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100G Transport Systems: technology Bench-Mark Testing in China and Evolution to Terabit/s Interfaces

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China co.munications 2013年第4期10卷 19-30页

作者：张晓宏易小波刘翔 Peter J.Winzer Alcatel-Lucent shanghai Bell Alcatel-Lucent Bell Labs

To meet the exponentially growing demand fbr bandwidth in Optical Transport Networks （OTNs）, 100-Gb/s （100G） co.erent technology based oil Polarization-Division Multiplexed Quadrature Phase Shift Keying （PDM-QPSK）, which enables the capacity of a Wavelength Division Multiplexing （WDM） system to approach 10 Tb/s, is being widely deployed globally. As the first vendor to intro- duce a single-carrier 100G solution, A1- catel-Lucent has developed key transponder and network management technologies, which are reviewed in this paper together with their co.mercial evolution to 400G. Focusing on the Chinese market, we also review some key bench-mark testing results obtained in partner- ship with major Chinese operators. Finally, we discuss enabling technologies that are currently being researched to allow interfaces to scale to Terabit/s rates.

关键词： WDM transmission digital co.herent detection advanced modulation for-mats: wavelength monitoring superchannel

Modal analysis of subway tunnel in soft soil during operation

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Underground Space 2023年第1期8卷 181-195页

作者： Ling Wan Xiongyao Xie Lujun Wang Pan Li Qiang Huang co.lege of Civil Engineering and Architecture Nanchang Hangkong UniversityNanchang 330063China Jiangxi Transportation Institute co LtdNanchang 330200China Key Laboratory of Geotechnical and Underground Engineering Ministry of EducationTongji UniversityShanghai 20092China Center for Hypergravity Experimental and Interdisciplinary Research MOE Key Laboratory of Soft Soils and Geoenvironmental EngineeringCollege of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China Institute of Geotechnical Engineering Ningbo UniversityNingbo 315211China

Modal parameters are of great significance in civil engineering because they can characterize the properties of structures and be used for vibration co.trol and structural health *** tunnels are long linear truss structures co.bined with the mutual co.-pling of the surrounding ***,the operational modal analysis of a mutual co.pling tunnel is co.plicate,as is the modal iden-tification of shield tunnels in a time–frequency domain,and these are hot civil engineering *** the shield tunnel of shanghai metro line No.12 project as a case study,we carried out the vibration response monitoring of a subway tunnel during operation and presented methods to identify structural modal *** modal parameters of lower vibration modes were estimated using response *** frequencies and shapes were identified with high precision and accuracy using the orthogonal polynomial clustering algorithm under hammer excitation co.ditions and the autoregressive-moving-average model under ambient excitation *** dynamic behavior of a mutual co.pling tunnel presented obvious low frequency characteristics,and the first 9th order mode frequencies were less than 100 *** diagonal values of the modal assurance criteria were all greater than *** modal parameters can be used for the health monitoring of operational subway tunnels.

关键词： Monitoring method Modal identification Vibration response Operational subway tunnel

Multilevel Tests and Measurement Evaluation Methods for the Application of co.posite Materials in Spacecraft Structures

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上海航天（中英文） 2022年第1期39卷 111-121页

作者： WANG Yuhang GUO Liangshuai ZHOU Peng ZHANG Tao WANG Fuhui Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang 110819LiaoningChina Tianjin Aerospace Long March Rocket Manufacturing co. Ltd.Tianjin 300462China

With the implementation of new-generation launch vehicles,space stations,lunar and deep space exploration,etc.,the development of spacecraft structures will face new challenges. In order to reduce the spacecraft weight and increase the payload,co.posite material structures will be widely used. It is difficult to evaluate the strength and life of co.posite materials due to their co.plex mechanism and various phenomena in damage and ***,the structures of co.posite materials used in spacecrafts will bear co.plex loads,including the co.pling loads of tension,pressure,bending,shear,and torsion. Static loads,thermal loads,and vibration loads may occur at the same time,which asks for verification requirements to ensure the structure safety. Therefore,it is necessary to carry out a systematic multi-level experimental study. In this paper,the building block approach (BBA) is used to investigate the multilevel co.posite material structures for spacecrafts. The advanced measurement technology is adopted based on digital image co.relation (DIC) and piezoelectric and optical fiber sensors to measure the co.posite material structure deformation. The virtual experiment technology is applied to provide sufficient and reliable data for the evaluation of the co.posite material structures of spacecrafts.

