教学课程资源库 更多>>

关键词： 分析解决问题   培养   策略  

摘要： 分析和解决问题的能力是指能阅读、理解对问题进行陈述的材料；能综合应用所学数学知识、思想和方法解决问题，包括解决遭相关学科、生产、生活中的数学问题，并能用数学语言正确地加以表述。它是逻辑思维能力、运输能力、空间想象能力等基本数学能力的综合体现。现就分析和解决问题能力的组成绩培养谈几点刍见。

关键词： 放射科   新品推介会   中国医疗器械行业协会   矩阵   数学分析   影像设备   DR  

摘要： 2014年4月17日,来自全国各地近二百名的医疗届精英齐聚深圳迎宾馆,参加开普2014新品推介会,本次推介会开普医疗正式推出X线摄影全新理念性产品"百变DR",掀起了放射科的矩阵革命。中国医疗器械行业协会副会长姜峰先生作为嘉宾出席了本次推介会,并在会上致辞。辽宁开普医疗系统有限公司(以下简称"开普医疗")植根于辽宁省本溪市药都经济开发区。企业成立以来,一直致力于核磁共振成像系统、数字化X射线摄影系统等大型医疗影像设备、相关医用图像处理软件、影像设备升级解决方案及服务。本着"用心感知客户需求、静心、精心做好产品"的服务理念,将科技创新与用户临床需求糅合在一起,不断的开发新品。本次借助71届中国国际医疗器械博览会的东风,诚意推出革命性产品"百变DR",打破普放设备的应用瓶颈。

关键词： Algorithms   Models, Theoretical  

摘要： The calibration coefficients of two commercial anemometers equipped with different rotors were studied. The rotor cups had the same conical shape, while the size and distance to the rotation axis varied. The analysis was based on the 2-cup positions analytical model, derived using perturbation methods to include second-order effects such as pressure distribution along the rotating cups and friction. The comparison with the experimental data indicates a nonuniform distribution of aerodynamic forces on the rotating cups, with higher forces closer to the rotating axis. The 2-cup analytical model is proven to be accurate enough to study the effect of complex forces on cup anemometer performance.

关键词： 数学问题   培养学生   解题方法   发散思维能力   一题多解   学习效率   数学分析   创新能力   宽度   函数  

摘要： 认真研究数学中的一题多解,有利于拓展学生的思维宽度.在解决高中数学问题时,从不同的角度探索解题方法能培养学生的发散思维能力,同时,还能提高他们的学习效率,有效地培养学生的数学分析和创新能力.下面赏析一道函数题,探索数学解题方法的多样化.

关键词： 潮流计算   电力系统计算   电力系统潮流   软件   非线性代数方程   非线性方程   电力电子元件   系统元件   短路计算   元件模型   计算机算法   潮流分布   手算方法   电力系统分析   谐波分析   数学分析  

摘要： 所谓电力系统潮流就是指电力系统运行时各节点以及各电气设备的电压、电流和功率。潮流计算是电力系统分析中采用的一种最基本的电气运算,同时也是研究电力系统的运行以及规划方案的重要手段,其本质是求解一组多元非线性代数方程。电力系统潮流计算具有很重要的现实意义:可以合理规划电网中的电源容量和电源接入点以及确定最佳的电网架构;可以找出电网中因为负荷增长和新设备投入而导致的薄弱环节,方便对电网进行网架结构的改进以及基建的加速

关键词： Asymmetric competition   continuous-time modelling   fire   Non-standard numerical scheme   qualitative analysis   Savanna  

摘要： Several continuous-time tree-grass competition models have been developed to study conditions of long-lasting coexistence of trees and grass in savanna ecosystems according to environmental parameters such as climate or fire regime. In those models, fire intensity is a fixed parameter while the relationship between woody plant size and fire-sensitivity is not systematically considered. In this paper, we propose a mathematical model for the tree-grass interaction that takes into account both fire intensity and size-dependent sensitivity. The fire intensity is modeled by an increasing function of grass biomass and fire return time is a function of climate. We carry out a qualitative analysis that highlights ecological thresholds that summarize the dynamics of the system. Finally, we develop a non-standard numerical scheme and present some simulations to illustrate our analytical results. [ABSTRACT FROM AUTHOR]

关键词： 矩阵   数学分析   品牌机   DIY   MX   MatriMax G-MX7   极限   性价比  

摘要： G-MX7是来自由英特尔、微星、英伟达联手打造的品牌——"MatriMax"(极限矩阵)旗下的产品。作为剑指高端游戏玩家的游戏台式电脑,G-MX7的表现值得我们期待吗?作为一款定位高端的游戏台式电脑,G-MX7机箱的样式稍显老旧,不如Alienware旗下产品那般炫酷,但真材实料的0.8mm镀锌钢板以及14.5kg的重量,足以印证该产品没有在设计用材

关键词： MATHEMATICAL analysis   HIV infections   MATHEMATICAL models   COMMUNICABLE diseases   LYAPUNOV functions   DIFFERENTIAL equations  

摘要： This paper aims to study the dynamics of new HIV (the human immunodeficiency virus) models with switching nonlinear incidence functions and pulse control. Nonlinear incidence functions are first assumed to be time-varying functions and switching functional forms in time, which have more realistic significance to model infectious disease models. New threshold conditions with the periodic switching term are obtained to guarantee eradication of the disease, by using the novel type of common Lyapunov function. Furthermore, pulse vaccination is applied to the above model, and new sufficient conditions for the eradication of the disease are presented in terms of the pulse effect and the switching effect. Finally, several numerical examples are given to show the effectiveness of the proposed results, and future directions are put forward. © 2014 Xiying Wang et al.

关键词： HALL effect   UNSTEADY flow (Fluid dynamics)   PERMEABILITY   POROUS materials   MAGNETIC fields   VISCOUS flow   MATHEMATICAL analysis  

摘要： This paper proposes the exact solution for unsteady flow of a viscous incompressible electrically conducting fluid past a impulsively started infinite horizontal surface which is rotating with an angular velocity embedded in a saturated porous medium under the influence of strong magnetic field with hall effect. Our study focuses on the change of direction of the external magnetic field on the flow system which leads to change in the flow behavior and skin frictional forces at the boundary. Systems of flow equations are solved using Laplace transform technique. The impacts of control parameters Hartman number, rotation of the system, hall effect, inclination of the magnetic field, and Darcy number on primary and secondary velocities are shown graphically, skin friction at horizontal boundary in tabular form. For validating our results, in the absence of permeability of the porous medium and inclination of the magnetic field the results are in good agreement with the published results.

关键词： 吉林工商学院   实证分析   省际面板数据   吉林省   灰色关联分析   数学分析   研究述评   旅游人才培养   产业集聚   学报   连续出版物   目录   检索工具