• 유체기계공업학회:학술대회논문집
• /
• 1999.12a
• /
• pp.291-300
• /
• 1999

Currently under development is an airborne auxiliary power unit with 100 Kw equivalent power, which is composed of a centrifugal compressor, a reverse annular combustor, and a radial turbine. Air-foil bearings are used in this power unit to eliminate the oil supplying system, which can reduce the system complexity and weight. The high speed generator is adopted as an electric power generation and engine starting system, which can also eliminate the reduction gear system. Not only electric power but also pneumatic power is provided by bleeding the compressed air This power unit is aimed for the multi-purpose use such as a primary power unit In the army weapon system, an auxiliary power and environmental control unit in a next-generation tank, and a smoke generating unit.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.11a
• /
• pp.200-201
• /
• 2015

The unit modular method is one in which unit modules are prefabricated at a factory and then constructed at a construction site. That is why an important process, transporting unit module, is added in this method. The purpose of this study is to analyse the load for transporting unit module. The results of the analysis of the driving experimental runs revealed that a maximum load of 15 kN was applied on adapter block type A and a maximum load of 25 kN on adapter block type B. These loads were recorded at the points in the road test when the low-bed trailer was driving through unstable sections of the test such as stopping, restarting, passing over a speed bump or taking a left turn at speed.

• Journal of the Korea Society of Computer and Information
• /
• v.4 no.2
• /
• pp.27-38
• /
• 1999

This paper proposes a high speed digital neuron processor which uses the residue number system, making the high speed operation possible without carry propagation,. Consisting of the MAC(Multiplier and with Accumulator) operation unit, quotient operation unit and sigmoid function operation unit, the neuron processor is designed through 0.8$\mu$m CMOS fabrication. The result shows that the new implemented neuron processor can run at the speed of 19.2 nSec and the size can be reduced to 1/2 compared to the neuron processor implemented by the real number operation unit.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.8 no.3
• /
• pp.129-136
• /
• 2013

In this paper, a motion control system based on 2-axis gimbal system is designed and implemented to drive a high speed and precision. The proposed system consists of the RS-422 interface, 2-axis gimbal platform, servo control unit integrated with a high speed DSP chip-set, servo amplifier unit, potentiometer sensor unit, and resolver sensor unit. The servo control unit using the high speed DSP firmware is designed to get a fast response without an overshoot with step input and a RMS error of low probability with ramp input. The servo amplifier unit using a voltage control is designed to resolve the zero-crossing distortion for precise motion. To verify the performance and stability of the implemented system, experiments are performed through a measurement of the time and frequency domain response in a laboratory environment by using a PXI(PCI eXtentions for Instrumentation).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.06a
• /
• pp.478-479
• /
• 2009

The HEMU-400X(High-speed Electric Multiple Unit 400km/h eXperimental) project starts in 2007. It is required to analysis and simulate the train performance throughout the project life cycle for a successful completion of the project. This paper is devoted to the development of a train performance analysis model for the high-speed electric multiple unit 400km/h experimental. The model consist of running resistance model, train model, traction model and braking model. So, this paper represents the results of the train performance analysis.

• Proceedings of the KIEE Conference
• /
• 1990.11a
• /
• pp.439-442
• /
• 1990

A powerful general purpose image processing processor is developed using a high-speed DSP chip, TMS320C30. The image processing processor, compatible to the standard VME bus, is composed of VME bus interface unit, video rate image grabbing/coding unit, TMS320C30 interface unit and bank of high-speed SRAMs. The performance is evaluated experimentally with the general image processing algorithms and the results show that the developed processor is capable of high speed image processing.

• The Journal of Information Technology
• /
• v.4 no.3
• /
• pp.155-163
• /
• 2001

In this paper, we implemented sigmoid active function which make it difficult to design of the digital neuron networks. Therefore, we designed of the high speed processing of the sigmoid function in order to digital neural networks. we designed of the MAC(Multiplier and Accumulator) operation unit used residue number system without carry propagation for the high speed operation. we designed of MAC operation unit and sigmoid processing unit are proved that it could run of the high speed. On the simulation, the faster than 4.6ns on the each order, we expected that it adapted to the implementation of the high speed digital neural network.

• East Asian mathematical journal
• /
• v.26 no.1
• /
• pp.69-73
• /
• 2010

We invoke the characterization of Pythagorean-hodograph polynomial curves and prove that it is impossible to parameterize any real curves, other than a straight line, by rational functions of its arc length.

• Proceedings of the IEEK Conference
• /
• 2000.11a
• /
• pp.267-270
• /
• 2000

In this paper, we consider the simple redundant structures with the function of hardware based active/standby control. The system includes two switch modules. The switch module is connected to a data bus, but only the active switch module has control of the data bus. The standby unit takes over the function of the active unit when the active unit failure or mode command are asserted. And this paper illustrate the high-speed router system and the overall redundant system architecture. The proposed redundant architecture for 80G Router system is verified and implemented with experiment.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.11
• /
• pp.561-567
• /
• 2018

This study was carried out to improve the ride quality of high-speed electric multiple unit. Through dynamic analysis of the HEMU-430X, the range of the equivalent conicity with a critical speed of 300 km/h was between 0.05 and 0.25. The initial adopted wheel profile of HEMU-430X was S1002. The equivalent conicity of S1002 with the mileage of more than 40,000 km was about 0.033 and it was confirmed that XP55 is more suitable for stable operation because XP55 has the equivalent conicity of over 0.061. In order to improve ride quality of high-speed electric multiple unit, the change of installation angle of the yaw damper was suggested from $7.35^{\circ}$ to $0^{\circ}$. From sensitivity analysis and optimization, the air spring lateral and vertical stiffness was suggested to be reduced by 30% and the secondary vertical and lateral damper damping coefficient was increased by 50%. By applying this, it was expected that the car body acceleration could be improved by about 20% on average. The HEMU-430X's yaw damper installation angle was changed to $0^{\circ}$ and the damping coefficient of the lateral damper was increased by 30%. When the test run was carried out at the speed of 300 km/h on the Kyungbu high-speed line, the vehicle lateral acceleration had improved by 34.3%. The effect of additional improvement measures proposed in this paper will be tested in the on track test. The riding quality improvement process used in this study can be used to solve ride quality problems that can occur in commercial operation of high-speed electric multiple unit in the future.