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移动场景下高速可见光通信系统硬件电路设计

实验技术与管理 2024年第1期41卷 91-99页

作者：李宗艳何凌燕孙俊倡张冠杰马帅方俊彬李世银中国矿业大学信息与控制工程学院江苏徐州221116 鹏城实验室广东深圳518055 暨南大学光电工程系广东广州510632

针对移动场景下高速可见光通信中存在信号衰减快与系统带宽受限问题,创新设计了能够实现高速、稳定可见光通信系统的自适应均衡硬件电路。首先,从自适应控制接收信号衰减角度,提出一种面向移动可见光通信的自适应增益电路设计方案。其次... 详细信息

针对移动场景下高速可见光通信中存在信号衰减快与系统带宽受限问题,创新设计了能够实现高速、稳定可见光通信系统的自适应均衡硬件电路。首先,从自适应控制接收信号衰减角度,提出一种面向移动可见光通信的自适应增益电路设计方案。其次,从补偿通信系统频响衰减角度,设计了一种模拟预均衡与后均衡电路。最后,基于所设计的电路搭建了可见光通信硬件测试平台。实验结果表明,将自适应均衡电路应用于可见光通信系统中,可以有效提高通信速率,还可有效克服移动过程中信号衰减与中断问题。

关键词：可见光通信均衡电路自适应放大电路以太网通信

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An Underwater Target Detection Algorithm Based on Attention Mechanism and Improved YOLOv7

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Computers, Materials & Continua 2024年第2期78卷 2829-2845页

作者： Liqiu Ren Zhanying Li Xueyu he lingyan Kong Yinghao Zhang College of Information Science and Engineering Dalian Polytechnic UniversityDalian116034China

For underwater robots in the process of performing target detection tasks,the color distortion and the uneven quality of underwater images lead to great difficulties in the feature extraction process of the model,which is prone to issues like error detection,omission detection,and poor ***,this paper proposed the CER-YOLOv7(CBAM-EIOU-RepVGG-YOLOv7)underwater target detection *** improve the algorithm’s capability to retain valid features from both spatial and channel perspectives during the feature extraction phase,we have added a Convolutional Block Attention Module(CBAM)to the backbone *** Reparameterization Visual Geometry Group(RepVGG)module is inserted into the backbone to improve the training and inference *** Efficient Intersection over Union(EIoU)loss is also used as the localization loss function,which reduces the error detection rate and missed detection rate of the *** experimental results of the CER-YOLOv7 algorithm on the UPRC(Underwater Robot Prototype Competition)dataset show that the mAP(mean Average Precision)score of the algorithm is 86.1%,which is a 2.2%improvement compared to the *** feasibility and validity of the CER-YOLOv7 are proved through ablation and comparison experiments,and it is more suitable for underwater target detection.

关键词： Deep learning underwater object detection improved YOLOv7 attention mechanism

Gibberellin promotes cambium reestablishment during secondary vascular tissue regeneration after girdling in an auxin-dependent manner in Populus

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Journal of Integrative Plant Biology 2024年第1期66卷 86-102页

作者： Yufei Zhang lingyan Wang Yuexin Wu Donghui Wang Xin‐Qiang he State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China

Secondary vascular tissue(SVT)development and regeneration are regulated by *** this study,we used an in vitro SVT regeneration system to demonstrate that gibberellin(GA)treatment significantly promotes auxin-induced cambium *** GA content by overexpressing or knocking down ent-kaurene synthase(KS)affected secondary growth and SVT regeneration in *** poplar DELLA gene GIBBERELLIC ACID INSENSITIVE(PtoGAI)is expressed in a specific pattern during secondary growth and cambium regeneration after *** of PtoGAI disrupted poplar growth and inhibited cambium regeneration,and the inhibition of cambium regeneration could be partially restored by GA *** analysis of the PtaDR5:GUS transgenic plants,the localization of PIN-FORMED 1(PIN1)and the expression of auxin-related genes found that an additional GA treatment could enhance the auxin response as well as the expression of PIN1,which mediates auxin transport during SVT *** together,these findings suggest that GA promotes cambium regeneration by stimulating auxin signal transduction.

关键词： auxin cambium gibberellin Populus secondary vascular tissue regeneration

Secondary organic aerosol formation from straw burning using an oxidation flow reactor

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Journal of Environmental Sciences 2022年第4期34卷 249-258页

