基于4G通信的网络结构与关键技术分析

近年来,伴随着计算机、电子技术和互联网信息技术的飞速发展,3G网络已在世界范围内得到了普及,但是3G通信网络的应用存在一些亟待解决的问题,无法满足人们对通信网络的需求。与此同时,4G网络作为一种新型的通信形式,具有速度快、网络频谱宽、智能性和通信质量高以及通信费用便宜等优势,受到了越来越多人的青睐,并逐渐被推广。本文将从当前4G通信网络的发展实际出发,概述4G通信网络技术,进而分析4G通信网络的结构,最后阐述4G通信网络的关键技术,希望能让更多人加大对4G通信网络的了解和认识。     

5G通信场景下分布式基站的部署策略

我国5G通信网络技术已处于领先位置,部分城市开始试点建设5G基站。相比4G网络,5G网络在接入能力、数据传输方面均有更高的表现,但5G基站建设需要达到更高的密度。目前,光缆网基础资源与5G网络建设需求存在一定差距,必须大幅度升级、整合光缆网,才能满足5G网络的建设需求。分布式基站(BBU+RRU)将逐步成为移动网络基站的主流形态。     

4G网络通信新技术研究

4G网络通信是指它除了提供传统2G、3G通信的语音业务之外,还能够提供基于视频、数据、语音的各种服务,给客户带来高速的视频通信和数据通信,实现真正的沟通自由,彻底改变我们的社会形态和生活方式。本文首先阐述了4G网络通信新技术的特点,其次,就4G网络通信新技术的应用进行了深入的探讨,提出了自己的建议和看法,具有一定的参考价值。     

试论4G通信的无线网络安全通信分析

当前世界都步入到了信息化的时代,我们也正处于第三次信息革命的当下,无线通信网络也有了飞快的发展,从最初的1G网络发展到如今的4G网络,相信在不久的将来还会有5G、6G.4G的实现使得通信速度与传递信效率上有了明显的提升,现在没有4G网络的就难以享受快速的上网速度.在4G通信的快速发展过程中,最关键的内容就是网络安全问题.对此,本文将主要对4G通信的无线网络安全通信进行分析,找出其存在的问题以及提出相应的解决对策.     

浅谈分布式虚拟现实及其实时性研究

分布式虚拟现实系统简称DVR,是虚拟现实系统的一种类型,它是基于网络的虚拟环境。在这个环境中,位于不同物理环境位置的多个用户或多个虚拟环境通过网络相连接,或者多个用户同时参加一个虚拟现实环境,通过计算机与其他用户进行交互,并共享信息。在分布式虚拟现实系统中,多个q用户可通过网络对同一虚拟世界进行观察和操作,以达到协同工作的目的。简单地说是指一个支持多人实时通过网络进行交互的软件系统,每个用户在一个虚拟现实环境中,通过计算机与其它用户进行交互,并共享信息。     

基于分布式的坦克仿真系统的框架设计

文章在分析两个经典的分布式虚拟现实系统的基础上,结合坦克仿真的具体情况,从通用性和开放性角度考虑,提出了分布式坦克仿真（DTS）系统的软件体系结构。然后从人机交互、网络通信、实体管理、多视觉通道图形显示等方面详细介绍了DTS系统的设计情况。     

4G通信安全技术的创新与发展

随着现代化科技的应用及普及,通信技术也有了质的飞跃。4G通信技术的产生及应用为现代化事业的发展起了推波助澜的作用。随着4G通信的普及,人们不断地享受着更加快捷、简便的网络体验。相对的安全问题也就随之暴露出来。本文先就4G通信技术进行了简单的阐述,而后就4G网络面临的安全问题以及4G通信安全技术存在的问题进行了深入的分析与探讨,并提出了建立4G通信系统的安全机制、改变密码体制等4G通信安全技术的创新与发展的措施。     

浅谈分布式虚拟现实及其实时性研究

分布式虚拟现实系统简称DVR,是虚拟现实系统的一种类型,它是基于网络的虚拟环境。在这个环境中,位于不同物理环境位置的多个用户或多个虚拟环境通过网络相连接,或者多个用户同时参加一个虚拟现实环境,通过计算机与其他用户进行交互,并共享信息。在分布式虚拟现实系统中,多个q用户可通过网络对同一虚拟世界进行观察和操作,以达到协同工作的目的。简单地说是指一个支持多人实时通过网络进行交互的软件系统,每个用户在一个虚拟现实环境中,通过计算机与其它用户进行交互,并共享信息。     

光传输通信技术下的4G通信发展研究

信息化时代的到来,使得人们的生活、工作、娱乐等都离不开网络,4G通信技术具有网速快,覆盖面积大的特点,能够满足人们的网络需求,有助于社会的发展.本文针对光传输通信技术下的4G通信发展进行研究,论述了4G移动通信技术的特征,光传输通信技术的种类概述,以及光传输通信技术下的4G通信发展.     

浅析光通信技术在4G发展中的应用

2010年12月,Verizon公司部署了4G LTE网络,并承诺提供高于其3G网络10倍的性能。此外,随着iPhone等热门移动设备的推出,网络带宽也呈现出成倍的巨幅增长。本文在对光通信技术及4G通信技术进行概述的基础上,对光通信技术在4G发展中的应用进行了分析。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.