关键词： co.posite material structure spacecraft multilevel test measurement evaluation

A Novel Subpixel Curved Edge Localization Method

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国际计算机前沿大会会议论文集 2015年第1期 36-37页

作者： Zhengyang Du Wenqiang Zhang Jinxian Qin Hong Lu Zhong Chen Xidian Zheng shanghai Engineering Research Center for Video technology and System School of Computer ScienceFudan UniversityP.R.China shanghai Key Lab of Intelligent Information Processing School of Computer ScienceFudan UniversityP.R.China shanghai Electric Group co. LTD. Central Academe

With the high-speed development of digital image processing technology, machine vision technology has been widely used in automatic detection of industrial products. A large amount of products can be treated by co.puter instead of human in a shorter time. In the process of automatic detection, edge detection is one of the most co.monly used methods. But with the increasing demand for detection precision,traditional pixel-level methods are difficult to meet the requirement, and more subpixel level methods are in the use. This paper presents a new method to detect curved edge with high precision. First, the target area ratio of pixels near the edge is co.puted by using one-dimensional edge detection method. Seco.d, parabola is used to approximately represent the curved edge. And we select appropriate parameters to obtain accurate results. This method is able to detect curved edges in subpixel level, and shows its practical effectiveness in automatic measure of products with arc shape in large industrial scene.

关键词： Machine vision curved edge detection subpixel parabola approximation.

Downlink Channel Estimation Algorithm in TD-LTE digital Relay Systems 14th

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Downlink Channel Estimation Algorithm in TD-LTE Digital Rela...

Key technology for Liquid Spawn Production and Green and High-yield Cultivation of Pleurotus eryngii

2012 IEEE 14th International co.ference on co.munication technology

作者： Jianfei Liu Jie Feng Mengjun Wang xiangye Zeng Jianpo Yang School of Information Engineering Hebei University of Technology Shenzhen Branch Allwin Telecommunication Co.LTD

ISBN: (纸本)9781467321006

In this paper,focusing on the downlink channel estimation of TD-LTE digital relay system,we present a new channel estimation method which is based on LS algorithm at scattered pilot frequencies with cascaded one-dimension linear interpolation both in time and frequency ***,different algorithms for channel estimation,such as LS and LMMSE,are investigated and co.parison of linear and DFT- based interpolation is *** analyzing co.puter simulation results,it is co.cluded that the proposed method has a good performance on estimating and tracking the variance of OFDM channel through co.paring with other channel estimation ***,it also achieves a lower bit error rate （BER） at a lower co.putational co.plexity.

关键词： TD-LTE digital relay channel estimation LS linear interpolation

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Asian Agricultural Research 2020年第7期12卷 52-54页

作者： Yali ZHANG Shuguang ZHAO Yu LI Zhengpeng LI Cuie ZHANG Xiaotao SUN Agricultural technology Extension Center of Guannan co.nty Guannan 222500 China Vegetable Office of Guannan co.nty Guannan 222500 China Institute of Edible Fungi Shanghai Academy of Agricultural Sciences Shanghai 201403 China Jiangsu Lisha Fungus Industry co. Ltd. Guannan 222500 China

[Objectives]Pleurotus eryngii is currently the seco.d largest edible fungus variety cultivated in China,and it mainly adopts the bag cultivation *** study aims to effectively solve the problems of high co.t of solid spawn,long spawn production cycle,low application level of green and high-yield cultivation technology and equipment,and unstable output and quality in the factory production process and to further promote industrial upgrading.[Methods]Since June,2018,a series of research and technical optimizations had been carried out by a technical research team co.sisting of personnels from Vegetable Office of Guannan co.nty,Institute of Edible Fungi of shanghai Academy of Agricultural Sciences and Jiangsu Xiangru Biotechnology co.,Ltd.,around the production of liquid spawn,introduction of excellent varieties of ***,medium pretreatment,autoclaving,clean room inoculation,digital cultivation,harvesting,packaging,etc.[Results]The key technology of industrial production,liquid spawn production and green and high-yield cultivation of *** are summarized.[co.clusions]The eco.omic benefit of liquid spawn of *** is extremely co.siderable co.pared with liquid spawns such as branch spawn.

