• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.452-461
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• 2008

Previous settlement prediction method based on settlement monitoring such as hyperbolic, monden method were developed under instantaneous loading condition and have restriction to be applied to soft ground under ramp loading condition. In this study, settlement prediction method under ramp loading was developed. New settlement prediction method under ramp loading considers influence factors of consolidation settlement and increase accuracy of settlement prediction using field monitoring data after ramp loading. Large consolidation tests for ideally controlled one dimensional consolidation under ramp loading condition were performed and the settlement behavior was predicted based on the monitoring data. As a result, new prediction method is expected to have great applicability and practicability for the prediction of settlement behavior.

• Journal of Information Display
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• v.2 no.4
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• pp.39-45
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• 2001

The voltage controlled ramp(VCR) waveform has recently been introduced in the reset period prior to addressing for plasma display. However, this method results in the oscillation of the gap voltage when the ramp rate is increased so as to reduce reset period. In this paper a current controlled ramp(CCR) waveform method in the reset period is suggested. This method can suppress the oscillation of gap voltage under the condition of shorter ramp time. Moreover, the reset time can be reduced by about 30 % compared with the VCR method under the same background luminance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.226-229
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• 2001

To achieve ZnO layer with a high resistance, a new sputtering method with a Ramp method and cycled power process mode was developed. The specific resistance of the layers was in rang of $3*10^{10}{\Omega}cm$ to $2*10^{11}{\Omega}cm$. The characteristics of. ZnO thin films changed with working pressure and Ramp method were investigated by XRD(x-ray diffractometer), and SEM (scanning electron microscopy) analyses. This paper presents calculated and measured results for structures with thin ZnO layers. Measurements of SAW properties using thin ZnO layered structures will be shown. Also presented are results on the quality of ZnO films and specifics of the deposition process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.226-229
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• 2001

To achieve ZnO layer with a high resistance, a new sputtering method with a Ramp method and cycled power process mode was developed. The specific resistance of the layers was in rang of 3*10$\^$10/Ωcm to 2*10$\^$11/Ωcm. The characteristics of ZnO thin films changed with working pressure and Ramp method were investigated by XRD(x-ray diffractometer), and SEM (scanning electron microscopy) analyses. This paper presents calculated and measured results for structures with thin ZnO layers. Measurements of SAW Properties using thin ZnO layered structures will be shown. Also presented are results on the quality of ZnO films and specifics of the deposition process.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.10
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• pp.517-521
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• 2001

The voltage controlled ramp(VCR) waveform has recently been introduced in the reset period prior to addressing for plasma display. However, this method shows the oscillation of gap voltage when the ramp rate is increased in order to reduce reset period. In this paper a current controlled ramp(CCR) waveform method is suggested. This method can suppress the oscillation of gap voltge under the condition of shorter ramp time. Moreover, the reset time can be reduced about 30% compared with VCR method under the same background luminance.

• Transactions of the Society of Information Storage Systems
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• v.3 no.4
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• pp.160-166
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• 2007

In this paper, the measured electrical resistance method is proposed to analyze the ramp-tab contact during the load/unload (L/UL) process. Since this method supplies the voltage change due to the resistance change, we can easily and conveniently identify the ramp-tab contact from the acoustic emission (AE) signal. At first, we carefully deposit the conductive material on the surface of the conventional ramp by sputtering method. The ratio frequency (RF) magnetron co-sputtering system is applied to accomplish the deposited double-layers on the ramp surface. One layer is the stainless steel for the conductive layer and the other is the titanium layer for the cohesive function between the ramp surface and the stainless steel layer. In order to guarantee the stiffness and damping properties of the original ramp, the deposited conductive layer is intended to have very thin thickness. After integration the proposed ramp device into the L/UL system and networking the electrical resistance circuit, the L/UL performance is experimentally evaluated by comparing the measured electrical resistance signal and AE signal.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.436-452
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• 2008

In this study, the settlement prediction method based on field monitoring data under preloading improvement with ramp loading is developed. Settlement behavior can be predicted with field monitored settlement throughout the entire preloading process including ramp loading followed by constant loading. The developed method is verified by comparing its predicted results with results from physical model tests and field monitoring data.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.4
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• pp.434-439
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• 2011

There are about 2.4million disabled in Korea, 2009. Also, Korean society entered into an aging society. Therefore disable and elderly are getting more involved in our society. This study proposes simple ramp design for wheel chair users and welding method and condition for manufacturing. In the middle of ramp, screw jack and motor are installed so that ramp can be moved left and right side. To make the ramp moves easily, ramp was fixed by installing LM guide on both sides. Ramp production for using Nd:YAG laser certain dissimilar welding in stainless steel sheet and cold reduced carbon steel. The output was fixed by 3kW, the speed was increased to 2~7m/min, Argon was used as shielding gas and the flow rate was changed to 10~30L/min. The proper welding condition is the output 3kW and welding speed 2~5m/min.

• Tribology and Lubricants
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• v.24 no.2
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• pp.77-81
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• 2008

In this work, ramp loading scratch method was used to evaluate the scratch characteristics of HDD media and ZnO thin films. Commercially available HDD media and ZnO thin films grown on silicon(100) substrate by sol-gel method were used. As for the ZnO films, the effects of annealing temperature after the film deposition process were also investigated. A custom built scratch tester was used to scratch the specimen under a ramp loading condition. The scratch track formed by ramp loading was measured by optical microscope and Atomic Force Microscopy (AFM). The wear depth and width were used to assess the scratch characteristics of the HDD Media and ZnO thin films. The results showed that ZnO film annealed at $800^{\circ}C$ had the best scratch resistance property. Also, the HDD media showed overall better scratch resistance than the ZnO films.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2046-2052
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• 2016

Ramp metering is one of the most efficient and widely used control methods for an intelligent transportation management system on a freeway. Its objective is to control and upgrade freeway traffic by regulating the number of vehicles entering the freeway entrance ramp, in such a way that not only the alleviation of the congestion but also the smoothing of the traffic flow around the desired density level can be achieved for the maintenance of the maximum mainline throughput. When the cycle of the signal detection is larger than that of the system process, the density tracking problem needs to be considered in the form of the discrete-time system. Therefore, a discrete-time sliding mode control method is proposed for the ramp metering problem in the presence of both input constraint in the on-ramp and exogenous disturbance in the off-ramp considering the random behavior of the driver. Simulations were performed using a validated second-order macroscopic traffic flow model in Matlab environment and the simulation results indicate that proposed control method can achieve better performance than previously well-known ALINEA strategy in the sense that mainstream flow throughput is maximized and congestion is alleviated even in the presence of input constraint and exogenous disturbance.