• Title/Summary/Keyword: Statistical-Mechanical Model

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Parametric Effects of Elastic Property Extraction System of Polycrystalline Thin-Films for Micro-Electro-Mechanical System Devices (MEMS 부품을 위한 다결정 박막의 탄성 물성치 추출 시스템의 매개변수의 영향)

  • 정향남;최재환;정희택;이준기
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.50-54
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    • 2004
  • A numerical system to extract effective elastic properties of polycrystalline thin-films for MEMS devices is already developed. In this system, the statistical model based on lattice system is used for modeling the microstructure evolution simulation and the key kinetics parameters of given micrograph, grain distributions and deposition process can be extracted by inverse method proposed in the system. In this work, the effects of kinetics parameters on the extraction of effective elastic properties of polycrystalline thin-films are studied by using statistical method. The effects of the fraction of the potential site( $f_{P}$ ) and the nucleation probability( $P_{N}$ ) among the parameters for deposition process of microstructure on the extraction of effective elastic properties of polycrystalline thin-films are studied.d.d.

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Elastic Property Extraction System of Polycrystalline Thin-Films for Micro-Electro-Mechanical System Device and Application to Polycrystalline Materials (MEMS 부품을 위한 다결정 박막의 탄성 물성치 추출 시스템과 다결정 재료의 적용)

  • Jung H. N.;Choi J. H.;Chung H. T.;Lee J. K.
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2004.10a
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    • pp.19-22
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    • 2004
  • A numerical system to extract effective elastic properties of polycrystalline thin-films for MEMS devices is already developed. In this system, the statistical model based on lattice system is used for modeling the microstructure evolution simulation and the key kinetics parameters of given micrograph, grain distributions and deposition process can be extracted by inverse method proposed in the system. In this work, the effective elastic properties of polysilicon, $BaTiO_3\;and\;ZrTiO_4$ are extracted using this system and by employing the fraction of the potential site($f_P$) as a kinetics parameter for the microstructure evolution, the statistical tendency of these materials is studied.

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The effective model of the human Acetyl-CoA Carboxylase inhibition by aromatic-structure inhibitors

  • Minh, Nguyen Truong Cong;Thanh, Bui Tho;Truong, Le Xuan;Suong, Nguyen Thi Bang;Thao, Le Thi Xuan
    • Journal of IKEEE
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    • v.21 no.3
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    • pp.309-319
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    • 2017
  • The research investigates the inhibition of fatty acid biosynthesis of the human Acetyl-CoA Carboxylase enzyme by the aromatic-structure inhibitors (also known as ligands) containing variables of substituents, contributing an important role in the treatment of fatty-acid metabolic syndrome expressed by the group of cardiovascular risk factors increasing the incidence of coronary heart disease and type-2 diabetes. The effective interoperability between ligand and enzyme is characterized by a 50% concentration of enzyme inhibitor ($IC_{50}$) which was determined by experiment, and the factor of geometry structure of the ligands which are modeled by quantum mechanical methods using HyperChem 8.0.10 and Gaussian 09W softwares, combining with the calculation of quantum chemical and chemico-physical structural parameters using HyperChem 8.0.10 and Padel Descriptor 2.21 softwares. The result data are processed with the combination of classical statistical methods and modern bioinformatics methods using the statistical softwares of Department of Pharmaceutical Technology - Jadavpur University - India and R v3.3.1 software in order to accomplish a model of the quantitative structure - activity relationship between aromatic-structure ligands inhibiting fatty acid biosynthesis of the human Acetyl-CoA Carboxylase.

Analysis of Probability Distribution of Muzzle Velocity for Chrome Plated Barrel (크롬도금 포열의 포구속도 확률분포 특성 분석)

  • Kim, Jaekab;Kim, Jaehoon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.24 no.4
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    • pp.401-407
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    • 2021
  • To confirm the change of muzzle velocity and the most suitable probability distribution model of the 155 mm K9 howitzer barrel with chrome plating and changed rifling. Using a statistical program, the muzzle velocity were plotted on a normal distribution, a 2-parameter and 3-parameter Weibull distribution on a probability paper. Also, statistical parameters were estimated and muzzle velocity fitness test and probability of K676 charge were plotted. In both the chrome-plated with standard rifling and changed rifling for K9 barrel, the 2-parameter and 3-parameter Weibull distribution were skewed to the left compared to the normal distribution. It was confirmed that the muzzle velocity of the K9 barrel with chromium-plated is suitable for the normal distribution and 3-parameter Weibull distribution model.

Study on the Flame Structures of Counter Flow Flames by Using Different Gas Radiation Models (가스 복사 모델에 따른 대향류화염에서의 화염 구조 연구)

  • Park, Won-Hee;Kim, Dong-Hyun;Kim, Tae-Kuk
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.1493-1498
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    • 2004
  • WSGGM with gray gas regrouping is successfully applied to study the flame structure of counter flow flames including effect of radiative transfer. The statistical narrow band model is used to obtain the benchmark solutions. Results obtained by using the optically thin model are shown to overestimate the emission and to predict the flame structures inadequately especially for optically thick and low stretch rate flames. Computed results by using the WSGGM with 10 gray gases and SNB model show reasonable agreements with each other, and the required calculation time for the WSGGM is acceptable for engineering applications.

