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小断面膨胀性软岩隧洞一次支护及二次衬砌承载能力分析

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水利水电工程设计 2024年第1期43卷 39-42,72页

作者：王汉明田新星蔡元成中水北方勘测设计研究有限责任公司天津300222

我国在引调水及灌区工程建设过程中,各类软弱围岩隧洞已屡见不鲜。因膨胀性软弱围岩工程性质的特殊性,隧洞施工中经常面对支护结构破坏甚至失稳、大变形等难题。软弱性围岩隧洞以整体变形破坏为主,建立了一次支护数值模型,拟定了不同围... 详细信息

我国在引调水及灌区工程建设过程中,各类软弱围岩隧洞已屡见不鲜。因膨胀性软弱围岩工程性质的特殊性,隧洞施工中经常面对支护结构破坏甚至失稳、大变形等难题。软弱性围岩隧洞以整体变形破坏为主,建立了一次支护数值模型,拟定了不同围岩支护时机及支护措施,通过模拟计算,隧洞围岩收敛变形在规范允许范围内,一次支护措施承载能力满足施工期安全要求,为施工期各类围岩支护时机及支护措施提供了理论依据。建立二次衬砌数值模型,考虑隧洞运行期内水外渗引起的围岩吸水膨胀,剖析不同工况下二次衬砌的力学响应特征,结果表明二次衬砌底板是受力最不利位置,可通过提高底板的厚度或配筋量,提高衬砌整体承载力。本研究可为膨胀性软岩隧洞支护衬砌结构设计提供理论指导,为同类工程设计及施工提供参考。

关键词：软岩隧洞膨胀性 LDP曲线承载能力有限元分析

甘肃省区域自动气象站数据质量评估应用程序研究

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青海科技 2024年第1期31卷 138-143页

作者：陈秀花孔令旺蔡元成甘肃省气象信息与技术装备保障中心兰州730020 甘肃省气象局兰州730020

文章利用python编程语言开发了一款对甘肃省区域自动气象站质控疑误数据自动统计分析应用程序,能够自动链接甘肃省气象资料业务系统(MDOS)区域自动站后台数据库,对全年各月质控出的全省区域自动站疑误数据进行分站点、分要素、分疑误类... 详细信息

文章利用python编程语言开发了一款对甘肃省区域自动气象站质控疑误数据自动统计分析应用程序,能够自动链接甘肃省气象资料业务系统(MDOS)区域自动站后台数据库,对全年各月质控出的全省区域自动站疑误数据进行分站点、分要素、分疑误类型的筛选、分析,快速自动生成EXCEL统计图形和表格,自动生成WORD格式的甘肃省区域站逐月数据质量分析报告模板;程序的业务应用对提高区域站设备运行的可靠性和数据可用性具有重要意义。

关键词：区域自动气象站数据质量评估应用程序

Ultra-wideband fiber-THz-fiber seamless integration communication system toward 6G: architecture, key techniques, and testbed implementation

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Science China(Information Sciences) 2023年第1期66卷 296-313页

作者： Min ZHU Jiao ZHANG Bingchang HUA Mingzheng LEI yuancheng cai Liang TIAN Dongming WANG Wei XU Chuan ZHANG Yongming HUANG Jianjun YU Xiaohu YOU National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories School of Information Science and Technology Fudan University Peng Cheng Laboratory

