• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3967-3972
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• 2011

A whole body physiologically based pharmacokinetic (PBPK) model was applied to investigate absorption, distribution, and physiologic variations on pharmacokinetics of imatinib in human body. Previously published pharmacokinetic data of the drug after intravenous (i.v.) infusion and oral administration were simulated by the PBPK model. Oral dose absorption kinetics were analyzed by adopting a compartmental absorption and transit model in gut section. Tissue/plasma partition coefficients of drug after i.v. infusion were also used for oral administration. Sensitivity analysis of the PBPK model was carried out by taking parameters that were commonly subject to variation in human. Drug concentration in adipose tissue was found to be higher than those in other tissues, suggesting that adipose tissue plays a role as a storage tissue for the drug. Variations of metabolism in liver, body weight, and blood/plasma partition coefficient were found to be important factors affecting the plasma concentration profile of drug in human body.

• Journal of the Korean Society of Safety
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• v.30 no.4
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• pp.86-91
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• 2015

The flash point is used to categorize inflammable liquids according to their relative flammability. Such a categorization is important for the safe handling, storage, and transportation of inflammable liquids. The flash point temperature of two binary liquid mixtures(n-octane+n-decane and n-octane+n-dodecane) has been measured for the entire concentration range using Seta-flash closed cup tester based on the ASTM D3278 method. The closed cup flash point temperature was estimated using the UNIFAC(Universal Functional Activity Coefficient) group contribution model. The experimentally derived flash point was also compared with the predicted flash point from the UNIFAC model. The UNIFAC model is able to estimate the flash point fairly well for n-octane+n-decane mixture and n-octane+n-dodecane mixture.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.3
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• pp.153-160
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• 1997

In order to use and conserve groundwater efficiently, in the first place the values of transmissivity and storage coefficient have to be correctly estimated. Various methods to determine hydraulic parameters of aquifer were reviewed and the characteristics of the methods were described in this paper. They were compared to obtaine parameters by various methods. An improved method to estimate the hydraulic parameters of aquifer is suggested by the comparison of the previous methods.

• Journal of Korean Society on Water Environment
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• v.24 no.2
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• pp.221-229
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• 2008

This study revised a model for hydrologically analyzing rainwater harvesting facilities considering their rainfall-runoff properties and the data available. This model has only a few parameters, which can be estimated with rather poor measurements available. The model has a non-linear module for rainfall loss, and the remaining rainfall excess (effective rainfall) is assumed to be inflow to the storage tank. This model has been applied for the rainwater harvesting facilities in Seoul National University, Korea Institute of Construction Technology, and the Daejon World Cup Stadium. As a result, the runoff coefficients estimated were about 0.9 for the building roof as a rainwater collecting surface and about 0.18 for the playground. This result is coincident with that for designing the rainwater harvesting facilities to show the accuracy of model and the simulation results.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.135-143
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• 2006

전체유역을 하나의 유역으로 처리하여 홍수량을 산정한 경우와 전체유역을 소유역으로 분할하여 홍수량을 산정한 경우의 홍수량 차이가 크게 발생하며 소유역 분할에 따른 홍수량 증가가 매우 크므로 이에 대한 개선방안이 절실히 필요하다. 이와 같이 소유역 분할에 따른 홍수량 증가가 발생하는 문제를 해결하기 위하여 홍수량 산정방법으로 가장 널리 사용되고 있는 Clark 단위도법의 두가지 매개변수 중에서 물리적인 개념이 강한 도달시간은 조정이 불가능하므로 저류상수 산정 방법을 개선하고자 한다. 저류상수 산정 공식중 Sabol 공식은 가장 합리적이며 최근 많이 채택되고 있으나 형상계수가 0.1 정도가 되면 도달시간$(T_c)$/저류상수(K)가 매우 작아지는 경향을 나타내며 이에 따라 홍수량도 매우 작게 산정되는 문제점을 야기시키므로 이를 수정하여 저류상수 산정 공식의 기본 공식으로 채택하고 보정계수를 사용하여 소유역으로 분할하여 하도추적과 합성을 통하여 홍수량을 산정할 경우 홍수량이 크게 증가하는 문제를 해결하도록 저류상수 산정 공식을 제시하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.552-555
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• 2004

