• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.164-167
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• 2001

The electron transport coefficients, the electron drift velocity W, the longitudinal diffusion coefficient $ND_L$ and $D_L/{\mu}$, in pure $CO_2$ were calculated over the wide E/N range from 0.01 to 500 Td at 1 Torr by two-term approximation of the Boltzmann equation for determination of electron collision cross sections set and for quantitative characteristic analysis of $CO_2$ molecular gas. And for propriety of two-term approximation of Boltzmann equation analysis, the calculated results compared with the electron transport coefficients measured by Nakamura.

• 한국환경과학회지
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• 제13권10호
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• pp.903-909
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• 2004

A new method based on solid phase microextraction(SPME), coupled with GC/FID, has been developed for the determination of PCE and TCE in water samples. The experimental parameters affecting the SPME process (i.e, kinds of fibers, extraction time, desorption time, extraction temperature, volume ratio of sample to headspace, salt addition, and magnetic stirring) were optimized. The coefficients of determination ($R^2$) for PCE and TCE were 0.9951 and 0.9831, respectively when analytes concentration ranges from 10 to 300$\mu$g/L. The relative standard deviations were 3.4 and $2.1\%$ for concentration of 10$\mu$g/L(n=5), respectively. The detection limits of PCE and TCE were 0.5 and l.3$\mu$g/L, respectively.

• 산업경영시스템학회지
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• 제18권36호
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• pp.365-370
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• 1995

In recent years, there have been attempts to explain firms' capital structure based upon the agency theory which considers agency problems arising due to ownership structure. Agency theory starts from the coctractual relationship (explicit or implicit) between principals and agents. Since uncertainty exists in real world and information is distributed asymmetrically, there are conflicts between principals and agents. The objectives of this study are to analyze, based upon agency theory, factors which are expected to affect firms' capital structure and to test empirically the relevance of agency cost hypothesis about the determination of capital structure, For these purposes, this paper carried out multiple regression in order to examine whether the factors of agency costs affect significantly the determination of capital structure. The results of empirical analysis are summarrized as follows; First, insider-equity ration has been negatively correlated with capital structure. Second, growth opportunity variabless has been insignificant coefficients with capital structure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.281-283
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• 1998

The 4-poles LHSM with transverse bar track was designed on the base of the performance equations and the equivalent circuit model. However, the magnetic shape factors, such as Carter's and Green's coefficients, $B_{min}/B_{max}$ and leakage factors, were important in the design and analysis of LHSM. Consequently, these coefficients were computed from the analytical expressions and examined from FEM analysis in detail.

• Asian-Australasian Journal of Animal Sciences
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• 제18권4호
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• pp.580-583
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• 2005

We have evaluated the application of spectroscopy using an insertion-type fiber-optic probe and a sensor at wavelengths from 400 to 1,100 nm to the measurement of milk fat content on dairy farms. The internal reflectance ratios of 183 milk samples were determined with a fiber-optic spectrophotometer at 5$^{\circ}C$, 20$^{\circ}C$ and 40$^{\circ}C$. Partial least squares (PLS) regression was used to develop calibration models for the milk fat. The best accuracy of determination was found for an equation that was obtained using smoothed internal reflectance data and three PLS factors at 20$^{\circ}C$. The correlation coefficients between predicted and reference milk fat at 5$^{\circ}C$, 20$^{\circ}C$ and 40$^{\circ}C$ were r=0.753, r=0.796 and r=0.783, respectively. The predictive explained variances ($Q^2$) of the final model, moreover, were more than 0.550 at all temperatures, and the regression coefficients of determination ($R^2$) were more than 0.6 (60%). Our results indicate that milk has different internal reflectance measured in the range of visible and near infrared wavelengths (400 to 1,100 nm), depending on its fat content.

• 한국농공학회논문집
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• 제52권6호
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• pp.39-48
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• 2010

Sediment yields from Imha watershed were simulated during 1993-2008 using Hydrologic Simulation Program-Fortran (HSPF). Using observed daily stream flow for 2004-2008 and hourly suspended solid concentration for three events during 2006, HSPF was calibrated and validated at the sites of Imha and Youngyang for stream flow and Dongchun and Jangpachun for sediment yield. The calibration and validation results represented high model efficiency for simulating daily stream flow and hourly suspended solid. The determination coefficients of calibration and validation were 0.90 and 0.81 for daily stream flow, and 0.91 and 0.86 for monthly stream flow, respectively. Based on model tolerances for calibration and validation of stream flow, HSPF performance for simulating stream flow represented 'very good'. The determination coefficients of calibration and validation were 0.94-0.96 and 0.95 for hourly sediment yields, respectively. The average yearly sediment yield during 1993-2008 was 122,290 ton/year and most of sediment yield (77 % of total yield) were generated from June to August. The calibrated HSPF simulated well the movement of water and eroded soil within Imha watershed.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.147-150
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• 2004

