基于嵌入式操作系统编程实现加乘常数和周期误差检定计算

文章介绍了基于嵌入式操作系统Mobile6.0编程实现加乘常数和周期误差检定计算的方法,描述了Mobile6.0的技术特性、加乘常数与周期误差的数学基础,详细说明了软件的操作流程,并对在嵌入式设备上进行测绘软件的开发作了展望。     

Cl2-,O2-和N2-的势能函数研究

本文采用从头计算的方法对Cl2-,N2-和O2-的势能函数进行了数值计算,采用最小二乘法拟合出了Murrell-Sorbie势能函数的参数,并根据拟舍出的参数值求出力常数和光谱数据.     

基态MgB的势能函数研究

用密度泛函理论B3LYP方法和6-311+G(2DF)基函数对基态MgB分子的势能函数进了数值计算,采用最小二乘法拟合出了Murrell-Sor-bie势能函数的参数,并根据拟合出的参数值计算出力常数和光谱数据。     

走向“理解”的数学教学——《两位数乘一位数（不进位）》教学设计与评析

1．使学生经历探索整十数乘一位数的口算方法和不进位的两位数乘一位数笔算方法的过程,理解并掌握计算方法,能正确进行计算。知道可以用再乘一遍的方法进行乘法验算。     

用ab initio方法研究NaH(NaD)分子的结构及其基态(X1∑+)的势能函数

运用群论和原子分子静力学方法,推导了NaH(NaD)分子基态的合理离解极限.采用两种方法和三种基组优化计算了NaH(NaD)分子基态的平衡结构和离解能.选用电子相关单双取代耦合簇CCSD(T)方法结合6-311 G(3df,3pd)基组对NaH(NaD)分子基态进行了单点能扫描计算.用最小二乘法拟合Murrell-Sorbie 函数,计算得到了NaH(NaD)分子基态的势能函数和对应的光谱常数.结果表明, 采用Murrell-Sorbie函数计算所得的光谱常数与实验结果符合的很好,能精确地描述NaH(NaD)分子基态的势能函数.     

运算法则需要“立体”建构——由《分数乘分数》教学引发的思考

这是"分数乘分数"课前的一次调查:计算下面各题:(1)1/5×1/4;(2)1/5×3/4;(3)2/3×4/5。从计算结果我们发现,两个班分别有50%和53.8%的学生"会"计算"分数乘分数"式题。那么是否可以这样说,关于"分数乘分数"的计算,班中有一半学生是不用"教"的?于是我们对学生在计算以上式题中所采用的计算方法进行了分类     

三维坐标法在变形监测中的应用

基于在变形监测中全站仪的使用,利用全站仪能同时观测角度、距离和高程的特点,针对施工场地狭窄,无法运用传统方法进行变形监测的情况卞,对深基坑的变形监测提出了三维坐标法。通过观测变形点的坐标变化,计算出变形监测点的水平位移和沉降量。     

《三位数乘两位数》教学设计与意图说明

【教学内容】四年级(下册)第1～2页例题、"想想做做"第1～4题。【教学目标】1.使学生经历探索三位数乘两位数笔算方法的过程,理解三位数乘两位数的算理,掌握三位数乘两位数的笔算方法,能正确进行计算。2.使学生在探索计算方法的过程中体会新旧知识间的联系,并能将三位数乘两位数的一般方法迁移到多位数的乘法中去。     

以教材为本活用教材以思想为魂渗透思想——以“分数乘整数”教学为例

1．学生在自主探索的基础上,理解分数乘整数的意义与算理,能够熟练地进行计算。2．学生在合作学习和互动交流中,探索、发现并归纳总结出分数乘整数的计算方法。     

基本物理常数的1986年国际推荐值

基本物理常数是指自然界中的一些普适常数,它们不会受时间、地点和环境条件的影响而发生变化。基本物理常数的数值可以通过不同的方法进行直接测量或间接测量。为使不同方法获得的各个常数数值构成一个内部向洽的体系,即具有总体一致性,伯奇于1929年首先创立了基本物理常数的最小二乘法平差的方法.国际科技数据委员会(简称CODATA)所属的基本常数任务组于1973年进行一次新的基本常数平差,得出一组基本常数的国际推荐值。由于基本常数精密测量工作不断取得进展,许多常数出现新     

多元函数条件极值的计算举例

多元函数的条件极值有多种算法。该文以举例的方式,总结介绍多元函数条件极值的几种初等计算方法及拉格朗日乘数法。     

三坐标测量机动态误差的分析和测量(英文)

对三坐标测量机动态误差的分析和计算方法进行讨论．为将线位移误差和转角误差联系起来,提出一种由转角误差得到测头线位移误差的方法,还用有限元法建立动态误差的模型．此外,用电感测微仪对动态转角误差进行了测量．     

多元函数在一元微积分中的一些应用

举例说明了如何把多元函数的一些性质应用于解决一元微积分的问题中.如用多元函数的偏导解决一元隐函数的求导问题,用多元函数的拉格朗日乘数法来求一元函数的极值,用二重积分求平面图形的面积,三重积分求旋转体的体积等等.     

