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奥地利物理学家143公里打破量子远距传输纪录
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《黑龙江科技信息》 2012年第27期I0001-I0002,共2页
奥地利物理学家凭借143公里的成绩打破量子远距传输的最远距离纪录 新浪科技讯北京时间9月7日消息,据美国物理学家组织网6日报道,维也纳大学和奥地利科学院的物理学家凭借143公里的成绩打破量子远距传输的最远距离纪录。这项成就是... 奥地利物理学家凭借143公里的成绩打破量子远距传输的最远距离纪录 新浪科技讯北京时间9月7日消息,据美国物理学家组织网6日报道,维也纳大学和奥地利科学院的物理学家凭借143公里的成绩打破量子远距传输的最远距离纪录。这项成就是在朝着基于卫星的量子通讯道路上向前迈出的重要一步。研究成果刊登在《自然》杂志上。 展开更多
关键词 量子远距传输 物理学家 奥地利 公里 《自然》杂志 北京时间 量子通讯 研究成果
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对远距离高质量传输卫星广播下行信号方法的探讨 被引量:1
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作者 李远东 《有线电视技术》 2009年第2期43-46,共4页
本文提出"第一中频传输系统"与"广义系统噪声"等新提法;在此基础上,较详细地探讨了当卫星地球接收站的天线与室内接收机的距离较远时如何保证卫星数字广播信号的高质量接收。
关键词 传输系统 噪声 远距传输 信号质量
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基于LPWAN 偏远低效气井数据传输方案设计 被引量:2
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作者 赵咏 唐嘉 +1 位作者 韩涛 吴玙欣 《西南石油大学学报(自然科学版)》 CAS CSCD 北大核心 2020年第6期141-148,共8页
在国际低油价的背景下,经济高效地实现油气生产数字化转型和智能化发展,提高生产效率是油气企业持续发展的重要战略。天然气井生产数据的采集传输是实现生产预警、动态分析及降低人员劳动强度的有效手段,传统天然气井数据采集传输方案... 在国际低油价的背景下,经济高效地实现油气生产数字化转型和智能化发展,提高生产效率是油气企业持续发展的重要战略。天然气井生产数据的采集传输是实现生产预警、动态分析及降低人员劳动强度的有效手段,传统天然气井数据采集传输方案存在成本高、建设周期长及设备功耗高等问题,不适宜在偏远低效天然气井部署。通过对低功耗广域网(LPWAN)技术进行研究,总结技术优势,并结合偏远低效天然气井生产特点、环境配套及信息化需求,形成了具有针对性、经济可靠的、基于LoRa和NB IoT异构组网的数据传输方案。方案采用传感器采集气井生产数据并通过LoRa技术传输至采集传输模块,经过解析后通过NB IoT技术传输至云服务器,调控中心通过访问云服务器方式实现远程监控。根据本文方案对气井进行测试分析,结果表明,该方案设计高效率、低成本、低功耗地实现偏远低效天然气井数据采集传输,对传统信息化建设方案提供了有效补充。 展开更多
关键词 低功耗 低效天然气井 远距传输 降本增效
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利用CCD准确测量激光远场发散角 被引量:8
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作者 陈军 黄鹏 《强激光与粒子束》 EI CAS CSCD 北大核心 1997年第4期552-556,共5页
利用CCD面阵接收器,通过标定的方法,将其准确安置在长焦距透镜后焦面上,并找出CCD象元数与原场发散角的对应关系,从而迅速确定远场发散角。同时用短焦距透镜对光束限制光阑成像,测得近场光斑光强分布。以激光束振幅函数的傅... 利用CCD面阵接收器,通过标定的方法,将其准确安置在长焦距透镜后焦面上,并找出CCD象元数与原场发散角的对应关系,从而迅速确定远场发散角。同时用短焦距透镜对光束限制光阑成像,测得近场光斑光强分布。以激光束振幅函数的傅里叶变换作为理想衍射极限,将远场发散角与之比较,可以得到用几倍衍射极限的方法表示的实际光束质量。 展开更多
关键词 场发散角 CCD测量 激光质量 远距传输
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Quantum Standard Teleportation Based on the Generic Measurement Bases
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作者 HAOSan-Ru HOUBo-Yu +1 位作者 XIXiao-Qiang YUERui-Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4X期415-420,共6页
We study the quantum standard teleportation based on the generic measurement bases. It is shown that the quantum standard teleportation does not depend on the explicit expression of the measurement bases. We have give... We study the quantum standard teleportation based on the generic measurement bases. It is shown that the quantum standard teleportation does not depend on the explicit expression of the measurement bases. We have given the correspondence relation between the measurement performed by Alice and the unitary transformation performed by Bob. We also prove that the single particle unknown states and the two-particle unknown cat-like states can be exactly transmitted by means of the generic measurement bases and the correspondence unitary transformations. 展开更多
关键词 普通测量基数 远距传输 量子远距传输协议 单粒子未知态 量子信息理论 双粒子未知态
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基于AVR Atmega162和CS5534的高精度称重系统设计
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作者 徐法格 李岩 +3 位作者 孙金庆 周晨磊 刘汝华 周风余 《可编程控制器与工厂自动化(PLC FA)》 2014年第5期73-77,共5页