关键词： Pleurotus eryngii Liquid spawn Factory cultivation Green High yield

Evaluation of the relationships and uncertainties of airborne and ground-based sea ice surface temperature measurements against remotely sensed temperature reco.ds

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International Journal of digital Earth 2022年第1期15卷 1989-2005页

作者： Pei Fan Xi Zhao Meng Qu Zhongnan Yan Ying Chen Zeyu Liang Xiaoping Pang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhanPeople’s Republic of China School of Geospatial Engineering and Science Sun Yat-Sen University & Southern Marine Science and Engineering Guangdong LaboratoryZhuhaiPeople’s Republic of China Key Laboratory of Polar Science MNRPolar Research Institute of ChinaShanghaiPeople’s Republic of China State Key Laboratory of Information Engineering in Surveying Mappingand Remote SensingWuhan UniversityWuhanPeople’s Republic of China Hubei Luojia Laboratory WuhanPeople’s Republic of China

Sea ice surface temperature(IST)is an important indicator of environmental changes in the Arctic *** this study,the relative performance of four mainstream IST reco.ds,*** IST,infrared radiometer measured IST(IR IST),longwave radiation derived IST(LWR IST),and snow and ice mass balance array buoy derived IST(Buoy IST),were evaluated against the MODIS IST ***,standard deviation(STD),and root mean square error(RMSE)were used to evaluate the data *** revealed that airborne IST had the best accuracy,which was 0.21 K co.der than MODIS IST,with STD of 1.46 K and RMSE of 1.47 ***-based ISTs were biased with each other but all warmer than the MODIS *** IR IST had the best overall accuracy(bias=0.55 K;STD=1.52 K;RMSE=1.61 K),while the LWR IST was the noisiest measurement with the largest outlier data ***,co.located IR and LWR ISTs were more co.sistent than any type of evaluated IST against MODIS IST(co.relation co.fficient=0.99).Airborne and IR ISTs are thus the premier choice for monitoring the rapidly changing Arctic sea ice,together with satellite observations.

关键词： Sea ice surface temperature airborne measurement in situ observation quality assessment the Arctic Ocean

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河口海岸数字孪生建设与挑战(特邀)

海洋技术学报 2023年第6期42卷 1-12页

作者：彭忠王长波刘利吕振华朱学明何青李武宋德海周烜武文柴扉彭伟彭伟 WANG Zhengbing YE Qinghua 华东师范大学河口海岸学国家重点实验室上海200241 华东师范大学计算机科学与技术学院上海200062 清华大学地球系统科学系北京100084 华东师范大学软件工程学院上海200062 南方海洋科学与工程广东省实验室(珠海) 广东珠海519085 中交第三航务工程勘察设计院有限公司上海200032 中国海洋大学物理海洋教育部重点实验室山东青岛266100 华东师范大学数据科学与工程学院上海200062 中国海洋大学海洋与大气学院山东青岛266100 厦门大学近海海洋环境科学国家重点实验室福建厦门361102 国家海洋技术中心天津300112 华东师范大学信息化治理办公室上海200062 Delft University of technology Delft 2628CJNetherlands Deltares Delft 2628CJNetherlands

河口海岸是人类生存的重要空间和经济发展的关键区域。然而,在气候变化和人类活动的双重压力下,河口海岸面临环境恶化、湿地生态受损和灾害风险增加等多重问题。为保障河口海岸可持续发展,本文以数字孪生概念为基础,结合河口海岸多圈层... 详细信息

河口海岸是人类生存的重要空间和经济发展的关键区域。然而,在气候变化和人类活动的双重压力下,河口海岸面临环境恶化、湿地生态受损和灾害风险增加等多重问题。为保障河口海岸可持续发展,本文以数字孪生概念为基础,结合河口海岸多圈层多界面的系统特征,提出了一个综合河口海岸立体监测和数据聚融、多过程耦合模型系统、数字孪生体和智能服务平台等关键要素的河口海岸数字孪生系统。此外,本文还详细介绍了构建河口海岸数字孪生系统所需的核心技术,涵盖监测物联网、模型耦合、大数据管理和智能分析,以及知识图谱等。尽管面临多学科全要素综合监测、人地海耦合模拟、跨领域跨行业协同、信息安全保障和服务标准制定等多重挑战,河口海岸数字孪生具有逼近真实、系统关联和提供智能服务等特点,能够提供监测、预报、预警、预演和预案等智能服务。这将有助于提高我们对河口海岸复杂系统演变、预测和应对的研究和应用能力,推动河口海岸学科群的发展,提升风险管理和综合治理水平,为河口海岸可持续发展提供强有力的支持。

关键词：河口海岸数字孪生人地海耦合立体监测网多过程耦合模型知识图谱可视化平台