• Title/Summary/Keyword: intrinsic mean

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Relationship between Film Density and Electrical Properties on D.C. Magnetron Reactive Sputtered Sn-doped ${In_2}{O_3}$Films (D.C. 마그네트론 반응성 스퍼터링법에 의한 Sn-doped ${In_2}{O_3}$ 박막의 밀도와 전기적 특성과의 관계)

  • 이정일;최시경
    • Journal of the Korean Ceramic Society
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    • v.37 no.7
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    • pp.686-692
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    • 2000
  • Tin-doped In2O3 (ITO) films were fabricated using a d.c. magnetron reactive sputteirng of a In-10 wt% Sn alloy target in an Ar and O2 gas mixture. To understand the behavior of the carrier mobility in ITO films with O2 partial pressure, the resistivity, carrier concentration and mobility, film density, and intrinsic stress in the films were measured with O2 partial pressure. It was found experimentally that the carrier mobility increased rapidly as the film density increased. In the ITO film with the density close to theoretical one, the mean free path was the same as the columnar diameter. This indicated that the mobility in ITO films was strongly influenced by the crystall size. However, in the case where the film density was smaller than a theoretical density, the mean free paths were also smaller the columnar diameter. It was analyzed that the electron scattering at pores and holes within the crystalline was the major obstacle for electron conduction in ITO films. The measurement of intrinsic stress in ITO films also made it clear that the density of ITO films was controlled by the bombardment of oxygen neutrals on the growing film.

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Shape Deformation of Triangular Net (삼각망의 형상 변형)

  • Yoo, Dong-Jin
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.11
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    • pp.134-143
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    • 2007
  • A new approach based on mean value coordinate combined with Laplacian coordinate is proposed for shape deformation of a large polygon model composed of triangular net. In the method, the spherical mean value coordinates for closed control meshes is introduced to describe a vertex in the triangle meshes to be deformed. Furthermore, the well known quardratic least square method for the Laplacian coordinates is employed in order to deform the control meshes. Because the mean value coordinates are continuous and smooth on the interior of control meshes, deforming operation of control meshes change the shape of polygon model while preserving the intrinsic surface detail. The effectiveness and validity of this novel approach was demonstrated by using it to deform large and complex polygon models with arbitrary topologies.

University Student Characteristics of Type of Job Values and Key Competency

  • Bok, Mi-Jung
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.5
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    • pp.47-53
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    • 2018
  • This study is aimed to determine types of job values which is searched by 242 university student in Gwangju, to study characteristics of each type, and to analyze key competency of each type. The data were analyed with PASW 18.0 using frequency analysis, k-mean cluster analysis, crosstabs and one-way ANOVA. According to findings, first of all, university student types of job values are divided into 4 groups; a type of intrinsic job values(27.7%), a type of active job value(32.2%), a type of external job value(12.4%), a type of passive job value(27.7%). Secondly, the type of job values showed statistically significant difference only in the monthly allowance of socio-economic variables. Thirdly, the type of job values showed statistically significant difference 'communication', 'mathematics', 'problem solving', 'self development', 'resource management', 'interpersonal skills', 'technical ability', 'understanding organizations' and 'work ethics'.

Multi-Characteristic Robust Design Methodology Based on Designer's Preference (설계자 선호도를 고려한 다특성 강건설계법)

  • 김경모
    • Journal of Korean Society for Quality Management
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    • v.29 no.1
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    • pp.47-61
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    • 2001
  • The ever increasing demands for enhanced competitiveness of engineered products require a "designing-in-quality" strategy that can effectively and efficiently incorporate multiple design objectives into design. Robust design can be viewed as a multi-characteristic design problem requiring tradeoffs between mean and variance characteristics. Firstly this paper analyzes the intrinsic preference of the traditional SN ratio on mean and variance, and secondly presents a new design metric for a robust design using concepts from utility theory to accurately capture designer′s intent and preference on mean and variance. The steps to apply the proposed design metric as the robust design criterion in an orthogonal array based engineering experimentation is presented with the aid of a demonstrative case study. The performance of the proposed design metric is tested, and the results are discussed.

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Fall Risk Assessment of the Elderly living in Nursing Home (노인요양시설 거주 노인의 낙상 위험요인 조사 연구)

  • Yang, Sun-Hee;Park, Young-Hae;Cho, Hae-Sook;Baek, Hee-Chong
    • Journal of Home Health Care Nursing
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    • v.12 no.2
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    • pp.1-15
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    • 2005
  • Purpose: This study was conducted to assess the fall risk factors. Method: The subjects were 87 persons who were older than 65 years living at 28 nursing home in Seoul and Gyunggi province. Subjects were interviewed using RAFS II for intrinsic factor and the environmental factor were assessed using a structured questionnaire from Oct. to Dec. in 2004. The data were analyzed by SPSS(ver. 12.0) programs, using descriptive statistics, $x^2$-test, and t-test. Result: The 37.9% of the subjects experienced the fall, and its average number is $1.94\pm1.75$. The Women's experience of the fall was higher than that of the men, but it was no significant difference with gender. There was no significant difference with the age and duration of living. The mean of the intrinsic risk factor was 13.38 in total score 39 points marks on the RAFS II scales. The intrinsic risk factor score of the fallen group 15.71 was significantly higher than the non-fallen group 12.10. The variables of recent fall experience(t=4.72, p=0.000) and urinary dysfunction(t=2.64, p=0.010) was significantly higher than the non-fallen group. The highest variable of the intrinsic factor was the age and the variables of drug intake, balance, chronic disease, recent fall experience, urinary dysfunction were followed in order. The mean of the environmental risk factor was 0.24 points. No significant differences were shown in environmental risk factor between the fallen and the non-fallen groups. To the fallen group, the place of entrance was the highest risky environmental factor. To see in area dimension, the floor surfaces was the highest risky environmental factor and equipment and illumination factor was the following risky elements in order. In the total score of environmental risk factors based on the ares, the fallen group was 0.26 and the non-fallen group was 0.24, but there were no significant differences between the groups. Conclusion: This results suggested that visual protection strategy, set up the safety device in the place of entrance and inner stairway, bathroom and nonskid mat in the nursing home would be contribute to the prevention of the fall for the elderly.

