• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.1
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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.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.3_4
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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.

• Proceedings of the IEEK Conference
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• 2001.06e
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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.

• Land and Housing Review
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• v.11 no.1
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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.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.4
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• pp.399-404
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• 2011

Overload vehicles have demoralizing influence upon the social overhead capital, economics of nation, traffic flow and road safe as various components. Accordingly, this study established a ubiquitous sensor network system to develop an intelligent regulation system to monitor overloaded vehicles in motion. and Unlike WIM, after detecting the axle of driving vehicles by measuring deformation of roads, this system calculates the weights of vehicles by using signals from the strain sensors installed under the road and an analysis method. Also the study conducted an simulation test for vehicle load analysis using genetic algorithm. and tested wireless sensor for USN system.

• Journal of Korean Medical classics
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• v.28 no.1
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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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• v.28 no.8
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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.

• Korean Journal of Agricultural Science
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• v.46 no.3
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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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• v.36 no.4
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• pp.423-429
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• 2012

Miller cycle is considered as an effective means to meet the regulation on Tier II and to reduce $CO_2$ emission. For this cycle, the amount of intake air supplied should be enough increased. Therefore, the intake system with minimized resistance for air flow is under consideration. In this study, the flow coefficients of intake valves were measured in order to obtain the basic data for the cycle simulation and intake port design. The flow coefficients were measured using the steady-flow test rig. As a test result for the poppet valve used the marine engine with medium speed, the flow coefficients are increased to about 0.62 with the valve lift. In addition it is confirmed that the flow coefficients have the characteristic value irrelevant to the S/B ratio.

• The Korean Journal of Pain
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• v.9 no.1
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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.