Terahertz(THz) communication is widely regarded as the key component of future 6G mobile communication systems. Through comparative analysis of some of the main existing technical routes of THz up-conversion and down-conversion in THz wireless communication systems, a novel ultra-wideband(UWB)fiber-THz-fiber seamlessly converged real-time architecture, which utilizes the commercially mature digital coherent optical module to realize ultrahigh-capacity THz real-time wireless communication, is proposed in this study.(1) The proposed architecture employs the dual-polarization photonic up-conversion technique for THz generation and hybrid optoelectronic down-conversion technique for THz reception to facilitate the seamless integration between optical fiber and THz communications.(2) Because of the limited bandwidth of optoelectronic devices, multidimensional modulation techniques are adopted for UWB THz signals to improve spectral efficiency and transmission capacity.(3) An intelligent nonlinear joint compensation technique based on the deep neural network, which can effectively improve the signal-to-noise ratio of the time-varying hybrid fiber-THz-fiber channel, is proposed. Based on the investigations of the aforementioned key techniques, we, for the first time, realize the photonics-assisted record-high 100/200 Gb E real-time THz wireless transmission at 360–430 GHz band, the capacity of which is 10–20 times higher than that of *** proposed fiber-THz-fiber architecture can realize the smooth conversion between high-speed THz and lightwave signals. Moreover, the architecture can significantly reduce the research difficulty and development cost, thereby considerably accelerating the commercialization of 6G THz technology by thoroughly reusing commercial digital coherent optical module(DCO) modules, which are compatible with the physical layer transmission protocols, such as IEEE 802.3 and ITU-T G.798. Finally, this study also introduces some potential directions of

关键词： 6G THz wireless communication optical fiber communication seamlessly converged architecture real-time communication

Optical-terahertz-optical seamless integration system for dual-λ 400 GbE real-time transmission at 290 GHz and 340 GHz

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Science China(Information Sciences) 2023年第11期66卷 302-304页

作者： Jiao ZHANG Mingzheng LEI Min ZHU Bingchang HUA yuancheng cai Yucong ZOU Liang TIAN Yunwu WANG Jinbiao XIAO Yongming HUANG Jianjun YU Xiaohu YOU Purple Mountain Laboratories National Mobile Communications Research Laboratory Southeast University School of Information Science and Technology Fudan University Peng Cheng Laboratory

Terahertz band(THz-band, 0.3 to 10 THz) communications are envisioned as a promising candidate for 6G and beyond technology, which can provide data capacity tens or even hundreds of Gbps per physical layer link [1–3]. Over the past several years, a series of THz communication systems at record-high data rates have undergone significant development, accelerated by electronic and hybrid electronicphotonic techniques [4–9].

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Application of Kramers–Kronig receiver in SSB-OFDM-RoF link

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Chinese Optics Letters 2019年第1期17卷 30-34页

作者： yuancheng cai Yun Ling Xiang Gao Bo Xu Kun Qiu Key Laboratory of Optical Fiber Sensing and Communications Ministry of Education University of Electronic Science and Technology of China

We propose and investigate the use of a Kramers–Kronig(KK) receiver in a single sideband orthogonal frequency division multiplexing radio over fiber(SSB-OFDM-RoF) link based on an optical remote heterodyne solution. This scheme is effective in eliminating the signal-to-signal beating interference introduced by square-law detection of a photo-detector in an SSB-OFDM-RoF link. We extensively study the influences of different carrier-to-signal power ratios(CSPRs), laser linewidths, and transmission distances on our proposed scheme. It is proved that the KK-based receiver can reduce optimal CSPR by more than 5 dB and provide about 1.1 dB gain over the conventional mixer-based receiver scheme with CSPR of 11 dB after 75 km fiber transmission.

关键词： Kronig receiver SSB-OFDM-RoF link Application of Kramers

Photonics-assisted THz wireless transmission with air interface user rate of 1-Tbps at 330–500 GHz band

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Science China(Information Sciences) 2023年第9期66卷 305-306页

作者： Min ZHU Jiao ZHANG Xiang LIU Bingchang HUA yuancheng cai Junjie DING Mingzheng LEI Yucong ZOU Liang TIAN Yunwu WANG Weidong TONG Jinbiao XIAO Yongming HUANG Jianjun YU Xiaohu YOU Purple Mountain Laboratories National Mobile Communications Research Laboratory Southeast University School of Information Science and Technology Fudan University Peng Cheng Laboratory

Air interface user rate(AIUR) of 1-Tbps is one of the most important key performance indicators(KPIs) for the future6G extreme connectivity [1]. Terahertz(THz, 300 GHz–10 THz) is recognized as a promising candidate technology in achieving the KPI towards Tbps. In the past few years, a series of THz wireless transmissions at recordhigh data rates including both the pure-electronic and photonics-assisted solutions have been demonstrated [2].

