基于Div+CSS布局方式的研究

DIV+CSS作为一种全新的网页排版布局方法,其与早期的表格布局方式完全不同,使用DIV+CSS排版布局能够使网页真正做到Web标准中所要求的网页内容与表现完全分离,从而提高了网站的维护的效率,使得操作起来更加方便快捷。据统计,目前绝大多数的网站都已开始使用DIV+CSS布局进行网页制作。文章力求通过简单易懂的表述方式,与大家一起探讨使用Web标准进行网页设计制作的各方面知识和技巧。     

Web前端开发技术以及优化方向

在我国经济高速发展的背景下,信息技术也在飞速发展,近些年来互联网及其相关技术已经深入影响到了我们生产生活的各个方面,成为了当今社会不可或缺的一部分。前端开发技术是互联网技术中非常重要的一个环节,是创建Web页面或app等前端界面呈现给用户的过程,通过HTML,CSS及JavaScript以及衍生出来的各种技术、框架、解决方案,来实现互联网产品的用户界面交互。它从网页制作演变而来,名称上有很明显的时代特征。在互联网的演化进程中,网页制作是Web1.0时代的产物,早期网站主要内容都是静态,以图片和文字为主,用户使用网站的行为也以浏览为主。随着互联网技术的发展和HTML,CSS3的应用,现代网页更加美观,交互效果显著,功能更加强大。Web前端技术对于互联网技术的长期运营以及今后在新型技术手段下的长远发展有着深远的影响,文章对网络前端的开发技术以及将来的优化方向进行了探讨。     

网页特效设计

想让你的网页动起来?想让你的网页更具交互性?听好喽-- 翻滚图的制作 动态网页技术中,翻滚图是比较简单的,但它的效果却非常明显,因此常常可以在各大网站见到这种效果.     

动感即生命网页特效设计

想让你的网页动起来?想让你的网页更具交互性?听好喽-- 翻滚图的制作 动态网页技术中,翻滚图是比较简单的,但它的效果却非常明显,因此常常可以在各大网站见到这种效果.     

DIV+CSS技术在网页制作与设计中的应用研究

随着网络时代的来临,网页布局已经成为网页设计的关键点之一,DIV+CSS技术则成为众多网页布局方法中的主导技术,它在网页制作与设计中的地位也越来越高。文章对DIV+CSS技术进行了基本概述,并结合在教育资源网站平台的应用,介绍了DIV+CSS技术在网页格局上的设计。     

常用网页布局对比研究

在分析比较了表格布局和DIV+CSS布局的优缺点后,分别以表格布局和DIV+CSS布局为例布局了两个网页。并在布局的过程中比较两种布局的优缺点。通过比较发现使用DIV+CSS布局在布局灵活性和网页访问速度方面要优于表格布局。对于初学者和小型网站可以用表格布局;但对于大型网站和符合Web2.0技术规范网站推荐用DIV+CSS布局。     

网页制作中的DIV+CSS技术分析

随着计算机和互联网快的速发展,学会网页制作已经成为人们生活和工作中不可缺少的重要技能。对于建设网站来说,静态网页制作是其中的一个重要组成部分,制作网页已经成为一个基本的技能。文章分析了网页制作中的DIV+CSS技术。     

谈ASP.NET母版技术

利用ASP.NET开发网站时,可以使用主题和CSS解决多个页面批量布局的问题,用户控件也可解决多个网页局部内容共享的问题。但对于布局和内容等都相同或相似的多个页面批量开发最好使用母版技术。     

Dreamweaver CS3中用“spry菜单栏”制作网页导航菜单

网页导航菜单是一个网站的主线,是指引和方便浏览者访问所需内容的快速通道。本文介绍了Dreamweaver CS3中使用"Spry菜单栏"控件创建横向或纵向的网页下拉或弹出菜单,通过"属性"面板编辑"Spry菜单栏"控件,以及通过修改对应SpryMenuBarHorizontal.css或SpryMenuBarVertical.css文档中的CSS规则来更改菜单栏的外观。     

