多方位变式训练 方可熟练定位

对于几何概型,关键是要构造出随机事件对应的几何图形,利用图形的几何度量来求随机事件的概率.所以解答几何概型类的题型都要涉及对图形的观察、思考与定位,以便获得表示区域Ω的几何度量μΩ与表示子区域A的     

准确定位 掌握二项分布题型解题要领

一、二项分布题型定位1.明确二项分布定义在n次独立重复试验中,设事件A发生的次数为X,在每次试验中事件A发生的概率为p,那么在n次独立重复试验中,事件A恰好发生k次的概率为P（X=k）=C_n^kP^k（1-p）^n-k（k=0,1,2,…,n）,此时称随机变量X服从二项分布,记作X～B（n,p）,并称p为成功概率.     

宇宙中有趣的多星模型问题

现代实验观测表明,在天体运动中,将两颗彼此距离较近而绕同一点做圆周运动的行星称为双星模型.类比多星问题又是指彼此相互依存和相互作用而围绕某一点作圆周运动的行星.由于多星间的引力和运动情况相当保持不变,将出现很多有趣的现象.     

“用分数表示可能性的大小”教学设计与反思

教学内容: 义务教育课程标准实验教科书苏教版数学六年级上册第94 ～96页例1、例2及相应的“试一试”“练一练”,练习十八第1～2题. 教学目标: 1.让学生初步理解并掌握用分数表示可能性大小的基本思考方法,会用分数表示简单事件发生的可能性,进一步加深对可能性大小的认识.     

3DV quality model based depth maps for view synthesis in FTV system

Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems.When depth maps are derived using existing depth estimation methods,the depth distortions will cause undesirable artifacts in the synthesized views.To solve this problem,a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed.First,the relationships between distortions in coded depth map and rendered view are derived.Then,a precisely 3DV quali...     

Function oriented service composition modeling

Formal models for service composition have been proposed with the variation of the requirements of service developers. Some famous models have provided checking and verification techniques and tools for the behavior of service composition. These models generally focus much on the message flow of web services and neglecting the data contained in the exchanged messages among services, which restrict the application range of these models and also the web service techniques. As new kind of services with different protocols and communication methods have appeared, it is needed to model service composition from a new view which is adapted to the new development in service area. In this paper we offer a function oriented model of service composition which treats the composite service as a software system and specify the function of services which can be directly used to the realization by service providers.     

Research and implementation of scalable parallel computing based on Map-Reduce

As a parallel programming model, Map-Reduce is used for distributed computing of massive data. Map-Reduce model encapsulates the details of parallel implementation, fault-tolerant processing, local computing and load balancing, etc., provides a simple but powerful interface. In case of having no clear idea about distributed and parallel programming, this interface can be utilized to save development time. This paper introduces the method of using Hadoop, the open-source Map-Reduce software platform, to combine PCs to carry out scalable parallel computing. Our experiment using 12 PCs to compute N-body problem based on Map-Reduce model shows that we can get a 9.8x speedup ratio. This work indicates that the Map-Reduce can be applied in scalable parallel computing.     

给学校仪式加点料

仪式作为一种文化或者说文化象征,具有特别重要的作用．它可以使一些我们所经历的看似普通的事件被赋予一种特别的甚至是无法言说的意义,直至触及人的心灵。仪式作为学校文化的重要载体,需要教育人善于从一些普通事件中充分挖掘出仪式的价值来．让师生经历共同的情感体验．使普通的事件成为不普通的经历,激发师生对学校文化价值观的认同和欣赏,使学校成为师生共同的精神家园。     

3D打印全民DIY时代来临

近年来,"3D"这个概念在全球范围内火得一塌糊涂,相对于大多数的3D产品还仅仅停留在模拟视觉效果上,看得见而摸不着,3D打印机的上市,却是真正将平面图形打印成实物,看得见摸得着并且还能使用。去年底,全球首辆利用3D打印技术制造的汽车面世。它实际上是种利用光固化和纸层叠等技术的快速成型装置。这辆叫作Urbee的双座汽车包括玻璃嵌板在内的所有外部组件,都是通过Stratasys公司的大型3D打印设备生产而成。由于3D打印技术不需要设计者使用工具和通过机械或者手工进行加工,修改设计细节时只需要在电脑里操作,非常方便。Urbee用电     

事件

唇美润彩炫目亮相屈臣氏这个冬天,如何让双唇散发迷人光彩?曼秀雷敦Lip Beaut唇美润彩唇畜炫目亮相屈臣氏!彩特+护