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多源遥感图像融合语义分割发展现状与展望

现代雷达 2024年第2期46卷 16-24页

作者：何友刘瑜谭大宁张一鸣张财生孙顺丁自然姜乔文海军航空大学山东烟台264001 清华大学电子工程系北京100084

遥感图像的语义信息提取正成为城市规划利用、土地覆盖勘察、灾害变化检测以及海上态势感知等研究方向的关键技术之一。文中从由“单源”向“多源”发展的遥感图像智能处理需求出发,首先概述并分析了大数据时代和深度学习背景下的遥感... 详细信息

遥感图像的语义信息提取正成为城市规划利用、土地覆盖勘察、灾害变化检测以及海上态势感知等研究方向的关键技术之一。文中从由“单源”向“多源”发展的遥感图像智能处理需求出发,首先概述并分析了大数据时代和深度学习背景下的遥感图像语义分割发展现状,主要包括单一来源图像语义分割、多源遥感图像融合语义分割和多源(同质/异质)遥感图像变化检测。然后在阐述主要方法的基础上,提炼并总结了多源遥感图像语义分割的关键技术,主要有单源遥感图像快速语义分割语义信息辅助的多源遥感图像精确配准与融合、基于多源遥感图像的语义信息智能提取。最后,针对多源遥感图像在轨处理需求,概括出高分辨率多源遥感图像智能一体化信息提取所面临的技术挑战,并对未来发展趋势进行展望。

关键词：多源遥感图像语义分割图像融合智能处理

基于高斯混合过程的空间机器人任务空间预测控制方法

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系统工程与电子技术 2023年第11期45卷 3597-3605页

作者：柳子然戴梓健岳程斐王培基曹喜滨哈尔滨工业大学航天学院黑龙江哈尔滨150001 哈尔滨工业大学(深圳)空间科学与应用技术研究院广东深圳518055

针对空间机器人的精准操控需求和任务空间控制问题,提出了一种基于高斯混合过程的模型预测控制方法。在建立的空间机器人标称模型基础上,考虑实际工作过程中由于关节摩擦、参数测量误差导致的建模误差,利用高斯混合过程对标称模型的不... 详细信息

针对空间机器人的精准操控需求和任务空间控制问题,提出了一种基于高斯混合过程的模型预测控制方法。在建立的空间机器人标称模型基础上,考虑实际工作过程中由于关节摩擦、参数测量误差导致的建模误差,利用高斯混合过程对标称模型的不确定性进行精确、高效的分析和修正。其次,基于修正后的模型提出了非线性模型预测控制方法,在考虑实际物理约束,如关节限位、输入饱和等的情况下,实现了空间机器人基座和机械臂末端位姿对期望轨迹的直接精准跟踪。最后,考虑航天器在轨操控中的推力器冗余配置问题,设计了推力分配方案,并通过仿真结果校验了所设计控制方法的有效性。

关键词：空间机器人任务空间控制模型预测控制高斯混合过程

Rotifer community structure and assessment of water quality in Yangcheng Lake

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Chinese Journal of Oceanology and Limnology 2012年第1期30卷 47-58页

作者： CHEN Lijing liu Qiao PENG ziran HU Zhongjun XUE Junzeng WANG Wu Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources(MOE-affiliated) Shanghai Ocean UniversityShanghai 201305China Ministry of Agriculture Key Laboratory of Aquatic Genetic Resources and Aquaculture Ecology Shanghai Ocean UniversityShanghai 201306China

