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11.
随着中国经济与社会的快速发展,环境监测引起人们的广泛关注。为了解决目前监控系统的不足,设计一种基于ZigBee和因特网的智能远程监控系统。该系统采用TI公司的CC2530芯片及相应传感器构建ZigBee局域网,将采集到的温湿度信息,经过上位机存储并处理,利用因特网或无线移动网络,在安卓智能手机终端上实现数据的远程传输。通过上位机与手机终端,可以查看当前环境状态,保存历史数据,并进行自动报警。给出系统硬件及软件实现方法,包括节点设计、组网流程、数据传输功能、上位机软件设计、安卓智能手机终端软件设计等。实验测试结果说明该系统工作稳定、容易扩展、上位机及手机操作简便。 相似文献
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本文详细介绍了技术质量部对用户厂家反映我公司25FS管莫尔条纹的问题进行的深入探究,发现其产生的三大主要物理原因,并作了适当的数学说明,并提出了相应的对策. 相似文献
14.
Ziyad R. Alashhab Mohammed Anbar Manmeet Mahinderjit Singh Yu-Beng Leau Zaher Ali Al-Sai Sami Abu Alhayja’a 《电子科技学刊:英文版》2021,19(1):25-40
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. 相似文献
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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. 相似文献
17.
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。 相似文献
18.
在G2 (CC ,MP2 )理论水平上研究了C2 (a3 Πu)自由基与NO分子的反应 .计算了反应体系最低二重态势能面上各驻点的构型参数、振动频率和能量 ,揭示了此反应存在两种反应机理 :由NO中的O原子进攻C2 自由基形成CCON中间体的CCON机理和NO中的N进攻C2 自由基形成CCNO中间体的CCNO机理 ,分析了对应与这两种反应机理的五个可能的反应通道 ,得出了由NO中的N原子进攻3 C2 自由基 ,生成中间体CCNO自由基 ,最终得到产物CN +CO的通道是最有利的通道 . 相似文献
19.
Exact solutions for nonlinear Schr?dinger equation in phase space: applications to Bose-Einstein condensate 下载免费PDF全文
The stationary-state nonlinear Schr?dinger equation, which models the dilute-gas Bose-Einstein condensate, is introduced within the framework of the quantum phase-space representation established by Torres-Vega and Frederick. The exact solutions of equation are obtained in the phase space, by means of the wave-mechanics method. The eigenfunctions in position and momentum spaces are obtained through the ‘Fourier-like' projection transformation from the phase space eigenfunctions. The eigenfunction with a hypersecant part is discussed as an example. 相似文献
20.
Ground state properties of a Bose-Einstein condensate confined in an anharmonic external potential 下载免费PDF全文
In light of the interference experiment of Bose-Einstein condensates, we present an anharmonic external potential model to study ground state properties of Bose-Einstein condensates. The ground state energy and the chemical potential have been analytically obtained, which are lower than those in harmonic trap. Additionally, it is found that the anharmonic strength of the external potential has an important effect on density and velocity distributions of the ground state for the Thomas-Fermi model. 相似文献