作者： Hui Wang Song Guo Zhijun Wu Kai Qiao Rongzhi Tang Ying Yu Weizhao Xu Wenfei Zhu Liwu Zeng Xiaofeng Huang lingyan he Mattias Hallquist State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Laboratory for Regional Pollution ControlMinistry of Education(IJRC)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing 10044China Key Laboratory for Urban Habitat Environmental Science and Technology College of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China Department of Chemistry and Molecular Biology Atmospheric ScienceUniversity of GothenburgSE-41296 GothenburgSweden

herein,we use an oxidation flow reactor,Gothenburg:Potential Aerosol Mass(Go:PAM)reactor,to investigate the secondary organic aerosol(SOA)formation from wheat straw *** burning emissions are exposed to high concentrations of hydroxyl radicals(OH)to simulate processes equivalent to atmospheric oxidation of 0-2.55 *** volatile organic compounds(VOCs)were investigated,and particles were measured before and after the Go:PAM *** influence of water content(i.e.5%and 11%)in wheat straw was also *** burning stages,the flaming stage,and non-flaming stages,were *** particle emission factors(EFs)at a water content of 11%(~3.89 g/kg-fuel)are significantly higher than those at a water content of 5%(~2.26 g/kg-fuel)during the flaming ***,the water content showed no significant influence at the non-flaming *** of aromatics at a non-flaming stage(321.8±46.2 mg/kg-fuel)are larger than that at a flaming stage(130.9±37.1 mg/kg-fuel).The OA enhancement ratios increased with the increase in OH exposure at first and decreased with the additional increment of OH *** maximum OA enhancement ratio is~12 during the non-flaming stages,which is much higher than~1.7 during the flaming *** mass spectrum of the primary wheat burning organic aerosols closely resembles that of resolved biomass burning organic aerosols(BBOA)based on measurements in ambient *** results show that large gap(0%-90%)still remains to estimate biomass burning SOA if only the oxidation of VOCs were included.

关键词： Gothenburg:Potential Aerosol Mass(Go:PAM)reactor Wheat straw burning Flaming Non-flaming Secondary organic aerosol formation

Progress in quantitative research on the relationship between atmospheric oxidation and air quality

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Journal of Environmental Sciences 2023年第1期123卷 350-366页

作者： Yuesi Wang Xin Jin Zirui Liu Gehui Wang Guiqian Tang Keding Lu Bo Hu Shanshan Wang Guohui Li Xinqin An Chao Wang Qihou Hu lingyan he Fenfen Zhang Yuanhang Zhang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China 3 State Key Joint Laboratory or Environmental Simul ation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Key Lab of Geophysical Information System of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 201203China Key Lab of Aerosol Chemistry and Physics State Key Laboratory of Loess and Quaternary GeologyInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Institute of Atmospheric Composition and Environmental Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China Key Lab of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China

Atmospheric oxidizing capacity(AOC)is an essential driving force of troposphere chemistry and self-cleaning,but the definition of AOC and its quantitative representation remain *** by national demand for air pollution control in recent years,Chinese scholars have carried out studies on theories of atmospheric chemistry and have made considerable progress in AOC *** paper will give a brief review of these ***,AOC indexes were established that represent apparent atmospheric oxidizing ability(AOIe)and potential atmospheric oxidizing ability(AOIp)based on aspects of macrothermodynamics and microdynamics,respectively.A closed study refined the quantitative contributions of heterogeneous chemistry to AOC in Beijing,and these AOC methods were further applied in Beijing-Tianjin-hebei and key areas across the *** addition,the detection of ground or vertical profiles for atmospheric OH·,HO_(2)·,NO_(3)·radicals and reservoir molecules can now be obtained with domestic instruments in diverse ***,laboratory smoke chamber simulations revealed heterogeneous processes involving reactions of O_(3)and NO_(2),which are typical oxidants in the surface/interface atmosphere,and the evolutionary and budgetary implications of atmospheric oxidants reacting under multispecies,multiphase and multi-interface conditions were ***,based on the GRAPES-CUACE adjoint model improved by Chinese scholars,simulations of key substances affecting atmospheric oxidation and secondary organic and inorganic aerosol formation have been *** numerical simulations of AOIe and AOIp were performed,and regional coordination of AOC was *** optimized plan for controlling O_(3)and PM2.5was analyzed by scenario simulation.

关键词： Atmospheric oxidizing capacity(AOC) Quantitative index Free radicals Observation and modeling Air quality

Characterizing oxygenated volatile organic compounds and their sources in rural atmospheres in China

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Journal of Environmental Sciences 2019年第7期31卷 148-155页

作者： Yu Han Xiaofeng Huang Chuan Wang Bo Zhu lingyan he Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Oxygenated volatile organic compounds(OVOCs) are important precursors and products of atmospheric secondary pollution. The sources of OVOCs, however, are still quite uncertain,especially in the atmosphere with much pollution in China. To study the sources of OVOCs in rural atmospheres, a proton transfer reaction mass spectrometry(PTR-MS) was deployed at a northern rural site(WD) and a southern rural site(YMK) in China during the summer of 2014 and 2016, respectively. The continuous observation showed that the mean concentration of TVOCs(totally 17 VOCs) measured at WD(52.4 ppbv) was far higher than that at YMK(11.1 ppbv), and the OVOCs were the most abundant at both the two sites. The diurnal variations showed that local sources of OVOCs were still prominent at WD, while regional transport influenced YMK much. The photochemical age-based parameterization method was then used to quantitatively apportion the sources of ambient OVOCs. The anthropogenic primary sources at WD and YMK contributed less(2%–16%) to each OVOC species. At both the sites, the atmospheric background had a dominant contribution(～ 50%) to acetone and formic acid, while the anthropogenic secondary formation was the main source(～ 40%) of methanol and MEK. For acetaldehyde and acetic acid, the biogenic sources were their largest source(～ 40%) at WD, while the background(39%) and anthropogenic secondary formation(42%) were their largest sources at YMK, respectively. This study reveals the complexity of sources of OVOCs in China, which urgently needs explored further.

