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1 本节课教学内容的本质、地位、作用分析分类加法计数原理与分步乘法计数原理是人类在大量的实践经验的基础上归纳出的基本规律,它们不仅是推导排列数、组合数计算公式的依据,而且其基本思想方法也贯穿在解决本章应用问题的始终,在本章中是奠基性的知识.返璞归真的看两个原理,它们实际上是学生从小学就开始学习的加法运算与乘法运算的推广. 相似文献
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主要研究垃圾文本识别问题,利用苹果手机评论文本特征向量建立了SVM分类模型对垃圾文本进行识别,并与BP神经网络判别模型结果进行对比,得出苹果手机前400组训练样本的判别正确率为71%,后196组测试样本的判别正确率为70.12%.故得到,影响垃圾观点文本识别效果的主要原因为:1)评论文本的特征项的提取和文本特征空间向量求解.2)判别分类方法的选择,其中SVM文本识别效果最优. 相似文献
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在听到要开设一节“分类计数原理与分步计数原理”的南京市公开课的时候,我们很踌躇,因为非常担心这个内容能否上出什么新意来.我们先找了一些比较时髦的例题进行了教学的难易加工和情境设置,但是按照先引入原理再例题讲解的思路,总觉得缺少什么,没有创作的激情和灵感的冲动.考虑到笔者所带的教学班级是文科重点班,学生热爱写作,思维活跃,数学基本功比较扎实,也有小组合作学习的经历,因此我们尝试着借鉴文学创作的一些手法进行一次数学课堂的教学设计. 相似文献
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一、教材分析
1教材的地位与作用
本节课教学内容是《分类加法计数原理与分步乘法计数原理》,是人数A版数学选修2-3第一章第一节内容.这两个原理是本章的重点基础知识,一方面它为后面学习排列、组合、随机变量的概率等内容提供了思想和理论依据,是学习排列组合e的基础;另一方面它的结论与其基本思想方法在解决本章应用问题时有许多直接应用,因此,它理应成为我们重点把握的教学内容. 相似文献
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讨论露天矿生产的车辆调度问题,关键是如何分配和调度现有条件下的电铲和卡车,从而得到一个好的生产计划.通过对问题的进一步分析和合理的简化,根据总定量最小原则及产量最大原则分别建立了相应的动态规划模型.由于模型在解决具体问题过程中的复杂程度和变量、不等式约束条件的个数太多等原因,我们采用逐步优化法对模型作了进一步的改进,然后用LINGO、LINDO等数学软件编程进行模型求解,得到了根据总定量最小原则及产量最大原则下的计划方案. 相似文献
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鉴于新企业对经济发展的推动作用,本文利用负二项同归模型对企业影响因素进行研究,实证研究表明出市场准入门槛、最优经济规模等影响因素外,产业集聚状况对新企业进入只有积极影响,而且产业集聚区的企业规模及产业集聚区所在地的城市化水平均对新企业活动产生影响。 相似文献
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王海军 《数学的实践与认识》2017,(2):142-147
遥感影像分类作为遥感技术的一个重要应用,对遥感技术的发展具有重要作用.针对遥感影像数据特点,在目前的非线性研究方法中主要用到的是BP神经网络模型.但是BP神经网络模型存在对初始权阈值敏感、易陷入局部极小值和收敛速度慢的问题.因此,为了提高模型遥感影像分类精度,提出采用MEA-BP模型进行遥感影像数据分类.首先采用思维进化算法代替BP神经网络算法进行初始寻优,再用改进BP算法对优化的网络模型权阈值进一步精确优化,随后建立基于思维进化算法的BP神经网络分类模型,并将其应用到遥感影像数据分类研究中.仿真结果表明,新模型有效提高了遥感影像分类准确性,为遥感影像分类提出了一种新的方法,具有广泛研究价值. 相似文献
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函数在实际生活中有广泛的应用,用数学眼光观察后所形成的函数应用问题也呈现出五彩缤纷的画面,应用问题的分类方法很多,本文按照新课程所涉及的内容,从函数本身的特点入手,将其具体分类细化,然后分析其特点,研究其数学本质与代数结构,以期对函数实际应用模型有所突破,提升综合分析能力与水平. 相似文献
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SOLO译为“可观察到学习结果的结构”,它是由澳大利亚教育心理学家约翰·比格斯提出的一种质性评价认知发展阶段的理论.本文主要结合了目前高中对基本计数原理的学习,就SOLO理论对其在高中数学教学中的应用进行了分析. 相似文献
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基于第十一届"华为杯"全国研究生数学建模竞赛E题第五问,针对一类多车型多目的地的整车物流运输调度问题,先直接计算完成总任务所需的车辆数来阐明该题的最优解的下界限为113辆,再对原始数据进行预处理,基于对乘用车的分类与排样算法,筛选出每种轿运车的M种装载方案代表,再对目的地位置及结合各目的地的任务需求,确定出3条不绕行路线,根据启发式调整优化算法,并以轿运车使用量最少及总行驶里程最短为优化目标,建立了多目标整数规划模型进行求解,最优可行解为114辆,其中1-1型91辆,1-2型18辆,2-2型5辆. 相似文献
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It is shown that each semispaceC X naturally generates a relation of complete preorder onX with respect to which the pair (X C, C) is a cut ofX. By identifying the type of the semispace with the type of the cut generated by this semispace, the semispaces are classified according to their types. The obtained classification extends the classification of semispaces in finite-dimensional vector spaces due to Martinez-Legaz and Singer to infinite-dimensional spaces.Translated fromMatematicheskie Zametki, Vol. 64, No. 2, pp. 191–198, August, 1998. 相似文献
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AbstractIn this article, our main aim is to develop gap functions and error bounds for a (non-smooth) convex vector optimization problem. We show that by focusing on convexity we are able to quite efficiently compute the gap functions and try to gain insight about the structure of set of weak Pareto minimizers by viewing its graph. We will discuss several properties of gap functions and develop error bounds when the data are strongly convex. We also compare our results with some recent results on weak vector variational inequalities with set-valued maps, and also argue as to why we focus on the convex case. 相似文献
