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跨模态交互融合与全局感知的RGB-D显著性目标检测

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软件学报 2024年第4期35卷 1899-1913页

作者：孙福明胡锡航武景宇孙静王法胜大连民族大学信息与通信工程学院辽宁大连116600

近年来,RGB-D显著性检测方法凭借深度图中丰富的几何结构和空间位置信息,取得了比RGB显著性检测模型更好的性能,受到学术界的高度关注.然而,现有的RGB-D检测模型仍面临着持续提升检测性能的需求.最近兴起的Transformer擅长建模全局信息... 详细信息

近年来,RGB-D显著性检测方法凭借深度图中丰富的几何结构和空间位置信息,取得了比RGB显著性检测模型更好的性能,受到学术界的高度关注.然而,现有的RGB-D检测模型仍面临着持续提升检测性能的需求.最近兴起的Transformer擅长建模全局信息,而卷积神经网络(CNN)擅长提取局部细节.因此,如何有效结合CNN和Transformer两者的优势,挖掘全局和局部信息,将有助于提升显著性目标检测的精度.为此,提出一种基于跨模态交互融合与全局感知的RGB-D显著性目标检测方法,通过将Transformer网络嵌入U-Net中,从而将全局注意力机制与局部卷积结合在一起,能够更好地对特征进行提取.首先借助U-Net编码-解码结构,高效地提取多层次互补特征并逐级解码生成显著特征图.然后,使用Transformer模块学习高级特征间的全局依赖关系增强特征表示,并针对输入采用渐进上采样融合策略以减少噪声信息的引入.其次,为了减轻低质量深度图带来的负面影响,设计一个跨模态交互融合模块以实现跨模态特征融合.最后,5个基准数据集上的实验结果表明,所提算法与其他最新的算法相比具有显著优势.

关键词：显著性目标检测跨模态全局注意力机制 RGB-D检测模型

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阴离子树脂分离橄榄苦苷的过程及性能研究

天然产物研究与开发 2024年第3期36卷 512-519,477页

作者：徐锋曾小成吴学文张有发熊艳湘潭大学化工学院湘潭411105 湖南杰萃生物技术有限公司湘潭412007

目前橄榄苦苷的分离、纯化研究主要集中在大孔吸附树脂,但鲜有阴离子树脂分离、纯化橄榄苦苷的报道。为了研究阴离子树脂(LX-68M)吸附、分离过程及性能,采用吸附动力学及等温吸附模型来研究阴离子树脂静态吸附、解吸橄榄苦苷的行为。结... 详细信息

目前橄榄苦苷的分离、纯化研究主要集中在大孔吸附树脂,但鲜有阴离子树脂分离、纯化橄榄苦苷的报道。为了研究阴离子树脂(LX-68M)吸附、分离过程及性能,采用吸附动力学及等温吸附模型来研究阴离子树脂静态吸附、解吸橄榄苦苷的行为。结果表明阴离子树脂对橄榄苦苷的吸附符合准二级动力学模型(R^(2)=0.9934),Freundlich等温吸附模型(R^(2)=0.9642)。进一步通过动态实验优化阴离子树脂纯化橄榄苦苷工艺,最佳操作工艺为:上样浓度为0.25 g/mL,解吸液为45%乙醇,吸附、解吸速率均为2.0 BV/h。该条件下橄榄苦苷的吸附率、解吸率分别为86.86%、87.08%,纯度为52.33%。此外,阴离子树脂重复使用4次后吸附率为54.9%,经再生处理后,吸附率恢复到93.51%,表明其具有一定的工业化前景。阴离子树脂稳定性好、分离条件温和,适合用于橄榄苦苷及其他相似天然产物的分离纯化。

关键词：橄榄苦苷阴离子树脂吸附动力学等温吸附行为分离

Plasma metabolites and risk of myocardial infarction:a bidirectional Mendelian randomization study

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Journal of Geriatric Cardiology 2024年第2期21卷 219-231页

作者： Dong-Hua LI Qiang wu Jing-Sheng LAN Shuo CHEN You-Yi HUANG Lan-Jin wu Zhi-Qing QIN Ying HUANG Wan-Zhong HUANG Ting ZENG Xin HAO Hua-Bin SU Qiang SU Department of Cardiovascular Medicine Minzu Hospital of Guangxi Zhuang Autonomous RegionGuangxiChina Senior Department of Cardiology the Sixth Medical CenterChinese PLA General HospitalBeijingChina Library of Graduate School Chinese PLA General HospitalBeijingChina Department of Cardiology Jiangbin Hospital of Guangxi Zhuang Autonomous RegionGuangxiChina Health Management Institute the Second Medical CenterChinese PLA General HospitalBeijingChina

