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Low-Complexity Joint Channel Estimation and Symbol Detection for OFDMA Systems 预览
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作者 Rui Xin Zuyao Ni +2 位作者 Sheng Wu Linling Kuang Chunxiao Jiang 《中国通信:英文版》 SCIE CSCD 2019年第7期49-60,共12页
In this paper, we propose a joint channel estimation and symbol detection (JCESD) algorithm relying on message-passing algorithms (MPA) for orthogonal frequency division multiple access (OFDMA) systems. The channel es... In this paper, we propose a joint channel estimation and symbol detection (JCESD) algorithm relying on message-passing algorithms (MPA) for orthogonal frequency division multiple access (OFDMA) systems. The channel estimation and symbol detection leverage the framework of expectation propagation (EP) and belief propagation (BP) with the aid of Gaussian approximation, respectively. Furthermore, to reduce the computation complexity involved in channel estimation, the matrix inversion is transformed into a series of diagonal matrix inversions through the Sherman-Morrison formula. Simulation experiments show that the proposed algorithm can reduce the pilot overhead by about 50%, compared with the traditional linear minimum mean square error (LMMSE) algorithm, and can approach to the bit error rate (BER) performance bound of perfectly known channel state information within 0.1 dB. 展开更多
关键词 JOINT channel estimation and SYMBOL detection MESSAGE PASSING OFDMA
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Fast Confidentiality-Preserving Authentication for Vehicular Ad Hoc Networks
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作者 MIRZAEE Siavash 蒋乐天 《上海交通大学学报:英文版》 EI 2019年第1期31-40,共10页
This paper studies the existing problems of message authentication protocols in vehicular ad hoc networks(VANETs) due to their significance in the future of commuting and transportation. Our contribution has been devo... This paper studies the existing problems of message authentication protocols in vehicular ad hoc networks(VANETs) due to their significance in the future of commuting and transportation. Our contribution has been devoted to implementing a new protocol for VANETs so that inherent security problems in past works are resolved. Exclusive security measures have been considered for the system which protects the users against threat of any attack. The new protocol shows a great hardness guaranteed by certificate based 80 bit security which assures messages to remain confidential in any time. Also, new unprecedented features like V2 X which improves system performance effectively have been instantiated. The simulation results indicate that message signature generation and verification both take place in much less time than present comparable rival protocols. 展开更多
关键词 message AUTHENTICATION protocol vehicular ad HOC networks(VANETs) SIGNATURE generation and verification
基于FPGA的高速冗余I/O总线设计与实现 预览
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作者 刘鎏 臧峰 牛洪海 《自动化仪表》 CAS 2019年第4期69-72,共4页
为了实现控制器与I/O模块之间的数据实时、可靠传输,设计并实现了一种基于现场可编程门阵列(FPGA)的控制系统高速冗余输入/输出(I/O)总线。其物理层采用多点低压差分信号标准。因此,该总线具有高实时性、高吞吐率和易扩展等特点。控制... 为了实现控制器与I/O模块之间的数据实时、可靠传输,设计并实现了一种基于现场可编程门阵列(FPGA)的控制系统高速冗余输入/输出(I/O)总线。其物理层采用多点低压差分信号标准。因此,该总线具有高实时性、高吞吐率和易扩展等特点。控制器通过A/B总线交替实现与I/O模块的通信,实时监测链路状态并采集I/O模块数据。利用非实时时隙,可以实现I/O模块对时、内存监视等非实时报文的控制。控制器ARM芯片运行QNX实时操作系统,通过直接内存存取(DMA)把需要与I/O通信的报文传输给FPGA。FPGA接收到报文后进行解析,并在报文末尾自动填入循环冗余校验(CRC)码和帧尾标志。FPGA接收到I/O模块反馈的数据后进行循环冗余校验:校验通过则填入对应模块接收缓冲区;校验错误则在相应I/O模块的寄存器填入循环冗余校验错误标志,以减轻ARM芯片的负载。该基于FPGA的高速冗余I/O通信总线,在实际应用中取得了很好的使用效果。 展开更多
关键词 现场可编程门阵列 冗余 I/O总线 实时性 报文 QNX 直接内存存取
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Improvement Design for Distributed Real-Time Stream Processing Systems 预览
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作者 Wei Jiang Liu-Gen Xu +1 位作者 Hai-Bo Hu Yue Ma 《电子科技学刊:英文版》 CAS CSCD 2019年第1期3-12,共10页
