流媒体中一种高质量视频内容的设计

结合当前流行的流媒体技术,深入分析了流媒体技术及其文件格式,讨论了如何实现流媒体高质量的视频内容.在此基础上,本文实现了一个基于流媒体的高质量视频内容的设计.     

数字图书馆技术引导数字图书馆文献信息发展的趋势

数字时代,数字图书馆技术为数字图书馆文献信息服务提供了新的手段,方式方法,途径,使之在服务深度上发生了深刻的变化,为数字图书馆文献信息服务提供了新的发展趋势.     

CAN总线位速率参数在实际应用中设置的研究分析

CAN总线是一种有效支持分布式控制和实时控制的、多主的异步串行通信网络。CAN通信中的波特率、位周期内取样点数和位置的设置极大地影响了CAN性能的发挥。优化位定时参数,能够保证信息同步,并且对它设置的恰当与否关系着整个系统通信的成败。本文就是针对这点来说明位定时参数的确定方法及其重要性。     

现代汉语的“一点儿”和“有点儿”——从对外汉语教学说起

从对外汉语教学的实践出发,我们发现了留学生容易对“一点儿”和“有点儿”的用法混淆,因此有必要对现代汉语中“一点儿”和“有点儿”的混淆成因进行理论上的分析并进一步指出二者在用法和语义上细微的差异。     

基于CDMA多用户检测的方法

本文主要给出了CDMA系统和CDMA多用户检测的一般模型，并列出了目前CDMA多用户检测的几种解决方案及其性能的比较，提出了CDMA多用户检测还有许多需要完善的方面。     

浅论数字图书馆及其建设中面临的问题

本文介绍了数字图书馆的概念，分析了数字图书馆的特征，论述了国内外数字图书馆的发展状况和数字图书馆建设中存在的不可忽视的问题及相关对策。     

PDC钻头喷嘴倾角流场特性模拟研究

利用数值模拟的手段,在K-ε方程数学模型上计算封闭的N-S方程,对不同类型的PDC钻头喷嘴倾角组合进行了流场模拟。模拟结果表明:喷嘴倾角对PDC钻头的井底流场有明显的影响,不同的喷嘴倾角组合,井底流场特性不同,水力清岩的效果不同。保持中心喷嘴倾角一定,外围喷嘴倾角为20°~30°时,能使井底压力场、速度场达到最优。保持外围喷嘴倾角一定,中心喷嘴倾角为12°~22°时,能使井底压力场、速度场达到最优。     

A new method for performance evaluation of bit decoding algorithms using statistics of the log likelihood ratio

This paper presents a new method for the performance evaluation of bit decoding algorithms. The method is based on estimating the probability density function (pdf) of the bit log likelihood ratio (LLR) by using an exponential model. It is widely known that the pdf of the bit LLR is close to the normal density. The proposed approach takes advantage of this property to present an efficient algorithm for the pdf estimation. The moment matching method is combined with the maximum entropy principle to estimate the underlying parameters. We present a simple method for computing the probabilities of the point estimates for the estimated parameters, as well as for the bit error rate. The corresponding results are used to compute the number of samples that are required for a given precision of the estimated values. It is demonstrated that this method requires significantly fewer samples as compared to the conventional Monte-Carlo simulation.     

基于BT的校园信息网络

BT技术在文件传输方面迅速普及,在校园网络环境中有很强的应用前景。将BT技术的原理和校园网络实际情况有机结合,通过实际建立BT服务器、发布BT资源、下载等一系列工作,更好地利用现有的网络环境资源,可建立适合校园网络的新型资源共享应用平台。     

Video coding optimization in AVS2

Chinese second generation of the Audio Video Coding Standard, known as the AVS2, competing with HEVC/H.265 and AV1, has become a well-known video compression standard. Many unique tools have been developed and incorporated in AVS2. This paper proposes several encoder optimization schemes with respect to rate-distortion optimization (RDO). Specifically, by exploiting the close relationship between the total number of referenced pictures and the hierarchy of reference structure, a reference structure determined parameter (RSDP) algorithm reallocates Lagrange multiplier. Moreover, an adaptive quantization parameter offset (AQPO) algorithm is provided at both picture-level and Groups of Pictures (GoP)-level to adjust quantization parameters adaptively on top of the preassigned ones. Both RSDP algorithm and AQPO algorithm have already been adopted by AVS2 and incorporated in its reference software. Experimental results show that in the low-delay, RSDP and AQPO achieved savings of 1.35% and 1.26% on BDBR, respectively.