BACKGROUND Myocardial infarction(MI)is a critical cardiovascular event with multifaceted etiology,involving several genetic and environmental *** is essential to understand the function of plasma metabolites in the development of MI and unravel its complex *** This study employed a bidirectional Mendelian randomization(MR)approach to investigate the causal relationships between plasma metabolites and MI *** used genetic instruments as proxies for plasma metabolites and MI and conducted MR analyses in both directions to assess the impact of metabolites on MI risk and vice *** addition,the large-scale genome-wide association studies datasets was used to identify genetic variants associated with plasma metabolite(1400 metabolites)and MI(20,917 individuals with MI and 440,906 individuals without MI)*** variance weighted was the primary method for estimating causal *** estimates are expressed as beta coefficients or odds ratio(OR)with 95%*** We identified 14 plasma metabolites associated with the occurrence of MI(P<0.05),among which 8 plasma metabolites[propionylglycine levels(OR=0.922,95%CI:0.881–0.965,P<0.001),gamma-glutamylglycine levels(OR=0.903,95%CI:0.861–0.948,P<0.001),hexadecanedioate(C16-DC)levels(OR=0.941,95%CI:0.911–0.973,P<0.001),pentose acid levels(OR=0.923,95%CI:0.877–0.972,P=0.002),X-24546 levels(OR=0.936,95%CI:0.902–0.971,P<0.001),glycine levels(OR=0.936,95%CI:0.909–0.964,P<0.001),glycine to serine ratio(OR=0.930,95%CI:0.888–0.974,P=0.002),and mannose to trans-4-hydroxyproline ratio(OR=0.912,95%CI:0.869–0.958,P<0.001)]were correlated with a decreased risk of MI,whereas the remaining 6 plasma metabolites[1-palmitoyl-2-arachidonoyl-GPE(16:0/20:4)levels(OR=1.051,95%CI:1.018–1.084,P=0.002),behenoyl dihydrosphingomyelin(d18:0/22:0)levels(OR=1.076,95%CI:1.027–1.128,P=0.002),1-stearoyl-2-docosahexaenoyl-GPE(18:0/22:6)levels(OR=1.067,95%CI:1.027–1.109,P=0.001),alpha-ketobutyrate levels(OR=1.108,95%

关键词： infarction alterations diagnosis

细聚丙烯纤维混凝土介观离散力学模型及其Ⅰ型断裂强度负效应机理

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工程力学 2024年第4期41卷 11-18页

作者：沈雷吴杰邓通发曹茂森徐磊李田雨河海大学水利水电学院江苏南京210024 江西理工大学环境岩土与工程灾害控制重点实验室江西赣州341000 河海大学工程力学系江苏南京210024 滁州学院安徽省桥梁结构数据诊断与智慧运维国际联合研究中心滁州239099

细聚丙烯(PP,直径小于100μm)纤维混凝土Ⅰ型断裂强度随纤维含量增加呈现先增后减的变化规律,其机理尚不明晰。而且由于纤维数量过多,现有数值方法无法精细刻画细纤维混凝土力学行为。对此通过考虑细PP纤维亲水性提升基体局部水灰比的... 详细信息

细聚丙烯(PP,直径小于100μm)纤维混凝土Ⅰ型断裂强度随纤维含量增加呈现先增后减的变化规律,其机理尚不明晰。而且由于纤维数量过多,现有数值方法无法精细刻画细纤维混凝土力学行为。对此通过考虑细PP纤维亲水性提升基体局部水灰比的强度正效应和纤维桥接力强度贡献低于砂浆的强度负效应,并引入纤维直径等效系数(rf),实现介观尺度细聚丙烯纤维混凝土(PFRC)力学行为模拟。研究表明:纤维直径等效系数(rf)建议小于10;当纤维微量添加时,细PP纤维提升基体局部水灰比,使基体强度上升,此时正效应高于负效应;随着纤维含量增加,由于纤维桥接力贡献无法补偿相应面积基体强度,负效应持续增长,PFRC宏观Ⅰ型断裂强度下降。

关键词：细聚丙烯纤维混凝土介观离散模型 Ⅰ型断裂强度

On the Variation of a Metric and Its Application

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Acta Mathematica Sinica,English Series 2010年第10期26卷 2003-2014页

作者： fa En wu Department of Mathematics School of Science Beijing Jiaotong University Beijing 100044 P. R. China

Some of the variation formulas of a metric were derived in the literatures by using the local coordinates system, In this paper, We give the first and the second variation formulas of the Riemannian curvature tensor, Ricci curvature tensor and scalar curvature of a metric by using the moving frame method. We establish a relation between the variation of the volume of a metric and that of a submanifold. We find that the latter is a consequence of the former. Finally we give an application of these formulas to the variations of heat invariants. We prove that a conformally flat metric g is a critical point of the third heat invariant functional for a compact 4-dimensional manifold M, then （M, g） is either scalar flat or a space form.