In the era of Big Data,typical architecture of distributed real-time stream processing systems is the combination of Flume,Kafka,and Storm.As a kind of distributed message system,Kafka has the characteristics of horiz... In the era of Big Data,typical architecture of distributed real-time stream processing systems is the combination of Flume,Kafka,and Storm.As a kind of distributed message system,Kafka has the characteristics of horizontal scalability and high throughput,which is manly deployed in many areas in order to address the problem of speed mismatch between message producers and consumers.When using Kafka,we need to quickly receive data sent by producers.In addition,we need to send data to consumers quickly.Therefore,the performance of Kafka is of critical importance to the performance of the whole stream processing system.In this paper,we propose the improved design of real-time stream processing systems,and focus on improving the Kafka's data loading process.We use Kafka cat to transfer data from the source to Kafka topic directly,which can reduce the network transmission.We also utilize the memory file system to accelerate the process of data loading,which can address the bottleneck and performance problems caused by disk I/O.Extensive experiments are conducted to evaluate the performance,which show the superiority of our improved design. 展开更多
关键词 Kafka Kafka cat memory file SYSTEM MESSAGE QUEUE real-time STREAM processing SYSTEM
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初心不改铸精品学术期刊
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作者 任红 《中华肝脏病杂志》 CAS CSCD 北大核心 2019年第1期1-2,共2页
《中华肝脏病杂志》2018年刊出论文222篇,各级基金资助论文占50.5%。核心影响因子继续位居消化病学类期刊第一位,继续荣获"百种中国杰出学术期刊"称号,并获得2018年中国科学技术协会中文科技期刊精品建设计划项目资助。组织... 《中华肝脏病杂志》2018年刊出论文222篇,各级基金资助论文占50.5%。核心影响因子继续位居消化病学类期刊第一位,继续荣获"百种中国杰出学术期刊"称号,并获得2018年中国科学技术协会中文科技期刊精品建设计划项目资助。组织协办的"全国肝脏疾病临床学术大会暨国际肝病学会日"及"慢性病毒性肝炎抗病毒治疗难点和热点学术会议"分别于2018年5月和11月召开。2019年将继续办好杂志、办好会议。恪守"求真创新,追求卓越"的办刊理念,初心不改,倾力打造精品学术期刊。 展开更多
关键词 寄语 回顾 计划
CAN总线控制器CRC校验码的设计原理及实现 预览
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作者 王爽 《微处理机》 2019年第3期25-28,共4页
随着集成电路产业快速发展,电子系统的设计日趋复杂,为了在电子系统设计中实现标准化的设计及设备间的管理,采用现场可编程总线接口,规范设备间的互连设计,提高系统性能。对CAN总线控制器中循环冗余校验码的差错控制原理及其设计实现方... 随着集成电路产业快速发展,电子系统的设计日趋复杂,为了在电子系统设计中实现标准化的设计及设备间的管理,采用现场可编程总线接口,规范设备间的互连设计,提高系统性能。对CAN总线控制器中循环冗余校验码的差错控制原理及其设计实现方法进行了介绍。对传输报文过程中的传输校验等差错控制进行设计,显著降低CAN网络的报文传输误码率,确保报文及时、可靠地送达接收方并有效地检测与防范传输错误。通过仿真实验表明,发送方与接收方的CRC计算结果相同,成功实现了接收方对数据的接收与校验。 展开更多
关键词 CAN总线 循环冗余校验 差错控制 报文
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CENTUM VP流程图的一键拷贝 预览
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作者 尹文永 《化工自动化及仪表》 CAS 2019年第4期324-325,共2页
概述了横河CENTUM VP DCS系统在化工生产中实现自动拷贝流程画面的方法,该方法主要利用VP自带的Hard Copy和Sequence Message Request功能,通过编写相应程序来实现自动拷贝。
关键词 CENTUM VP 流程图拷贝 Hard COPY Sequence Message REQUEST
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A RELIC'S RETURN
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作者 孙佳慧 《汉语世界:英文版》 2019年第3期12-14,共3页
"Welcome home, Tiger Ying!" When hundreds of netizens posted this welcome message in November 2018, it was not to hail the arrival of some beloved athlete or celebrity Instead, they were celebrating the retu... "Welcome home, Tiger Ying!" When hundreds of netizens posted this welcome message in November 2018, it was not to hail the arrival of some beloved athlete or celebrity Instead, they were celebrating the return of a 3,000-year-old vessel, looted in 1860 and kept abroad for over 100 years. 展开更多
关键词 MESSAGE YEARS ARRIVAL
Li’s Upbeat Message Is Seen as Sign of New Confidence 预览
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作者 ANDREW MOODY 《今日中国:英文版》 2019年第4期10-11,共2页
PREMIER Li Keqiang recently stated that the Chinese economy continues to provide vital support to the global economy despite concerns of a slowdown.
