• 제목/요약/키워드: Monte carlo simulations

검색결과 689건 처리시간 0.026초

몬테카를로 방법 기반의 이동최소제곱을 이용한 밀도 데이터의 벡터장 시각화 (Visualization of Vector Fields from Density Data Using Moving Least Squares Based on Monte Carlo Method)

  • 김종현
    • 한국컴퓨터그래픽스학회논문지
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    • 제30권2호
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    • pp.1-9
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    • 2024
  • 본 논문에서는 밀도 데이터로부터 다양한 벡터장 패턴을 시각화하는 새로운 방법을 제안한다. 이를 위해 물리 기반 시뮬레이션과 기하학적 처리에서 사용되는 이동최소제곱(Moving least squares, MLS)을 이용한다. 하지만 일반적인 MLS는 벡터기반의 제약조건을 통해 고차 보간되기 때문에 밀도의 특성을 고려하지 못한다. 본 논문에서는 입력 데이터에 내포되어 있는 밀도의 특성을 효율적으로 고려하기 위해 몬테카를로 기반의 가중치를 MLS에 통합하여 다양한 형태의 백터장을 표현할 수 있도록 알고리즘을 설계한다. 결과적으로 일반적인 MLS와 발산제약 기반의 MLS 같은 기존 기법으로는 표현하기 힘든 디테일한 벡터장을 실험을 통해 보여준다.

The Precision of Lead Frame Etching Characteristics Using Monte-Carlo Simulations

  • Jeong, Heung-Cheol;Choi, Gyung-Min;Kim, Duck-Jool
    • International Journal of Precision Engineering and Manufacturing
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    • 제8권1호
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    • pp.73-78
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    • 2007
  • The objective of this work was to simulate lead frame etching characteristics to optimize the etching process, Characteristics such as the etching factor and uniformity were investigated for different actual operating conditions, including pressure, distance from the nozzle tip, pipe pitch, and feed speed. The correlation between the etching and spray characteristics was analyzed to develop the etching model. Spray characteristics obtained from an experiment using a phase Doppler anemometer system were then simulated using a Monte-Carlo technique, The etching process model was coded in the Java language, The spray and etching characteristics were correlated with each other and simulated results agreed well with the measured data for a lead frame etching process, The optimal operating parameters under various conditions were successfully determined.

THE INVESTIGATION OF BURNUP CHARACTERISTICS USING THE SERPENT MONTE CARLO CODE FOR A SODIUM COOLED FAST REACTOR

  • Korkmaz, Mehmet E.;Agar, Osman
    • Nuclear Engineering and Technology
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    • 제46권3호
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    • pp.407-412
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    • 2014
  • In this research, we investigated the burnup characteristics and the conversion of fertile $^{232}Th$ into fissile $^{233}U$ in the core of a Sodium-Cooled Fast Reactor (SFR). The SFR fuel assemblies were designed for burning $^{232}Th$ fuel (fuel pin 1) and $^{233}U$ fuel (fuel pin 2) and include mixed minor actinide compositions. Monte Carlo simulations were performed using Serpent Code1.1.19 to compare with CRAM (Chebyshev Rational Approximation Method) and TTA (Transmutation Trajectory Analysis) method in the burnup calculation mode. The total heating power generated in the system was assumed to be 2000 MWth. During the reactor operation period of 600 days, the effective multiplication factor (keff) was between 0.964 and 0.954 and peaking factor is 1.88867.

Kinetic Monte Carlo Simulations for Defects Diffusion in Ion-implanted Crystalline

  • Jihyun Seo;Hwang, Ok-Chi;Ohseob Kwon;Kim, Kidong;Taeyoung Won
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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    • pp.731-734
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    • 2003
  • An atomistic process modeling, Kinetic Monte Carlo simulation, has the advantage of being both conceptually simple and extremely powerful. Instead of diffusion equations, it is based on the definitions of the interactions between individual atoms and defects. Those interactions can be derived either directly from molecular dynamics, first principles calculations, or from experiment. In this paper, as a simple illustration of the kinetic Monte Carlo we simulate defects (self-interstitials and vacancies) diffusion after ion implantation in Si crystalline.

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성간먼지 산란 연구를 위한 효율적인 몬테카를로 알고리즘 (AN EFFICIENT MONTE-CARLO ALGORITHM FOR DUST-SCATTERING STUDY)

  • 선광일
    • 천문학논총
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    • 제25권4호
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    • pp.177-186
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    • 2010
  • We developed an efficient Monte-Carlo algorithm to solve dust-scattering radiative transfer problems for continuum radiation. The method calculates the scattered intensities for various anisotropic factors ($g_i$) all at once, while actual photon packets are tracked following a scattering phase function given by a single anisotropic factor ($g_0$). The algorithm was tested by applying the method to a dust cloud embedding a star at the cloud center and found to provide accurate results within the statistical fluctuation that is intrinsic in Monte-Carlo simulations. It was found that adopting $g_0$ = 0.4 - 0.5 in the algorithm is most efficient. The method would be efficient in estimating the anisotropic factor of the interstellar dust by comparing the observed data with radiative transfer models.

