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蒙特卡罗方法在放疗计划中的应用 被引量:19
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作者 陈朝斌 黄群英 +1 位作者 吴宜灿 林辉 《核技术》 EI CAS CSCD 北大核心 2006年第1期22-28,共7页
本文就蒙特卡罗方法在放射外科治疗计划中的应用做了初步的研究和分析。首先利用Beam程序模拟了Varian公司Clinac2100C6MVX射线加速器治疗头,得到源皮距为100cm、射野大小为5cm×5cm的开放野治疗平面上的粒子相–空间信息,并与文献... 本文就蒙特卡罗方法在放射外科治疗计划中的应用做了初步的研究和分析。首先利用Beam程序模拟了Varian公司Clinac2100C6MVX射线加速器治疗头,得到源皮距为100cm、射野大小为5cm×5cm的开放野治疗平面上的粒子相–空间信息,并与文献进行了比较。然后把粒子相–空间信息作为输入,利用Dosxyz程序计算了体模中吸收剂量的空间分布,并与一基于解析剂量计算方法的商用治疗计划软件的结果进行了比较,两种结果基本一致。另外,本文还重点介绍了由患者的医学CT图像建立蒙特卡罗输运几何的方法和过程。 展开更多
关键词 放射治疗计划 蒙特卡罗方法 CT图像 剂量计算 精确放疗计划系统(ARTS)
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普贤堆退役放射性评价方法及主蒸汽管道室的中子能谱计算
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作者 沈瑾 杨洪润 《核动力工程》 EI CAS CSCD 北大核心 2004年第6期555-558,共4页
介绍了日本普贤堆(Fugen)的概况和主要设计参数,以及该堆今后的技术发展趋势。根据该堆的退役现状,介绍日本的退役战略方针以及普贤堆采用的退役方法和今后的退役步骤,并采用MCNP程序对普贤核电厂主蒸汽管道内蒸汽17N(β,n)反应产生的... 介绍了日本普贤堆(Fugen)的概况和主要设计参数,以及该堆今后的技术发展趋势。根据该堆的退役现状,介绍日本的退役战略方针以及普贤堆采用的退役方法和今后的退役步骤,并采用MCNP程序对普贤核电厂主蒸汽管道内蒸汽17N(β,n)反应产生的相对中子通量和中子能谱进行计算,据此分析了主蒸汽密度、主蒸汽管道半径对中子能谱计算结果的影响。结果表明,改变电厂运行瞬态不会影响主蒸汽管道室的中子注量分布,而增大主蒸汽管道尺寸则能够有效地降低管道保温材料所受的中子照射,这一结果对今后电厂核设施的辐照影响分析以及放射性评价具有一定的意义。 展开更多
关键词 普贤堆 退役技术 MCNP程序 蒙特卡罗计算方法 中子能谱分析
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离子注入掺杂热再分布的分析计算
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作者 林长贵 王则如 黄宗林 《微电子学与计算机》 CSCD 北大核心 1991年第1期23-25,共3页
本文对离子注入杂质的热再分布过程提出了两种分析手段:其一是已知热再分布的工艺条件,求解扩散方程得到最终杂质分布的解析结果;其二是已知再分布后杂质分布的边界条件,采用牛顿—拉夫逊,蒙特卡罗计算方法,求得最终杂质浓度分布;并给出... 本文对离子注入杂质的热再分布过程提出了两种分析手段:其一是已知热再分布的工艺条件,求解扩散方程得到最终杂质分布的解析结果;其二是已知再分布后杂质分布的边界条件,采用牛顿—拉夫逊,蒙特卡罗计算方法,求得最终杂质浓度分布;并给出了CMOS 集成电路中离子注入p 阱的计算结果. 展开更多
关键词 CMOS集成电路 离子注入 掺杂 热再分布 蒙特卡罗计算方法 数值求解
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Research and development of the automatic modeling system for Monte Carlo particle transport simulation 被引量:58
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作者 吴宜灿 李莹 +7 位作者 卢磊 丁爱平 胡海敏 曾勤 罗月童 郑善良 黄群英 陈义学 《核科学与工程》 CSCD 北大核心 2006年第1期20-27,78,共9页
在广泛调研和分析现有几何建模方法特点的基础上研发了具有可视化用户界面的自动建模程序系统MCAM。它可以实现多种商用软件CAD模型与McNP模型之间的相互转换,且提供了模型建立、预处理、属性分析等基本功能和计算结果可视化及基于医... 在广泛调研和分析现有几何建模方法特点的基础上研发了具有可视化用户界面的自动建模程序系统MCAM。它可以实现多种商用软件CAD模型与McNP模型之间的相互转换,且提供了模型建立、预处理、属性分析等基本功能和计算结果可视化及基于医学映像建模接口等扩展功能。全面系统地介绍了MCAM的设计思想与原理、总体结构、主要功能和国际合作协议框架下的应用测试等情况。实践表明,它是一个实用的MCNP计算辅助工具和核设计与核分析质量保证工具。 展开更多
关键词 MCNP CAD 建模 可视化 蒙特卡罗方法蒙特卡罗粒子输运计算自动建模程序系统的研究与发展
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基于个体传染病模型研究个体行为改变对甲型H1N1的影响
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作者 闫琴玲 肖燕妮 《陕西师范大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第5期1-10,共10页
个体行为在突发性传染病传播过程中起着重要作用,通过行为改变来减缓和控制突发性传染病传播的能力是应对策略的一个重要方面,因此了解个体行为改变如何影响突发性传染病的传播至关重要。基于2009年甲型H1N1流感(A/H1N1)数据,建立基于... 个体行为在突发性传染病传播过程中起着重要作用,通过行为改变来减缓和控制突发性传染病传播的能力是应对策略的一个重要方面,因此了解个体行为改变如何影响突发性传染病的传播至关重要。基于2009年甲型H1N1流感(A/H1N1)数据,建立基于社交网络的个体决策心理模型(LHBM),将个体行为改变率嵌入个体水平的传播动力学模型(IBMs),并研究个体行为改变如何影响A/H1N1的动态变化。然后,基于IBMs,应用基于序列蒙特卡罗的近似贝叶斯计算方法(ABC SMC)估计未知参数。结果表明:IBMs能更准确地描述A/H1N1的传播过程,揭示个体行为改变对A/H1N1暴发的影响。此外,媒体宣传的重点应集中在如何引导个体的行为改变,而且个体的积极响应对于缓解和控制突发性传染病至关重要。 展开更多
关键词 个体行为改变 甲型H1N1流感 个体行为模型 LHBM模型 基于序列蒙特卡罗的近似贝叶斯计算方法
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Study on slope reliability method Response Surface Method based on Morgenstern-Price Method 被引量:5
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作者 RONG Fan CHEN Li +1 位作者 YU Yanxin Tian Shouqi 《Global Geology》 2009年第3期179-182,共4页
