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矸石膏体流动与强度性能试验研究

有色金属（矿山部分） 2024年第5期76卷 74-81,92页

作者：巴蕾卓庆奉王晶王奇峰肖柏林鄂尔多斯职业学院内蒙古鄂尔多斯017000 神东煤炭集团公司陕西榆林719300 北京科技大学土木与资源工程学院北京100083

目的:为了利用煤矸石制备膏体,探索煤矸石无废化源头处理技术。方法:通过室内实验研究了膏体制备参数、物料组成及掺量对膏体流动工作特性、强度特性的影响。结果:结果表明:随着粉煤灰替代水泥百分比增加,膏体塌落度和泌水率均先降低后... 详细信息

目的:为了利用煤矸石制备膏体,探索煤矸石无废化源头处理技术。方法:通过室内实验研究了膏体制备参数、物料组成及掺量对膏体流动工作特性、强度特性的影响。结果:结果表明:随着粉煤灰替代水泥百分比增加,膏体塌落度和泌水率均先降低后增加,28 d强度却线性降低;低品质粉煤灰可作为细骨料改善膏体的级配,膏体的塌落度和泌水率随粉煤灰细骨料的增加分别线性增加和对数下降,当粉煤灰与煤矸石比例为1∶2时,具有最高28 d强度3.32 MPa,且满足自流输送要求;其余不变时,随水泥增加,膏体塌落度增加,泌水率降低,流动性增强,强度呈对数函数形式上升;固定水泥∶粉煤灰∶煤矸石=1∶3∶6,膏体的塌落度与泌水率均随着质量浓度的增加而线性降低;而强度随浓度的增加而线性增加。结论:研究可为煤矸石膏体充填的设计与工程应用提供理论依据与技术支撑。

关键词：煤矸石膏体充填工作特性强度

Semi-supervised remote sensing image scene classification with prototype-based consistency

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Chinese Journal of Aeronautics 2024年第2期37卷 459-470页

作者： Yang LI Zhang LI Zi wang Kun wang qifeng YU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Deep learning significantly improves the accuracy of remote sensing image scene classification,benefiting from the large-scale ***,annotating the remote sensing images is time-consuming and even tough for *** neural networks trained using a few labeled samples usually generalize less to new unseen *** this paper,we propose a semi-supervised approach for remote sensing image scene classification based on the prototype-based consistency,by exploring massive unlabeled *** this end,we,first,propose a feature enhancement module to extract discriminative *** is achieved by focusing the model on the foreground ***,the prototype-based classifier is introduced to the framework,which is used to acquire consistent feature *** conduct a series of experiments on NWPU-RESISC45 and Aerial Image Dataset(AID).Our method improves the State-Of-The-Art(SOTA)method on NWPU-RESISC45 from 92.03%to 93.08%and on AID from 94.25%to 95.24%in terms of accuracy.

关键词： Semi-supervised learning Remote sensing Scene classification Prototype network Deep learning

基于组合赋权-云模型的毕达哥拉斯模糊语言综合评价方法研究

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科技和产业 2024年第9期24卷 176-182页

作者：叶梦依陈岚辉何望琳王琦峰浙江万里学院物流与电子商务学院浙江宁波315100

评价本身具有随机性、模糊性以及不确定性的特点。为了避免评价过程太过主观,提出一种基于组合赋权和云模型的毕达哥拉斯模糊语言综合评价方法。针对专家给出的属性值为毕达哥拉斯模糊语言,根据CRITIC-G1(标准间相关性的重要性-序关系分... 详细信息

评价本身具有随机性、模糊性以及不确定性的特点。为了避免评价过程太过主观,提出一种基于组合赋权和云模型的毕达哥拉斯模糊语言综合评价方法。针对专家给出的属性值为毕达哥拉斯模糊语言,根据CRITIC-G1(标准间相关性的重要性-序关系分析)法对评价指标进行主客观赋权,由博弈论算法计算权重最优的组合系数得出组合权重。最后构建毕达哥拉斯模糊云模型决策矩阵进行信息集结。通过案例计算分析表明,该方法优化了复杂情境下的决策,具有其可行性和有效性。

