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31971.在回路成套系统实验室测试中使用500千瓦功率硬件的先进光伏逆变器的功能
[电力、热力、燃气及水生产和供应业,计算机、通信和其他电子设备制造业] [2014-09-25]
With the increasing penetration of distribution connected photovoltaic (PV) systems, more and more PV developers and utilities are interested in easing future PV interconnection concerns by mitigating some of the impacts of PV integration using advanced PV inverter controls and functions. This paper describes the testing of a 500 kW PV inverter using Power Hardware-in-Loop (PHIL) testing techniques. The test setup is described and the results from testing the inverter in advanced functionality modes, not commonly used in currently interconnected PV systems, are presented. PV inverter operation under PHIL evaluation that emulated both the DC PV array connection and the AC distribution level grid connection are shown for constant power factor (PF) and constant reactive power (VAr) control modes. The evaluation of these modes was completed under varying degrees of modeled PV variability.
关键词:光伏电源;逆变器;网格;互联电力系统
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31972.全球智能手机射频功率放大器市场报告(2014-2018年)
[计算机、通信和其他电子设备制造业] [2014-09-25]
A RF power amplifier is a semiconductor device that converts electrical signals into radio signals. These amplifiers use a transistor to consume less power in either an output signal mode or a standby mode.
关键词:智能手机;射频功率放大器;市场前景
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31973.2014年1-8月中国通信行业运行分析
[计算机、通信和其他电子设备制造业] [2014-09-25]
2014年8月份,全国电信业务总量完成1528.1亿元,同比增长14.7%,比7月回升0.1个百分点;电信主营业务收入完成998.7亿元,同比增长3.3%,比7月回落1.3个百分点,主营业务收入增长乏力。2014年1-8月,全国电信业务总量累计完成11660.2亿元,同比增长15.0%,增速与1-7月持平;电信主营业务收入累计完成7924.1亿元,同比增长6.2%,比1-7月下降0.4个百分点,再次延续同比增速持续回落的趋势。
关键词:通信行业;运行分析
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31974.机器人米尔斯多通道交互
[信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-09-24]
关键词:机器人;算法;控制系统;相互作用
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31975.基于超级小电脑的机器人的语音控制系统
[计算机、通信和其他电子设备制造业,信息传输、软件和信息技术服务业] [2014-09-24]
Raspberry Pi is a credit card sized Linux computer based on ARM11 architecture.Because of its small size,low power consumption and powerful performance,a robot controller is a suitable role for it to play.As a robot with artificial intelligence,speech recognition for controlling the robot and voice feedback to users is key parts of the entire system.In this essay,a robot called Lisa is assembled,and a speech control and interactive system is implemented based on Google voice API which is a voice recognition engine provided as a cloud service.In order to analysis complex voice commands,a semantic method is developed to catch key words from command sentences.Then try to make a pattern match between key words and instruction set build-in the robot control system.The speech recognition control and interactive system is effective and well behaved after experimental verification.
关键词:ASR;TTS;树莓丕;机器人
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31976.基于FPGA的执行解码器的有效准循环LDPC码
[信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-09-24]
Designers are increasingly relying on FPGA-based emulation to evaluate the performance of LDPC codes.In this paper,we propose a novel approximate lower triangular structure for the parity part of the parity-check matrix of QC-LDPC codes.Next,a high speed partially parallel decoder architecture which based on the Offset BP-based decoding algorithm is proposed.The results indicate that the frequency can reach 100MHz and its throughput rate can reach 113Mbps.
关键词:近似下三角结构的LDPC;失调基于BP译码算法; FPGA
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31977.用于实现第508条合规APEX应用程序的技术
[信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-09-24]
508 refers to Section 508 of the Rehabilitation Act of 1973 that was later expanded by the Workforce Investment Act of 1998. The act requires that when Federal agencies develop, procure, maintain, or use electronic and information technology, they must ensure that it is accessible to people with disabilities.
关键词:计算机网络;联邦机构;信息服务;信息技术
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31978.基于牛顿迭代定位算法的无线传感器网络的研究
[计算机、通信和其他电子设备制造业,信息传输、软件和信息技术服务业] [2014-09-24]
The TDOA localization algorithm for wireless sensor networks can help us measure the time differences of an unknown node to more anchor nodes,which establish nonlinear equation of the differential distance between unknown node and anchor node.Newton iteration is the crucial method for nonlinear equation numerical solutions,so using the Newton iterative method can better achieve nonlinear optimization in TDOA location.The simulation results indicate that the algorithm can meet the requirement of localization and possesses the preferable localization precision.
关键词:无线传感器网络;牛顿迭代法;非线性;到达时间差
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31979.基于MATLAB的几种PID算法的研究
[信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-09-24]
This paper introduces several PID control algorithms and their discretization expression.Compare the performance of positional PID algorithm with incremental PID algorithm,integration separate PID algorithm,incomplete differential PID algorithm and PID algorithm with dead zone.The experiment results show that different digital PID control algorithm could achieve different using.
关键词:位置式PID;增量式PID;整合独立PID;不完全微分PID;电子信息
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31980.海面上方的基于方向频谱的海洋波浪产生的磁场干扰模拟
[信息传输、软件和信息技术服务业,计算机、通信和其他电子设备制造业] [2014-09-24]
Ocean wave have a magnetic field disturbance,caused by the motional induction of sea water moving in the steady main field of Earth.Mass experiment indicates ocean wave-generated magnetic field disturbance can be a major limitation on the performance of airborne magnetic anomaly detection.To check the character of such disturbance observed above sea-surface,a harmonic ocean wave-generated magnetic field disturbance mathematical model based on Weaver's monochromatic wave-generated magnetic field model and ocean wave directional spectrum is proposed.Algorithm is presented for real-time simulation of ocean wave-generated magnetic field disturbance corresponding to the proposed mathematical model.Numerical simulations of ocean wave-generated magnetic field disturbance are sampled above sea-surface by a stationary magnetometer and an airborne magnetometer moving steadily along a rectilinear path.Spectrum analysis of the samples is performed.Simulations results indicate that the proposed harmonic ocean wave magnetic field disturbance mathematical model can well-simulate the real sea conditions.Numerical simulations also reveal that there is a Doppler frequency shift with the increase of magnetometer flight speed.Moreover,energy of the magnetic field disturbance is more dispersed and frequency band is wider with the increase of magnetometer flight speed.
关键词:磁场干扰;方向谱;磁异常探测;功率谱密度