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Partitioning and Diffusion Properties of Hydrogen Gases In Porous Membranes Using the Nonoverlapping Sphere Model (비겹침 구형 모델을 이용한 세공 박막 내 수소 기체의 분산 및 확산 특성)

  • Suh, Soong-Hyuck;Ha, Ki-Ryong
    • Journal of Hydrogen and New Energy
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    • v.9 no.3
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    • pp.119-125
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    • 1998
  • The modified statistical-mechanical theory for dense fluid mixtures of rigid spheres has been applied to rigid sphere fluids in the nonoverlapping pore model. The resulting expressions for the partition coefficient and diffusivity illustrate the influence of steric hindrance on the thermodynamic and transport properties in such systems. The open membrane model without the size-exclusion and shielding effects shows considerable overestimation of the diffusion flux when the effective mean pore radii of the order of $20{\AA}$ or less are involved. Theoretical predictions investigated here were also compared with experimental data for hydrogen gases in inorganic porous membranes and it was observed a qualitative agreement in the low pressure limit.

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A Statistical Analysis of Joint Moments Acting on Men Performing a Seated Dynamic Task (앉은 자세에서 동적 작업을 수행할 때 작용하는 관절 모멘트의 통계학적 해석)

  • Jung, Ho-Il;Son, Kwon
    • Progress in Medical Physics
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    • v.2 no.2
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    • pp.161-173
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    • 1991
  • A statistical approach was carried out to analyze joint moments acting on the six subjects performing a right-handed seated task. The dynamic task analyzed consisted of moving a hand-held weight of lkg mass back and forth in front of a subject's chest at the shoulder level in an upright seated position. We used experimental data obtained in the Biomechanics Laboratory of the University of Michigan. Based on the acquired data from three trials by each subject, moments were calculated using a 3-dimensional biomechanical model at such articulations as wrist, elbow, shoulder, the third lumbar spine, hip, knee, and ankle joints. The linear correlation and the two way analysis of variance were applied to the calculated joint moments in order to investigate inter-subject and inter-trial varations. The results obtained showed that the largest magnitude and deviation of moment was found at the third lumbar spine, that any linear relationship could not be found between moment and its equivalents attempted in this study, and that the maximum value and deviation of moment acting on each joint were statistically the same for all three trials but those were statistically not the same for all six subjects.

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Statistical Analysis on Residuals from No-Fault Reference Models of a Residential Heat Pump System in Normal Cooling Operation (가정용 열펌프 시스템의 정상냉방 운전조건에서 기준모델에 의한 잔차의 통계적 분석)

  • Kim, Min-Sung;Yoon, Seok-Ho;Baik, Young-Jin
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.12
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    • pp.1351-1358
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    • 2011
  • To approximate the threshold of the fault detection and diagnosis (FDD) system, validation of the measurements is mandatory. Naturally, the system shows uncertainties due to measuring sensors - mostly thermocouples or RTDs - and due to repeatability. The uncertainty of a thermocouple comes from natural variation or a drift of the thermocouple measurement. Considering the natural variation behaves like zero-mean white noise, its natural variation can be characterized closely by the steady-state standard deviation. However, residuals between measurements and no-fault references in FDD systems show a statistical distribution with various uncertainties. In this paper, steady-state variations of measurement residuals were investigated by utilizing built-in temperature sensors in a heat pump for the model development and the final application.

Fatigue life prediction based on Bayesian approach to incorporate field data into probability model

  • An, Dawn;Choi, Joo-Ho;Kim, Nam H.;Pattabhiraman, Sriram
    • Structural Engineering and Mechanics
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    • v.37 no.4
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    • pp.427-442
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    • 2011
  • In fatigue life design of mechanical components, uncertainties arising from materials and manufacturing processes should be taken into account for ensuring reliability. A common practice is to apply a safety factor in conjunction with a physics model for evaluating the lifecycle, which most likely relies on the designer's experience. Due to conservative design, predictions are often in disagreement with field observations, which makes it difficult to schedule maintenance. In this paper, the Bayesian technique, which incorporates the field failure data into prior knowledge, is used to obtain a more dependable prediction of fatigue life. The effects of prior knowledge, noise in data, and bias in measurements on the distribution of fatigue life are discussed in detail. By assuming a distribution type of fatigue life, its parameters are identified first, followed by estimating the distribution of fatigue life, which represents the degree of belief of the fatigue life conditional to the observed data. As more data are provided, the values will be updated to reduce the credible interval. The results can be used in various needs such as a risk analysis, reliability based design optimization, maintenance scheduling, or validation of reliability analysis codes. In order to obtain the posterior distribution, the Markov Chain Monte Carlo technique is employed, which is a modern statistical computational method which effectively draws the samples of the given distribution. Field data of turbine components are exploited to illustrate our approach, which counts as a regular inspection of the number of failed blades in a turbine disk.

Shape Optimum Design of Ship's Bellows Using Statistical Method (통계적 방법을 이용한 선박용 벨로우즈의 형상 최적 설계)

  • Kim, Hyun-Su;Kim, Hyo-Gyeum;Lee, Jae-Sub;Kim, Hyoung-Jun
    • Journal of Ocean Engineering and Technology
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    • v.21 no.5
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    • pp.55-60
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    • 2007
  • Bellows are mechanical components which prevent the damage of system by absorption of the vibration and the displacement of axle and radial direction. Thermal piping system is expanded by the fluid of the high temperature from the heat engine inside. At this time, bellows prevent the damage of the piping due to the thermal expansion. Recently, design of bellows is required to fit some other operational environments which are not suggested in the E.J.M.A code book. And it is difficult to produce and to maintain bellows of high temperature and high pressure bemuse of its complicated shape and this causes the manufacturing cost to rise. The objective of this study is to determine optimum shape of bellows which can endure in the high temperature and high pressure. The maximum stress has an effect on the fatigue life of bellows, therefore it needs to be minimized. This study attempts to find a shape which minimizes the stress occurring in the bellows by the design of experiment. The model used in this study is not presented in the E.J.M.A code book, therefore, from the result of design of experiment we find the factors which give effects on the characteristic value and we presents the recession model using the RSM, which can predict the characteristic values depending on the change of factor values.