关键词 Li Keqiang Upbeat MESSAGE global ECONOMY despite CONCERNS
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Communication Channel Between Teachers and Students in Chemistry Education: WhatsApp 预览
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作者 Nuray ZAN 《美中教育评论:A》 2019年第1期18-30,共13页
WhatsApp is a smartphone application used for instant messaging. It has been popular in the community in recent years, but it also has been used in education. In the field of education, there are studies related to fi... WhatsApp is a smartphone application used for instant messaging. It has been popular in the community in recent years, but it also has been used in education. In the field of education, there are studies related to field-specific subjects in English and chemistry education related to the use of WhatsApp during school hours and outside of school time. However, there could not be reached any study investigating how a specific field teacher and students use this application in voluntary groups without being bound to a particular program. For this purpose, semi-structured interviews were conducted with chemistry teachers by using WhatsApp application to communicate with students. A study was conducted with eight volunteer chemistry teachers working in State Anatolian High Schools in ?ankiri and Ankara provinces. In this study conducted with the teachers at high school level, it was found out that WhatsApp application is used for five main purposes: First, these are increasing the students’ motivation for the course, strengthening the communication, encouraging information sharing among students, using as an opportunity to learn, and planning the study process. The messages that accelerate the tempo of study to increase the motivation of the students about the course, sending clues about the content of the course, expressions that make them feel the success, messages indicating that their identity and personalities are valuable, the photographs of the moments experienced together were evaluated within the first scope. Second were the messages, to strengthen communication, celebrating special days and achievements, and increasing the sense of belonging. Third, information sharing content was composed of audio record, problem, solution of the problem, visuals, and documents related to a subject. Fourth, instant answers given about an unclear topic, related questions and answers were discussed in the opportunity to learn category. Finally, reminding the deadline for projects and assignments, time for exam preparation. 展开更多
关键词 CHEMISTRY EDUCATION WhatsApp SOCIAL network INSTANT MESSAGE COMMUNICATION
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Getting the Message Across China-Egypt media cooperation seeks to disseminate accurate news, counter misinformation
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作者 Hazem Samir 《中国与非洲:英文版》 2019年第6期36-37,共2页
As the media is one of the essential tools to cement bonds between peoples, Egypt's State Information Service (SIS) signed cooperation protocols with a number of Chinese media institutions to promote ties between ... As the media is one of the essential tools to cement bonds between peoples, Egypt's State Information Service (SIS) signed cooperation protocols with a number of Chinese media institutions to promote ties between the two countries in this area in 2016. These protocols now include an SIS online portal in Chinese language launched in April this year that will feature information and news to keep the public informed about important issues in Africa and China, as well as the cooperation among them. SIS is Egypt's official media and public relations organ responsible for regulating the affairs of foreign press and media correspondents in Egypt. 展开更多
关键词 Message ACROSS China-Egypt MEDIA
Cooperative transmission in delay tolerant network 预览
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作者 WANG Rong WU Yahui +1 位作者 HUANG Hongbin DENG Su 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第1期30-36,共7页
The delay tolerant network (DTN) is an emerging concept, which is used to describe the network, where the communication link may disrupt frequently. To cope with this problem, the DTN uses the store-carry-forward (SCF... The delay tolerant network (DTN) is an emerging concept, which is used to describe the network, where the communication link may disrupt frequently. To cope with this problem, the DTN uses the store-carry-forward (SCF) transmission mode. With this policy, the messages in the DTN are transmitted based on the nodes' cooperation. However, the nodes may be selfish, so the source has to pay certain rewards for others to get their help. This paper studies the optimal incentive policy to maximize the source's final utility. First, it models the message spreading process as several ordinary differential equations (ODEs) based on the meanfield approximation. Then, it mathematically gets the optimal policy and explores the structure of the policy. Finally, it checks the accuracy of the ODEs model and shows the advantages of the optimal policy through simulation and theoretical results respectively. 展开更多
关键词 DELAY TOLERANT network (DTN) OPTIMAL control MESSAGE transmission.