基于AVR Atmega162和24位高精度模数转换器CS5534的可应用于多场合的称重系统从硬件与软件两方面入手,阐述了称重传感器与CS5534的接口电路及使用、电源的隔离、多机通信的处理、滑动滤波算法的实现,以及称重数据的显示及传输方法。实... 基于AVR Atmega162和24位高精度模数转换器CS5534的可应用于多场合的称重系统从硬件与软件两方面入手,阐述了称重传感器与CS5534的接口电路及使用、电源的隔离、多机通信的处理、滑动滤波算法的实现,以及称重数据的显示及传输方法。实验结果表明,该系统精度高,稳定性好,适用于多种工作场合,有很大的市场价值。 展开更多
关键词 滑动平均滤波 CS5534 电源隔离 远距传输
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新一代监控系统──多媒体视频监控的发展 被引量:1
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作者 房子河 崔云红 《警察技术》 北大核心 1997年第4期6-8,共3页
关键词 多媒体监控系统 视频监控 多媒体技术 系统功能 远距传输 安全防范 系统组成 引入计算机 操作员 视频切换矩阵
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Probabilistic Teleportation of a Three-Particle State
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作者 FANGJian-Xing ZHUShi-Qun ZHANGRong CHENXian-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第5X期519-522,共4页
A scheme for teleporting a three-particle state is proposed when three pairs of entangled particles are used as quantum channels. Quantum teleportation can be successfully realized with a certain probability if the re... A scheme for teleporting a three-particle state is proposed when three pairs of entangled particles are used as quantum channels. Quantum teleportation can be successfully realized with a certain probability if the receiver adopts an appropriate unitary-reduction strategy. The probability of successful teleportation is determined by the smaller coefficients of the three entangled pairs. 展开更多
关键词 三粒子态 远距传输概率 纠缠粒子 单一衰减 量子输运 量子通道
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Teleportation of an Arbitrary Three-Particle State via Three EPR Pairs 被引量:8
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作者 FANGJian-Xing ZHUShi-Qun CHENXian-Feng ZHANGRong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期369-372,共4页
A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the origi... A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the original state with deterministic probability can be reconstructed by the receiver when a corresponding unitary transformation is followed. 展开更多
关键词 TELEPORTATION arbitrary three-particle state three-entangled particle pairs unitary transformation
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Scheme for Teleportation of an Unknown Frequency State by Using an Acousto-optical Modulator 被引量:1
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作者 XIANG Shao-hua, YANG Xiong, SONG Ke-hui(Dept.of Phys.,Huaihua College, Huaihua 418008, CHN) 《Semiconductor Photonics and Technology》 CAS 2003年第2期116-118,共3页
A very simple scheme is presented for teleporting an unknown frequency state with the successful probability of 50%. Two acoustic-optical modulators and four narrow band photodetectors in the proposed scheme are used.... A very simple scheme is presented for teleporting an unknown frequency state with the successful probability of 50%. Two acoustic-optical modulators and four narrow band photodetectors in the proposed scheme are used. One advantage of our scheme is that no Bell-state measurement is need and no any unitary transformation is performed. 展开更多
关键词 quantum teleportation frequency entanglement acousto optical modulator
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Teleportation of Two-Mode Quantum State of Continuous Variables 被引量:1
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作者 SONGTong-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期362-364,共3页
Using two Einstein-Podolsky Rosen pair eigenstates |η) as quantum channels, we study the teleportationof two-mode quantum state of continuous variables.
