need to be continuously updated in order to maintain satisfactory shift quality. This paper presents a self-learning algorithm for automatic transmission shift control in a construction vehicle during inertia phase. First, an observer reconstructs the turbine acceleration signal (impossible to measure in a construction vehicle) from the readily accessible turbine speed measurement. Then, a control algorithm based on a quadratic function of the turbine acceleration is shown to guarantee the asymptotic convergence (within a specified target bound) of the error between the actual and the desired turbine accelerations. A Lyapunov argument plays a crucial role in deriving adaptive laws for control parameters. The simulation and hardware-in-the-loop simulation (HILS) studies show that the proposed algorithm actually delivers the promise of satisfactory performance despite the system characteristics variations and uncertainties.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.945-951
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• 2022

The major objective of this research is to evaluate performance of improved intersections for response time to emergency vehicle preemption. Smart technologies have been introduced to civil infrastructure systems for resilient communities. The technologies need to evaluate their effectiveness and feasibility to confirm their introduction. This research focuses on the performance of emergency vehicle preemption, represented by response time, when smart intersections are introduced in a community. The response time is determined by not only intersections but also a number of factors such as traffic, distance, road conditions, and incident types. However, the evaluation of emergency response has often ignored factors related to emergency vehicle routes. In this respect, this research synthetically analyzes geospatial and incident data using each route of emergency vehicle and conducts before-and-after evaluations. The changes in performance are analyzed by the impact of smart intersections on response time through Bayesian regression models. The result provides measures of the project's performance. This study will contribute to the body of knowledge on modeling the impacts of technology application and integrating heterogeneous data sets. It will provide a way to confirm and prove the effectiveness of introducing smart technologies to our communities.

• Proceedings of the Korean Geotechical Society Conference
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• 1990.10a
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• pp.25-34
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• 1990

For the construction of twin single track subway tunnels by NATM within close proximity of existing vehicle underpass in the highly congested area of downtown Seoul, finite element analyses were performed to evaluate the ground responses during tunnelling and also the stability and safety of the underpass structure and subway tunnels. Results of the analyses indicated the need to improve the soil beneath the underpass, and pre-grouting was carried out prior to the tunnel excavation. During tunnel construction field measurement program was implemented to confirm the results of anslyses and to control the tunnel construction procedures, thus ensuring stability of the existing structres.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1181-1182
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• 2007

Light Rail Transit (LRT) System is an urban transit system which has approximately an intermediate transportation capacity between conventional subway and bus ($5,000{\sim}25,000$ persons per hour and per direction). It is a high-tech system which operational capacity, punctuality and mobility are remarkably improved. There are some types of LRT systems such as monorail, tramway, AGT(Automated Guideway Transit), and so on. The LRT systems have been applied and being operated in about a hundred lines around the world and many projects that apply the LRT systems in Korea are being proceeded and scheduled. For the efficient management, economical construction, and safe operation of various LRT systems, the establishment of national standard is necessary such as vehicle standardized specification, vehicle performance test standard, vehicle safety standard, construction guide, operation regulation, etc. of LRT systems. This paper presents the standard specification of electrical equipment of linear induction motor type light rail vehicle, that is LIM AGT(AGT system propelled with linear induction motor) vehicle. The LIM AGT system has been applied in Japan subway and ART(Advanced Rapid Transit) system of Canada and Yongin LRT is currently under construction.

• Journal of the Korean Society for Railway
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• v.8 no.4
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• pp.379-384
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• 2005

To maintain the stability during the operation of railway vehicle, the perfect installation of rail, namely the orbit as well as the performance of the railway vehicle itself is required. The orbit of railway needs the intensity and elasticity that stands the shock and vibration due to the weight of the railway vehicle enough, Also, the driving safety during the operation of vehicle should be guaranteed, comfortable feeling of the passenger should be maintained, and the influence of the noise and vibration to the environs should be minimized. Therefore, it is necessary to develop a program that calculates the change of construction cost according to the selection of railway orbit. This study introduces the orbit design automation program according to the selection of railway orbit, and discuss the principle and the way to use of the program.