• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1033-1040
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• 2004

Utilizing of the geotextile container shows several advantages such as standardized construction, factory manufactured products, the control of quality, workability. and economical point of view. Recently this technique can be applied to rehabilitate the loss of rail roadbed due to the heavy rainfall. In this study, a large-scale laboratory test were conducted with simulation of static performance on the geotextile container reinforced rail roadbed. Based on the laboratory test results, the vertical pressure distribution with respect to the depth, and settlement of rail roadbed were measured and compared test results between geotextile container reinforced case and unrein forced case. Thus, the effectiveness of reinforcement was evaluated in terms of its performance and stability.

• 한국수소및신에너지학회논문집
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• 제20권2호
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• pp.168-178
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• 2009

To check feasibility of SEWGS(Sorption Enhanced Water Gas Shift) system, conceptual design and sensitivity analysis of operating variables have been investigated based on a design program of two-interconnected fluidized bed. Based on the conceptual design results, the optimum configuration for SEWGS was considered. Among three configurations, bubbling beds system was selected as the best configuration. Process design results indicate that the SEWGS system is compact and feasible. Based on the selected operating conditions, the effects of variables such as pressure, $CO_2$ capture capacity, solid inventory, CO conversion and $CO_2$ capture efficiency have been investigated as well.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.187-194
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• 2010

Shape optimization of an upper plenum of PBMR type gas cooled nuclear reactor has been performed by using three-dimensional Reynolds-Averaged Navier-Stokes (RANS) analysis and surrogate modeling technique. The objective function is defined as a linear combination of uniformity of flow distribution in the core and pressure drop in the upper plenum and the core. The ratio of thickness of slot to diameter of rising channels, ratio of height of upper plenum to diameter of rising channels, and ratio of eight of the slot at inlet to outlet, are used as design variables for optimization. Design points are selected through Latin-hypercube sampling. The optimal point is determined through surrogate-based optimization method which uses 3-D RANS analyses at design points. The results show that the optimum shape represent remarkably improved performance in flow uniformity and friction loss than the reference shape.

• 한국전산유체공학회지
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• 제15권3호
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• pp.16-23
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• 2010

Shape optimization of an upper plenum of a PBMR type gas cooled nuclear reactor has been performed by using three-dimensional Reynolds-Averaged Navier-Stokes (RANS) analysis and surrogate modeling technique. The objective function is defined as a linear combination of uniformity of flow distribution in the core and pressure drop in the upper plenum and the core. The ratio of thickness of slot to diameter of rising channels, ratio of height of upper plenum to diameter of rising channels, and ratio of height of the slot at inlet to outlet, are used as design variables for optimization. Design points are selected through Latin-hypercube sampling. The optimal point is determined through surrogate-based optimization method which uses 3-D RANS analyses at design points. The results show that the optimum shape represent remarkably improved performance in flow uniformity and friction loss than the reference shape.

• 대한기계학회논문집
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• 제19권3호
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• pp.796-805
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• 1995

For the purpose of improving performances of a turbocharged diesel engine at low speed, this study investigates the effects of the injected air for the performances and flow characteristics in the intake and exhaust pipes by using the computer simulation with test bed. In the theoretical analysis, the whole flow system, including engine cylinders and intake and exhaust pipes, is calculated numerically by the method of filling and emptying. From the results of this study, the following conclusions may be summarized. Increasing injected air pressure into the pipe of compressor exit brings about the improvement in a performance and flow characteristics of intake and exhaust pipes under full load operating conditions at 1000 rpm of the engine speed, but shows trends of the inferior performances under no load operating conditions at 2000 rpm of the engine speed.

• Archives of Plastic Surgery
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• 제41권1호
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• pp.81-84
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• 2014

In this article, we present two cases of femoral pseudoaneurysm (PA) at the femoral arterial puncture site followed by necrotizing fasciitis, which is rare but can be fatal when not managed appropriately. PA was revealed by lower-extremity angiography and color-flow Doppler ultrasonography. Hematoma removal, thrombolysis, and bleeder ligation with Gelfoam were repeatedly performed by a vascular surgeon. When necrotizing fasciitis developed, aggressive surgical drainage and creation of a viable wound bed for reconstruction were mandatory. We adopted a vacuum-assisted closure device (Kinetics Concepts International) as the standard treatment for complicated, serious, infected PA of the puncture site. Excellent clinical outcomes were obtained.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.93-96
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• 2007

Catalytic activities of color and conductive carbon blacks in ethane decomposition for $CO_2-free$ hydrogen production were investigated. The ethane decomposition was carried out in a conventional fixed bed reactor under atmospheric pressure at 973-1173 K for 2 hours. When the decomposition in the presence of carbon black was compared with the non-catalytic thermal decomposition, the former exhibited significantly higher ethane conversion, higher C(s) selectivity and lower ethylene selectivity with small increase of the methane selectivity, which resulted in higher hydrogen yield. This indicates that carbon black is catalytically effective for dehydrogenation of ethane as well as subsequent decomposition of ethylene. All the carbon blacks exhibited stable catalytic activity with time. In durability tests, fluffy N-330 and BP2000 maintained their activities for 36 hours.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.429-432
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• 2007

Gasification has been regarded as a very important technology to decrease environmental pollution and to obtain higher efficiency, The coal gasification process converts carbon containing coal into a syngas, composed primarily of CO and $H_2$. And the coal syngas can be used as a source for power generation or chemical material production. This paper illustrates the operation characteristics and results of pilot-scale coal syngas production facilities. The entrained-bed pilot scale coal gasifier was operated normally in the temperature range of $1,300{\sim}1,400^{\cdot}C$, $2{\sim}3kg/cm^2$ pressure. And Indonesian KPC coal produced syngas that has a composition of $46{\sim}54$% CO, $20{\sim}26$% $H_2$, and $5{\sim}8$% $CO_2$.

• 대한기계학회논문집
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• 제19권7호
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• pp.1780-1786
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• 1995

The main goal of the present study is to establish the techniques and methodolgies of turbine performance test through evaluating the objective turbine test piece, and checking the reliability of the self-developed test facility by performing a series of turbine tests under ambient temperature condition. A high speed coupling, a lubrication system and a test bed of the test facility were modified through a series of preliminary test in order to reduce the vibration and oil leakage. The flowrate control of the test facility and data acquisition were accomplished by using a software called "Labview" The measurement of shaft horse power and control of rotational speed according to the conditions of turbine rotation were performed by a separate system. The preliminary evaluation of the measured data suggests that the developed test facility and the test technique can be used reliably for the performance test of turbines with the minor improvement.provement.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.489-492
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• 2002

We have performed batch chromatography experiments to calculate parameters which are used to design SMB chromatography system. Isotherms of S- and R-ketoprofen enantiomers were gained from small amount loading experiments in a column, and flow rate of four zones of SMB chromatography were calculated using mass balance equations. As a results, diameter and length of columns were 10mm and 600mm, and flow rate of each zone were as follows; $Q_{Feed}$=1.00ml/min ,$Q_{Elu}$=2.81ml/min ,$Q_{Raf}$=1.81ml/min ,$Q_{Ext}$=2.00ml/min , and $Q_{Rec}^{TMB}$=10.75ml/min , From the Darcy's equation, the pressure drop in whole columns of SMB chromatography was 128bar.