• Proceedings of the IEEK Conference
• /
• 2000.06b
• /
• pp.221-225
• /
• 2000

We designed asynchronous event logic library with 0.25$\mu\textrm{m}$ CMOS technology and interface chip for heterogeneous system with high-speed asynchronous FIFO operating at 1.6㎓. Optimized asynchronous standard cell layouts and Verilog models are designed for top-down design methodology. A method for mitigating a design bottleneck when it comes to tolerate clock skew is described. This communication scheme using clock control circuits, which is used for the free of synchronization failures, is analyzed and implemented. With clock control circuit and FIFO, high-speed communication between synchronous modules operating at different clock frequencies or with asynchronous modules is performed. The core size of implemented high-speed 32bit-interface chip for heterogeneous system is about 1.1mm ${\times}$ 1.1mm.

• Proceedings of the IEEK Conference
• /
• 2005.11a
• /
• pp.699-702
• /
• 2005

This paper describes a high speed interface using redundant multi-valued logic for high speed communication ICs. This circuit is composed of encoding circuit and decoding circuit. Because of the multi-valued data conversion, this circuit makes it possible to achieve higher operating speeds than that of a conventional binary logic. Using this logic, a 1:4 DEMUX (demultiplexer) was designed using a 0.35um standard CMOS technology. Proposed circuit is achieved an operating speed of 4.5Gb/s with a supply voltage of 3.3V and with power consumption of 53mW.

• Journal of Energy Engineering
• /
• v.22 no.2
• /
• pp.205-210
• /
• 2013

Cycle-to-cycle variation has long been recognized as limiting the range of operating conditions of spark ignition engines, in particular, under lean and highly diluted operation conditions. At a part load, some of the cycles tend to knock, while others may have incomplete combustion by the time the exhaust valve opens. An experimental study has been performed in order to evaluate the relative contribution of several relevant parameters on the cyclic variability in spark ignition engines. In general, the stability of engine operation is improved with fuel injector according to the optimal injection timing, but the stability of engine operation at idle is not improved compared with a practical gasoline engine. In this study, we investigated the relationship of the effect of operating conditions for the stability at low speed and load.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.22 no.7
• /
• pp.642-649
• /
• 2012

This paper deals with a copper die casting induction motor which has several advantages of motor performance. The developed motor is used as spindle motor in machining center. The dynamic characteristic analysis of rotor is dealt with for precision machining. The critical speed of rotor considering rotation and gyroscopic effect should be above operating speed, 18,000 rpm, and have a 201 % sufficient separation margin. Also, the 3-D unbalance vibration response analysis is performed and enabled the prediction of the expected vibration amplitude by unbalance in high speed. The unbalance vibration responses of each position on the rotor are satisfied with allowable vibration displacement of API 611 standard according to balancing G grade(G 0.4, G 2.5, G 6.3). Copper die casting high speed induction motor is successfully developed and verified by experiment.

• Journal of Korean Association for Spatial Structures
• /
• v.5 no.1 s.15
• /
• pp.65-71
• /
• 2005

This research analyzed dynamic responses of the preflex railroad bridge. Vertical deflection and acceleration induced by operating train loads and test train loads were measured. Deflection of bridge by train traveling satisfies deflection limitation regulation (L/800) about the concrete bridge, but compare with UIC standard, vibration acceleration happened fairly greatly. Also test result show that acceleration receives greatly effect about the speed than deflection. It must discuss about vibration acceleration problems for speed elevation hereafter.

• Proceedings of the KSR Conference
• /
• 2004.10a
• /
• pp.1021-1027
• /
• 2004

This research analyzed dynamic responses of the preflex railroad bridge. Vertical deflection and acceleration induced by operating train loads and test train loads were measured. Deflection of bridge by train traveling satisfies deflection limitation regulation (L/800) about the concrete bridge, but compare with UIC standard, vibration acceleration happened fairly greatly. Also test result show that acceleration receives greatly effect about the speed than deflection. It must discuss about vibration acceleration problems for speed elevation hereafter.

• Journal of Power Electronics
• /
• v.8 no.3
• /
• pp.268-274
• /
• 2008

This paper presents a proposed position controller for a vector controlled induction motor. The position controller design depends on the rotational motion equations and a classical speed controller (CSC) performance. The CSC is designed to have the ability to track variable reference inputs and to provide a predefined system performance. Standard position controller in industry is presented to analyze its performance and its drawbacks. Then the proposed position controller is designed, based on the well defined rotational motion equations. The proposed position controller and the CSC are applied to control the position and speed of the vector controlled induction motor with different ratings. Simulation results at different operating conditions are presented to evaluate the proposed controllers' performance. The results show that the CSC can drive the motor with a predefined speed performance and can track a variable reference speed with an approximately zero steady state error. The results also show that the proposed position controller has the ability to effect high-precision positioning in a limited time and to track a variable reference position with a zero steady state error.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.245-250
• /
• 2006

From the research which it sees the safety regarding a high-speed railway vehicle collision and a derailment evaluation research it an example and executed. Japan, France, Germany and Spain, Italy and with our country together it compared a high-speed railway vehicle collision of the high-speed railroad operating nation and derailed relation safety standard and safety against the evaluation system trade name comparison it analyzed. The research which it sees it led and the accident instance against the hazard analysis against the collision and a derailment of the high-speed railway vehicle and a risk evaluation together and a high-speed vehicle collision and derailed it cannot prevention plan from hereafter domestic comparison it analyzed forecast it presented.

• Proceedings of the KSR Conference
• /
• 2004.06a
• /
• pp.675-678
• /
• 2004

Comparative analysis it did the interior noise of the KTX vehicle and the P-P Semaeul vehicle from the conventional line Homan Seodaejeon-Hanam section from the research which it sees. The test result KTX vehicle appeared when the P-P Semaeul vehicle compared to 20 - 25 KM/H speed up operating commerce operation speed even, the standard values 66 dBA the lowers 55 - 62 dBA. P-P Semaeul vehicle interior noise of the identical test section 63 dBA it will compare and there is a possibility the KTX vehicle knowing from the existing line operating hour interior noise.

• Proceedings of the KSR Conference
• /
• 2002.05a
• /
• pp.220-227
• /
• 2002

Now, Korea National Railroad is planning many ways to increase the maximum operating speed of train up to 200km/h by 2010. Among those ways, connecting conventional line with the KTX is the strongest alternative. Mostly, conventional lines are consisting of both KS50N and KS6O rail. However, the excessive abrasion might be occurred between wheel and rail when the KTX designed to operate on UIC60 is operating on the conventional line. On this study, new standard of 60kg-class rail considered suitability for both KTX and wheel used in conventional line is presented. It seems to be an effective solution for increasing maintenance costs expected when commercial speed of conventional line is increasing.