• Journal of Advanced Marine Engineering and Technology
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• v.25 no.1
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• pp.115-123
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• 2001

This study describes the combustion characteristics under various condition of air excess ratio and ignition timing in a 2-valve gasoline optically accessible engine with swirl control valve(SCV). It adapted three different types of SCA(open ration 72.5%, 78%, 89%) to strengthen a swirl flow. Pressure data were acquired using pressure sensor to investigate the effect of swirl flow on combustion, and from these pressure data, IMEP(indicated mean effective pressure) and MFB(mass fraction burnt)were calculated to explain burn rate and flame speed. From acquired flame images, inspected the flame propagation direction, flame area, and flame centroid, Flame propagation direction was shown different tendency between with/without SCV, and flame area with SCV was faster and larger than that of conventional engine. Finally, the representative flame image at each crank angle were acquired by PDF method to verify flame growth process. It is found that strengthened swirl flow is more beneficial for faster and stable combustion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.72-73
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• 2018

The accuracy of contingency estimation plays an important role for dealing with the uncertainty of the financial success of construction project. Its' estimation may be used for various purposes such as schedule control, emergency resolve, and quality expense, etc. This paper presents a contingency estimation method which is schedule control specific. The method 1) implements stochastic EVMS, 2) detects a specific timing for schedule compression, 3) identifies an optimal strategy for shortening planned schedule, 4) finds a probability density function (PDF) of project cost overrun, and 5) estimates the optimal contingency cost based on the level of confidence. The method facilitates expeditious decisions involved in project budgeting. The validity of the method is confirmed by performing test case.

• Journal of the Korean Society of Combustion
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• v.5 no.2
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• pp.1-8
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• 2000

The flamelet concept has been widely applied to numerically simulate complex phenomena occurred in nonpremixed turbulent flames last two decades, and recently broadened successfully the applicable capabilities to various combustion problems from simple laboratory flames to gas turbine engine, diesel spray combustion and partially premixed flames. The paper is focused on brief review of recently noticeable work related to flamelet modeling, which includes Lagrangian flamelet approach, RIF concept as well as steady flamelet approach. The limitation of steady flamelet assumption, the effect of transient behavior of flamelets, and the effect of spray vaporization on PDF model have been discussed.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.1 no.1
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• pp.213-230
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• 1995

The present work was done to investigate the pharmacological effectiveness of Guichoolpajing-Tang and Gamiguichoolpajing-Tang. The extracted water of those two prescription were administered to experimintal animals and determined analgesic, anti-pyretic, anti-inflammatory effects and effects on intravascular coagulation, spontaneous morements of the isolated rat uterus, the uterine contracion induced by oxytocin or $PGF_{20}$, lifespan of mice implanted intraperitoneally with Sarcoma 180. The following results were obtained. 1) The extracted water of Guichoolpajing-Tang and Gamiguichoolpajing-Tang were revealed significant analgesic effect. 2) The extracted water of Guichoolpajing-Tang and Gamiguichoolpajing-Tang showed anti-pyretic effect. 3) The extracted water of Guichoolpajing-tang and Gamiguichoolpajing-Tang showed anti-inflammatory effect. Especially, the extracted water of Gamiguichoolpajing-Tang showed more significant dffect than another. 4) Concerning the degree of concentration of FDP, Gamiguichoolpajing-Tang treated groups tevealed significant decreases. 5) The extracted water of both prescriptions revealed uterus relaxation on the spontaneous movement of the isolated rat uterus and showed uterine contraction induced by oxytocin or $PDF_{2}$. Especially Guichoolpajing-Tang showed more significant effect than another. 6) The extracted water of both prescription both prescriptions showed effect on lifespan of mice implanted intraperitoneally with Sarcoma 180.

• The Plant Pathology Journal
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• v.22 no.4
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• pp.360-363
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• 2006

Efficacy of plant growth promoting rhizobacteria(PGPR) Bacillus vallismortis strain EXTN-1 has been proved in eliciting induced systemic resistance(ISR) in several crops. The present paper described the beneficial effects of EXTN-1 in potato as increase in yield and chlorophyll content, and plant protection against Potato Virus Y and X(PVY & PVX). EXTN-1 induced systemic resistance to the plants resulting in significant disease suppression in the field. Also the plants under treatment with EXTN-1 had higher chlorophyll content. The bacterized plants had significantly higher yields over the untreated control plants. The strain induced activation of defense genes, PR-1a and PDF 1.2 in transgenic tobacco model, which indicated the possible role of both SA, and JA pathways in EXTN-1 mediated plant protection against crop diseases.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.1
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• pp.107-113
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• 2017

This paper provides a new approach for modeling of vector quantizer(VQ) followed by analysis and design of subband codecs with imbedded VQ's. We compute the mean squared reconstruction error(MSE) which depend on N the number of entries in each codebook, k the length of each codeword, and on the filter bank(FB) coefficients in subband codecs. We show that the optimum M-band filter bank structure in presence of pdf-optimized vector quantizer can be designed by a suitable choice of equivalent scalar quantizer parameters. Specific design examples have been developed for two different classes of filter banks, paraunitary and the biorthogonal FB and the 2 channel case. These theoretical results are confirmed by Monte Carlo simulation.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.1
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• pp.118-123
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• 2015

There have been various studies on measurements of flood risk and forecasting models. For river and dam region, PDF and FVI has been proposed for measurement of flood risk and regression models have been applied for forecasting model. For Bo region unlikely river or dam region, flood risk would unexpectedly increase due to outgoing water to keep water amount under the designated risk level even the drain system could hardly manage the water amount. GFI and general linear model was proposed for flood risk measurement and forecasting model. In this paper, FVI with the consideration of duration on GFI was proposed for flood risk measurement at Bo region. General linear model was applied to the empirical data from Bo region of Nadong river to derive the forecasting model of FVI at three different values of Base High Level, 2m, 2.5m and 3m. The significant predictor variables on the target variable, FVI were as follows: ground water level based on sea level with negative effect, difference between ground altitude of ground water and river level with negative effect, and difference between ground water level and river level after Bo water being filled with positive sign for quantitative variables. And for qualitative variable, effective soil depth and ground soil type were significant for FVI.

