• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.264-268
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• 2006

혈당강하 요구르트의 개발을 위해 Streptococcus salivarius subsp. thermophilus와 Lacto-bacillus acidophilus 145, Bifidobacterium infantis 혼합균주에 사균인 FK-23 유산구균, 피니톨, 식이섬유, 백강낭콩 추출 분말, 에리스리톨, 바나바 추출물 등의 기능성 성분을 포함한 요구르트를 제조하여 정상인과 혈당치가 높은 당뇨 환자를 대상으로 간이 임상시험을 실시하였다. 1. 정상인의 식후 혈당치는 일반 요구르트를 섭취했을 때보다 혈당 강하 요구르트 음용시 더 낮게 측정되었으며 임상대상자 대부분에서 동일한 현상이 나타났다. 2. 혈당치가 높은 당뇨환자 10명을 대상으로 식후 혈당치 변화 및 음용기간 중 혈당치 변화를 확인한 결과 혈당 강하 요구르트를 음용하기 전보다 음용 후 혈당치가 식후 30 당증가 억제율도 임상대상자의 80%가 감소하는 효과를 나타냈다. 3. 30일간 혈당 강하 요구르트를 음용한 후 식후 혈당치의 변화를 확인한 결과 음용전보다 음용 후 120분 경과 때, 혈당치가 59 mg/dL 감소하였으며 음용기간이 증가할수록 지속적으로 감소하는 경향을 나타내었다.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.2
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• pp.76-86
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• 1999

It is necessary to estimate the groundwater recharge rate properly to predict the demand of groundwater and to establish the plan for the development of groundwater in the future. In this paper, A small basin in Chojung area is selected to calculate the groundwater recharge rate. In the calculation, water balance analysis, SCS-CN (Soil Conservation Service-Curve Number) method. groundwater-level analysis and hydrograph of outflow analysis are applied to this area. Data of precipitation measured by Chungju climatological station for about 10 years are used for water balance analysis and SCS-CN method. For the groundwater-level analysis. variations of groundwater-level measured from the 3 test wells in 1997's are used and stage-discharge rating curves in this area for 3 years are used for the hydrograph of outflow. The recharge rate calculated by water balance is 19%, 12.95% by SCS-CN method. 16.51% by groundwater-level analysis and 10.9% by hydrograph of outflow analysis and the overall average recharge rate is about 14.84%.

• Transactions of the Korean hydrogen and new energy society
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• v.6 no.2
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• pp.53-63
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• 1995

A 100kW class stack consisting of 10 molten carbonate fuel cells has been fabricated. Internally manifold stack has been tested for endurance. Each cell in the stack had an electrode area of $100cm^2$ and reactant gases were distributed in each cells in a cross-flow configuration. Initial and long term operation performance of the stack was investgated as a function of gas utilization using a specially designed small scale stack test facility. It was possible to have a stack with an output of more than 100W using an anode gas of 72% $H_2/18%$ $CO_2/10%H_2O$ and cathode gas of 33% $O_2/67%$ $CO_2$ and 70% Air 30% $CO_2$. The output and voltage of the stack at a current 15A($150mA/cm^2$) and gas utilization of 0.4 showed 125.8W and 8.39V respectively by elapsed time of 310 hours operation. In long term operation characteristics, the voltage drop of 52.4mV/1000hour was observed after more than 1,840 hours operation. Among the voltage drop, the OCV loss was highest than other voltage loss such as internal resistance and electrode polarization. Non uniformity of 2voltages and degradation of cell voltage in the stack was observed in according to changing the utilization rate after a long term operation. Further work for increasing the performance prolonging the life of the stack are required.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.8
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• pp.759-765
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• 2013

This study proposes the characteristics of the pressure drop in a compressible fluid through porous media for application to a porous injector in a liquid rocket engine in order to improve the uniformity of the drop size distribution and the mixing performance of shear coaxial injectors. The fluid through the porous media is a Non-Darcy flow that shows a Nonlinear relation between the pressure drop and the velocity at high speed and high mass flow rate. The pressure drop of the Non-Darcy flow can be derived using the Forchheimer equation that includes the losses of viscous and inertia resistance. The permeability and Ergun coefficient represented as a function of the pressure drop and pore size can be applied to the porous injector, where the fluid through the porous media is compressible. A generalized correlation between the pressure drop in relation to the pore size was derived.

• Membrane Journal
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• v.6 no.2
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• pp.86-95
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• 1996

Rotary disc ultrafiltration module(RDM) was developed for the separation of oil e$$\mu$sions. This module was devised to reduce the gel polarization phenomenon by decoupling the operation pressure and the surface velocity of solution in ultrafiltration(UF) processes. The rotary disc membrane consists of 3mm-thick ABS plate covered with UF membrane (UOP, U.S.A.). When the angular velocity($\omega$) was increased, the pure water flux was slightly decreased due to pressure drop caused by centrifugal force and slip flow at the surface of membrane. The pressure drop was proportional to the square of linear velocity(${\omega}r$). When the angular velocity was changed from 52.36rad/s to 2.62rad/s, the flux decline for 5% cutting oil in one-shaft RDM at $25^{\circ}C$ and 0.1MPa was 30.16%. In the lower concentrations, angular velocity tends to give less effect on the flux. Flux(J; $kg/m^{2} \cdot s$) in a rotating disc module is mainly a function of the bulk concentration($C_{B}$; %), the linear velocity(${\omega}r$; m/s) and the effective transmembrane pressure($\Delta P_{T}$ ; Pa). Using a modified resistance-in-series model, the flux data of cutting oil experiments were fitted to give the following equation.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.437-440
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• 2005