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分布式电池管理系统CAN总线通信仿真试验研究
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作者 张晓宇 孙俏 《电子测量技术》 2019年第9期55-58,共4页
电池管理系统在新能源纯电动汽车中扮演着非常重要的角色,分布式动力电池管理系统是一种多模块控制的集成系统,各个控制模块之间CAN总线通信存在复杂性和迟滞性,针对这一问题,采用CANoe/MATLAB联合仿真的方法对其进行试验。其中,在MATLA... 电池管理系统在新能源纯电动汽车中扮演着非常重要的角色,分布式动力电池管理系统是一种多模块控制的集成系统,各个控制模块之间CAN总线通信存在复杂性和迟滞性,针对这一问题,采用CANoe/MATLAB联合仿真的方法对其进行试验。其中,在MATLAB/Simulink仿真建模环境下建立了信号采集、SOC估算和故障诊断的多模块通信模型,同时在CANoe总线仿真平台建立了分布式电池管理系统的CAN网络架构,验证了多模块之间通信的实时性和准确性。结果表明,CANoe/MATLAB联合仿真的方法对分布式电池管理系统的通信策略开发提供了便捷。 展开更多
关键词 分布式电池管理系统 故障诊断 CAN总线 报文
一种工程项目中的网络实现 预览
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作者 程西娜 蔡文斋 《太赫兹科学与电子信息学报》 北大核心 2019年第1期141-145,共5页
介绍了一种工程项目中整个网络系统的编程实现方法。采用Indy10组件实现了网络通信;使用用户消息机制完成了协议级置码、解码;使用初始化(INI)文件技术实现了网络参数配置的编辑与装载;使用内存对齐技术实现了协议的快速内存交换;开发... 介绍了一种工程项目中整个网络系统的编程实现方法。采用Indy10组件实现了网络通信;使用用户消息机制完成了协议级置码、解码;使用初始化(INI)文件技术实现了网络参数配置的编辑与装载;使用内存对齐技术实现了协议的快速内存交换;开发出工程使用的统一网络配置、网络调试、网络通信与管理函数;设计了整个工程中网络模块与业务逻辑模块的通信机制与数据交换方法,制作并开发出整套工程用的监控系统。目前整套工程样机已参加了大系统联试,并通过总体单位验收。 展开更多
关键词 传感器 消息 网络通信 初始化文件
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浅析《推拿》小说和电影的异同 预览
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作者 沙茜 《山西青年职业学院学报》 2019年第1期86-88,共3页
《推拿》小说和电影以盲人这个特殊群体为题材,展现了盲人不同于健全人的生命轨迹和情感经历,突出了盲人的自尊与自爱,摒弃了传统观念对盲人的怜悯与同情,从盲人的角度感受和理解世界。小说和电影以不同的艺术方式表达了对盲人生命个体... 《推拿》小说和电影以盲人这个特殊群体为题材,展现了盲人不同于健全人的生命轨迹和情感经历,突出了盲人的自尊与自爱,摒弃了传统观念对盲人的怜悯与同情,从盲人的角度感受和理解世界。小说和电影以不同的艺术方式表达了对盲人生命个体的尊重,并通过盲人和健全人的对比,突出了盲人人格中的高贵。此外,作为不同的文本媒介,小说力图以全景式的结构对盲人进行群像描写;电影则突显了导演的美学风格,以散点透视的方式刻画主要人物,填补了小说的空白。 展开更多
关键词 《推拿》 小说 电影 异同
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以“通利血脉”治疗脑卒中后认知障碍 预览
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作者 陈艳懂 苏同生 《世界最新医学信息文摘(电子版)》 2019年第35期218-219,共2页
我国脑卒中发病率逐年呈增长趋势发展,脑卒中引起认知功能障碍病群多集中于65岁以上。通过对中医基础理论及西医发病机制分析,脑部血液循环是否流畅,对认知功能起着决定性作用,尤其额叶、颞叶、深部白质区等关键部位的损伤,直接侵害认... 我国脑卒中发病率逐年呈增长趋势发展,脑卒中引起认知功能障碍病群多集中于65岁以上。通过对中医基础理论及西医发病机制分析,脑部血液循环是否流畅,对认知功能起着决定性作用,尤其额叶、颞叶、深部白质区等关键部位的损伤,直接侵害认知功能。在治疗上,通过运用针灸、推拿改善局部血液循环,改善脑部缺血、缺氧状态,以达到治疗认知功能障碍。 展开更多
关键词 脑卒中 认知功能障碍 血脉 针灸 推拿
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云计算背景下VXLAN技术的应用 预览
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作者 张少芳 刘延锋 《无线互联科技》 2019年第9期136-138,共3页
