Impact of Coronavirus Pandemic Crisis on Technologies and Cloud Computing Applications

In light of the coronavirus disease 2019 (COVID-19) outbreak caused by the novel coronavirus, companies and institutions have instructed their employees to work from home as a precautionary measure to reduce the risk of contagion. Employees, however, have been exposed to different security risks because of working from home. Moreover, the rapid global spread of COVID-19 has increased the volume of data generated from various sources. Working from home depends mainly on cloud computing (CC) applications that help employees to efficiently accomplish their tasks. The cloud computing environment (CCE) is an unsung hero in the COVID-19 pandemic crisis. It consists of the fast-paced practices for services that reflect the trend of rapidly deployable applications for maintaining data. Despite the increase in the use of CC applications, there is an ongoing research challenge in the domains of CCE concerning data, guaranteeing security, and the availability of CC applications. This paper, to the best of our knowledge, is the first paper that thoroughly explains the impact of the COVID-19 pandemic on CCE. Additionally, this paper also highlights the security risks of working from home during the COVID-19 pandemic.     

基于ZigBee无线通信技术的智能家居系统

ZigBee是一种新兴的短距离无线通信技术,专为低速率、低功耗的无线互联应用而设计,非常适合家庭无线组网.分析了智能家居的特点,并着重剖析了ZigBee技术及其特点,介绍了一种基于ZigBee技术的智能家居系统,重点阐述了该系统的组成、家庭网关以及无线节点的设计.该系统在实际应用中,运行稳定可靠.     

Comparison of CEPA and CP-MET methods

The known CEPA variants CEPA (v) withv = 0,1,2,3 and two new ones withv = 4, 5 are compared both formally and for various numerical examples with CP-MET. The main conclusions are: 1. In those situations where both CP-MET and the CEPA variants are justified (i.e. for “good” closed shell states) the correlation energies obtained with the 7 different schemes differ very little (by something like ±2%), with CEPA (1) closest to CP-MET (difference usually a fraction of 1%) and CEPA (4) nearly as close; this is rather insensitive to whether one uses canonical or localized orbitals. Even CEPA (3) is not too far from CP-MET, which confirms an earlier suggestion of Kelly. 2. In those cases where one of the 7 schemes fails (e.g. due to near degeneracy as in covalent molecules at large internuclear distances) the other 6 usually fail as well, though CEPA (0) is then somewhat poorer than the other schemes. Then no longer CEPA (1) but rather CEPA (3) is closest to CP-MET and then all schemes converge much better in a localized representation. 3. CEPA (2) usually leads to best agreement with experiment since it simulates to some extent triple substitutions. In none of the studied examples does CP-MET show a significant superiority as compared to the other schemes. Possible improvements to extend the domain of applicability of these methods are discussed.     

一种用于移动终端的联合信道译码器

对移动终端中使用的信道译码技术进行了介绍，指出未来的移动终端需要支持多种通信标准。设计了一种用于移动终端的联合信道译码器，可支持多种通信标准，达到最大限度利用共享资源，从而节省总体成本。     

脑电信号无线采集系统设计

介绍一种应用于可穿戴式无线脑电信号采集系统设计方案。系统控制器采用16位的MSP430F169单片机,其内部的12位A/D对放大滤波后的脑电信号进行采集,然后通过SPI口将采集到的16通道的脑电信号数据写入到CC2500的寄存器中发射出去,接收端同样通过单片机将CC2500的接收寄存器中数据读出,再由UART通过USB转换芯片传入计算机用于显示和进一步的分析处理。该系统有着低功耗和便携式等优点。     

基于ZigBee的无线测温管理系统的应用研究

为及时测量变电站运行设备中大电流回路连接点发热的温度,设计出一种基于ZigBee技术的无线测温管理系统。详细阐述了无源传感器节点的工作原理和实现方案,给出了硬件电路设计和系统软件构成。通过可视化程序设计语言Visual Basic 6.0设计的监控界面,易于实现无线传感器网络温度信息的实时采集、及时报警和有效管理,做到设备发热实时监控及远距离遥测。     

基于ZigBee技术的热计量远程抄表系统研究

目前,在集中采暖的住宅小区中,正在推行按热量计量的收费方式改革。在此背景下,创造性地提出一种基于ZigBee技术的热计量远程抄表系统设计方案,叙述了ZigBee协议以及系统的硬件和软件流程。系统利用ZigBee芯片CC2430、温度传感器、流量传感器、热量积分仪设计出具备无线传输功能的热计量表,并采用无线自组网与GPRS相结舍的方式,对集中供暖热水流量和温度进行远程抄表。使用结果证明,该系统具备操作方便、成本低廉、功耗低等诸多优点,因而具有广阔的应用前景。创新之处在于紧密结合当前应用实际,采用ZigBee技术组织无线自组网,对热量计量进行远程传输。     

基于CC2430的无线传感器网络系统设计

介绍一种基于CC2430的无线传感器网络系统设计,它以CC2430为核心,用于监控温湿度、红外线强度、光照度的无线传感器网络。给出了系统的总体结构、硬件电路、软件设计以及电路板、数据结果。     

ZigBee星形网络在动物机器人中的应用

本文首先介绍了动物机器人的基本原理及实验方法。针对动物机器人特点,我们选择ZigBee协议作为多动物机器人通信协议,利用该协议支持自组网络的功能,由一个协调器和多个终端节点来组建星形无线网络,基于此描述动物机器人节点的基于CC2430的具体硬件设计和软件的实现过程。     

卷积码中运用交织器实现不等错误保护

在数字通信系统中,发送的数据序列中的比特往往具有不等的重要性。为了寻求更可靠的信息传输,人们提出了一些不等错误保护(UEP)编码方案。分析了卷积码潜在的UEP性能,并通过量化、交织器以及最佳卷积码(CC)的综合设计,在CC的基础上实现UEP。仿真结果表明,在卷积码的基础上运用交织器的编码器设计方案,可以获得较好的交织增益,从而改善编码器的性能。