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Heterogeneous cellular network optimization for green access of IoT traffics [PDF]
The Internet of Things (IoT) has become an essential supporting platform for the present and future cyber-enabled services. Cellular networks is considered as the main channel of the data access for IoT terminals distributed in the region of interest ...
Wei HUANGFU, Ya-xi LIU
core +1 more source
Research on router device of OAM optical communication [PDF]
With the development of orbital angular momentum (OAM) based optical communication technology,OAM router played an important role in improving the flexibility and practicability of OAM communication system.In recent years,the research on multifunctional ...
Chaofan GONG +5 more
core +1 more source
Horn Antenna Gain Measurement Based on Vector Network Analyzer [PDF]
利用微波暗室、矢量网络分析仪、角锥喇叭天线以及电脑等设备建立了一套喇叭天线测量系统;采用两相同天线法,分别测量了4~6 GHz、6~8 GHz角锥喇叭天线的增益值,对测量数据进行误差分析和近距修正;并将增益的实测值与理论计算值进行对比.实验结果表明,近距修正后,所测量的4~6 GHz与6~8 GHz频段天线的增益实测值与理论值的最大偏差值分别为-0.20 dB和-0.19 dB,均在±0.25 dB范围内,符合标准增益天线增益的精度要求,也与天线出厂的指标相符 ...
刘汝兵, 刘震, 周严东, 林麒
core +1 more source
目的 本国际临床指南由欧洲残疾儿童学会(the European Academy of Childhood Disability,EACD)牵头制定,旨在解决发育性协调障碍(developmental coordination disorder,DCD)的定义、诊断、评估、干预以及与社会心理方面的临床应用关键问题。 方法 本指南针对五个领域的关键问题,通过文献综述和专家团队的正式讨论达成共识。为保证指南的循证基础,以“机制”、“评估”和“干预”为检索词, 对2012年更新以来提出的最新建议以及新增的“社会心理问题”和“青少年/成人”为检索词进行检索。根据牛津大学循证医学中心证据等级 (证据水平 [level of evidence, LOE]1–4) 将结果进行分类,最终转化为指南建议。并由国际 ...
Jing Hua +6 more
wiley +1 more source
Energy efficient resource allocation scheme for AF relay downlink system [PDF]
In order to maximize the total energy efficiency of amplify-and-forward relay downlink system,a joint scheme of relay selection and power allocation was proposed with the circuit power of the system.For reducing the computa-tional complexity,a step-by ...
Bo HUANG, Xu-ming FANG, Yu CHEN
core +1 more source
单芯电缆的结构参数和运行环境影响都会导致电缆的无功损耗变化。为了探究单芯电缆结构和运行环境对电缆无功损耗的影响,文中从电缆内部结构出发,建立了电缆等效电路模型。通过分析电缆内部无功损耗形式,研究了单芯电缆在特殊工况下的无功损耗变化情况。结果表明:单端接地电缆内部损耗以容性无功损耗为主;电缆电压等级越高时,输送一定功率的极限传输距离反而越短,并给出了66、110、220、330、500 kV电缆的极限传输距离;电缆内部进水后容性无功损耗会增大10%~30%,电压等级越高或者电缆截面积越大 ...
李瑞芳 +5 more
doaj
Joint energy efficiency and spectral efficiency optimization algorithm for UDN under the restriction of interference threshold and backhaul capacity [PDF]
Aiming at the scenarios which consider the constraint of backhaul capacity restriction and interference threshold in ultra-dense networks (UDN),an integer linear programming (ILP) and Lagrangian dual decomposition (LDD) based joint optimization algorithm
Xu CHEN, Xuanli WU
core +1 more source
Design and research of adaptive O-OFDM symbol decomposing with serial transmission system in visible light communication [PDF]
Iterative signal clipping (ISC) and symbol decomposing with serial transmission (SDST) techniques decompose optical orthogonal frequency division multiplexing (O-OFDM) symbol into the fixed number of multiple small-amplitude symbols.However,at low O-OFDM
Boran YANG +4 more
core +1 more source
准确计算换流阀及其中各类元部件运行损耗,是进行换流阀及其阀冷系统设计的基础。文中在分析换流阀中主要损耗源基础上,建立了晶闸管、电抗器的高精度等效仿真模型,提出了换流阀损耗的仿真计算方法。以此为基础,计算了额定工况下锡盟站换流阀中各主要元部件损耗功率,并将总损耗计算结果与理论计算值及现场测试数据进行了对比分析。结果表明:仿真方法具有较高精度,可被用于换流阀总损耗计算,以及阀内各发热器件的功率计算。
娄彦涛, 袁妮, 刘琦
doaj
MOV静态下的功率损耗是影响其热稳定的重要因素,在考虑了老化因素对MOV功率损耗的影响后提出了老化程度变量并将其量化的新方法,并利用自适应模糊推理系统(ANFIS)将电压(V)、温度(T)、老化程度(AD)作为网络的输入,实验测量数据作为训练样本对MOV的功率损耗进行评估。研究表明:ANFIS可有效评估MOV的功率损耗,其最大相对误差为8.
牛春霞, 于忠江, 杨仲江
doaj