关键词 TELEPORTATION EPR pair eigenstate generalized two-mode squeezed vacuum
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Conclusive Teleportation of an Arbitrary Three-Particle State via Positive Operator-Valued Measurement
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作者 LIU Hong XIAO Xiao-Qi LIU Jin-Ming 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期69-72,共4页
We present a scheme for conclusive teleportation of an arbitrary and unknown three-particle state by per-forming three Bell-state measurements at the sender's side and a positive operator-valued measurement at the... We present a scheme for conclusive teleportation of an arbitrary and unknown three-particle state by per-forming three Bell-state measurements at the sender's side and a positive operator-valued measurement at the receiver'sside.Moreover,we obtain the successful probability of teleportation and make a brief discussion on the average fidelityfor the conclusive teleportation scheme. 展开更多
关键词 TELEPORTATION three-particle state positive operator-valued measurement FIDELITY
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On Issues of Large-Scale and Long-Distance Transmission of Wind Power
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作者 Wang Ningbo 《Electricity》 2011年第2期41-44,共4页
While having constantly developed for five years,China's wind power meets its bottleneck of further development in fast-growing areas due to the insufficient market accommodation.In contrast,the Central China and ... While having constantly developed for five years,China's wind power meets its bottleneck of further development in fast-growing areas due to the insufficient market accommodation.In contrast,the Central China and the East China have experienced the shortage of coal,oil and natural gas for power generation in recent winters.Hence,how to handle the discrepancy between insufficient accommodation and short energy supply has become the focus of attention both domestically and abroad.Taking Jiuquan Wind Power Base as an example,the reverse distribution between the energy resources and the consumer market,the wind power accommodation and the energy transmission are analyzed;the necessity and feasibility of long-distance power transmission are also discussed,which presents a technical roadmap for the long-distance transmission of thermal and wind power in combination. 展开更多
关键词 large-scaled wind power energy resources TRANSMISSION RESEARCH
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科技热词
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《科学家》 2017年第22期132-133,共2页
【量子隐形传态】量子隐形传态(Quantum?teleportation),又称量子遥传、量子隐形传输、量子隐形传送、量子远距传输或量子远传,是一种利用分散量子缠结与一些物理讯息的转换来传送量子态至任意距离的位置的技术。是一种全新的通信方式。
关键词 量子隐形传态 量子隐形传送 科技 量子隐形传输 量子远距传输 量子缠结 通信方式 量子态
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Organochlorine Pesticides(OCPs) in Soils Along the Eastern Slope of the Tibetan Plateau 被引量:14
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作者 XING Xin-Li QI Shi-Hua +2 位作者 ZHANG Yuan YANG Dan J. O. ODHIAMBO 《Pedosphere》 SCIE CAS CSCD 2010年第5期607-615,共9页
Soil samples collected from several sites along an altitudinal transect on the eastern slope of the Tibetan Plateau were analyzed for hexachlorobenzenes(HCHs) and dichlorodiphenyltrichloroethanes(DDTs).The results sho... Soil samples collected from several sites along an altitudinal transect on the eastern slope of the Tibetan Plateau were analyzed for hexachlorobenzenes(HCHs) and dichlorodiphenyltrichloroethanes(DDTs).The results showed that HCHs and DDTs were found in the soil samples from the remote high altitude areas away from source regions,which confirmed the long-range atmospheric transport phenomenon of these organochlorine pesticides(OCPs) insecticides.The OCP concentrations in the soils had a significant negative correlation with altitude;they showed a trend to increase with decreasing altitude,but the increase was not continuous,being interrupted at some moderate-altitude sites on the transect.The distances from the source region,landforms,soil properties,and physical-chemical properties of OCPs were more important than total organic carbon content to the distribution of OCPs in soils disturbed by human activities.An analysis of the compositions of HCH isomers and DDTs revealed predominantly low ratios of α-HCH to γ-HCH,ranging from 0.06 to 4.79,which suggested current lindane inputs.On the other hand,low p,p-DDT/p,p-DDE and o,p-DDT/p,p-DDT ratios were observed,indicating mainly aged historical DDT residues in the study area. 展开更多
关键词 ALTITUDE DICHLORODIPHENYLTRICHLOROETHANE HEXACHLOROBENZENE long-range atmospheric transport
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Background concentrations of reactive gases and the impacts of long-range transport at the Jinsha regional atmospheric background station 被引量:8
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作者 LIN WeiLi XU XiaoBin +2 位作者 SUN JunYing LIUXiWen WANG Ying 《Science China Earth Sciences》 SCIE EI CAS 2011年第10期1604-1613,共10页