The combination of Morgenstern-Price Method (MPM) with Response Surface Method (RSM) improves the eonventional RSM by replacing Finite-Element Method (FEM) with MPM, which is a type of reliability analysis metho... The combination of Morgenstern-Price Method (MPM) with Response Surface Method (RSM) improves the eonventional RSM by replacing Finite-Element Method (FEM) with MPM, which is a type of reliability analysis method-RSM based on MPM, and makes the computing process simpler. The stability of the slope was re-evaluated by use of Monte Carlo method (MCM) and the result contrasted with the fore is the conclusion. The reliability analysis of the artificial slope in Donggang Power Station was carried on, and obtained the reliable charaeteristics, which provided basis for the project. 展开更多
关键词 SLOPE Morgenstern-Price Method response surfaee reliability index Monte Carlo Method
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Calculation model of military aircraft suryiyability to a missile 被引量:1
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作者 杨哲 Li Shulin +2 位作者 Li Shouan Zhou Li Zhang Jun 《High Technology Letters》 EI CAS 2014年第2期117-123,共7页
Since missiles are main threat against aircrafts in air war,a model is proposed for calculating the aircraft survivability to a missile.The hit characteristic of aircraft to a missile is analyzed,and then Monte Carlo ... Since missiles are main threat against aircrafts in air war,a model is proposed for calculating the aircraft survivability to a missile.The hit characteristic of aircraft to a missile is analyzed,and then Monte Carlo method is applied to generate missile detonation location according to its distribution rule.In addition,based on the analysis of fragment trajectory and critical components,the intersection point of these two is determined.Then the kill probability of critical component to a fragment can be calculated,and the aircraft survivability to a missile is obtained accordingly.Finally,the feasibility of the proposed method is demonstrated.Simulation results show that this method captures the basic effects of missile detonation locations on aircraft survivability,which may provide an effective reference to aircraft survivability research. 展开更多
关键词 SURVIVABILITY MISSILE miss distance Monte Carlo kill probability
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A New Alternative Method for Checking Total Stations
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作者 Nikolitsas Konstantinos 《Journal of Civil Engineering and Architecture》 2015年第1期114-120,共7页
Today, just by activating a button on the display panel of a total station, one can measure horizontal and vertical angles or calculate distances and coordinates of points. For this reason, it has become necessary to ... Today, just by activating a button on the display panel of a total station, one can measure horizontal and vertical angles or calculate distances and coordinates of points. For this reason, it has become necessary to improve the check of a total station in order to respond to its contemporary way of use. The aim of this research is to create a new method for checking total stations using only one check--field, in a different way of the today's standards. The basic principle, of the comparison of an instrument's measurements to those of another instrument with higher accuracy, is implemented into a mathematical model such as the adjustment of an indoor geodetic network. Thus, the check of the proper function of a total station is applied. An a-priori calculation Of^o of the network's adjustment can be calculated by modeling the uncertainties using statistical methods as the random number generators by means of the Monte Carlo method. The prospective ao can then be compared to the a-posteriori ao provided by the adjustment of the measurements which are carried out by using the total station under check. 展开更多
关键词 Single control network geodetic network Monte Carlo techniques.