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In this article, gap functions for a generalized vector equilibrium problem (GVEP) with explicit constraints are investigated. Under a concept of supremum/infimum of a set, defined in terms of a closure of the set, three kinds of conjugate dual problems are investigated by considering the different perturbations to GVEP. Then, gap functions for GVEP are established by using the weak and strong duality results. As application, the proposed approach is applied to construct gap functions for a vector optimization problem and a generalized vector variational inequality problem. 相似文献
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《Optimization》2012,61(9):1339-1352
In this article, by using the image space analysis, a gap function for weak vector variational inequalities is obtained. Its lower semicontinuity is also discussed. Then, these results are applied to obtain the error bounds for weak vector variational inequalities. These bounds provide effective estimated distances between a feasible point and the solution set of the weak vector variational inequalities. 相似文献
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度量空间中的软间隔分类 总被引:1,自引:0,他引:1
本文研究了度量空间中的软间隔分类问题,利用度量d的特性,得到一非线性映射,将度量空间等距嵌入Banach空间中,并构造了一种软间隔分类算法. 相似文献
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In this paper, the image space analysis is applied to investigate scalar-valued gap functions and their applications for a (parametric)-constrained vector variational inequality. Firstly, using a non-linear regular weak separation function in image space, a gap function of a constrained vector variational inequality is obtained without any assumptions. Then, as an application of the gap function, two error bounds for the constrained vector variational inequality are derived by means of the gap function under some mild assumptions. Further, a parametric gap function of a parametric constrained vector variational inequality is presented. As an application of the parametric gap function, a sufficient condition for the continuity of the solution map of the parametric constrained vector variational inequality is established within the continuity and strict convexity of the parametric gap function. These assumptions do not include any information on the solution set of the parametric constrained vector variational inequality. 相似文献
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本文给出了模糊拓扑向量空间(X,W)到(Y,J)的函数族F上的模糊线性拓扑,证明了若值域空间(Y,J)是(Q)型的、局部凸的模糊拓扑向量空间,则(F,),也是型的、局部凸的模糊拓扑向量空间。 相似文献
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Yu. V. Goncharov I. B. Muchnik L. V. Shvartser 《Computational Mathematics and Mathematical Physics》2008,48(7):1243-1260
An algorithm for selecting features in the classification learning problem is considered. The algorithm is based on a modification of the standard criterion used in the support vector machine method. The new criterion adds to the standard criterion a penalty function that depends on the selected features. The solution of the problem is reduced to finding the minimax of a convex-concave function. As a result, the initial set of features is decomposed into three classes—unconditionally selected, weighted selected, and eliminated features. Original Russian Text Yu.V. Goncharov, I.B. Muchnik, L.V. Shvartser @, 2008, published in Zhurnal Vychislitel’noi Matematiki i Matematicheskoi Fiziki, 2008, Vol. 48, No. 7, pp. 1318–1336. 相似文献