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破碎岩体隧道塌方预测及台阶工法调整技术研究

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人民长江 2017年第11期48卷 72-76页

作者：杨志刚肖伯强杨钊陈培帅田洪铭中交第二航务工程局有限公司湖北武汉430040 长安大学公路学院陕西西安710064 中国科学院武汉岩土力学研究所湖北武汉430071

塌方是破碎岩体隧道较易发生的工程事故,主要发生在掌子面和未支护段,塌方预测及工法适时调整是避免事故发生的有效途径。依托某塌方隧道工程,提出塌方预测及台阶工法调整流程:首先对未支护段进行塌方预测,采用拱顶岩体稳定理论评估上... 详细信息

塌方是破碎岩体隧道较易发生的工程事故,主要发生在掌子面和未支护段,塌方预测及工法适时调整是避免事故发生的有效途径。依托某塌方隧道工程,提出塌方预测及台阶工法调整流程:首先对未支护段进行塌方预测,采用拱顶岩体稳定理论评估上台阶高度,确定极限矢跨比,并采用数值计算进行验证,选择合理的台阶数目;其次对掌子面稳定性进行评估,基于地质素描对掌子面稳定性进行塌方初判,采用数值计算对掌子面稳定性进行二次评估。鉴于核心土对掌子面稳定的重要作用,对台阶施工预留核心土工法的必要性也进行了分析。最终提出了基于拱顶岩体稳定理论的塌方预测和上台阶极限矢跨比计算方法,以及基于地质素描与数值计算的掌子面稳定性分析方法,相关研究思路可为类似工程提供借鉴和参考。

关键词：塌方预测预留核心土三台阶工法隧道开挖

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沼气热源用于仔猪舍自动控温系统设计

中国农机化学报 2014年第1期35卷 255-259页

作者：蒋宏婉张富贵熊小龙田洪明陈量吕敬堂贵州大学机械工程学院贵州贵阳550025 贵州省农村能源管理站贵州贵阳550001 贵州喀斯特山乡牛业有限公司贵州镇远557700

贵州多数地区冬季天气阴冷潮湿,抵抗力较差的仔猪容易生病,而多数养殖场都有较为丰富的沼气资源,因此将沼气燃烧后转换为热能为仔猪舍加温成为养殖场循环利用热能的新途径之一。本文根据沼气供热系统特点和仔猪舍保温要求,对仔猪舍加温... 详细信息

贵州多数地区冬季天气阴冷潮湿,抵抗力较差的仔猪容易生病,而多数养殖场都有较为丰富的沼气资源,因此将沼气燃烧后转换为热能为仔猪舍加温成为养殖场循环利用热能的新途径之一。本文根据沼气供热系统特点和仔猪舍保温要求,对仔猪舍加温自动控温系统的硬件、软件进行了设计。硬件以单片机为控制核心,采用DS18B20为测温元件,以电控水泵为控制对象构成完整温控系统。软件采用C语言编程,测温精度为0.5℃。经过系统仿真分析后得知,该控制系统的响应速度快,完全可以满足仔猪舍自动控温要求。

关键词：沼气热水锅炉温度控制系统软件仿真

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多点热红外温度测量系统设计

电视技术 2019年第4期43卷 91-93,108页

作者：傅宇冯桂兰田洪铭胡晨辉中国计量大学光学与电子科技学院

对温度进行精密的监控和调节是工业生产中的一个重要环节。在无纺布生产车间中,针对布料烘干过程中温度的监控,开发了一种以STM32为核心的多点热红外温度测量系统。系统实现了热红外辐射测温、U盘温度数据存储、WiFi数据传输等功能的设... 详细信息

对温度进行精密的监控和调节是工业生产中的一个重要环节。在无纺布生产车间中,针对布料烘干过程中温度的监控,开发了一种以STM32为核心的多点热红外温度测量系统。系统实现了热红外辐射测温、U盘温度数据存储、WiFi数据传输等功能的设计,实现对移动的无纺布温度监测。实验结果表明本多点热红外温度测量系统可以实时采集多点温度数据,测量精度可以达到1℃,满足系统指标要求。

