ISBN: (纸本)9787111642602

关键词： Temperature  

摘要： Abstract: This article proposes an algorithm for solving the modeling problem with numerous variables in the MATLAB programming language. According to the developed algorithm, the MATLAB model calculates the values of solar insolation and ambient temperature of a particular location depending on five variables simultaneously: (1) time of day (τ), (2) day of the year (n), (3) tilt angle (β), (4) azimuth angle (γ) and (5) albedo (ρ). Meanwhile, the calculation results form a multidimensional database of solar insolation and ambient temperature of a given location for any values of the above variables and their *** example of using the created database is given for calculating the annual total photovoltaic panel productivity and productivity dynamics on days of the year for latitude 41°2995′, which corresponds to a location in the city of Tashkent. The developed algorithm can be used to analyze/forecast the efficiency of solar plants using parameters from the database and other variables, such as temperature coefficient, dust content, nominal efficiency, wind speed, humidity, etc., as input data. The availability of data makes it possible to use data for both one-way and two-way reception of radiation as for bifacial photovoltaic panels. The database created based on the proposed program model can serve as a basis for comparison with other calculations or measurement databases and for studying or determining other parameters that affect possible differences in the compared data and creating advanced modeling algorithms for the solar irradiance. © 2020, Allerton Press, Inc.

关键词： 价值转移   数学算法   互联网领域   参与方   架构   信任   链  

摘要： 区域链之所以能够做很多事情,是因为区域链具有价值转移和信用转移的优势.这是一种通过数学算法来实现的"去信任"架构."去信任"架构就是系统中的参与方无须信任对方就可以完成交易和协作.这是传统互联网领域中最薄弱的一个环节.

关键词： 数学建模   改进遗传算法   最小二乘法   拟合  

摘要： 研究计算机数学建模中改进遗传算法与最小二乘法的具体应用。针对基本遗传算法中存在的数据冗余问题,提出了一种改进遗传算法,结合最小二乘法建立计算机数学模型,以更好的应对数据变化。对具体的问题进行计算机数学建模,并进行验证,结果表明改进后的遗传算法具有一定的辨识能力,寻找最优,大大提高了工作效率。利用MATLAB软件求解方程组,确定参数的使用范围,解决估算参数范围和辨识问题。仿真结果证明改进后的遗传算法与最小二乘法结合后建立数学模型,大大增加了个体搜索空间,比基本遗传算法提高了90%的运算率。

关键词： 计算教学   对比   算理   算法  

摘要： 《义务教育数学课程标准(2011年版)》将"运算能力"作为十个核心词之一,足见计算学习在数学教学中的重要性。本文以苏教版数学一年级下册"两位数加整十数、一位数(不进位)"为例,着重通过三个层次的对比,让学生感受多种算法,既有效地沟通了算理与算法之间的联系,同时又使学生加深了对计算方法的认识。

关键词： 数学思想   计算机编程   算法优化  

摘要： 本文结合编程教学实践,立意于研究计算机编程中数学思想对算法的优化性,通过对比实验数据,验证数学思想在算法优化中的重要作用,总结出数学思想优化算法的策略,以期编程学习者能养成运用数学思想优化算法的意识,提高算法效率。

关键词： 高中数学   算法教学   教学原则   策略  

摘要： 随着现代计算机信息技术的发展,计算机语言的“灵魂”―算法,也被注入引入到高中数学新课程教学中。算法在高中数学教学中的引入,对培养学生的逻辑思维能力、创新思维能力和自主探索能力都有着极其重要的教学意义。同时,也为学生今后的继续学习和工作实践奠定了一定的计算机知识基础。因此,在高中数学教学中,正视算法在高中数学教学中定位,革新传统教学方法是教研人员应积极探索和研究的重要课题。

关键词： Radioactive   Nuclide   Decay   Modeling  

摘要： Radioactive decay processes, such as alpha decay, produce decay chains where the mass numbers of nuclides decrease as larger nuclides expel energetic particles to form smaller nuclides. Under these conditions, the coefficient matrix that describes the differential rate expressions for radioactive decay can be made lower triangular. With this special structure, formulating an algebraic solution to the decay chains can be done by first formulating the eigenvectors that make up the coefficient matrix, which can then be solved using forward substitution for a lower triangular matrix. This work details the derivation of algebraic solutions for decay chains of any number of stable and unstable nuclides with any number of branching based on this eigenvector analysis. A prototype computational code was developed to validate and compare this methodology against a number of other methods for solving similar systems. A two-phase sorting algorithm yielding the lower triangular matrix structure was established to apply the developed algebraic solutions for decay chains involving beta-emitting radionuclides transformed into daughter nuclides without change in their mass number. The methodologies produced in this work provide an efficient way to estimate nuclide fractions from natural decay processes. (C) 2019 Elsevier B.V. All rights reserved.