关键词：毕达哥拉斯模糊语言序关系分析(G1)法标准间相关性的重要性(CRITIC)法博弈论组合赋权云模型综合评价方法

多维参数融合技术在核电应急柴油机状态监测及故障诊断中的应用研究

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中国核电 2024年第2期17卷 157-164页

作者：王启峰陈锋李聿容周航周鑫核电运行研究(上海)有限公司上海200120 中国船舶集团有限公司第七一一研究所上海201108

介绍了一种融合振动、气缸压力、转速、油液和热工等多维参数分析技术的核电厂应急柴油机状态监测和故障诊断系统。通过提取振动特征参数、气缸压力特征参数及转速特征参数,并融合润滑油监测参数和热工监测参数,在柴油机故障机理分析的... 详细信息

介绍了一种融合振动、气缸压力、转速、油液和热工等多维参数分析技术的核电厂应急柴油机状态监测和故障诊断系统。通过提取振动特征参数、气缸压力特征参数及转速特征参数,并融合润滑油监测参数和热工监测参数,在柴油机故障机理分析的基础上建立了故障规则及各参数的关联,形成了一套较为完善的柴油机故障数据库,实现了应急柴油机组的故障智能诊断和辅助决策功能。通过工程应用测试,验证了对涡轮增压器轴承松动、单缸失火和敲缸等故障的监测与诊断能力,为核电应急柴油发电机组状态监测和故障诊断提供了坚实的基础。

关键词：应急柴油发电机组状态监测故障诊断特征提取

基于机器视觉的煤炭运输列车车厢状态智能检测方法

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自动化应用 2024年第15期65卷 62-66,69页

作者：陈小霞李锁弟朱良恺张东伟王祁峰枣庄矿业(集团)有限责任公司煤炭洗选加工中心山东枣庄277000

提出基于机器视觉的煤炭运输列车车厢状态智能检测方法,该方法能及时发现安全隐患并进行预警,提升检车效率,有效预防事故的发生,保障煤炭运输的安全。利用线阵相机等设备采集煤炭运输列车车厢的原始图像;利用Retinex算法增强列车车厢原... 详细信息

提出基于机器视觉的煤炭运输列车车厢状态智能检测方法,该方法能及时发现安全隐患并进行预警,提升检车效率,有效预防事故的发生,保障煤炭运输的安全。利用线阵相机等设备采集煤炭运输列车车厢的原始图像;利用Retinex算法增强列车车厢原始图像,提升图像质量;采用索贝尔算子对图像中的车厢实施切分处理,得到每一节完整的车厢图片,用于后续的车厢状态检测;构建YOLOv5算法,并提出一种抑制异类冗余框的方法,对其实施改进,利用改进后的方法完成对煤炭运输列车车厢状态的智能检测,并将检测结果应用于车厢异常报警中。实验证明,该方法能够精准检测煤炭运输列车车厢状态,并及时发出报警信息,在mAP和FPS方面均有较好的表现。

关键词：机器视觉车厢状态智能检测图像增强车厢切分 YOLOv5算法

Compromised small-world efficiency of structural brain networks in schizophrenic patients and their unaffected parents

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Neuroscience Bulletin 2015年第3期31卷 275-287页

作者： Hao Yan Lin Tian qifeng wang Qiang Zhao Weihua Yue Jun Yan Bing Liu Dai Zhang Peking University Six Hospital Peking University Institute of Mental Health Key Laboratory of Mental Health Ministry of Health (Peking University) LIAMA Center for Computational Medicine National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Department of Radiology The Third Hospital Peking University Peking-Tsinghua Center for Life Sciences PKU-IDG/Mc Govern Institute for Brain Research Peking University

Several lines of evidence suggest that efficient information integration between brain regions is disrupted in schizophrenia. Abnormalities in white matter tracts that interconnect brain regions may be directly relevant to this pathophysiological process. As a complex mental disorder with high heritability, mapping abnormalities in patients and their first- degree relatives may help to disentangle the risk factors for schizophrenia. We established a weighted network model of white matter connections using diffusion tensor imaging in 25 nuclear families with schizophrenic probands （19 patients and 41 unaffected parents） and two unrelated groups of normal controls （24 controls matched with patients and 26 controls matched with relatives）. The patient group showed lower global efficiency and local efficiency. The decreased regional efficiency was localized in hubs such as the bilateral frontal cortices, bilateral anterior cingulate cortices, and left precuneus. The global efficiency was negatively correlated with cognition scores derived from a 5-factor model of schizophrenic *** also found that unaffected parents displayed decreased regional efficiency in the right temporal cortices, left supplementary motor area, left superior temporal pole, and left thalamus. The global efficiency tended to be lower in unaffected parents. Our data suggest that （1） the global efficiency loss in neuroanatomical networks may be associated with the cognitive disturbances in schizophrenia; and （2） genetic vulnerability to schizophrenia may influence the anatomical organization of an individual＇s brain networks.

