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Impact of Sky Conditions on Net Ecosystem Productivity over a “Floating Blanket” Wetland in Southwest China

Advances in Atmospheric Sciences 2024年第2期41卷 355-368页

作者： Yamei SHAO Huizhi liU Qun DU Yang liU Jihua SUN yaohui li Jinlian li State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100029China Yunnan Meteorological Observatory Kunming 530100China College of Aviation Meteorology Civil Aviation Flight University of ChinaGuanghan 618307China Meteorological Bureau of Tengchong County Baoshan 679100China

Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were divided into overcast, cloudy, and sunny conditions. On the half-hourly timescale, the daytime NEP responded more rapidly to the changes in the total photosynthetic active radiation(PARt) under overcast and cloudy skies than that under sunny skies. The increase in the apparent quantum yield under overcast and cloudy conditions was the greatest in spring and the least in summer. Additionally, lower atmospheric vapor pressure deficit(VPD) and moderate air temperature were more conducive to enhancing the apparent quantum yield under cloudy skies. On the daily timescale, NEP and the gross primary production(GPP) were higher under cloudy or sunny conditions than those under overcast conditions across seasons. The daily NEP and GPP during the wet season peaked under cloudy skies. The daily ecosystem light use efficiency(LUE) and water use efficiency(WUE) during the wet season also changed with sky conditions and reached their maximum under overcast and cloudy skies, respectively. The diffuse photosynthetic active radiation(PAR_d) and air temperature were primarily responsible for the variation of daily NEP from half-hourly to monthly timescales, and the direct photosynthetic active radiation(PAR_b) had a secondary effect on NEP. Under sunny conditions, PAR_b and air temperature were the dominant factors controlling daily NEP. While daily NEP was mainly controlled by PAR_d under cloudy and overcast conditions.

关键词： diffuse radiation eddy covariance NEP controlling factors wetland path analysis

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Masculinizer gene controls sexual differentiation in Hyphantria cunea

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Insect Science 2024年第2期31卷 405-416页

作者： Xiaowei li Huihui liu Honglun Bi yaohui Wang Jun Xu Sufang Zhang Zhen Zhang Ze Zhang Yongping Huang Laboratory of Evolutionary and Functional Genomics School of Life SciencesChongqing UniversityChongqingChina CAS Key Laboratory of Insect Developmental and Evolutionary Biology CAS Centerfor Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghaiChina Key Laboratory of Forest Protection Research Institute of Forest EcologyEnvironment and ProtectionChinese Academy of ForestryState Forestry AdministrationBeijingChina

The Masculinizer gene,Masc,encodes a lepidopteran-specific novel CCCHtype zinc finger protein,which controls sex determination and dosage compensation in Bombyx mori.Considering the potential application of it in pest control,it is necessary to investigate the function of Masc gene in Hyphantria cunea,a globally invasive forest pest.In the present study,we identified and functionally characterized the Masc gene,HcMasc,in H.cunea.Sequence analysis revealed that HcMASC contained the conserved CCCH-type zinc finger domain,nuclear localization signal,and male determining domain,in which the last was confirmed to be required for its masculinization in BmN cell line.However,expression data showed that unlike male-biased expression in B.mori,Hc-Masc gene expresses in main all developmental stages or tissues in both sexes.Clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9-based disruption of the common exons 1 and 3 of the HcMasc gene resulted in imbalanced sex ratio and abnormal external genitalia of both sexes.Our results suggest that the HcMasc gene is required for both male and female sexual differentiation and dosage compensation in H.cunea and provide a foundation for developing better strategies to control this pest.