비백색 잡음을 입력으로 하는 비선형 시스템의 시뮬레이션 (Monte-Carlo Simulations of Nonlinear Systems to Non-White Excitation)

  • 김대웅;권순홍;하동대
    • 대한조선학회논문집
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    • 제31권2호
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    • pp.57-64
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    • 1994
  • 본 논문은 비선형 확률 미분 방정식의 시뮬레이션 기법을 다루었다. Monte-Carlo 해를 이 시뮬레이션 기법에 적용하였다. 이 방법은 불규칙 해상의 선박에 대한 비선형 횡요 운동을 해석하는데 적용하였다. 본 연구에서 제시한 방법의 유용성을 검증하기 위해서 시뮬레이션의 결과를 등가 선형화법과 등가 비선형화법의 결과와 비교하였다.

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Monte Carlo simulations of chromium target under proton irradiation of 17.9, 22.3 MeV

  • Kara, A.;Yilmaz, A.;Yigit, M.
    • Nuclear Engineering and Technology
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    • 제53권10호
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    • pp.3158-3163
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    • 2021
  • Chromium material is commonly used for fusion plasma facing applications because of the low neutron activation property. The Monte Carlo method is one of the useful ways to investigate the ion-target interactions. In this study, Chromium target irradiated by protons was investigated using Monte Carlo based simulation tools. In this context, the calculations of radiation damage on Chromium material irradiated with protons at 17.9 and 22.3 MeV energies were carried out using GEANT4 and SRIM codes. Besides, the cross sections for proton interaction with Chromium target were calculated by the TALYS 1.9 code using CTM + FGM, BSFGM, and GSFM level densities. As a result, GEANT4, SRIM and TALYS 1.9 codes provide a suitable tool for the predictions of radiation damage and cross cross section with proton irradiation.

Monte Carlo simulation for verification of nonparametric tests used in final status surveys of MARSSIM at decommissioning of nuclear facilities

  • Sohn, Wook;Hong, Eun-hee
    • Nuclear Engineering and Technology
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    • 제53권5호
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    • pp.1664-1675
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    • 2021
  • In order to verify the statistical performance of the nonparametric tests used in the MARSSIM approach, all plausible contamination distribution types that can be encountered in a survey area should be investigated. As the first of such investigations, this study aims to perform the verification for normal distribution of the contamination in a survey area by simulating the collection of random samples from it through the Monte Carlo simulation. The results of the simulations conducted for a total of 81 simulation cases showed that Sign test and WRS test both exhibited an excellent statistical performance: 100% for the former and 98.8% for the latter. Therefore, in final status surveys of the MARSSIM approach, a high statistical performance can be expected in applying the nonparametric hypothesis tests to survey areas whose net contamination can be assumed to be normally distributed.

신경 회로망을 이용한 보행자와의 충돌 위험 판단 방법 (Collision Risk Assessment for Pedestrians' Safety Using Neural Network)

  • 김범성;박성근;최배훈;김은태;이희진;강형진
    • 제어로봇시스템학회논문지
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    • 제17권1호
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    • pp.6-11
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    • 2011
  • This paper proposes a new collision risk assessment system for pedestrians's safety. Monte Carlo Simulation (MCS) method is a one of the most popular method that rely on repeated random sampling to compute their result, and this method is also proper to get the results when it is unfeasible or impossible to compute an exact result. Nevertheless its advantages, it spends much time to calculate the result of some situation, we apply not only MCS but also Neural Networks in this problem. By Monte carlo method, we make some sample data for input of neural networks and by using this data, neural networks can be trained for computing collision probability of whole area where can be measured by sensors. By using this trained networks, we can estimate the collision probability at each positions and velocities with high speed and low error rate. Computer simulations will be shown the validity of our proposed method.

MCS-BEq에 의한 CH4기체에서 전자에너지 분포함수 (Electron Energy Distribution function in CH4 by MCS-BEq)

  • 김상남
    • 전기학회논문지P
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    • 제62권1호
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    • pp.18-22
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    • 2013
  • This paper describes the information for quantitative simulation of weakly ionized plasma. We must grasp the meaning of the plasma state condition to utilize engineering application and to understand materials of plasma state. Using quantitative simulations of weakly ionized plasma, we can analyze gas characteristic. In this paper, the electron transport characteristic in $CH_4$ has been analysed over the E/N range 0.1~300[Td], at the 300[$_{\circ}\;K$] by the two term approximation Boltzmann equation method and Monte Carlo Simulation. Boltzmann equation method has also been used to predict swarm parameter using the same cross sections as input. The behavior of electron has been calculated to give swarm parameter for the electron energy distribution function has been analysed in $CH_4$ at E/N=10, 100 for a case of the equilibrium region in the mean energy. A set of electron collision cross section has been assembled and used in Monte Carlo simulation to predict values of swarm parameters. The result of Boltzmann equation and Monte Carlo Simulation has been compared with experimental data by Ohmori, Lucas and Carter. The swarm parameter from the swarm study are expected to sever as a critical test of current theories of low energy scattering by atoms and molecules.