关键词： Riemannian functional variation of a metric volume variation space form heat invariant

用于位场场源水平边缘增强的均衡形态学滤波器

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Applied Geophysics 2024年第1期21卷 147-156,205页

作者：张建民曾昭发吴燕冈杜威王永志吉林大学地球探测科学与技术学院吉林大学综合信息矿产预测研究所

位场场源水平边缘的增强对于地质构造研究具有重要意义。现有用于源水平边缘增强的滤波器多数基于位场数据的导数构建,但这些滤波器常表现出一些不足,如输出边缘发散、无法均衡强弱异常或结果中存在额外虚假边缘等。本文通过数学形态学... 详细信息

位场场源水平边缘的增强对于地质构造研究具有重要意义。现有用于源水平边缘增强的滤波器多数基于位场数据的导数构建,但这些滤波器常表现出一些不足,如输出边缘发散、无法均衡强弱异常或结果中存在额外虚假边缘等。本文通过数学形态学基本算子的组合叠加,首先定义了基于数学形态学的边缘增强滤波器MMA,为了使该滤波器具备均衡不同振幅异常的能力,提出了MMAZ和MMAT滤波器,通过二者的极大值位置均可实现对位场场源边缘的圈定。合成数据试验结果表明,MMAZ和MMAT滤波器具有很好的均衡能力和抗噪性能,同时相比传统几种滤波器,根据这两种滤波器获得的地质体水平边缘更加清晰收敛,而且针对包含正负异常的地质情况,输出结果中没有额外边缘的产生。最后将这两种新的均衡滤波器应用到老挝万象盆地某钾盐矿区的重力异常和中国西北某金属矿区航磁异常数据的处理中,获得的构造线位置更加准确清晰,从而进一步说明了这两种滤波技术的有效性。

关键词：边缘增强数学形态学位场均衡滤波器

Utilizing sediment grain size characteristics to assess the effectiveness of clay–sand barriers in reducing aeolian erosion in Minqin desert area,China

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Journal of Arid Land 2024年第5期16卷 668-684页

作者： SONG Dacheng ZHAO Wenzhi LI Guangyu WEI Lemin WANG Lide YANG Jingyi wu Hao MA Quanlin College of Forestry Gansu Agricultural UniversityLanzhou 730070China Gansu Hexi Corridor Forest Ecosystem National Research Station Gansu Desert Control Research InstituteLanzhou 730070China Linze Inland River Basin Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 ***,studies on evaluating the long-term effectiveness of clay–sand barriers against aeolian erosion,particularly from the perspective of surface sediment grain size,are limited and thus insufficient to ascertain the protective impact of these barriers on regional aeolian *** study focused on the surface sediments(topsoil of 0–3 cm depth)of clay–sand barriers in Minqin desert area to explain their erosion resistance from the perspective of surface sediment grain *** March 2023,six clay–sand barrier sampling plots with clay–sand barriers of different deployment durations(1,5,10,20,40,and 60 a)were selected as experimental plots,and one control sampling plot was set in an adjacent mobile sandy area without sand *** sediment samples were collected from the topsoil of each sampling plot in the study area in April 2023 and sediment grain size characteristics were *** indicated a predominance of fine and medium sands in the surface sediments of the study *** deployment of clay–sand barriers cultivated a fine quality in grain size composition of the regional surface sediments,increasing the average contents of very fine sand,silt,and clay by 30.82%,417.38%,and 381.52%,*** trend became markedly pronounced a decade after the deployment of clay–sand *** effectiveness of clay–sand barriers in erosion resistance was manifested through reduced wind velocity,the interception of sand flow,and the promotion of fine surface sediment *** particles such as medium,coarse,and very coarse sands predominantly accumulated on the external side of the barriers,while finer particles such as fine and very fine sands concentrated in the upwind(northwest)region of the *** contrast,the contents of finest particles such as silt and clay were higher in the downwind

关键词： clay-sand barriers sediment grain size grain size distribution aeolian erosion windbreak and sand fixation Minqin desert area

