• Proceedings of the KSR Conference
• /
• 2011.05a
• /
• pp.1440-1444
• /
• 2011

Memory-device is one of the auxiliary components of point-switch machine; connecting front-rod and tongue-rail. The right side and left side of memory-device are different from each other. When there would be a derailing accident of rolling stock or motor-car, the memory-device properly bends and protects the internal of point-switch machine. Memory-device is one of the important site maintenance spare parts. Memory-device for each of right and left side should be secured so that they can be installed on correct side during an exchange work. This study suggests the development of memory-device with different left and right side and the performance test of it. The study intends to contribute in the convenience improvement of maintenance by improving the unification of memory-device.

• 제어로봇시스템학회:학술대회논문집
• /
• 2002.10a
• /
• pp.77.4-77
• /
• 2002

Communicating devices for the seriously disabled using eye-ball movement or some body movement are proposed. The first one is a device to use image processing, whose input signal is eyeball movement, A feature of this device is that the device can be readily realized using a note-book computer with USB (Universal Serial Bus) interface bus. This device is incorporated with a word processing software called Nearly Ladder. The second one is an emergency call switch which is used by a patient who can move his finger slightly. The patients can switch on the emergency switch only by touching a switch with his finger. The essence of this sensor is a touch sensor. The sensor can be realized using onl...

• Proceedings of the Korea Institute of Convergence Signal Processing
• /
• 2001.06a
• /
• pp.81-84
• /
• 2001

A signal path control switch has been designed and implemented with AT&T 0.5${\mu}{\textrm}{m}$ CMOS ORCA FPGA. This device controls the path of digital signals in SDH-based transmission system. The proposed switch is suitable for self-healing operation which protects against transmission network failure. The self-healing operation of the switch is effectively done by the reconfigurable information stored in the registers of the switch. This device consists of eight subparts such west-east transmitting parts, west-east receiving parts, add-drop control parts, AIS control Part, and CPU interface part. The device is capable to a ring network as well as a linear network.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.1334-1338
• /
• 2005

A limit switch box is used for an indicator of a valve actuator. This device indicates an opening and closing of a valve or a throttle in the valve actuator. In a ship, equipments require safety and robustness because of a rough environment and a specific condition during a voyage. However, the limit switch box has been used in an indoor environment generally. This study developed a new limit switch box which can be used at an outdoor environment. This study designed the new limit switch box. The housing of the limit switch box was made by an aluminum die cast method with surface painting after anodizing or chromate coating. In order to evaluate the endurance of the housing, the endurance tests against salt water have been conducted. Experiment results showed that the proposed device provides a reliable performance against salt water.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.19 no.11
• /
• pp.1287-1293
• /
• 2008

Antenna switch module(ASM) for quad-band was developed. This module was integrated by RFIPD(RF integrated passive device) and transistor switch instead of LTCC-type device using low pass filters, diodes and passive elements in RF front end module for cellular phone. This module leads to low cost and miniaturization(The area is $5{\times}5\;mm$ and the thickness is 0.8 mm). The insertion loss and the return loss of each band were averagely measured as 1.0 dB(insertion loss), 15.1 dB(GSM/EGSM return loss) and 19 dB(DCS/PCS return loss), respectively.

• Structural Engineering and Mechanics
• /
• v.22 no.4
• /
• pp.433-447
• /
• 2006

The problem of very large deflection of a circular cantilever arc device subjected to inward or outward polar force is studied. An exact elliptic integral solution is derived for the two cases and the results are checked using large displacement finite element analysis via the ANSYS package by performing a new novel modeling simulation technique for this problem. Excellent agreements have been obtained between the exact analytical solution and the numerical approach. From this study, a design chart for engineers is developed to predict the required value for the inward polar force for the device to switch on for a given angle forming the circular arc (${\theta}_o$). This study has several interesting applications in mechanical engineering, integrated circuit technology, nanotechnology and especially in microelectromechanical systems (MEMs) such as a MEM circular device switch subjected to attractive or repulsive magnetic forces due to the attachments of two magnetic poles at the fixed and at the free end of the circular cantilever arc switch device.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.10
• /
• pp.1829-1834
• /
• 2008

An optical switch/modulator is designed and the light propagating characteristics is analyzed by the simplified BPM. The distinctive feature of the switch/modulator is that all the waveguide branches are designed to be single-mode. Principle of the device is based on the coupled mode theory in the Y-junction interconnecting waveguide. In spite of all the waveguides are designed to be single-mode, adjusting the interconnecting waveguide length of the device, the same characteristics as existing device up to date is obtainable. Numerical results show that the switching characteristics periodically depends on the interconnecting waveguide length with a spatial of about 150${\mu}m$ in the Ti:LiNbO3 step index waveguide. The concept of design would be utilized effectively in fabricating the monolithic high density of optical integrated circuit.

• Proceedings of the KIPE Conference
• /
• 2017.11a
• /
• pp.133-134
• /
• 2017

This paper analyzes switch Device losses and efficiency depending on SiC and Si devices. The switch devices loss is compared to Si and SiC-based elements through Threshold Voltage and Miller Platequ Voltage. And analyzed through comparison of each switching loss by experiment.

• Proceedings of the KIPE Conference
• /
• 2012.07a
• /
• pp.230-231
• /
• 2012

This paper describes a gate driver that operates numerous semiconductor switch in the solide-state pulsed power modulator. the proposed gate driver is designed to receive both the isolated drive-power and the on/off pulse signals through the transformer. Moreover, the IGBT-switch can be quickly turned off by adding protection circuit. Therefore it protects the IGBT-switch from the arc condition that frequently occurs in high-voltage pulse application. To comprehend operating characteristic of each IGBT-switch in pulse output condition, the device consisting of a high efficiency soft-switching capacitor charger and two series stacking IGBT-switch is developed. Finally, the relability of the proposed gate driver and the device for its test are proved through PSpice simulation and experiments.

• Journal of Power Electronics
• /
• v.18 no.6
• /
• pp.1912-1919
• /
• 2018

The output capacitance of power semiconductor devices is important in determining the switching losses and in the operation of some resonant converter topologies. Thus, it is important to be able to accurately determine the output capacitance of a particular device operating at elevated power levels so that the contribution of the output capacitance discharge to switch-on losses can be determined under these conditions. Power semiconductor switch manufacturers usually measure device output capacitance using small-signal methods that may be insufficient for power switching applications. This paper shows how first principle methods are applied in a novel way to obtain more relevant large signal output capacitances of Gallium-Nitride (GaN) FETs using the drain-source voltage transient during device switch-off numerically. A non-linear capacitance for an increase in voltage is determined with good correlation. Simulations are verified using experimental results from two different devices. It is shown that the large signal output capacitance as a function of the drain-source voltage is higher than the small signal values published in the data sheets for each of the devices. It can also be seen that the loss contribution of the output capacitance discharging in the channel during switch-on correlates well with other methods proposed in the literature, which confirms that the proposed method has merit.