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Accuracy of Multiple Outlier Tests in Nonlinear Regression

  • Kahng, Myung-Wook
    • Communications for Statistical Applications and Methods
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    • v.18 no.1
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    • pp.131-136
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    • 2011
  • The original Bates-Watts framework applies only to the complete parameter vector. Thus, guidelines developed in that framework can be misleading when the adequacy of the linear approximation is very different for different subsets. The subset curvature measures appear to be reliable indicators of the adequacy of linear approximation for an arbitrary subset of parameters in nonlinear models. Given the specific mean shift outlier model, the standard approaches to obtaining test statistics for outliers are discussed. The accuracy of outlier tests is investigated using subset curvatures.

Prediction of Intrinsic Pore Properties of Ultrafiltration Membrane by Solute Rejection Curves (용질배제 곡선에 의한 한외여과 막의 세공특성 예측)

  • 염경호
    • Proceedings of the Membrane Society of Korea Conference
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    • 1991.10a
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    • pp.4-8
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    • 1991
  • The characterization of pore properties (mean pore size and pore size distribution) of the active layer in a UF membrane is important not only in order to obtain information about the factors affecting pore formation during membrane manufacturing but also to understand deeply the mechanism of solute and solvent transport through pores. Many methods of characterizing quantitatively the pore properties of UF membranes have been suggested in the literature: solvent and gas flow measurement, bubble point determination, electron microscopy, gas adsorption/desorption measurement, rejection measurement etc. But most of these methods involve time-consuming procedures and involve some wellknown problems and uncertainties.

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The Configuration and Polyelectrolyte Behavior of Carboxymethyl Chitin in Low Concentration Solution (저농도 용액에서의 Carboxymethyl Chitin의 사슬배좌와 전해질 거동)

  • PARK Seong-Min;LEE Keun-Tae;KIM Sang-Moo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.4
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    • pp.451-456
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    • 1995
  • To elucidate the intrinsic rheological properties of carboxymethyl chitin (CM-chitin) from the shell of red snow cyab (Chinonecetes japonicus), the configuration and polyelectrolyte behavior of CM-chitin in low concentration solution were investigated. Unperturbed dimensions were ranged from $127{\AA}\;to\;113{\AA}$ as root mean square end-to-end distance$(r_0)$, $52{\AA}$ to $46{\AA}$ as radius of gyration$(S_0)$. The intramolecular expansion tarter(a) was not varied with molecular weight and was 2.1. And effective bond length $(b_0)$ was $14.5{\AA}$. In perturbed condition, Flory constant was $2.35\times10^{21}$. When ionic strength were 0.02 and 1.0, intrinsic viscosity were 1.95dl/g and 1,06 dl/g, respectively. These results suggested that CM-chitin is a polyelectrolyte in aqueous media. At infinite ionic strength, intrinsic viscosity was 0.91dl/g. The intrinsic stiffness of CM-chitin backbone was estimated by evaluating the stiffness parameter (B) as 0.11 and agreed well with the results of k-carrageenan.

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A Study on the Effective Hydraulic Conductivity of an Anisotropic Porous Medium

  • Seong, Kwanjae
    • Journal of Mechanical Science and Technology
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    • v.16 no.7
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    • pp.959-965
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    • 2002
  • Effective hydraulic conductivity of a statistically anisotropic heterogeneous medium is obtained for steady two-dimensional flows employing stochastic analysis. Flow equations are solved up to second order and the effective conductivity is obtained in a semi-analytic form depending only on the spatial correlation function and the anisotropy ratio of the hydraulic conductivity field, hence becoming a true intrinsic property independent of the flow field. Results are obtained using a statistically anisotropic Gaussian correlation function where the anisotropy is defined as the ratio of integral scales normal and parallel to the mean flow direction. Second order results indicate that the effective conductivity of an anisotropic medium is greater than that of an isotropic one when the anisotropy ratio is less than one and vice versa. It is also found that the effective conductivity has upper and lower bounds of the arithmetic and the harmonic mean conductivities.

Thermal transport in thorium dioxide

  • Park, Jungkyu;Farfan, Eduardo B.;Enriquez, Christian
    • Nuclear Engineering and Technology
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    • v.50 no.5
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    • pp.731-737
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    • 2018
  • In this research paper, the thermal transport in thorium dioxide is investigated by using nonequilibrium molecular dynamics. The thermal conductivity of bulk thorium dioxide was measured to be 20.8 W/m-K, confirming reported values, and the phonon mean free path was estimated to be between 7 and 8.5 nm at 300 K. It was observed that the thermal conductivity of thorium dioxide shows a strong dependency on temperature; the highest thermal conductivity was estimated to be 77.3 W/m-K at 100 K, and the lowest thermal conductivity was estimated to be 4.3 W/m-K at 1200 K. In addition, by simulating thorium dioxide structures with different lengths at different temperatures, it was identified that short wavelength phonons dominate thermal transport in thorium dioxide at high temperatures, resulting in decreased intrinsic phonon mean free paths and minimal effect of boundary scattering while long wavelength phonons dominate the thermal transport in thorium dioxide at low temperatures.