Lorentz curve fittings are applied to frequency distributions of the concentrations of O3, CO, NOx and SO2 recorded at the Jinsha regional atmospheric background station (JSH) from June 2006 to July 2007, and the pe... Lorentz curve fittings are applied to frequency distributions of the concentrations of O3, CO, NOx and SO2 recorded at the Jinsha regional atmospheric background station (JSH) from June 2006 to July 2007, and the peak concentrations of these species for the different seasons are obtained. The peak concentrations are considered to be representative of different background levels for certain processes. The peak concentrations are compared with the corresponding mean (median) concentrations, and the suitability and limitations of the mean (median) values as the background levels are discussed. The mean (median) values might represent the background concentrations in the region under some circumstances, but in other cases these values often underestimate or overestimate the true background concentrations owing to the transport of pollutants and other factors. The effects of air masses transported from different regions on the pollutant background concentrations are obtained by analyzing the 72-hour backward trajectories of air masses 100m above the ground at JSH, These trajectories are estimated using the HYSPLIT model and then clustered for the measurement period. The spatial distribution and seasonal variations of trajectories and the corresponding mean concentrations of O3, SO〉 NOx and CO for different clusters are analyzed. After filtering the seasonal changes in pollutant concentrations, the relative influences of air masses from different regions are obtained. The results show that JSH can be used to obtain the atmospheric background information of different air masses originating from or passing over the Yangtze River Delta, Central South China and the Jianghan Plain. Air masses from Central China, South China, and the western Yangtze River Delta contribute significantly to O3 at JSH. Air masses from the north and northeast of JSH (i.e., the Jianghan Plain, Huang-Huai Plain and North China Plain) and the south (Central South China) contribute significantly to SO2, CO and NOx concentrations. Air masses originating from the ocean often bring clean air. Air masses originating from high altitudes over northwestern regions often have lower CO and NO3 concentrations, lower relative humidity, and higher concentrations of O3 and SO2. 展开更多
关键词 Jinsha regional atmosphere background station background signal Lorentz curve fitting air transport O3 CO NOx SO2
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Blade Tip Timing Vibration Monitoring Method Based on Fiber Bragg Grating 被引量:1
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作者 Fei WU Lei LIANG Junya XING Lin WANG Lang JIA 《Photonic Sensors》 SCIE EI CAS 2014年第2期188-192,共5页
The ventilators have been vividly called "the lungs of mine". The rotating blades are the core parts of a ventilator, they can influence the safety and reliability of the ventilator. This paper will use the tip-timi... The ventilators have been vividly called "the lungs of mine". The rotating blades are the core parts of a ventilator, they can influence the safety and reliability of the ventilator. This paper will use the tip-timing method based on the fiber Bragg grating magnetically coupling sensor to study and analyze the ventilator blade vibration, in order to realize long-distance and non-contact real-time online safety monitoring of blade vibration. Compared with the electronic sensorand fiber intensity reflective sensor, the fiber grating coupling magnetic sensor has such advantages as explosion-proof, working at harsh environment with humid air, dust and greasy dirt, capable of achieving long-distance signal transmission, and joining easily with other fiber Bragg grating sensors to form a network in order to achieve multi-parameter distributed online monitoring. 展开更多
关键词 Blade vibration fiber Bragg grating magnetic coupling SENSOR
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Long-range adiabatic quantum state transfer through a linear array of quantum dots 被引量:5
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作者 CHEN Bing SHEN QingHui +1 位作者 FAN Wei XU Yan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第9期1635-1640,共6页
We introduce an adiabatic long-range quantum communication proposal based on a quantum dot array.By adiabatically varying the external gate voltage applied on the system,the quantum information encoded in the electron... We introduce an adiabatic long-range quantum communication proposal based on a quantum dot array.By adiabatically varying the external gate voltage applied on the system,the quantum information encoded in the electron can be transported from one end dot to another.We numerically solve the schr dinger equation for a system with a given number of quantum dots.It is shown that this scheme is a simple and efficient protocol to coherently manipulate the population transfer under suitable gate pulses.The dependence of the energy gap and the transfer time on system parameters is analyzed and shown numerically.We also investigate the adiabatic passage in a more realistic system in the presence of inevitable fabrication imperfections.This method provides guidance for future realizations of adiabatic quantum state transfer in experiments. 展开更多
关键词 adiabatic passage tight-binding model quantum state transfer
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