The reliability issue of the probe tip/recording media interface is one of the most crucial concerns in the Atomic Force Microscope (AFM)-based recording technology. In this work, the tribological characteristics of the probe/media interface were investigated by performing wear tests using an AFM. The ranges of applied normal load and sliding velocity for the wear test were 10 to 50nN and 2 to 20$\mu$m/s respectively. The damage of the probe tip was quantitatively as well as qualitatively characterized by Field Emission Scanning Probe Microscope (FESEM) analysis and calculated based on Archard s wear equation. It was shown that the wear coefficient of the probe tip was in the order of 10$^{-4}$ ~ 10$^{-3}$ , and significant contamination at the end of the probe tip was observed. Thus in order to implement the AFM-based recording technology, tribological optimization of the probe/media interface must be achieved.

• Journal of Electrical Engineering and Technology
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• v.11 no.2
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• pp.499-507
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• 2016

Medical imaging techniques such as Magnetic Resonance Imaging (MRI), Computed Tomography (CT) and Ultrasound (US) produce a large amount of digital medical images. Hence, compression of digital images becomes essential and is very much desired in medical applications to solve both storage and transmission problems. But at the same time, an efficient image compression scheme that reduces the size of medical images without sacrificing diagnostic information is required. This paper proposes a novel threshold-based medical image compression algorithm to reduce the size of the medical image without degradation in the diagnostic information. This algorithm discusses a novel type of thresholding to maximize Compression Ratio (CR) without sacrificing diagnostic information. The compression algorithm is designed to get image with high optimum compression efficiency and also with high fidelity, especially for Peak Signal to Noise Ratio (PSNR) greater than or equal to 36 dB. This value of PSNR is chosen because it has been suggested by previous researchers that medical images, if have PSNR from 30 dB to 50 dB, will retain diagnostic information. The compression algorithm utilizes one-level wavelet decomposition with threshold-based coefficient selection.

• The Journal of Engineering Geology
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• v.4 no.3
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• pp.311-319
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• 1994

This paper presents a sensitivity analysis to obtain best fit of hydraulic parameters of leaky fractal aquifer. The sensitivity analysis uses the least squares method. The hydraulic parameters (generalized transmissivity and generalized storage coefficient) can be easily determined by the sensitivity analysis for various flow dimensions and different values of the leakage factor. Furthermore, the sensitivity analysis was applied to variable-rate pump tast at several abstraction wells, A computer program was developed to evaluate the hydraulic parameters by the sensitivity analysis.

• Journal of Biosystems Engineering
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• v.23 no.4
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• pp.335-342
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• 1998

The objectives of this study were to evaluate respiration characteristics and develop empirical respiratory rate equations for short gain rough rice. The carbon dioxide concentrations generated from mush rice at four level temperatures(10, 20, 30, 4$0^{\circ}C$) and 4 level moisture contents(17.2, 21.5, 25.9, 31.6％, d.b.) were measured by gas chromatography. The respiratory rates' increased exponentially with gain temperature and also with moisture content The relationship between respiratory rate and gain temperature fitted the Arrehenius' and Core's equations very well. Two empirical respiratory rate equations were presented as a function of gain temperature and moisture content. The values of determination coefficient for the developed respiratory rate equations were 0.999, and the result of t-test showed that there were no significant differences between predicted and measured respiratory rates on significance level of 1%. Therefore, it appeared that respiratory rates predicted by the respiratory rate equations agreed well with measured values. An equation for predicting dry matter losses of rough rice during storage was presented by modifying the respiratory rate equations based on chemical reaction of decomposition of carbohydrate.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.1
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• pp.56-63
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• 2013

This study was aimed at developing and evaluating a diffusive sampling method using a barium hydroxide solution as an absorbent for measuring carbon dioxide ($CO_2$) in ambient air. The collected $CO_2$ concentration was calculated by the change of conductivity resulted in the reaction of $CO_3{^{2-}}$ and $Ba^{2+}$ in aqueous solution. The sampling rate for the diffusive sampler was determined 0.218 mL/min, as obtained from the slope of the linear correlation between the $CO_2$ mass collected by the diffusive sampler and the time-weighted $CO_2$ concentration with the active sampling method. The unexposed blank sampler sealed in aluminium foil-polyethylene laminated packets has remained stable during at least one-month storage period. A good correlation was observed between the diffusive sampler and active sampler with a coefficient of determination of 0.956. This diffusive sampler would be suitable for the indoor $CO_2$ concentration monitoring.