关键词： CRISPR/Cas9 dosage compensation Hyphantria cunea Masc sexual differentiation

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Sparse spatial transformers for few-shot learning

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Science China(Information Sciences) 2023年第11期66卷 23-34页

作者： Haoxing CHEN Huaxiong li yaohui li Chunlin CHEN Department of Control Science and Intelligence Engineering Nanjing University

Learning from limited data is challenging because data scarcity leads to a poor generalization of the trained model. A classical global pooled representation will probably lose useful local information.Many few-shot learning methods have recently addressed this challenge using deep descriptors and learning a pixel-level metric. However, using deep descriptors as feature representations may lose image contextual information. Moreover, most of these methods independently address each class in the support set, which cannot sufficiently use discriminative information and task-specific embeddings. In this paper, we propose a novel transformer-based neural network architecture called sparse spatial transformers(SSFormers), which finds task-relevant features and suppresses task-irrelevant features. Particularly, we first divide each input image into several image patches of different sizes to obtain dense local features. These features retain contextual information while expressing local information. Then, a sparse spatial transformer layer is proposed to find spatial correspondence between the query image and the full support set to select task-relevant image patches and suppress task-irrelevant image patches. Finally, we propose using an image patch-matching module to calculate the distance between dense local representations, thus determining which category the query image belongs to in the support set. Extensive experiments on popular few-shot learning benchmarks demonstrate the superiority of our method over state-of-the-art methods.

关键词： few-shot Learning transformer metric-learning cross-attention

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Relationships between Cloud Droplet Spectral Relative Dispersion and Entrainment Rate and Their Impacting Factors

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Advances in Atmospheric Sciences 2022年第12期39卷 2087-2106,I0016-I0019页

作者： Shi LUO Chunsong LU Yangang liU yaohui li Wenhua GAO Yujun QIU Xiaoqi XU Junjun li Lei ZHU Yuan WANG Junjie WU Xinlin YANG College of Aviation Meteorology Civil Aviation Flight University of ChinaGuanghan 618307China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science&TechnologyNanjing 210044China Environmental and Climate Sciences Department Brookhaven National LaboratoryUptonNew York 11973US State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Nanjing Joint Institute for Atmospheric Sciences Nanjing 210019China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China

Cloud microphysical properties are significantly affected by entrainment and mixing processes.However,it is unclear how the entrainment rate affects the relative dispersion of cloud droplet size distribution.Previously,the relationship between relative dispersion and entrainment rate was found to be positive or negative.To reconcile the contrasting relationships,the Explicit Mixing Parcel Model is used to determine the underlying mechanisms.When evaporation is dominated by small droplets,and the entrained environmental air is further saturated during mixing,the relationship is negative.However,when the evaporation of big droplets is dominant,the relationship is positive.Whether or not the cloud condensation nuclei are considered in the entrained environmental air is a key factor as condensation on the entrained condensation nuclei is the main source of small droplets.However,if cloud condensation nuclei are not entrained,the relationship is positive.If cloud condensation nuclei are entrained,the relationship is dependent on many other factors.High values of vertical velocity,relative humidity of environmental air,and liquid water content,and low values of droplet number concentration,are more likely to cause the negative relationship since new saturation is easier to achieve by evaporation of small droplets.Further,the signs of the relationship are not strongly affected by the turbulence dissipation rate,but the higher dissipation rate causes the positive relationship to be more significant for a larger entrainment rate.A conceptual model is proposed to reconcile the contrasting relationships.This work enhances the understanding of relative dispersion and lays a foundation for the quantification of entrainment-mixing mechanisms.

关键词： clouds entrainment rate relative dispersion of cloud droplet size distribution mixing and evaporation

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Attribution of the Tibetan Plateau to northern drought

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National Science Review 2020年第3期7卷 489-492页

作者： Yuzhi liu yaohui li Jianping Huang Qingzhe Zhu Shanshan Wang Key Laboratory for Semi-Arid Climate Change of the Ministry of Education Lanzhou University Institute of Arid Meteorology China Meteorology Administration

The Tibetan Plateau (TP), which is located in Asia and has an average elevation of over 4000 m, acts as a raised source of heat [1] and an isolated region of humidity in the atmosphere [2]. The TP serves as a ‘world ... 详细信息