In the present work, characteristics of the flow in CAGE of a steam turbine LP/HP Bypass control valve for thermal power plant are investigated. The flow field is analyzed numerically by solving steady three-dimensional Reynolds-averaged Navier-Stokes equations. Shear stress transport (SST) model is used as turbulence closure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.4
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• pp.1-8
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• 1985

Stability analysis of the embankment as to water level varation is the most important problem in the safety of the slope because the stress of embankment inside varies as to drawdown of seepage line. Especially when the water level is rapidly drawdown, because the flow direction of the free surface changes the toe of embankment, the factor of safety comes to small, therefore the embankment is dangered. For the purpose of studing these phenomena, the experimental models are built with sand in the laboratory. In the experimental consideration, the falling seepage line and the shape of failure are measured. This paper intends to study the failure slip surface, the relationship between the factor of safety and drawdown velocity, and hydraulic gradient. The results of the experimental study are summarized as follows; 1. Owing to the drawdown of free surface, sliding failure occurred in the upstream fill, the height of failure is 5~10, 9~15, and 13~21(cm) in each model. 2. In consideration of the distribution of pore water pressure Table-5 shows each factor of safety. In the relationship between the drawdown velocity and the factor of factor it's velocity should be limited to 0.21~0.28 (cm/sec), according to each models. In the relationship between the factor of safety and the hydraulic gradient within the upstream slope, it's gradient must be below 0.36~0.43.

• Radiation Oncology Journal
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• v.25 no.1
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• pp.34-42
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• 2007

[ $\underline{Purpose}$ ]: We performed a retrospective non-randomized clinical study of locally advanced rectal cancer, to evaluate the anal sphincter preservation rates, down staging rates and survival rates of preoperative chemoradiotherapy. $\underline{Materials\;and\;Methods}$: From January 2002 to December 2005, patients with pathologically confirmed rectal cancer with clinical stage T2 or higher, or patients with lymph node metastasis were enrolled in this study. A preoperative staging work-up was conducted in 36 patients. All patients were treated with preoperative chemoradiotherapy, and curative resection was performed for 26 patients at Hallym University Sacred Heart Hospital. Radiotherapy treatment planning was conducted with the use of planning CT for all patients. A total dose of $45.0{\sim}52.2\;Gy$ conventionally fractionated three-dimensional radiotherapy was delivered to the whole pelvis. Chemotherapy was given at the first and fifth week of radiation therapy with continuous infusion i.v. 5-FU (Fluorouracil) and LV (Leucovorine). Surgical resection was performed 2 to 4 weeks after the completion of the chemoradiotherapy regimen. $\underline{Results}$: The complete resection rate with negative resection margin was 100% (26/26). However, a pathologically complete response was not seen after curative resection. Surgery was done by LAR (low anterior resection) in 23 patients and APR (abdomino-perineal resection) in 3 patients. The sphincter preservation rate was 88.5% (23/26), down staging of the tumor occurred in 12 patients (46.2%) and down-sizing of the tumor occurred in 19 patients (73%). Local recurrence after surgical resection developed in 1 patient, and distant metastasis developed in 3 patients. The local recurrence free survival rate, distant metastasis free survival rate, and progression free survival rate were 96.7%, 87% and 83.1%, respectively. Treatment related toxicity was minimal except for one grade 3, one grade 4 anemia, one grade 3 leukopenia, and one grade 3 ileus. $\underline{Conclusion}$: Preoperative concurrent chmoradiotherapy for locally advanced rectal cancer seems to have some potential benefits: high sphincter preservation and down staging. Treatment related toxicity was minimal and a high compliance with treatment was seen in this study. Further long-term follow-up with a larger group of patients is required.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.105-109
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• 2004

우리나라 지형의 특성은 약 70%가 산으로 이루어져 있다. 이러한 지형적 여건은 교통과 관련된 사회간접 자본의 증가로 이어지며, 최근에는 산업의 발전에 힘입어 교통량의 증가와 물류비용의 절감을 목적으로 철도 및 도로의 건설시 터널의 계획 및 시공이 증가되고 있는 추세이다. 이에 따라 터널의 환경개선과 화재시 제연을 목적으로 설치되는 제트팬(Jet Fan)의 용량이 차지하는 전기적 비중이 높아지고, 전압강하에 대한 손실율이 증가되고 있다. 따라서 제트팬의 설치시 배치방법과 터널의 길이에 따른 전기실 배치를 Case 별로 분류하여 전압강하를 계산하고 분석하여 가장 효율적이며 경제적인 방안을 연구하고 정리하여 향후 설계시 기초자료를 제공하고자 하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.116-121
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• 2006

The pressurization system in a liquid rocket propulsion system provides a controlled gas pressure in the ullage space of the vehicle propellant tanks. It is advantage to employ a hot gas heat exchanger in the pressurization system to increase the specific volume of the pressurant and thereby reduce over-all system weight. Therefore a significant improvement in pressurization system performance can be achieved, particularly in a cryogenic system. For this study air and $CN_2$ are employed as external fluid and pressurant respectively Numerical analysis on the pressurant discharging characteristics have been compared with the experimental results performed at the PTF(Propellant-feeding Test Facility). It is shown that the discrepancy of analytic and experimental results is within about ${\pm}15%$. It is estimated that the temperature drop rate of cryogenic pressurant immersed liquid oxygen can be predicted using this analytic approach method.