盐分环境下水性混凝土防腐涂层失效规律对比研究

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公路交通科技 2024年第1期41卷 44-53页

作者：杨明达王来发吴永畅樊涛青海省交控建设工程集团有限公司青海西宁810021 长安大学陕西西安710061 西安华泽道路材料有限公司陕西西安710065

为实现分析混凝土结构物水性防腐涂层的服役效果和预期寿命,充分考虑盐渍土地区温度交替变化大、盐分环境多样等影响因素,进行混凝土防腐涂层的长期失效规律研究。本研究通过涂装3种体系的水性混凝土防腐涂层,对其干湿循环和长期浸泡状... 详细信息

为实现分析混凝土结构物水性防腐涂层的服役效果和预期寿命,充分考虑盐渍土地区温度交替变化大、盐分环境多样等影响因素,进行混凝土防腐涂层的长期失效规律研究。本研究通过涂装3种体系的水性混凝土防腐涂层,对其干湿循环和长期浸泡状态下的涂层宏观形貌、微观表面形貌进行分析,并测试不同循环周期下的涂层光泽度、色差值、附着力等指标,采用logistic曲线、S型曲线和二次函数曲线分别对涂层的光泽度、色差和附着力分别拟合分析并预测服役寿命。结果表明:水性环氧涂层(ES)、水性氟碳涂层(FS)、水性丙烯酸涂层(AS)在长时间盐分作用下均逐渐失效,均产生涂层孔隙扩大,内部填料流失,涂层分层断裂的过程;其中FS涂层、ES涂层和AS涂层在干湿循环60 d后完全失光,70 d后明显变色,在长期浸泡90 d后颜色变化趋近平缓,其各自涂层的附着力随干湿循环周期增加也逐渐下降;通过光泽度、色差和附着力指标进行系数加权的方法所预测的FS,ES,AS涂层寿命分别为2.45,2.48,2.74 a,与实际盐分环境下涂层寿命接近。所建寿命预测加权分析方法能较好地反映不同树脂类型涂层的盐分腐蚀规律,可为盐渍土地区准确评估实际环境影响因素下混凝土腐蚀行为及涂层防护效果提供依据。

关键词：道路工程失效规律干湿循环防腐涂层盐分环境

Enhancing Geological Understanding and Identifying Gold Anomalies in the Ailaoshan Orogen

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 441-453页

作者： ZHAO Shiyu YANG Lin SONG Yiwei DONG Yuntao FENG Lihao LI Huajian wu Junyu WANG Qingfei State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Xi’an Center of Mineral Resources Survey China Geological SurveyXi’an 710010China Yunnan Gold Mining Industry Group Kunming 650299China Jiangxi Provincial Key Laboratory of Genesis and Prospect for Strategic Minerals East China University of TechnologyNanchang 330013China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China

The Ailaoshan Orogen in the southeastern Tibet Plateau,situated between the Yangtze and Simao blocks,underwent a complex structural,magmatic,and metamorphic evolution resulting in different tectonic subzones with varying structural lineaments and elemental *** elements can conceal or reduce anomalies due to the mutual effect between different anomaly *** the whole zone into subzones based on tectonic settings,ore cluster areas,or sample catchment basins(Scb),geochemical and structural anomalies associated with gold(Au)mineralization have been identified utilizing mean plus twice standard deviations(Mean+2STD),factor analysis(fa),concentration-area(CA)modeling of stream sediment geochemical data,and lineament density in both the Ailaoshan Orogen and the individual *** fa in the divided 98 Scbs with 6 Scbs containing Au deposits can roughly ascertain unknown rock types,identify specific element associations of known rocks and discern the porphyry or skarn-type Au *** with methods of Mean+2STD and C-A model of data in the whole orogen,which mistake the anomalies as background or act the background as anomalies,the combined methods of fa and C-A in the separate subzones or Scbs works well in regional metallogenic potential *** of lineament densities with a 10-km circle diameter is not suitable to locate Au deposits because of the delineated large areas of medium-high lineament *** contrast,the use of circle diameters of 1.3 km or 1.7 km in the ore cluster scale delineates areas with a higher concentration of lineament density,consistent with the locations of known Au *** analyzing the map of faults and Au anomalies,two potential prospecting targets,Scbs 1 and 63 with a sandstone as a potential host rock for Au,have been identified in the Ailaoshan *** use of combined methods in the divided subzones proved to be more effective in improving geological understanding and identifying

关键词： minerology geochemistry gold stream sediment sample catchment basin concentration-area model lineament density Ailaoshan Orogen