用诱导效应传递率计算化学位移值——烷烃衍生HNMR物化学位移

本文作者提出了增加电子对影响诱导效应传递的计算方法,以及用诱导传递计算化学位移值的公式,结果与文献值比较,误差较小。     

What do spelling errors tell us? Classification and analysis of errors made by Greek schoolchildren with and without dyslexia

In this study we propose a classification system for spelling errors and determine the most common spelling difficulties of Greek children with and without dyslexia. Spelling skills of 542 children from the general population and 44 children with dyslexia, Grades 3–4 and 7, were assessed with a dictated common word list and age-appropriate passages. Spelling errors were classified into broad categories, including phonological (graphophonemic mappings), grammatical (inflectional suffixes), orthographic (word stems), stress assignment (diacritic), and punctuation. Errors were further classified into specific subcategories. Relative proportions for a total of 11,364 errors were derived by calculating the opportunities for each error type. Nondyslexic children of both age groups made primarily grammatical and stress errors, followed by orthographic errors. Phonological and punctuation errors were negligible. Most frequent specific errors were in derivational affixes, stress diacritics, inflectional suffixes, and vowel historical spellings. Older children made fewer errors, especially in inflectional suffixes. Dyslexic children differed from nondyslexic ones in making more errors of the same types, in comparable relative proportions. Spelling profiles of dyslexic children did not differ from those of same-age children with poor reading skills or of younger children matched in reading and phonological awareness. In conclusion, spelling errors of both dyslexic and nondyslexic children indicate persistent difficulty with internalizing regularities of the Greek orthographic lexicon, including derivational, inflectional, and word (stem) families. This difficulty is greater for children with dyslexia.     

Exploratory analyses to improve model fit: Errors due to misspecification and a strategy to reduce their occurrence

Two Lagrange multiplier (LM) methods may be used in specification searches for adding parameters to models: one based on univariate LM tests and respecification of the model (LM‐respecified method) and the other based on a partitioning of multivariate LM tests (LM‐incremental method). These methods may result in extraneous parameters being included in models due to either sampling error or the model being misspecified. A 2‐stage specification search may be used to reduce errors due to misspecification. In the 1st stage, parameters are added to models based on LM tests to maximize fit. Second, parameters added in the 1st stage are deleted if they are no longer necessary to maintain model fit. Illustrations are presented to demonstrate that errors due to misspecification occur with the LM‐respecified method and are even more likely with the LM‐incremental approach. These illustrations also show how the deletion stage can help eliminate some of these errors.     

复数法计算平面低副机构运动误差的精确度分析

本文从理论上对参考文献[1]中导出的运动误差分析通用公式的计算误差进行了分析,并通过实例加以比较,指出了应用该通用公式对平面低副机构运动误差进行分析有足够的计算精确度,完全能够满足实际工程的需要。     

工件的定位误差分析及计算方法

分析了定位误差的概念及产生原因,给出了定位误差的5种计算方法：矢量合成法,几何分析法、图解法、全微分法、尺寸链法,为正确选择定位误差的计算方法提供了依据。     

基于离散余弦变换的脆弱水印智能优化算法

基于离散余弦变换的脆弱数字水印计算过程中,由于浮点数-整数转换过程舍入误差造成影像峰值信噪比(PSNR)降低,提取水印标准互相关相似度(NC)低,采用遗传算法、克隆选择算法等智能优化算法,可以修正变换过程产生的舍入误差,提高基于离散余弦变换的脆弱数字水印的性能。并且这一思路能够进一步用在其他数字水印技术中,采用智能算法来修正某些关键计算步骤引入的舍入误差。     

Impact of Design Effects in Large-Scale District and State Assessments

This article proposes that sampling design effects have potentially huge unrecognized impacts on the results reported by large-scale district and state assessments in the United States. When design effects are unrecognized and unaccounted for they lead to underestimating the sampling error in item and test statistics. Underestimating the sampling errors, in turn, results in unanticipated instability in the testing program and an increase in Type I errors in significance tests. This is especially true when the standard error of equating is underestimated. The problem is caused by the typical district and state practice of using nonprobability cluster-sampling procedures, such as convenience, purposeful, and quota sampling, then calculating statistics and standard errors as if the samples were simple random samples.