Rotifer community structure was investigated in Yangcheng Lake in 2008. Dominant species and species diversity indices were determined and QB/T was used to assess water quality. The annual average density and biomass of the rotifers in Yangcheng Lake was 2 894＋ 1 006 indYL and 12.47± 10.28 mg/L, respectively. The highest densities were observed in the western portion of the lake in March, but the highest biomass occurred in inflowing creeks in September. Within a year of monitoring in Yangcheng Lake, 93 species were identified and the dominant species were found to be Polyarthra trigla, Brachionus angularis, Keratella eochlearis, Keratella valga, Brachionus calyciflorus, and Filinia major. Of the species recorded, 75 were pollution indicator species. Density and biomass exhibited significant positive correlations with water temperature （R=0,209, P=0.003; R=0.446, P=0.000）, but the peak density showed two lags in response to chl a. According to the Jaccard similarity index （S0, the greatest similarity among dominant species occurred between creeks and the eastern part of the lake. The annual average Shannon-Wiener diversity index H＇, Margalef richness index D and Pielou evenness index J were 1.96±0.34, 1.61±0.50 and 0.77±0.10, respectively. In all four areas of Yangcheng Lake, β- mesosaprobic species comprised the largest share of pollution indicator species. These data suggest that Yangcheng Lake is mesosaprobic.

关键词： rotifer density biomass water quality

甘蔗渣碳气凝胶负载纳米氧化锌的制备及其光催化性能研究

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无机盐工业 2024年第8期56卷 131-138页

作者：张国强戎西林肖振芳薛自然程昊冯军刘泉陆瑶黄文艺广西糖资源绿色加工重点实验室/生物与化学工程学院广西科技大学广西柳州545006 蔗糖产业省部共建协同创新中心广西南宁530004

通过浸渍-煅烧法成功制备出一系列甘蔗渣纤维素基碳气凝胶(BCCA)负载纳米氧化锌复合材料(BCCA/ZnO),并用于降解甲基橙染料(MO)。采用场发射扫描电镜(FE-SEM)、傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)、X射线光电子能谱(XPS)、紫外-... 详细信息

通过浸渍-煅烧法成功制备出一系列甘蔗渣纤维素基碳气凝胶(BCCA)负载纳米氧化锌复合材料(BCCA/ZnO),并用于降解甲基橙染料(MO)。采用场发射扫描电镜(FE-SEM)、傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)、X射线光电子能谱(XPS)、紫外-可见光漫反射(UV-Vis DRS)、N_(2)吸附-脱附等测试方法对制备的BCCA/ZnO进行表征测试。研究结果表明,BCCA具有三维多孔网络状结构,经醋酸锌溶液浸泡、高温碳化后,在其表面原位生成球状纳米ZnO颗粒。在模拟紫外光条件下,BCCA/ZnO具有良好的催化活性,当pH=11时BCCA/ZnO-3可以在80 min内对MO的降解率为99%。重复使用4次后,BCCA/ZnO-3在80 min内对MO的降解率为99%,仍然具有优异的催化效果,表明BCCA/ZnO-3具有较好的稳定性和重复使用性。同时,探究了光催化降解机理,发现·OH起主要作用,h^(+)起次要作用,而·O_(2)^(-)不起作用。

关键词：光催化 ZnO 碳气凝胶甘蔗渣纤维素

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小球藻粉对番茄幼苗生长及土壤性质的影响

中国瓜菜 2024年第6期37卷 135-141页

作者：陈平张紫然张伟张智涵吕晓艳赵吉强汪少丽刘保友烟台大学生命科学学院山东烟台264005 山东省烟台市农业科学研究院山东烟台265500 山东省烟台市中国社科院农村发展研究中心山东烟台265499

为研究小球藻粉作为生物肥料的潜能,以番茄品种红粉佳人为材料,设置叶喷和灌根两种施用方式,探究施用不同浓度的小球藻粉对番茄幼苗生长指标及土壤性质的影响。结果表明,与清水对照相比,小球藻粉500倍稀释液对番茄生长效果最佳,叶喷和... 详细信息