关键词： Attribution of the Tibetan Plateau to northern drought

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浅埋深黄泥顶板工作面围岩稳定性控制

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晋控科学技术 2024年第1期 5-10页

作者：李耀晖晋能控股集团晋城公司七一煤矿山西晋城048406

为有效治理晋能控股集团晋城公司七一煤矿9114综采工作面回采期间出现的大面积黄泥冒顶,通过理论分析、微观结构测试和现场实践,揭示了浅埋深黄泥顶板工作面的围岩失稳原因,并提出“留底割顶+短支短护+支架少降快移”的直接顶稳定性控... 详细信息

为有效治理晋能控股集团晋城公司七一煤矿9114综采工作面回采期间出现的大面积黄泥冒顶,通过理论分析、微观结构测试和现场实践,揭示了浅埋深黄泥顶板工作面的围岩失稳原因,并提出“留底割顶+短支短护+支架少降快移”的直接顶稳定性控制技术。现场应用表明,该技术有效控制了9114工作面黄泥冒顶事故,顶底板移近量稳定在可控范围内,保证了工作面正常回采,为类似条件下工作面围岩稳定性控制提供一定参考。

关键词：浅埋煤层黄泥顶板短支短护围岩稳定性

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基于模糊控制的光子辐射制冷功率测量系统

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光学学报 2024年第2期44卷 170-179页

作者：周玉晟朱虹雨陈犇陈嘉诚詹耀辉李孝峰苏州大学光电科学与工程学院江苏苏州215006 江苏省先进光学制造技术重点实验室教育部现代光学技术重点实验室江苏苏州215006

依据热平衡原理设计了以单片机为控制核心,DS18B20数字温度传感器和铂电阻PT100为检温元件,正温度系数(PTC)效应加热器为执行元件的温控及制冷功率测量系统。通过模糊PID(Proportional Integral Derivative)控制算法输出不同占空比的脉... 详细信息

依据热平衡原理设计了以单片机为控制核心,DS18B20数字温度传感器和铂电阻PT100为检温元件,正温度系数(PTC)效应加热器为执行元件的温控及制冷功率测量系统。通过模糊PID(Proportional Integral Derivative)控制算法输出不同占空比的脉宽调制波,控制辐射冷却材料温度和环境温度保持一致性,同时利用3D打印工艺完成装置的搭建,最终测算出辐射制冷功率。实验结果表明,系统测量计算的辐射制冷功率与理论预测值接近,该系统可以有效满足多种辐射冷却材料的测量。

关键词：测量辐射制冷制冷功率单片机温度调控模糊PID

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基于生成神经网络的自适应热控薄膜设计

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光学学报 2024年第7期44卷 261-270页

作者：陈嘉诚马蔚朱虹雨周玉晟詹耀辉李孝峰苏州大学光电科学与工程学院江苏苏州215006 江苏省先进光学制造技术重点实验室暨教育部现代光学技术重点实验室江苏苏州215006 浙江大学信息与电子工程学院浙江杭州310027

自适应温度调控器件以其智能开关特性而逐渐成为研究焦点,但是一方面其特殊的光谱要求使得器件设计过程复杂且周期冗长,另一方面器件热控性能亟待提高以满足更加严苛的应用场景。针对以上问题,提出一种深度生成神经网络模型来执行上述... 详细信息

自适应温度调控器件以其智能开关特性而逐渐成为研究焦点,但是一方面其特殊的光谱要求使得器件设计过程复杂且周期冗长,另一方面器件热控性能亟待提高以满足更加严苛的应用场景。针对以上问题,提出一种深度生成神经网络模型来执行上述复杂的优化任务,该网络模型的更新不依赖于数据集,而是将生成神经网络与传输矩阵方法(TMM)相结合,通过TMM返回的梯度信息指导产生符合预期的多层膜结构,并自动优化膜层厚度和材料种类。作为网络优化能力的验证和演示,本课题组使用该方法设计了一种基于二氧化钒的自适应热控器件,实现了高温太阳吸收比低于0.2、高温发射率高于0.9、发射率差值大于0.8的优异性能。与传统的优化算法相比,生成神经网络以高自由度和更快的速度寻找最优解,与普通神经网络相比,全局优化网络考虑整体的优化目标,通过全局搜索寻找全局最优解,设计结果也证明了该方法在复杂设计任务中的实用性。