SmartDraw——让您成为专业绘图师

<正> 如今,Office97/2000在处理各种文稿方面已经用得非常普遍了,但是,在制作各种计算机及网络系统有线图、程序流程图、电子线路图等场合则显得力不从心,工程技术人员只能使用各种专业绘图软件。这些专业绘图软件制作的图片要插入到Office文档中往往需要各种转换,比较麻烦。下面介绍一个可供各类工程技术人员使用的绘图软件——SmartDraw,利用它可以在很短的时间内制作出可与专业绘图人员或使用专业绘图软件绘制的图表相媲美的图表。 读者可以到smartdraw.com网站免费下载SmartDraw绘图软件的试用版(http://www.smartdraw.com/smart-draw_jnstall2.exe),目前的最新版本为SmartDraw Ver5.0。使用     

Efficient Spectrum Sensing with Minimum Transmission Delay in Cognitive Radio Networks

In cognitive radio (CR) networks, the secondary users (SUs) need to find idle channels via spectrum sensing for their transmission. In this paper, we study the problem of designing the sensing time to minimize the SU transmission delay under the condition of sufficient protection to primary users (PUs). Energy detection sensing scheme is used to prove that the formulated problem indeed has one optimal sensing time which yields the minimum SU transmission delay. Then, we propose a novel cooperative spectrum sensing (CSS) framework, in which one SU’s reporting time can be used for other SUs’ sensing. The analysis focuses on two fusion strategies: soft information fusion and hard information fusion. Under soft information fusion, it is proved that there exists one optimal sensing time that minimizes the SU transmission delay. Under hard information fusion, for time varying channels, the novel multi-slot CSS is derived. The performance of SU transmission delay is studied in both perfect and imperfect reporting channels. Some simple algorithms are derived to calculate the optimal sensing settings that minimize the SU transmission delay. Computer simulations show that fundamental improvement of delay performance can be obtained by the optimal sensing settings. In addition, the novel multi-slot CSS scheme shows a much lower transmission delay than CSS based on general frame structure.     

CSS浏览器兼容性问题研究

针对层叠样式表浏览器兼容问题,文中分别从浏览器、兼容问题解决技巧和CSS调试3个方面入手。首先介绍常用浏览器;接着列出常见CSS浏览器兼容问题,并给出了解决方法;最后介绍两种界面设计者常用的检验工具:IETester和Firefug。     

三维控制图的应用

平均值x及极差R控制图是质量管理中用得最多的一种控制图,但它在日常生产中使用较困难,原因是经常有点跑出控制线外,即失控,而实际上生产线却无异常产生,这是从误报警而犯了第一类错误,这些主要是由平均值x及极差R控制图的局限性引起的。如果用平均值x及移动极差R控制图就完全可以解决以上问题,从而大大降低第一类风险而没有增加第二类风险。     

Towards centralized and semi‐automatic VLAN management

Virtual local area networks (VLANs) are widely used in many enterprises, campuses, and data‐centre networks. Although VLANs can restrict broadcast domains and contain hosts in one network or separate networks, the management of VLANs is an ad hoc and error‐prone work. In this paper, we design and implement a centralized and semi‐automatic system for VLAN management (CSS‐VM). Based on the physical network topology and user group (examples are engineering, student cluster, and faculty cluster) information, CSS‐VM can decide the number of VLANs that each user group would be partitioned into. In addition, CSS‐VM can not only monitor the status of devices and links but can also calculate an optimal spanning tree for each affected VLAN after a link or device failure is detected, so that it does not need to enable the Spanning Tree Protocol on devices but still has the ability of converging from device or link failures and avoiding bridging loops. We have evaluated CSS‐VM on the topology and VLAN partition data of an operational enterprise network. Our results show that CSS‐VM can obviously keep the broadcast traffic cost reasonable, efficiently partition and configure VLANs, quickly converge from link and device failures, and intelligently make a balanced use of links. Copyright © 2014 John Wiley & Sons, Ltd.     