为研究小球藻粉作为生物肥料的潜能,以番茄品种红粉佳人为材料,设置叶喷和灌根两种施用方式,探究施用不同浓度的小球藻粉对番茄幼苗生长指标及土壤性质的影响。结果表明,与清水对照相比,小球藻粉500倍稀释液对番茄生长效果最佳,叶喷和灌根处理后株高、叶片数、生物量和生长函数显著增加2.90%~47.49%,灌根处理效果整体优于叶喷处理;与生物肥料“益施帮”和复合肥“大量元素水溶肥料”相比,小球藻粉500倍液同样表现出生物量和生长函数的显著增加。在改善土壤性质方面,小球藻粉500倍叶喷和灌根处理后土壤pH分别降低0.06、0.29,电导率显著降低8.31%以上;小球藻粉灌根处理番茄后植株地上、地下部位以及土壤中氮素含量增加;小球藻粉叶喷及灌根处理后土壤中蔗糖酶、硝酸还原酶、过氧化氢酶、脲酶、多酚氧化酶、过氧化物酶等酶活性显著提高。研究结果证实小球藻粉叶喷及灌根均适用于番茄生长发育及土壤改良,可为小球藻粉及其他生物肥料的开发应用提供试验依据。

关键词：番茄小球藻幼苗生长土壤性质

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双膦酸盐类药物用于钙化防御治疗的文献分析

罕见病研究 2024年第2期3卷 214-220页

作者：梁春苏王少红张逸舟刘鑫牛子冉史亦丽张波中国医学科学院北京协和医院药剂科北京100730 中国医学科学院北京协和医院疑难重症及罕见病全国重点实验室、国家罕见病医疗质量控制中心北京100730

目的分析双膦酸盐类药物用于钙化防御患者治疗的有效性和安全性。方法检索PubMed、Embase、中国知网及万方数据库,收集报道双膦酸盐用于钙化防御的病例报告,提取患者相关信息进行统计分析。结果纳入文献共18篇病例报告,患者20例,结果显... 详细信息

目的分析双膦酸盐类药物用于钙化防御患者治疗的有效性和安全性。方法检索PubMed、Embase、中国知网及万方数据库,收集报道双膦酸盐用于钙化防御的病例报告,提取患者相关信息进行统计分析。结果纳入文献共18篇病例报告,患者20例,结果显示13例患者(65.0%)采用帕米膦酸盐治疗,4例患者(20.0%)采用依替膦酸盐,2例患者(10.0%)采用阿仑膦酸盐,1例患者(5.0%)采用唑来膦酸。13例患者(65.0%)完全康复,康复时间为0.5~9个月。大部分患者双膦酸盐类药物的耐受性较好(90.0%),1例不耐受帕米膦酸盐的患者在调整给药频次后康复,1例依替膦酸盐高给药剂量患者在停用后指标恢复正常。结论双膦酸盐类药物作为一种骨吸收的抑制剂,兼具有效性和安全性,有望用于钙化防御患者的治疗。

关键词：钙化防御双膦酸盐帕米膦酸盐阿仑膦酸盐唑来膦酸

Rapid and Complete Conversion of CH3NH3PbI3 for Perovskite/C60 Planar-Heterojunction Solar Cells by Two-Step Deposition

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Chinese Journal of Chemistry 2017年第5期35卷 687-692页

作者： Weihai Sun Yunlong Li Weibo Yan Haitao Peng Senyun Ye Haixia Rao ziran Zhao Zhiwei liu Zuqiang Bian Chunhui Huang Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications Peking University Beijing 100871 China

In the present work,we proposed an improved two-step deposition method by optimizing the reaction temperature and the dipping time for the fabrication ofperovskite *** perovskite film fabricated at 70 ℃ exhibits a full surface coverage and a smooth uniform crystal morphology with a particle size up to micrometer *** corresponding inverted perovskite solar cell with a structure of ITO/poly（3,4-ethylenedioxythiophene）：poly（styrene-sulfonate）（PEDOT：PSS）/CH3NH3PbI3/C60/2,9-dimethyl-4,7-diphenyl-l,l 0-phenanthroline （BCP）/Ag displayed a higher power conversion efficiency（PCE）of 13.6%than that of the device fabricated at 20 ℃ （8.06%）,as well as the high *** small but meaningful modification for two-step deposition would provide an efficient and convenient way to optimize planar perovskite solar cells and facilitate the potential applications of perovskite solar cells more widely.