• Nuclear Engineering and Technology
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• v.16 no.3
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• pp.136-140
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• 1984

A new medal is presented in order to evaluate the risk from a nuclear facility following accidents directly combining the on-site meteorological data using the Monte Carlo Method. To estimate the radiological detriment to the surrounding population-at-large (collective dose equivalent), in this study the probability distribution of each meteorological element based upon on-site data is analyzed to generate atmospheric dispersion conditions. The random sampling is used to select the dispersion conditions at any given time of effluent releases. In this study it is considered that the meteorological conditions such as wind direction, speed and stability are mutually independent and each condition satisfies the Markov condition. As a sample study, the risk of KNU-1 following the large LOCA was calculated, The calculated collective dose equivalent in the 50 mile region population from the large LOCA with 50 percent confidence level is 2.0$\times$10$^2$ man-sievert.

• Korean Journal of Clinical Pharmacy
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• v.21 no.2
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• pp.74-80
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• 2011

Population pharmacokinetics for gentamicin were compared with 20 Korean patients (14 male and 6 female) and 25 Caucasian appendicitis patients (16 male and 9 female). Two to six blood specimens were collected from all patients at the following times : just before a regularly scheduled infusion and at 0.5 hour after the end of a 0.5 hour infusion. Nonparametric expected maximum(NPEM) algorithm for population modeling was used. The estimated parameters were the elimination rate constant(K), the slope(KS) of the relationship between K versus creatinine clearance(Ccr), the apparent volume of distribution (V), the slope(VS) of the relationship between V versus weight, gentamicin clearance(CL) and the slope(CS) of the relationship between CL versus Ccr and the V. The output includes two marginal probability density function(PDF), means, medians, modes, variance, skewness, kurtosis, and CV%. The mean K(KS) were$0.402{\pm}0.129hr^{-1}$ ($0.00486{\pm}0.00197[hr{\cdot}mL/min/1.73m^2]^{-1}$) and $0.425{\pm}0.137hr^{-1}$($0.00432{\pm}0.00168[hr{\cdot}mL/min/1.73m^2]^{-1}$) for Korean and Caucasian populations, respectively. The mean V(VS) were not different at $14.3{\pm}3.69L$($0.241{\pm}0.0511L/kg$) and $15.8{\pm}4.81L$($0.236{\pm}0.0531L/kg$) for Korean and Caucasian populations, respectively (P>0.2). The mean CL(CS) were $5.68{\pm}1.69L/hr$ ($0.0714{\pm}0.0222L/kg[hr{\cdot}mL/min/1.73m^2]$) and $6.29{\pm}1.84L/hr$ ($0.0629{\pm}0.0189L/kg[hr{\cdot}mL/min/1.73m^2]$) for Korean and Caucasian populations, respectively. There are no differences in gentamicin pharmacokinetics between Korean and Caucasian appendicitis patients.

• YAKHAK HOEJI
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• v.56 no.1
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• pp.48-54
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• 2012

Enviromental differences in gentamicin pharmacokinetics by using population pharmacokinetic methods were compared with 20 Korean patients and 24 Korean-American appendicitis patients. Two to six blood specimens were collected from all patients at the following times : just before a regularly scheduled infusion and at 0.5 hour after the end of a 0.5 hour infusion. Nonparametric expected maximum (NPEM) algorithm for population modeling was used. The estimated parameters were the elimination rate constant (K), the slope (KS) of the relationship between K versus creatinine clearance ($C_{cr}$), the apparent volume of distribution (V), the slope (VS) of the relationship between V versus weight, gentamicin clearance (CL) and the slope (CS) of the relationship between CL versus $C_{cr}$ and the V. The output includes two marginal probability density function (PDF), means, medians, modes, variance and CV%. The mean K (KS) were $0.402{\pm}0.129\;h^{-1}(0.00486{\pm}0.00197\;[h{\cdot}ml/min/1.73\;m^2]^{-1})$ and $0.411{\pm}0.135\;h^{-1}(0.00475{\pm}0.00180\;[h{\cdot}ml/min/1.73\;m^2]^{-1})$ for Korean and Korean-American populations, respectively. The mean V (VS) were not different at $14.3{\pm}3.6l(0.241{\pm}0.0511l/kg)$ and $15.1{\pm}3.84l(0.239{\pm}0.0492l/kg)$ for Korean and Korean-American populations, respectively (p>0.2). The mean CL (CS) were $5.68{\pm}1.69l/h(0.0714{\pm}0.0222l/kg[h{\cdot}ml/min/1.73\;m^2])$ and $5.70{\pm}1.77l/h(0.0701{\pm}0.0215l/kg[h{\cdot}ml/min/1.73\;m^2])$ for Korean and Korean-American populations, respectively. There were no enviromental differences in gentamicin pharmacokinetics between Korean and Korean-American appendicitis patients.