A novel relay-aided centralized cooperative spectrum sensing scheme using radio frequency energy harvesting

In a cooperative spectrum sensing (CSS) network, the primary signal can be used as a radio frequency (RF) source in order to power the energy-constrained sensor nodes of the secondary network. This work presents a novel hybrid model combining an optimal relay selection scheme to incorporate RF energy harvesting in a centralized CSS network. The secondary users, which are equipped with RF energy harvesting capabilities, act as relays in order to forward the sensing information to a fusion center. Here, we have derived an enhanced multi-relay selection strategy to maximize the end-to-end signal-to-noise ratio of the links. Furthermore, a new voting rule is proposed based on the generalized K-out-of-M rule, such that it minimizes our objective error function. The performance analysis of our proposed model is presented with respect to the flexible relay positions. We have used complementary receiver operating characteristic curves for analyzing the detection performance of the CSS model with our derived voting rule. Simulation results using MATLAB show that the proposed model gives a better detection probability and a smaller error rate than some related existing works.     

Protecting the method of auxiliary sources (MAS) solutions from the interior resonance problem

The method of auxiliary sources (MAS) has been used for the numerical solution of a variety of electromagnetic problems successfully. Since MAS can be considered as a modified or generalized version of the standard surface integral equation technique (SIE), it has the interior resonance problem, but the remedies to this problem have not been investigated yet. In this letter, it is shown that the interior resonance problem in applying MAS can be completely removed using combined-source solution (CSS).     

DIV＋CSS技术在诚欣电子商城系统中的应用研究

以DIV＋CSS技术在诚欣电子商城系统中的应用为切入点对DIV＋CSS技术进行深入的探讨。首先对DIV＋CSS网页重构技术进行了讨论：然后对DIV和CSS技术在诚欣电子商城系统的页面设计中的应用进行了分析与讨论，同时给出了具体的实现代码；最后在DIV＋CSS技术在诚欣电子商城系统中的应用的基础上对DIV＋CSS技术进行了解析．并总结出了DIV＋CSS布局网站的优点和缺陷。     

Mitigating spectrum sensing data falsification attack in ad hoc cognitive radio networks

In a cognitive radio ad hoc network, there is no central authority. Hence, distributed collaborative spectrum sensing (CSS) plays a major role in achieving an accurate spectrum sensing result. However, CSS is sensitive to spectrum sensing data falsification (SSDF) attack, in which a malicious user falsifies its local sensing report before disseminating it into the network. To capture such abnormal behavior of a node, we present an approach for detecting SSDF attack based on dissimilarity score. A secondary user (SU) computes the dissimilarity score of its neighbors from the messages received from its h‐hop neighbors. Further, we also present how the proposed scheme can be used on the sequence of sensing reports to detect and isolate the malicious SUs on the fly.     

网页制作中层的技术及其应用

网页制作的布局一直是很多人非常关心的一个问题,早期的设计者大多使用表格定位的方法对页面元素进行定位,尽管如此,表格定位也只能解决平面布局中的定位问题。随着对人们对平面布局精确度要求的提高和三维空间定位的需求增加,越来越复杂的表格及浏览器解释时间的增加成了许多设计者难以忍受的问题。为了解除这些困扰,W3C在新的CSS中包含了一个绝对定位的特性,他允许设计者将页面上的的某个元素定位到任何地方,除了平面上定位,还增加了三维空间的定位Z-INDEX。因为Z-INDEX定义了堆叠的顺序,类似于图形设计中使用的图层,所以拥有了Z-INDEX属性的块元素被形象地称为层。主要论述层的基本知识,介绍了层的用法,并在最后给出用层来解决一个考试系统的浮动层的实现方法。     

抽油机悬点载荷计算图版的数学模拟

美国石油学会公式是计算抽油机悬点载荷常用的公式之一,在该公式中,有两个无因次参数需要人工读图才能够查出。利用图像识别技术读取图版曲线上的数据点,对曲线进行数学模拟,使其能方便地应用于工程计算之中。