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Simulating Particle Swarm Optimization Algorithm to Estimate Likelihood Function of ARMA(1, 1) Model
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作者 Basad Ali Hussain Al-sarray 《Journal of Mathematics and System Science》 2015年第10期399-410,共12页
This paper present a simulation study of an evolutionary algorithms, Particle Swarm Optimization PSO algorithm to optimize likelihood function of ARMA(1, 1) model, where maximizing likelihood function is equivalent ... This paper present a simulation study of an evolutionary algorithms, Particle Swarm Optimization PSO algorithm to optimize likelihood function of ARMA(1, 1) model, where maximizing likelihood function is equivalent to maximizing its logarithm, so the objective function 'obj.fun' is maximizing log-likelihood function. Monte Carlo method adapted for implementing and designing the experiments of this simulation. This study including a comparison among three versions of PSO algorithm “Constriction coefficient CCPSO, Inertia weight IWPSO, and Fully Informed FIPSO”, the experiments designed by setting different values of model parameters al, bs sample size n, moreover the parameters of PSO algorithms. MSE used as test statistic to measure the efficiency PSO to estimate model. The results show the ability of PSO to estimate ARMA' s parameters, and the minimum values of MSE getting for COPSO. 展开更多
关键词 Particle Swarm Optimization algorithm Likelihood function ARMA(1 1) Model
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Research of Pipeline Pressure Based on the Reliability Theory
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作者 Lihang Wang Pingping Sun 《Journal of Energy and Power Engineering》 2016年第5期292-295,共4页
The former gas pipeline operating pressure transmission determined mostly according to the determined formula into the corresponding pipeline parameters are obtained, and the parameters of the actual pipeline due to m... The former gas pipeline operating pressure transmission determined mostly according to the determined formula into the corresponding pipeline parameters are obtained, and the parameters of the actual pipeline due to many reasons, such as measurement error, production batch, etc., is not a fixed value. This paper on pipeline integrity established limit state equation, using Monte Carlo method to calculate the gas pipeline in different pressures of reliability, according to the API (American Petroleum Institute) 579 recommended target reliability to determine the operating pressure of the different regions, and design coefficient method, the calculated results are compared, results of calculation reliability is more reasonable and improve the delivery pressure of the area, the pipeline safety management provides the basis. 展开更多
关键词 Reliability theory Monte-Carlo method limit state equation operating pressure
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放疗中高次散射X线对剂量计算结果影响分析
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作者 白彦灵 肖雪夫 邵文成 《中华放射肿瘤学杂志》 CSCD 北大核心 2012年第4期384-387,共4页
目的分析放疗中x线的高次散射对剂量计算结果的影响,解决将2次散射光子及高次散射光子对剂量贡献问题修正到1次散射光子散射剂量贡献中的可能性,为建立快速蒙特卡罗剂量计算方法提供支持。方法采用x线与物质的作用截面理论和蒙特卡罗... 目的分析放疗中x线的高次散射对剂量计算结果的影响,解决将2次散射光子及高次散射光子对剂量贡献问题修正到1次散射光子散射剂量贡献中的可能性,为建立快速蒙特卡罗剂量计算方法提供支持。方法采用x线与物质的作用截面理论和蒙特卡罗方法计算结果,分析1次、2次和高次散射X线对剂量计算精确度影响相对重要性。结果≥2次的高次散射对剂量的影响很小,并且可通过一小的修正系数被修正到1次散射X线的贡献中。结论只追踪原射线和1次散射X线剂量贡献就可获得临床满意的剂量计算精确度,如用蒙特卡罗方法建立1次散射x线散射光子注量角分布和光子平均能量散射角分布模型数据库,将有助于提高临床剂量的蒙特卡罗计算效率。 展开更多
关键词 散射X线 蒙特卡罗计算方法 剂量学
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The geometric factor of high energy protons detector on FY-3 satellite 被引量:7
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作者 ZHANG ShenYi ZHANG XianGuo +10 位作者 WANG ChuiQin SHEN GuoHong JIN Tao ZHANG BinQuan SUN YueQiang ZHU GuangWu LIANG JinBao ZHANG XiaoXin LI JiaWei HUANG Cong HAN Ying 《Science China Earth Sciences》 SCIE EI CAS 2014年第10期2558-2566,共9页