关键词：温度测量 STM32 U盘存储 WiFi发送

Performance analysis of a low-complexity nonorthogonal multiple access scheme in visible light communication downlinks using pulse modulations

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Intelligent and Converged Networks 2021年第1期2卷 50-65页

作者： Jian Song tian Cao hongming Zhang Beijing National Research Center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Digital TV System of Guangdong Province and Shenzhen City Research Institute of Tsinghua University in ShenzhenShenzhen 518057China Beijing National Research Center for Information Science and Technology(BNRist) and Department of Electronic EngineeringTsinghua UniversityBeijing 100084China

Although Successive Interference Cancellation(SIC)decoding is widely adopted in Nonorthogonal Multiple Access(NOMA)schemes for the recovery of user data at acceptable complexity,the imperfect SIC would cause Error Propagation(EP),which can severely degrade system *** this work,we propose an SIC-free NOMA scheme in pulse modulation based Visible Light Communication(VLC)downlinks,including two types of users with different data rate *** bit-rate users adopt on-off keying,whereas high bit-rate ones use Multiple Pulse Position Modulation(MPPM).The soft decision decoding scheme is exploited by high bit-rate users to decode MPPM signals,which could fundamentally eliminate the detrimental effect of EP;the scheme is also easier and faster to execute compared with the conventional SIC decoding *** of the symbol error rate and achievable data rate for two types of users are *** of the Monte Carlo simulation are provided to confirm the correctness of theoretical results.

关键词： visible light communication nonorthogonal multiple access error propagation on-off keying multiple pulse position modulation symbol error rate achievable data rate

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不同基肥对大棚黄瓜生长及产量的影响

长江蔬菜 2013年第20期 57-60页

作者：徐彦军赵小平夏先林田洪明张冬贵州大学贵阳550025 贵州省织金县科技办贵州喀斯特山乡牛业有限公司

以黄瓜品种中农8号为材料,研究不同基肥对大棚桶栽黄瓜生长、产量的影响。结果表明,处理4(CK,以硫酸钾型复合肥作为基肥)黄瓜植株生长情况良好,成株期结瓜数、单瓜鲜质量和产量都最高,分别为5个、387 g和77.4 kg/40株;处理2(以农家肥作... 详细信息

以黄瓜品种中农8号为材料,研究不同基肥对大棚桶栽黄瓜生长、产量的影响。结果表明,处理4(CK,以硫酸钾型复合肥作为基肥)黄瓜植株生长情况良好,成株期结瓜数、单瓜鲜质量和产量都最高,分别为5个、387 g和77.4 kg/40株;处理2(以农家肥作为基肥)黄瓜生长、产量表现也较好,且处理4与处理2的产量无显著性差异,即以农家肥作为当地棚栽黄瓜基肥也较适宜;以烟草育苗专用肥作为基肥对黄瓜幼苗期根系生长有积极的作用,但成株期黄瓜产量较低,不宜作为棚栽黄瓜基肥。

关键词：黄瓜基肥生长产量

A distributed approach for lidar-based relative state estimation of multi-UAV in GPS-denied environments

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Chinese Journal of Aeronautics 2022年第1期35卷 59-69页

作者： hongming SHEN Qun ZONG Hanchen LU Xuewei ZHANG Bailing tian Lei HE School of Electrical and Information Engineering Ticmjin UniversityTianjin 300072China Institute of Field Engineering Army Engineering University of PLANanjing 210007China

In this paper,we present a distributed framework for the lidar-based relative state estimator which achieves highly accurate,real-time trajectory estimation of multiple Unmanned Aerial Vehicles(UAVs)in GPS-denied *** system builds atop a factor graph,and only on-board sensors and computing power are *** from the keyframe strategy,each UAV performs relative state estimation individually and broadcasts very partial information without exchanging raw *** complete system runs in real-time and is evaluated with three experiments in different *** results show that the proposed distributed approach offers comparable performance with a centralized method in terms of accuracy and real-time *** flight test demonstrates that the proposed relative state estimation framework is able to be used for aggressive flights over 5 m/s.