수자원을 평가하기 위해서는 먼저 한 지점에서 측정된 강수량을 보간해야 할 필요가 있다. 이를 위하여 강수현상에 영향을 주는 지형변수를 TOVA(Topographic Variables Extraction Program)를 이용하여 고도(ELEV), 경사(SLOPE), 바다까지의 거리(SEA), 방해물(OBST), 방벽(BAR), 굴곡도(SHIELD)로 구분하고 2000.1.1부터 2002.12.31까지의 강수량 자료를 사상별로 추출하여 이들을 서로 비교 분석하였다. 결정계수로 보면 각기 강수사상마다 지형의 영향이 다르게 나타나며 ELEV와 남서방향의 SLOPE, OBST 그리고 전 방향의 SHIELD가 강수량과 관계가 깊은 것으로 나타났다. 다중회귀분석 모형은 강수량의 공간적 변동량의 96%를 설명한다.

• 산업융합연구
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• 제20권11호
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• pp.65-74
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• 2022

본 연구는 COVID-19 시기에 간호학과에 입학한 신입생의 자기결정성동기, 대인관계조화와 학업적 자기효능감의 정도를 확인하고 학업적 자기효능감에 영향을 미치는 요인을 파악하고자 시도되었다. 자료 수집은 2021년도 11월 01일부터 11월 30일까지이며, 연구대상자는 C 시에 소재한 대학교의 간호학과에 재학중인 신입생 220명이다. 자료 분석은 SPSS 25.0을 이용하여 t-test, ANOVA 및 Scheffé 사후검정, Pearson correlation coefficients 산출 및 다중회귀분석을 실시하였다. 연구 결과는 1학기에 대면수업 경험, 전공선택이유, 자기결정성동기와 대인관계조화가 학업적 자기효능감 총변동의 47.9%를 설명하고 있었다, 그리고 11학기 1개 교과목 이상 대면 수업, 자기결정성동기와 대인관계조화가 학업적 자기효능감에 유의한 영향을 미치는 것으로 나타났다. 간호학과 신입생의 학업적 자기효능감을 향상시키기 위하여 자기결정성동기를 지지하고 대인관계를 조화롭게 형성하기 위한 프로그램이 개발되고 적용되어야 할 것이다.

• Advances in Computational Design
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• 제5권3호
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• pp.305-321
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• 2020

In this paper is presented the solution method for three-dimensional problem of transversely isotropic body's elastoplastic deformation by the finite element method (FEM). The process of problem solution consists of: determining the effective parameters of a transversely isotropic medium; construction of the finite element mesh of the body configuration, including the determination of the local minimum value of the tape width of non-zero coefficients of equation systems by using of front method; constructing of the stiffness matrix coefficients and load vector node components of the equation for an individual finite element's state according to the theory of small elastoplastic deformations for a transversely isotropic medium; the formation of a resolving symmetric-tape system of equations by summing of all state equations coefficients summing of all finite elements; solution of the system of symmetric-tape equations systems by means of the square root method; calculation of the body's elastoplastic stress-strain state by performing the iterative process of the initial stress method. For each problem solution stage, effective computational algorithms have been developed that reduce computational operations number by modifying existing solution methods and taking into account the matrix coefficients structure. As an example it is given, the problem solution of fibrous composite straining in the form of a rectangle with a system of circular holes.

• 한국정밀공학회지
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• 제32권2호
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• pp.185-190
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• 2015

This paper presents a new method to determine sensitivity coefficients of temperature and humidity of torque transducers by using a natural and seasonal variation of ambient conditions at the laboratory. We had measured the sensitivities of the torque transducers over almost one year using the KRISS 2 kN m torque standard machine. The sensitivity data acquired at various ambient conditions were processed using our measurement model to extract the sensitivity coefficients of temperature and humidity simultaneously with high precision. A comparison with a previous method using an environmental control chamber was carried out to test the feasibility of using our new method. Two results agreed within the uncertainty. We revealed that the torque measuring errors could be 8 times higher than the measurement and calibration capability of KRISS torque standard machine if the sensitivity changes due to the temperature and humidity are not properly corrected during a calibration.