Geometric factor is the key parameter for inversion of particle spectrum in space particle detection. Traditional geometric factor is obtained through the method of numerical calculation with the actual structure of t... Geometric factor is the key parameter for inversion of particle spectrum in space particle detection. Traditional geometric factor is obtained through the method of numerical calculation with the actual structure of the detector as the input condition. The degree of accuracy for data inversion is reduced since traditional geometric factor fails to take into account the physical process of interaction between the particle and substance as well as the influence of factors such as the particle interference between different energy channels on the measurement result. Here we propose an improved geometrical factor calculation method, the concept of which is to conduct actual structural modelling of the detector in the GEANT4 program, consider the process of interaction between the particle and substance, obtain the response function of the detector to particles of different energy channels through the method of Monte Carlo simulation, calculate the influence of contaminated particle on the geometrical factor, and finally get the geometrical factors for different energy channels of the detector. The imrpoved geometrical factor obtained through the method has carried out inversion for the data of high energy protons detector on China's FY-3 satellite, the energy spectrum after which is more in line with the power law distribution recognized by space physics. The comparison with the measured result of POES satellite indicates that the FY-3 satellite data are in good accordance with the satellite data, which shows the method may effectively improve the quality of data inversion. 展开更多
关键词 geometrical factor response function particle radiation space detection FY-3
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Efficient implementation of the Barnes-Hut octree algorithm for Monte Carlo simulations of charged systems 被引量:1
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作者 GAN ZeCheng XU ZhenLi 《Science China Mathematics》 SCIE 2014年第7期1331-1340,共10页
Computer simulation with Monte Carlo is an important tool to investigate the function and equilibrium properties of many biological and soft matter materials solvable in solvents.The appropriate treatment of long-rang... Computer simulation with Monte Carlo is an important tool to investigate the function and equilibrium properties of many biological and soft matter materials solvable in solvents.The appropriate treatment of long-range electrostatic interaction is essential for these charged systems,but remains a challenging problem for large-scale simulations.We develop an efficient Barnes-Hut treecode algorithm for electrostatic evaluation in Monte Carlo simulations of Coulomb many-body systems.The algorithm is based on a divide-and-conquer strategy and fast update of the octree data structure in each trial move through a local adjustment procedure.We test the accuracy of the tree algorithm,and use it to perform computer simulations of electric double layer near a spherical interface.It is shown that the computational cost of the Monte Carlo method with treecode acceleration scales as log N in each move.For a typical system with ten thousand particles,by using the new algorithm,the speed has been improved by two orders of magnitude from the direct summation. 展开更多
关键词 ELECTROSTATICS Monte Carlo fast algorithms OCTREE colloidal interfaces
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《(整数值)随机数的产生》教学设计与实践
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作者 张卓颖 《中小学数学(高中版)》 2008年第5期20-24,共5页
今年3月,笔者认真学习了"中学数学核心概念与思想方法教学设计研究"的部分成果,设计了《(整数值)随机数的产生》一课,参加广东省中学青年数学教师优秀课评比活动并取得了特等奖.下面结合自己的教学实践,谈谈对该部分内容的初... 今年3月,笔者认真学习了"中学数学核心概念与思想方法教学设计研究"的部分成果,设计了《(整数值)随机数的产生》一课,参加广东省中学青年数学教师优秀课评比活动并取得了特等奖.下面结合自己的教学实践,谈谈对该部分内容的初步认识. 展开更多
关键词 蒙特卡罗方法计算 伪随机数 模拟试验 古典概型 教学设计研究 概率模型 随机事件 概率估计 整数值 计算
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