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直接探测系统中两种单边带光信号调制与恢复方法的研究

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光学学报 2019年第9期39卷 47-55页

作者：高翔蔡沅成许渤邱昆电子科技大学信息与通信工程学院光纤传感与通信教育部重点实验室

从理论上阐释了基于独立双驱动马赫-曾德尔调制器(DDMZM)和同相正交调制器的两种单边带光信号调制原理。通过研究100 Gbit/s速率75 km标准单模光纤传输系统中的16-正交幅度调制单边带信号,分析了两种方法的参数调优原理。接收端使用Kram... 详细信息

从理论上阐释了基于独立双驱动马赫-曾德尔调制器(DDMZM)和同相正交调制器的两种单边带光信号调制原理。通过研究100 Gbit/s速率75 km标准单模光纤传输系统中的16-正交幅度调制单边带信号,分析了两种方法的参数调优原理。接收端使用Kramers-Kronig(KK)算法恢复单边带信号并消除信号与信号间的拍频串扰。结果表明,由于调制器的非线性以及单边带信号的载波信号功率比的影响,在误比特率为3.8×10-3的7%硬判决前向纠错门限上,使用基于KK算法的接收机的虚载波方法与DDMZM方法相比,能够降低接收光功率约2.3 dB。

关键词：光通信调制探测光电探测器

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实施生态家园富民计划加快治理水土流失步伐

亚热带水土保持 2005年第1期17卷 1-5页

作者：蔡元呈福建省农业厅 350003

本文阐述了长汀县治理水土流失牵住封禁“牛鼻子”,以解决群众生活用能为重点,必须探索一条发展农户经济、自我解决燃料与奔小康之路;介绍了福建省实施生态家园富民计划工程的几种模式及其效益,建议长汀县结合区位特点,将实施生态家园... 详细信息

本文阐述了长汀县治理水土流失牵住封禁“牛鼻子”,以解决群众生活用能为重点,必须探索一条发展农户经济、自我解决燃料与奔小康之路;介绍了福建省实施生态家园富民计划工程的几种模式及其效益,建议长汀县结合区位特点,将实施生态家园富民计划工程作为治理水土流失的有效措施与可持续发展模式。

关键词：生态家园富民计划水土流失长汀县可持续发展模式农业生态学生态经济环境

基于Elman神经网络的烟煤与生物质混烧灰熔点预测

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中南大学学报（自然科学版） 2016年第12期47卷 4240-4247页

作者：蒋绍坚付国富黄靓云唐远程蔡攀彭好义中南大学能源科学与工程学院湖南长沙410083

基于实验法测定烟煤与不同生物质混烧灰熔点时存在工作量大、时效性差的问题,通过分析烟煤分别与玉米秸秆和木屑混烧灰的成分,并以灰成分为输入量,建立基于Elman神经网络的灰熔点预测模型。采用Levenberg-Marquardt反向传播算法训练模型... 详细信息

基于实验法测定烟煤与不同生物质混烧灰熔点时存在工作量大、时效性差的问题,通过分析烟煤分别与玉米秸秆和木屑混烧灰的成分,并以灰成分为输入量,建立基于Elman神经网络的灰熔点预测模型。采用Levenberg-Marquardt反向传播算法训练模型,利用残差检验与后验差检验法检验模型预测性能。研究结果表明:玉米秸秆灰、木屑灰分别含有较高的K_2O和CaO,与烟煤灰相比,2种生物质灰的碱性氧化物(Na_2O,K_2O,CaO,MgO)质量分数较高,酸性氧化物(Al_2O_3和SiO_2)质量分数较低;检验结果验证了该模型具有较高的预测精度和较强的泛化能力。

关键词： Elman神经网络烟煤生物质灰熔点预测模型