• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1995.04a
• /
• pp.316-323
• /
• 1995

This paper presents an image processing technique to get traffic information such as vehicle volume, velocity, and occupancy for measuring the traffic congestion rate. To obtain these information, two horizontal lines are previously set on the screen. A moving vehicle is detected using the gray level difference on each line, and also template matching method at night. Threshold values are determined by sampling pavement grey level, and updated dynamically to cope with the change of ambient light conditions. These technique is successfully used to calculate vehicle volume, occupancy, and velocity. This study can be applied to traffic signal control system for minimizing traffic congestion in urban areas.

• Proceedings of the KSR Conference
• /
• 2004.06a
• /
• pp.1362-1364
• /
• 2004

Recently, GPS device is used in various industries. GPS can calculate a moving train's velocity, location, and direction. In this paper, we examine a train approaching alarm device's application, possibility, and merits in the train system. Especially, we investigate solubility of trouble caused by using GPS and RF system for detecting the train's velocity, the location and direction recognition.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2003.07a
• /
• pp.321-324
• /
• 2003

We reported the method for the relatively simple equalizing pulse to reduce dynamic false contour. Equalizing pulse is determined by look-up-table and moving direction and velocity of the image. Used lookup-table is a few. If image moves to right or left, necessary LUT is only one for the velocity of 1 pixel/tvfield to right or left. This technique makes the process simple after obtaining motion information.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.33A no.11
• /
• pp.44-51
• /
• 1996

The radiation characteristics of a slot antenna in a plane conductor covered with a miving isotropic plasma layer are analyzed. The radiation null which causes distortion in radiation pattern is explainted by the zero of integrand in an asymptotic integral for radiation fields as a function of the plasma parameter and the plasma velocity. Numerical resutls for a radiation null calculated from various plasma and velocity parameters correspond to the results of two-dimensional problem.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.397-397
• /
• 2000

This paper presents a gait control scheme for teleoperation of a quadruped-walking robot. In teleoperation of a walking robot, an operator gives a real-time generated velocity command to a walking robot instead of a moving trajectory. When the direction of the velocity command is changed, the periodic gait is not available because this requires an initial foot position . This paper proposes the aperiodic gait control scheme that can converge to a periodic gait Simulation results are given to demonstrate the efficiency of the proposed control scheme.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.179-179
• /
• 2000

An adaptive neural network compensator for stick-slip friction phenomena in servo systems is proposed to supplement the traditionally available position and velocity control loops for precise motion control. The neural network compensator plays a role of canceling the effect of nonlinear slipping friction force. This enables the mechatronic systems more precise control and realistic design in the digital computer. It was confirmed that the control accuracy is more improved near zero velocity and the points of changing the moving direction through numerical simulation

• Journal of Advanced Marine Engineering and Technology
• /
• v.34 no.5
• /
• pp.617-624
• /
• 2010

Line heating is a manufacture method, which was widely used to machining a curved surface in the ship construction. The qualities using by line heating are very difference compare to the proficiency level of the engineer. So it's mainly depend on the automation equipment instead of the proficiency level engineer. In this study, it would be investigate the temperature distribution of the heating plate, which was used by the automation equipment according to line heating. The main factors are the moving velocity of the heating source, strength and the heating method separately, in temperature distribution while line heating. In this paper, it was investigated the temperature change with the vary of each three variables. The numerical result showed that peak temperature decrease if the moving velocity of the heating source increased. It can also calculate the change quantitatively that the peak temperature and temperature distribution changed linearly with the vary of the heating source.

• Smart Structures and Systems
• /
• v.23 no.3
• /
• pp.263-278
• /
• 2019

Moving train load parameters, including train speed, axle spacing, gross train weight and axle weights, are identified based on strain-monitoring data. In this paper, according to influence line theory, the classic moving force identification method is enhanced to handle time-varying velocity of the train. First, the moments that the axles move through a set of fixed points are identified from a series of pulses extracted from the second derivative of the structural strain response. Subsequently, the train speed and axle spacing are identified. In addition, based on the fact that the integral area of the structural strain response is a constant under a unit force at a unit speed, the gross train weight can be obtained from the integral area of the measured strain response. Meanwhile, the corrected second derivative peak values, in which the effect of time-varying velocity is eliminated, are selected to distribute the gross train weight. Hence the axle weights could be identified. Afterwards, numerical simulations are employed to verify the proposed method and investigate the effect of the sampling frequency on the identification accuracy. Eventually, the method is verified using the real-time strain data of a continuous steel truss railway bridge. Results show that train speed, axle spacing and gross train weight can be accurately identified in the time domain. However, only the approximate values of the axle weights could be obtained with the updated method. The identified results can provide reliable reference for determining fatigue deterioration and predicting the remaining service life of railway bridges.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.36 no.2
• /
• pp.70-79
• /
• 2024

In this study, we introduce a linear spectral method capable of simulating wave generation and transformation caused by a moving bottom in a 3-dimensional space. The governing equations are linear dynamic free-surface boundary conditions and linear kinematic free-surface boundary conditions, which are solved in Fourier space. Solved velocity potential and free-surface displacement should satisfy continuity equation and kinematic bottom boundary condition. For numerical analysis, a 4th order Runge-Kutta method was utilized to analyze the time integral. The results obtained in Fourier space can be converted into velocity potential and free-surface displacement in a real space using inverse Fourier transform. Regular waves generated by various types of moving bottoms were simulated with the linear spectral method. Additionally, obliquely generated regular waves using specified bottom movements were simulated. The results obtained from the spectral method were compared to analytical solutions, showing good agreement between the two.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.975-985
• /
• 2011

Cu-Matrix sintered brake pads and low alloyed heat resistance steel are most applied to basic brake system for high energy moving machine. In this research, we analyzed tribological characteristics for influence of air velocity between disk and pad. At low brake pressure with air flow, friction stability was decreased due to no formation of tribofilm at disk surface. But there are no significant change of friction coefficient at all test conditions. Wear rate of friction materials were decreased with increasing of air flow velocity. In result, air flow velocity influenced friction stability, wear rate of friction materials and disk but not friction coefficient.