关键词： OVOCs Photochemical age Anthropogenic sources Primary emission Secondary formation

Source apportionment and secondary organic aerosol estimation of PM_(2.5) in an urban atmosphere in China

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Science China Earth Sciences 2014年第4期57卷 1352-1362页

作者： HUANG XiaoFeng YUN Hui GONG Zhaoheng LI Xiang he lingyan ZHANG YuanHang HU Min Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University

PM2.5 is the key pollutant in atmospheric pollution in *** new national air quality standards taking effect,PM2.5 has become a major issue for future pollution *** effectively prevent and control PM2.5,its emission sources must be precisely and thoroughly ***,there are few publications reporting comprehensive and systematic results of PM2.5 source apportionment in the *** on PM2.5 sampling during 2009 in Shenzhen and follow-up investigation,positive matrix factorization(PMF)analysis has been carried out to understand the major sources and their temporal and spatial *** results show that in urban Shenzhen(University Town site),annual mean PM2.5 concentration was 42.2μg m?3,with secondary sulfate,vehicular emission,biomass burning and secondary nitrate as major sources;these contributed30.0%,26.9%,9.8%and 9.3%to total PM2.5,*** sources included high chloride,heavy oil combustion,sea salt,dust and the metallurgical industry,with contributions between 2%–4%.Spatiotemporal variations of various sources show that vehicular emission was mainly a local source,whereas secondary sulfate and biomass burning were mostly *** nitrate had both local and regional *** of secondary organic aerosol(SOA)has always been difficult in aerosol source *** this study,the PMF model and organic carbon/elemental carbon(OC/EC)ratio method were combined to estimate SOA in *** results show that in urban Shenzhen,annual SOA mass concentration was 7.5μg m?3,accounting for 57%of total organic matter,with precursors emitted from vehicles as the major *** work can serve as a case study for further in-depth research on PM2.5 pollution and source apportionment in China.

关键词： PM2.5 source apportionment secondary organic aerosol(SOA)

Development of an on-line measurement system for water-soluble organic matter in PM_(2.5) and its application in China

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Journal of Environmental Sciences 2018年第7期30卷 33-40页

作者： Huiying Li Xiaofeng Huang Liming Cao Yuhong Zhai Liwu Zeng lingyan he Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Water-soluble organic matter（WSOM） represents a critical fraction of fine particles（PM2.5）in the air, but its changing behaviors and formation mechanisms are not well understood yet, partly due to the lack of fast techniques for the ambient measurements. In this study,a novel system for the on-line measurement of water-soluble components in PM2.5, the particle-into-liquid sampler（PILS）–Nebulizer–aerosol chemical speciation monitor（ACSM）, was developed by combining a PILS, a nebulizer, and an ACSM. High time resolution concentrations of WSOM, sulfate, nitrate, ammonium, and chloride, as well as mass spectra, can be obtained with satisfied quality control results. The system was firstly applied in China for field measurement of WSOM. The mass spectrum of WSOM was found to resemble that of oxygenated organic aerosol, and WSOM agreed well with secondary inorganic ions. All evidence collected in the field campaign demonstrated that WSOM could be a good surrogate of secondary organic aerosol（SOA）. The PILS–Nebulizer–ACSM system can thus be a useful tool for intensive study of WSOM and SOA in PM2.5.

关键词： PM2.5 Water-soluble organic matter Secondary organic matter On-line measurement Mass spectrum

Complete entanglement analysis on electron spins using quantum dot and microcavity coupled system

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Science China(Physics,Mechanics & Astronomy) 2013年第11期56卷 2054-2058页

作者： WANG Chuan he lingyan ZHANG Yong MA HaiQiang ZHANG Ru School of Science Beijing University of Posts and Telecommunications State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

We present an entanglement analysis protocol on entangled electron spins using quantum dot(QD)and microcavity coupled *** quantum dot is placed in the microcavity and ancilla photon input-output process could be used to check the parity of the quantum *** the parity check process,the user only needs to measure the spin direction of the QD spin,and the state information can be readout *** feasibility of our scheme and the experimental challenge are discussed by considering currently available techniques.

关键词： entanglement analysis quantum dot microcavity