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Yang, Hee-Sung;Park, Byung-Hoon;Yoon, Woong-Sup
- Journal of the Korean Society for Aeronautical & Space Sciences
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- v.35 no.9
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- pp.805-815
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- 2007
In order to build a conceptual design program for a liquid rocket engine system, performance based sub-programs for each core component of the engine system were made. Parts included were the combustion chamber, supersonic nozzle, centrifugal pump, and impulsive turbine. Simple mathematical models based on classical thermodynamic and inviscid theories were adopted with proper tuning by empirical data. In Part I, aiming to validate each sub-program, we examined the results of each program qualitatively, and parametrically investigated the sensitivity due to the change in design parameters.
https://doi.org/10.5139/JKSAS.2007.35.9.805 인용 PDF KSCI

Kim, Young-Jin;Han, Moo-Young
- Proceedings of the Korea Water Resources Association Conference
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- 2008.05a
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- pp.495-499
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- 2008
This study developed a determination method for a rainwater retention-pumping combination system for roof runoff control. The outflow and stored water volume in the rainwater system was simulated using a water balance equation. Its result is presented in the TPP (Tank capcity-Peak outflow-Pumping rate) curves for rainfall return periods. In a case study on reduction of the peak flow rate of 100-year return period to 5-year in Seoul, The range of pumping rate for $100m^2$ roof area is determined as $0{\sim}25{\ell}$/min. Additionally, retention volume of $8.5{\sim}10m^3$ can be combined with the pumping rate range. That is to say an effective combination of a retention-pumping system capacity can be determined from a system of $8.5m^3$ tank with $25{\ell}$/min to $10m^3$ tank without pump. Using the TPP curves, engineers can determine the effective combination range of retention & pumping system capacity. Furthermore, that can be helpful to decide a detail system capacity for field condition.
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Lim, Gyu-Ho;Song, Sung-Young;Park, Jeong-Hun;Li, Long-Zhen;Lee, Cheon-Hyo;Lee, Tae-Yeong;Cho, Gyu-Sam;Park, Mu-Hun;Ha, Pan-Bong;Kim, Young-Hee
- Journal of the Korea Institute of Information and Communication Engineering
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- v.11 no.10
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- pp.1899-1909
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- 2007
A cross-coupled charge pump with internal pumping capacitor, witch is advantages from a point of minimizing TFT-LCD driver IC module, is newly proposed in this paper. By using a NMOS and a PMOS diode connected to boosting node from VIN node, the pumping node is precharged to the same value each pumping node at start pumping operation. Since the lust-stage charge pump is designed differently from the other stage pumps, a back current of pumped charge from charge pumping node to input stage is prevented. As a pumping clock driver is located the font side of pumping capacitor, the driving capacity is improved by reducing a voltage drop of the pumping clock line from parasitic resistor. Finally, a layout area is decreased more compared with conventional cross-coupled charge pump by using a stack-MIM capacitors. A proposed charge pump for TFT-LCD driver IC is designed with $0.13{\mu}m$ triple-well DDI process, fabricated, and tested.
https://doi.org/10.6109/jkiice.2007.11.10.1899 인용 PDF KSCI