• Proceedings of the Korea Water Resources Association Conference
• /
• 2005.05b
• /
• pp.532-537
• /
• 2005

The techniques of internally generating waves on a curve in a rectangular grid system are developed using the line source method. Numerical experiments are conducted using the extended mild-slope equations of Suh et al. (1997). For five different types of wave generation layout, numerical experiments are conducted in the cases of the propagation of waves on a flat bottom, and the refraction and shoaling of waves on a plane slope. The fifth type of wave generation, which consists of two parallel lines connected to a semicircle, shows the best solutions especially when the grid size is small enough.

• Journal of Institute of Control, Robotics and Systems
• /
• v.7 no.8
• /
• pp.675-679
• /
• 2001

This paper presents walking algorithm for a quadruped robot that does not have an upper body. Tilting motion is added to the planned walking trajectory instead of using an extra body segment that is independent on walking trajectory. Area and tracking algorithms are proposed as tilting method and compared with that of off-line tilting and that of no tilting. Computer simulation shows that stability of tilted walking is more improved than that of the usual walking algorithm for general walking paths. It also shows that the tracking method guarantees stability and best mobility.

• The KIPS Transactions:PartB
• /
• v.10B no.4
• /
• pp.451-458
• /
• 2003

Dynamic Programming Matching (DPM) is a mathematical optimization technique for sequentially structured problems, which has, over the years, played a major role in providing primary algorithms in pattern recognition fields. Most practical applications of this method in signature verification have been based on the practical implementational version proposed by Sakoe and Chiba [9], and is usually applied as a case of slope constraint p = 0. We found, in this case, a modified version of DPM by applying a heuristic (forward seeking) implementation is more efficient, offering significantly reduced processing complexity as well as slightly improved verification performance.

• Journal of the Korean Society of Safety
• /
• v.12 no.3
• /
• pp.147-154
• /
• 1997

The main purpose of this study is to investigate the failure surface in a soil mass by a excavation of the model ground. The failure mechanism of an earth structure is usually determined from field failure observations or from laboratory model tests at failure. To study the failure surface for the excavated slope, laboratory model tests were performed by changing the angle of the excavated slope and the ground condition. Results of the laboratory model tests were compared with those obtained with theoretical solutions using limit equilibrium analysis method. The results of model tests show that, there is a failure to create a straight line in the low angle of excavated surface and a create a circle as the angle increases. As the angle of excavated surface is increasing, the angle of the failure surface increases too. In the angle of the failure surface, the submerged ground is less than the dry ground at $3.2^{\circ}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1995.11a
• /
• pp.163-166
• /
• 1995

It was investigated the properties of TSC (Thermally Stimulated Current) to understand carriers behavior from long ago. Activation Energy of their properties is very important to verify electrical characteristics. So, for many years, many researchers were worked to get the activation energy, more compeletely. But, if boundary conditions were not satisfied, the values of activation energy contained several errors. In this work, to obtain the activation energy related to charged particles, the peak temperature Tp and the slope of tangential line on any coordinates of Arrhenius plot are applied. The calculation process can be denied with by computer, and the result of observation shows that the cures of calculation data and simulation data coincide very compeletely.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.43 no.6
• /
• pp.991-1000
• /
• 1994

To control nonlinear systems adaptively, we improve learning speed of neural networks and present a novel control algorithm characterized by compensation of control inputs. In an error-backpropagation algorithm for tranining multilayer neural networks(MLNN's) the effect of the slope of activation functions on learning performance is investigated and the learning speed of neural networks is improved by auto-adjusting the slope of activation functions. The control system is composed of two MLNN's, one for control and the other for identification, with the weights initialized by off-line training. The control algoritm is modified by a control strategy which compensates the control error induced by the indentification error. Computer simulations show that the proposed control algorithm is efficient in controlling a nonlinear system with abruptly changing parameters.

• Journal of Environmental Science International
• /
• v.13 no.6
• /
• pp.489-495
• /
• 2004

The purpose of this research is to apply GIS(Geographic Information System) for the road simulation and find some benefits analysis for the design processes. The northern Jeju island was selected as a case study. The 1/5,000 digital map and GIS technique were used for optimum road design of the island based on Arc View software. Using this software we can get an overlay map by combination of hill shade map, slope map, aspect map, and building buffer map. Based on the overlay map, we designed the optimum road line and performed three dimensional simulation. From the results, we found that the developed three dimensional road simulation technique using GIS technique that was very useful tool to estimate the reasonable road design before the real road construction works.

• Environmental Analysis Health and Toxicology
• /
• v.12 no.3_4
• /
• pp.75-84
• /
• 1997

Chromatographic retention behavior and separation of various phenol derivatives on a Partisil 10 ODS 3 column-with mobile phase containing $\alpha$-cyclodextrin-were systematically studied. The decrease in k' values caused by the addition of cyclodextrins in the mobile phase was based on the formation of an inclusion complex, resulting in weakening of the hydrophobic interaction between solutes and the stationary phase. The content of the organic solvent in the mobile phase also influenced k' values of the solutes, and k' values increased with a decrease of the content of organic solvent in the mobile phase. A simple equation has been derived that reveals the hyperbolic dependence of the capacity factor on the total concentration of cyclodextrin. A plot of the reciprocal of the capacity factor against (CD)$_T$ gives a straight line and the dissociation constant, K$_D$, of the inclusion complex can be calculated from the slope. The capacity factor decreased with increasing temperature. The enthalpy was calculated from the slope of van't Hoff plots. Under optimum conditions, some mixtures of phenol derivatives were able to separated successfully.

• Journal of the Korean Society of Safety
• /
• v.13 no.3
• /
• pp.135-142
• /
• 1998

This paper is to investigate the failure surface and modes in a soil mass by a excavation of the model ground. To study the failure surface for the excavated slope, centrifugal model tests were performed by changing the angle of the excavated slope(50, 75, $90^{\circ}$) and the ground condition($D_r$=60, 90%, dry and submerged ground). Excavation was simulated during the centrifuge tests by operating a valve that allowed the zinc chloride solvent to drain from the excavation. Results of model tests were compared with those obtained with theoretical solutions using limit equilibrium analysis method. The results of model tests show that, there is a failure to create a straight line in the low angle of excavated surface and a create a circle as the angle increases. Also, as the angle of excavated surface is increasing, the angle of the failure surface increases. The failure length in the submerged ground increases approximately 1.10~1.34 times more than that of the dry ground.

• Journal of the Korean Society of Safety
• /
• v.11 no.4
• /
• pp.151-155
• /
• 1996

The main purpose of this study was to develop a useful method for analysing slope stability by seepage force. The stability of an embankment impounding a water reservoir is highly depend upon the location of seepage line with the embankment, it is important to illustrate the seepage phenomenon. Of particular interest is the stability following a rapid rise change of reservoir level. Seepage forces in embankments are easily determined if frictional forces are expressed in relation to hydraulic gradient i. Seepage forces can combine with soil weights to improve stability or worsen it, depending on the direction in which the forces act ;n relation to the geometric cross section.