• 한국자동차공학회논문집
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• 제16권1호
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• pp.127-133
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• 2008

Since the 1960's, exhaust gas recirculation(EGR) has been used effectively in spark ignition(SI) engines to control the exhaust emissions of the oxides of nitrogen(NOx). The most important requirements for the application of EGR systems to conventional SI engines are controllable flow rate and good dynamic response. In order to evaluate the characteristics of the electronic EGR valve, a test bench which is consisted of blower, heater, air flow meter and driving unit for electronic EGR valve was set up to simulate engine operating conditions. During the tests, the valve actuation parameters were controlled and the valve lifts and flow rates were measured to infer the characteristics of EGR valve. The results confirmed the capabilities of mathematical analysis and it seems that the correction for the valve lift and potentiometer output is necessary to achieve precise control of EGR rates.

• 한국농공학회지
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• 제37권3_4호
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• pp.48-60
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• 1995

A flood - flow forecasting system model of river basins has been developed in this study. The system model consists of the data management system(the observation and telemetering system, the rainfall forecasting and data-bank system), the flood runoff simulation system, the reservoir operation simulation system, the flood forecasting simulation system, the flood warning system and the user's menu system. The Multivariate Rainfall Forecasting model, Meteorological factor regression model and Zone expected rainfall model for rainfall forecasting and the Streamflow synthesis and reservoir regulation(SSARR) model for flood runoff simulation have been adopted for the development of a new system model for flood - flow forecasting. These models are calibrated to determine the optimal parameters on the basis of observed rainfall, 7 streamfiow and other hydrological data during the past flood periods.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
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• pp.195-198
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• 2001

We developed the portable blood analysis system, which can be measured pH of the blood. This system is composed to electronic circuit, mechanism, and system software. Electronic circuit is composed to the sensor, pre-amp part, temperature regulation part, fluid sensing part, A/D(analog to digital) conversion part, main and peripheral device processing part. And the mechanism is composed to the flow cell and the liquid flow part. The liquid flow part is consisted of blood and washing control system under the control of the 6-channel solenoid valve and syringe rump. The system software is composed to measurement program, calibration program, washing and diagnostic program. The program of each routine is designed as sequential process for an efficiency. And the portable pH analysis system used two-point calibration method using the two types of corrective liquid. As a result, we obtained the calibration curve and calculated the value of pH. For verifying the system, we confirmed the output voltage of the sensor, and estimated reappearance of system using the standard liquid.

• 토지주택연구
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• 제11권1호
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• pp.59-66
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• 2020

This thesis investigates relationship between Stock-to-Flow price and housing starts in Seoul metropolitan form 2008 year to 2019 year. The paper tests the relationship through two time-series models such as a vector error correction model and Dynamic Panel regression model. The model results show evidence of positive correlation between Stock-to-Flow price and housing starts in the long run. By transforming the regional data into a panel data set and running a fixed effects model, we test the explanatory power of PBR on housing starts. The result of VECM confirms that one unit uprising PBR raises up apartment construction by 7.4%. This result supports that PBR is a major factor in choosing a start of housing construct. Base on the result of empirical model, We also suggest that the market self-regulation function of housing providers is operating in the entire metropolitan area market.

• 한국전산구조공학회논문집
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• 제24권4호
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• pp.399-404
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• 2011

과적차량은 도로관련 사회간접자본과 국가 경제적 측면, 교통류, 도로안전 등 다양한 측면에서 악영향을 미치고 있다. 이에 따라, 본 논문에서는 지능형 과적차량 단속시스템 개발을 위하여 유비쿼터스 센서네트워크(USN) 시스템을 구성하였다. 그리고 WIM(Weight-in-motion) 시스템과 달리 도로자체의 변형을 측정하여 주행중인 차량의 축을 감지한 후, 도로 하면에 부착된 변형률센서를 통하여 얻은 신호와 해석방법을 이용하여 차량의 중량을 계산하는 방안을 제시하였다. 또한 유전자알고리즘 기법의 차량하중 분석방법을 위한 시뮬레이션 실험을 실시하였고, USN구성을 위한 센서의 무선화 테스트를 실시하였다.