关键词：薄膜多层膜神经网络自适应温度调控二氧化钒

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冻融作用下冰碛体剪切特性与围岩压力研究

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地下空间与工程学报 2024年第2期20卷 460-470页

作者：陈志敏刘耀辉李宁兰州交通大学土木工程学院兰州730070 中国市政工程西北设计研究院有限公司兰州730030 中铁第一勘察设计院集团有限公司西安710043

冰碛体是由冰川作用搬运大量碎屑物质堆积形成的特殊岩土体。受赋存的地理及气候条件影响,冻融作用会对穿越该类围岩的隧道尤其是洞口段的工程建设带来挑战。笔者调研了中国西藏地区冰碛体围岩地质条件,设置冻融循环直剪试验研究了冻融... 详细信息

冰碛体是由冰川作用搬运大量碎屑物质堆积形成的特殊岩土体。受赋存的地理及气候条件影响,冻融作用会对穿越该类围岩的隧道尤其是洞口段的工程建设带来挑战。笔者调研了中国西藏地区冰碛体围岩地质条件,设置冻融循环直剪试验研究了冻融循环次数与含水率对冻结冰碛体的力学特性和力学指标影响,引入冻融次数与含水率综合参数K,拟合得出黏聚力c公式。结果表明:冻融循环和含水率对冰碛体黏聚力c有较大影响。改进了太沙基理论,提出了适用于冰碛体围岩隧道洞口段的围岩压力计算公式。以昌林铁路某隧道为例,计算不同条件下的围岩压力,验证了公式的合理性。研究发现:冻融循环和含水率是影响冰碛体力学性能变化的重要因素,冻融作用对洞口段隧道围岩压力有不同程度的影响,在工程建设中应充分考虑。

关键词：冰碛体冻融循环直剪试验围岩压力

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Effects of Updated RegCM4 Land Use Data on Near-Surface Temperature Simulation in China

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Journal of Meteorological Research 2018年第5期32卷 758-767页

作者： Yulong REN yaohui li Zhaoxia PU Tiejun ZHANG Haixia DUAN Wei WANG Institute of Arid Meteorology of China Meteorological Administration(CMA) Key Laboratory of Arid Climatic Change and Disaster Reduction of Gansu Province and CMALanzhou 730020China Department of Atmospheric Sciences University of UtahUtah 84112USA

Biogeophysical effects of land use and land cover （LULC） changes play a significant role in modulating climate on various spatial scales. In this study, a set of recent LULC products with a spatial resolution of 500 m was developed in China for update in RegCM4 （regional climate model version 4）. Two sets of comparative numerical experiments were conducted to study the effects of LULC changes on near-surface temperature simulation. The results show that after LULC changes, areas of crops and mixed woodlands as well as urban areas increase over entire China, accom- panied with greatly expanded mixed farming and forests/field mosaics in southern China, and reduced areas of 1） ir- rigated crops and short grasses in northern China and the Tibetan Plateau, and 2） semi-desert and desert in northwest-em China. Improvements in the LULC data clearly result in more accurate simulations of the near-surface temperat-ure. Specifically, increasing latent heat and longwave albedo due to enhanced LULC in certain areas lead to reduc-tion in land surface temperature （LST）, while changes in shortwave albedo and sensible heat also exert a great influ- ence on the LST. Overall, these parameter adjustments reduce the biases in near-surface temperature simulation.

关键词： land use and land cover RegCM4 （regional climate model version 4） temperature simulation

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