关键词： perovskite solar cell two-step deposition planar

Crafting of plasmonic Au nanoparticles coupled ultrathin BiOBr nanosheets heterostructure: steering charge transfer for efficient CO_(2) photoreduction

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Green Chemical Engineering 2022年第2期3卷 157-164页

作者： Gaopeng liu Lin Wang Xin Chen Xingwang Zhu Bin Wang Xinyuan Xu ziran Chen Wenshuai Zhu Huaming Li Jiexiang Xia School of Chemistry and Chemical Engineering Institute for Energy ResearchJiangsu UniversityZhenjiang212013China Department of Architecture and Environment Engineering Sichuan Vocational and Technical CollegeSuining629000China

Integrating semiconductor photocatalysts with outstanding visible light absorption and fast surface/interface charge transfer kinetics is still an enormous challenge for efficient CO_(2)*** this work,the Au nanoparticles have been coupled with ultrathin BiOBr nanosheets,the formed heterostructure(Au/BiOBr)pos-sesses a localized surface plasmon resonance(LSPR)and enhances the visible light absorption ability,as well as forms a fast charge transport channel on the interface between Au and ***,the heterostructure photo-catalyst exhibits higher photocatalytic CO_(2)to CO performance(135.3/16.43μmol g^(-1))than that of BiOBr(89.0/6.46μmol g^(-1))under 300 W Xe lamp and visible light(λ>400 nm)irradiation for 5 h,***,the in situ FT-IR spectroscopy revealed CO_(2)photoreduction process and found that the*COOH is the key intermediate for CO_(2)to *** work provides an effective method to construct multielectron transfer scheme for efficient photocatalytic CO_(2)reduction.

关键词： Au nanoparticles BiOBr Localized surface plasmon resonance Charge transfer CO_(2)photoreduction

Long-term warming does not affect soil ecoenzyme activity and original microbial nutrient limitation on the Qinghai-Tibet Plateau

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Soil Ecology Letters 2022年第4期4卷 383-398页

作者： Yuanze Li Huakun Zhou Wenjing Chen Yang Wu Lei Lei Qiao ziran Yan GuoBin liu Sha Xue State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China Qinghai Provincial Key Laboratory of Restoration Ecology in Cold Regions Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810000China State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810000China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry Water ResourcesYangling 712100China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China

Microbes play an important role in the carbon cycle and nutrient flow of the soil ***,the response of microbial activities to long-term warming over decades is poorly *** determine how warming changes ecoenzyme activity and microbial nutrient limitation,we conducted a long-term,21 years,experiment,on the Qinghai–Tibet *** selected typical grass-and shrub-covered plots,used fiberglass open-top chambers(OTCs)to raise the temperature,conducted soil sampling at different depths,studied the response of nutrient-acquiring enzyme activity and stoichiometry,and conducted vector analysis of *** results showed that long-term warming did not have a notable effect on the activity of nutrient-acquiring enzymes or enzymatic ***,Spearman correlation analysis indicated a significant and positive correlation between ecoenzyme activity and the available nutrients and microbial biomass in *** analysis of stoichiometry showed phosphorus limitation for all soil microbes at different depths,regardless of whether the soil experienced *** changes in enzymatic stoichiometry and vector analysis suggested that microbial nutrient limitation was not alleviated substantially by long-term warming,and warming did not considerably affect the stratification of microbial nutrient *** research has also shown that long-term warming does not significantly change soil ecoenzyme activity and original microbial nutrient limitation at different soil depths within the OTUsʼimpact *** results could help improve understanding of microbial thermal acclimation and response to future long-term global warming.

关键词： Global warming Ecoenzymatic stoichiometry Microbial nutrient limitation Thermal acclimation Qinghai-Tibet Plateau