关键词： network analysis diffusion tensorimaging tractography white matter small-worldarchitecture

AstroPose:Astronaut pose estimation using a monocular camera during extravehicular activities

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Science China(Technological Sciences) 2024年第6期67卷 1933-1945页

作者： LIU ZiBin LI You wang ChunHui LIU Liang GUAN BangLei SHANG Yang YU qifeng College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China Key Laboratory of Human Factors Engineering China Astronaut Research and Training CenterBeijing100094China

With the completion of the Chinese space station,an increasing number of extravehicular activities will be executed by astronauts,which is regarded as one of the most dangerous activities in human space *** guarantee the safety of astronauts and the successful accomplishment of missions,it is vital to determine the pose of astronauts during extravehicular *** article presents a monocular vision-based pose estimation method of astronauts during extravehicular activities,making full use of the available observation ***,the camera is calibrated using objects of known structures,such as the spacesuit backpack or the circular handrail outside the space ***,the pose estimation is performed utilizing the feature points on the *** proposed methods are validated both on synthetic and semi-physical simulation experiments,demonstrating the high precision of the camera calibration and pose *** further evaluate the performance of the methods in real-world scenarios,we utilize image sequences of Shenzhou-13 astronauts during extravehicular *** experiments validate that camera calibration and pose estimation can be accomplished solely with the existing observation resources,without requiring additional complicated *** motion parameters of astronauts lay the technological foundation for subsequent applications such as mechanical analysis,task planning,and ground training of astronauts.

关键词： monocular camera astronaut pose estimation camera calibration

Biaxial tensile behavior of CoCrFeNi high-entropy alloy under dynamic and proportional loadings

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Chinese Journal of Aeronautics 2024年第9期37卷 475-489页

作者： Haoyang LI Liqiang GAO Lin QI Yajing FENG Jingyu wang Yulong LI qifeng YU School of Aeronautics.Nort/western Polytechnical University Xiana 710072China Shaanxi Key Laboratory of Impact Dynamics and Engineering Applications Northwestern Polytechnical UniversityXian 710072 China School of Civil Aviation Northwestern Polytechnical UniversitySuzhou 215699China NPU Yangzi River Delta Research Institute Suzhou 215400China

The dynamic failure behavior of CoCrFeNi High-Entropy Alloy(HEA)under plane biaxial stress was investigated in *** dynamic biaxial tensile tests were conducted using an Electromagnetic Biaxial Split Hopkinson Tensile Bar(EBSHTB)*** comparison,the quasi-static uniaxial and biaxial tensile tests,as well as dynamic uniaxial tensile tests,were per-formed respectively.A cruciform specimen suitable for large plastic deformation was designed and employed in the *** Finite Element Method(FEM)verified that the improved cruciform specimen could satisfy the basic *** feasibility of the proposed specimen was further confirmed through loading ***,the quasi-static and dynamic yield loci of the HEA in the first quadrant of the principal stress space were *** results indicate that the alloy exhibits obvious strain hardening effect and strain rate strengthening effect,the yield locus and plastic work contours can be accurately described by Hill'48 criterion.

关键词： High-entropy alloys Biaxial tensile test Cruciform specimen Electromagnetic split Hop-kinson bar Digital image correlation

维普期刊数据库评论

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秋葵属植物多糖的研究进展

食品工业 2024年第7期45卷 181-185页

作者：李慧岳柯昕王其凤冯小燕严天文张涛重庆师范大学生命科学学院重庆401331

秋葵属植物多糖作为一种天然产物,由于其具有抗癌、抗氧化、抗病毒、降脂和免疫调节等功能,已受到国内外研究者的广泛关注。文章对近几年有关秋葵属植物多糖的研究进行总结,并对其开发利用前景进行展望,目的是为秋葵属植物多糖的研究和... 详细信息

秋葵属植物多糖作为一种天然产物,由于其具有抗癌、抗氧化、抗病毒、降脂和免疫调节等功能,已受到国内外研究者的广泛关注。文章对近几年有关秋葵属植物多糖的研究进行总结,并对其开发利用前景进行展望,目的是为秋葵属植物多糖的研究和开发提供科学依据。

关键词：植物多糖提取方法分离纯化生物活性应用