• 대한한의학원전학회지
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• 제28권1호
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• pp.143-150
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• 2015

Objectives : This study aim to find out the reason why perspiration related with the Heart in Korean Medicine. Results : Perspiration is closely connected with the Heart because sweat is a kind of ultrafiltrate of the blood and the Heart conducts blood. In order to perspire, it is necessary to increase blood flow to capillary surrounding sweat glands. The Heart plays an important role in increasing blood flow to capillary surrounding sweat glands. Perspiration controls the body temperature. It must be increase the blood flow to skin in order that down the high body temperature. The Heart plays an important role in increasing blood flow. Conclusions : Perspiration is closely connected with the Heart because sweat is a kind of ultrafiltrate of the blood and there are plenty capillary surround sweat gland. The Heart controls the blood flow to skin in order to regulate of body temperature.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1383-1388
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• 2007

Recently, the semiconductor and display industries have tried to reduce the emissions of perfluorocompounds (PFCs) from the globally environmental regulation. Total amount of PFC emission can be calculated from the flow rate and the partial pressures of PFCs. For the precise measurement of PFC emission amount, the mass flow controlled helium gas was continuously injected into the equipment of which scrubber efficiency is being measured. The partial pressures of PFCs and helium were accurately measured using a mass spectrometer in each sample extracted from inlet and outlet of the scrubber system. The flow rates are calculated from the partial pressures of helium and also, PFC destruction and removal efficiency (DRE) of the scrubber is calculated from the partial pressure of PFC and the flow rate. Under this method, the relative expanded uncertainties of the flow rate and the partial pressures of PFCs are ± 2% (k = 2) in case the concentrations of NF3 and SF6 are as low as 100 μmol/mol.

• 농업과학연구
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• 제46권3호
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• pp.549-557
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• 2019

Staphylococcal enterotoxin is a very common cause of food poisoning. Conventional detection methods for the toxin including enzyme-linked immunosorbent assays (ELISAs), chemiluminescence (ECL), and polymerase chain reaction (PCR) assays require a lot of time, efforts, and expert technicians. Lateral flow strip kits have shown great potential for the rapid detection of foodborne pathogens. The lateral flow strip kit is widely used in clinical settings because it is easy to use, fast, and cost effective. A typical lateral flow strip kit uses colloidal gold to generate a visual signal. However, the lateral flow strip kit based on colloidal gold has limited sensitivity to fulfill food safety regulation requirements. This study was performed to develop a rapid test kit for pathogenic staphylococcal enterotoxin B (SEB) in food samples. The rapid detection kit was fabricated based on a nitrocellulose lateral-flow strip. Cellulose nano beads and SEB antibodies were used as the tag and receptor, respectively, to improve the detection performance. Manually spotted SEB antibody and anti-rabbit antibody on the surface of the nitrocellulose membrane were used as test and control spots, respectively. The feasibility of the rapid test kit to detect SEB in samples was evaluated. The sensitivity of the kit was 10 ng/mL SEB spiked in PBS. Additionally, the rapid test kit could detect 1 ng/mL of SEB in chicken meat extract.

• Journal of Advanced Marine Engineering and Technology
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• 제36권4호
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• pp.423-429
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• 2012

밀러 사이클은 저배기 및 고효율 달성으로 Tier II 규제뿐만 아니라 $CO_2$ 저감을 동시에 달성할 수 있는 기술로 알려져 있다. 그러나 이를 위해서는 충분한 흡입공기량이 확보되어야 하며 흡기계통은 공기저항을 최소화할 수 있는 형상으로 개선되어야 한다. 본 연구에서 흡기계통 설계 및 사이클 해석에 활용하기 위한 기초 자료 확보를 위해 흡기밸브의 유량계수를 측정하였다. 유량계수 측정에는 정상유동장치를 이용하였다. 중속 박용기관에 사용되는 포핏 밸브를 대상으로 실험을 수행한 결과, 흡기밸브 유량계수는 밸브양정의 증가에 따라 약 0.62까지 지속적으로 증가하는 경향이며 행정/보어 비와는 무관한 흡기밸브 고유의 특성이 있음을 확인하였다.

• The Korean Journal of Pain
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• 제9권1호
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• pp.57-62
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• 1996

Stellate ganglion block(SGB) improves cutaneous blood flow of the head and neck region and upper extremity. For this reason, SGB has been performed in neural and circulatory disorders. But there is controversy on the cerebral blood flow regulation by sympathetic innervation. We investigated the hypothesis that cerebral blood flow could be affected by blocking ipsilateral sympathetic innervation of cerebral blood flow could be affected by blocking ipsilateral sympathetic innervation of cerebral vasculature. In 10 volunteers, the blood flow velocity and pulsatility index(PI) of middle cerebral artery(MCA) was measured using Transcranial Doppler Flowmeter, before and 15 minutes after SGB, at block side and opposite side. The blood flow velocity of MCA at block side was increased from $62.60{\pm}7.60$ cm/s to $72.80{\pm}8.01$ cm/s(P<0.01) and the PI at block side decreased from $0.75{\pm}0.12$ to $0.60{\pm}0.11$(P<0.05). But the blood flow velocity and PI at opposite side did not change. This study demonstrated that the cerebral blood flow could be increased by SGB, the preganglionic nerve fibers of which synapse with other cervical sympathetic ganglions.