关键词： Distributed relative state estimation GPS-denied environments Lidar-based perception Multi-UAV system Pose-graph optimization

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沼气能源对仔猪舍的增温效果分析

中国农机化学报 2016年第7期37卷 213-216页

作者：袁奎张富贵熊小龙田洪明梁恩东贵州大学机械工程学院贵阳市550025 贵州省农村能源管理站贵阳市550001 贵州喀斯特山乡牛业有限公司贵州镇远557700

仔猪对猪舍环境温度要求较高,只有在较适宜的温度条件下,才能充分发挥仔猪的生产潜能。通过研究影响仔猪舍温度变化的因素,对仔猪舍进行沼气增温和添加墙体保温材料保温处理,地面温度值保持在30℃以上,空间温度值保持在25℃左右,热水管... 详细信息

仔猪对猪舍环境温度要求较高,只有在较适宜的温度条件下,才能充分发挥仔猪的生产潜能。通过研究影响仔猪舍温度变化的因素,对仔猪舍进行沼气增温和添加墙体保温材料保温处理,地面温度值保持在30℃以上,空间温度值保持在25℃左右,热水管壁温度基本稳定在65℃左右,使仔猪舍的环境温度保持在适宜的状态。为仔猪营造一个适宜其生长发育的优良环境,达到充分发挥仔猪的生产潜能和合理利用能源的目的。

关键词：仔猪环境温度增温沼气能源

Recent advances in multifunctional electrochromic energy storage devices and photoelectrochromic devices

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Science China Chemistry 2017年第1期60卷 13-37页

作者： Zhongqiu Tong Yanlong tian hongming Zhang Xingang Li Junyi Ji Huiying Qu Na Li Jiupeng Zhao Yao Li College of Materials and Metallurgical Engineering Guizhou Institute of Technology Guiyang 550003 China Center for Composite Materials and Structure Harbin Institute of Technology Harbin 150001 China School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150001 China Guizhou Construction Science Research & Design Institute Limited Company of China State construction Engineering Corporation Guiyang 550006 China

Multifunctional devices integrated with electrochromism and energy storage or energy production functions are attractive because these devices can be used as an effective approach to address the energy crisis and environmental pollution in society today. In this review, we explain the operation principles of electrochromic energy storage devices including electrochromic supercapacitors,electrochromic batteries, and the photoelectrochromic devices. Furthermore, the material candidates and structure types of these multifunctional devices are discussed in detail. The major challenges of these devices along with a further outlook are highlighted at the end.

关键词： electrochromic multifunctional devices electrochromic supercapacitors electrochromic batteries photoelectrochromic devices

A Parallel Mapping and Planning Strategy for Micro Aerial Vehicle

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Guidance, Navigation and Control 2022年第2期2卷 125-145页

作者： Zhuo Wang Qun Zong hongming Shen Bailing tian Hanchen Lu School of Electrical and Information Engineering Tianjin UniversityTianjin 300072P.R.China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing Electro-Mechanical Engineering Institute Beijing 100083P.R.China

Autonomous fight is a fundamental problem for various saplications of miaro aerial vehicles(MAVs).Thanks to the dewvelopment of *** and Control(GNC)techndogle,the rsearch on this problem i abo becoming ***,safe fight in unknown,dut tered enviouments remains an open question,epeaially with real-time reguirement on onboard *** paper propoes a framnework including prlelly mapping and planning and implements it on Graphics Pmocessing Unit(GPU).First,a spherical coomlinate proijection is used in the ocupency grid map to avold menory *** that,in the planning phase,a method baed on latice state space sampling is applied to obtain mutiple rajectorfe ***,we design a series of aoft constraints to ensure that the MAV is in a safe known space with optimal *** solving the cost for each trajectory and comparison,the optimal trajectory can be *** efectivenes of the propeed strategy is demonstrated through simulation testa.

关键词： Motion planning lattice planner parallel processing