在云计算的背景下,服务器的虚拟化对传统网络的数据迁移能力提出了非常高的要求。文章分析了当前非常典型的一种网络虚拟化技术—VXLAN技术,通过在三层IP网络之上建立基于数据链路层的逻辑隧道,使数据链路层数据能够穿越网络层的承载网... 在云计算的背景下,服务器的虚拟化对传统网络的数据迁移能力提出了非常高的要求。文章分析了当前非常典型的一种网络虚拟化技术—VXLAN技术,通过在三层IP网络之上建立基于数据链路层的逻辑隧道,使数据链路层数据能够穿越网络层的承载网络进行传递,实现虚拟机跨三层网络的动态迁移,有效地提高了数据的传输效率以及对硬件资源的利用率。 展开更多
关键词 云计算 虚拟机 SDN VXLAN 报文
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面向企业的一种ESB应用集成研究 预览
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作者 李志英 赵文龙 张麦龙 《信息与电脑》 2019年第3期123-125,共3页
随着信息化技术的不断发展,企业会逐步引进越来越多的应用系统。笔者首先初步探讨了ESB概念、基本功能以及相关技术等。其次,详细介绍了面向企业应用的ESB集成,分别从基于管理和技术两个角度的平台体系架构、业务集成原理以及硬件集群... 随着信息化技术的不断发展,企业会逐步引进越来越多的应用系统。笔者首先初步探讨了ESB概念、基本功能以及相关技术等。其次,详细介绍了面向企业应用的ESB集成,分别从基于管理和技术两个角度的平台体系架构、业务集成原理以及硬件集群部署等方面进行阐述。最后,简要描述了成功构建的ESB平台对企业各个IT系统和整个信息技术的影响,对企业未来发展规划的重要意义。 展开更多
关键词 企业服务总线 消息 服务规范 集群
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Message from the Editor-in-Chief 预览
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《地质学报:英文版》 SCIE CAS CSCD 2018年第3期I0002-I0002,I0001共2页
First of all, on behalf of the new Editorial Board, I would like to express our sincere appreciation foryour continuing support of our journal. This journal, founded in 1922, is the oldest geological journal in China.... First of all, on behalf of the new Editorial Board, I would like to express our sincere appreciation foryour continuing support of our journal. This journal, founded in 1922, is the oldest geological journal in China. As the flagship journal of theGeological Society of China, it has become more and more influential in earth sciences in China andbeyond. The journal is now indexed by SCI, CA and more than 20 other databases, with an impactfactor varying between 1.58 and 2.15 from year to year. It is co-published by the Geological Society ofChina and Wiley-Blackwell Co. 展开更多
关键词 MESSAGE Editor-in-Chief
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智能变电站过程层网络报文传输时间计算及抖动抑制方法 被引量:2
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作者 佟为明 高吉星 +1 位作者 金显吉 李中伟 《电力自动化设备》 CSCD 北大核心 2018年第6期131-137,共7页
过程层网络是智能变电站的重要组成部分,其实时性对智能变电站的安全可靠运行具有重要意义,而报文传输时间是实时性的主要指标。在介绍过程层网络结构及通信业务的基础上,提出了一种报文传输时间计算方法,分析了报文长度、数据率等因素... 过程层网络是智能变电站的重要组成部分,其实时性对智能变电站的安全可靠运行具有重要意义,而报文传输时间是实时性的主要指标。在介绍过程层网络结构及通信业务的基础上,提出了一种报文传输时间计算方法,分析了报文长度、数据率等因素对过程层网络中报文传输时间的影响并进行了仿真验证。针对因竞争而造成的采样值(SV)报文传输时间抖动问题,提出了一种通过控制报文发送时序与转发条件来抑制SV报文传输时间抖动的方法,给出了该方法的实现思路,仿真表明该方法可以在确保报文实时性的同时,有效地抑制SV报文传输时间的抖动。 展开更多
关键词 智能变电站 过程层网络 报文 实时性 报文传输时间
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