5G中的编码调制与多址技术

本节讲座介绍了5G通信中的载波调制和编码技术,包括二相相移键控、四相相移键控、正交振幅调制,低密度奇偶校验码和极化码等,多址技术包括正交多址和非正交多址,说明其基本原理和特点及应用场合。     

Job schedulers for Big data processing in Hadoop environment: testing real-life schedulers using benchmark programs

At present, big data is very popular, because it has proved to be much successful in many fields such as social media, E-commerce transactions, etc. Big data describes the tools and technologies needed to capture, manage, store, distribute, and analyze petabyte or larger-sized datasets having different structures with high speed. Big data can be structured, unstructured, or semi structured. Hadoop is an open source framework that is used to process large amounts of data in an inexpensive and efficient way, and job scheduling is a key factor for achieving high performance in big data processing. This paper gives an overview of big data and highlights the problems and challenges in big data. It then highlights Hadoop Distributed File System (HDFS), Hadoop MapReduce, and various parameters that affect the performance of job scheduling algorithms in big data such as Job Tracker, Task Tracker, Name Node, Data Node, etc. The primary purpose of this paper is to present a comparative study of job scheduling algorithms along with their experimental results in Hadoop environment. In addition, this paper describes the advantages, disadvantages, features, and drawbacks of various Hadoop job schedulers such as FIFO, Fair, capacity, Deadline Constraints, Delay, LATE, Resource Aware, etc, and provides a comparative study among these schedulers.     

运动估计算法分析

对常用的运动补偿图像算法（如全搜索法、三步法、共轭方向搜索法、两维对数下降法等）从各个方面进行了比较,最终选出最快、最准确的算法-两步搜索法。     

A dynamic model for the assessment of the replacement of lead in solders

A dynamic, interactive map has been developed of the life cycle of a number of metals, from mining through to minerals processing, metal production, product manufacturing, recovery, and waste management. While the existing metal process network and waste management infrastructure provide substantial scope for (product) design, these also limit change because of the strong path dependency of industry and infrastructure development. Therefore, models for dynamic simulation were constructed that allow the specification and evaluation of the metal process network and waste management infrastructure “products” over a longer time span. The model has been constructed using a bottom-up approach, to enable assessment of the environmental aspects of metallurgy, and to simulate changes in the system structure and technology, i.e., from the reactor or individual process step up to integrated material cycles. This dynamic interconnected model is used to investigate the impact of the removal of lead from solders on the coupled flows of the metals Ag, Au, Bi, Cu, Fe, Ni, Pb, Sn, Zn, and PGMs.     

国际音频技术研究进展

通过对第117届、118届、119届、120届AES大会的统计分析,介绍了国际上关于扬声器、传声器、信号处理、音频编码、空间感及处理、仪器与测量、扩声、高清音频、多通道声、心理声学感知与听音试验、汽车音响等方面音频技术研究的最新进展。     

智能语音操控在广电端到端的系统设计及应用

在数字化中国的大背景下,在公司个人宽带与互动电视在线交费用户均突破300万户的情况下,为解决我们的用户总找不到自己喜欢看的节目,记不住频道名称和喜欢的节目,提升公司竞争力。通过对前端的点播系统、AAA系统、EPG系统、PORTAL系统、ISMP系统、媒资系统、机顶盒终端的功能进行剥离、整合和详细设计,最后完成终端用户语音操控电视直播、点播、时移、回看、页面操控、系统设置,并支持普通话和四川话方言的目的。达到提升用户体验,增加公司竞争力,促进业务的发展。系统试运行后,用户体验效果得到很大提升,完全达到预期设计目的。     

谈对电子元器件企业设计开发过程中“六性”的审核

通过对电子元器件企业＂可靠性、维修性、保障性、测试性、安全性和环境适应性＂的审核,帮助企业识别＂可靠性、维修性、保障性、测试性、安全性和环境适应性＂,认识＂可靠性、维修性、保障性、测试性、安全性和环境适应性＂在产品设计开发中的重要性,实现产品的＂可靠性、维修性、保障性、测试性、安全性和环境适应性＂指标。     

Hydrogel Adhesion: A Supramolecular Synergy of Chemistry,Topology, and Mechanics

Adhering hydrogels to various materials is fundamental to a large array of established and emerging applications. The last few years have seen transformative advances in achieving strong hydrogel adhesion, which is a supramolecular phenomenon. Two adherends connect through covalent bonds, noncovalent complexes, polymer chains, polymer networks, or nanoparticles. Separating the adherends dissipates energy through cascading events across length scales, including bond cleavage, chain retraction, and bulk hysteresis. A unifying principle has emerged: strong hydrogel adhesion requires the synergy of chemistry of bonds, topology of connection, and mechanics of dissipation. This synergy characterizes hydrogel adhesion to various materials (another hydrogel, tissue, elastomer, plastic, metal, glass, and ceramic) in various operations (cast, coat, print, attach, pierce, and glue). Strong adhesion can be made permanent, reversible, degradable, or on‐demand detachable. The development of hydrogel adhesion and its applications adheres disciplines, discovers interlinks, and forges cohesion. Discussed throughout the review are immediate opportunities for fundamental studies and practical applications.     

基于专用集成电路的雷达动目标检测信号处理器

雷达动目标检测的实时信号处理原来一般用模拟器件和通用数字信号处理器（ＤＳＰ）实现。本文设计了基于数字专用集成电路的雷达目标检测实时信号处理系统，本文对该信号处理系统的雷达背景视频产生，单元平均恒虚警率（ＣＦＡＲ）检测，杂波图形成，动目标提取，视频信号积累，雷达定时器和控制等用现场可编程门阵列（ＦＰＧＡ）进行了专用集成电路设计，该系统性能稳定，抗干扰能力强，体积小，便于调试，已投入实用。     

One dimensional-ZnO nanostructures: Synthesis,properties and environmental applications

One-dimensional (1D) zinc oxide (ZnO) nanostructures such as rods, wires, belts and tubes have attracted much attention due to their unique physical, chemical, optical, and electrochemical properties enabling remarkable performance in photonics, sensors, photocatalysis, optics and photovoltaic devices. This paper presents a review of recent research in 1D ZnO nanostructures with emphasis on ZnO-based nanowires (NWs or NRs) used as photocatalysts for the degradation of environmental pollutants, particularly textile and industrial dyes, under appropriate light irradiation. Compared to other ZnO nanostructures, the higher aspect ratio (large surface to volume ratio) of 1D ZnO NWs offers highly desirable photocatalytic applications that depend on surface reactions or other phenomena that occur at interface surfaces, and eliminate the cost and requirement for post treatment. In addition, a review of several syntheses, fabrication methods and characterization studies of several types of ZnO NWs is presented. Finally, the photocatalytic degradation of selected dyes is highlighted.