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Power system transient stability assessment based on the multiple paralleled convolutional neural network and gated recurrent unit

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Protection and Control of Modern Power Systems 2022年第1期7卷 586-601页

作者： Shan cheng zihao Yu Ye Liu Xianwang Zuo College of Electrical Engineering and New Energy China Three Gorges UniversityYichang 443002HubeiChina

In order to accurately evaluate power system stability in a timely manner after faults,and further improve the feature extraction ability of the model,this paper presents an improved transient stability assessment(TSA)method of CNN+*** comprises a convolutional neural network(CNN)and gated recurrent unit(GRU).CNN has the feature extraction capability for a micro short-term time sequence,while GRU can extract characteristics contained in a macro long-term time *** two are integrated to comprehensively extract the high-order features that are contained in a transient *** overcome the difficulty of sample misclassification,a multiple parallel(MP)CNN+GRU,with multiple CNN+GRU connected in parallel,is ***,an improved focal loss(FL)func-tion which can implement self-adaptive adjustment according to the neural network training is introduced to guide model ***,the proposed methods are verified on the IEEE 39 and 145-bus *** simulation results indicate that the proposed methods have better TSA performance than other existing methods.

关键词： Transient stability assessment MP CNN+GRU Sample misclassification Improved focal loss function

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防裂抗渗剂对混凝土早期开裂及抗渗性的影响

新型建筑材料 2021年第8期48卷 155-158页

作者：郭相伟喻林谭涛陈韦凌程梓豪河海大学力学与材料学院江苏南京210098

为探究新型防裂抗渗剂对混凝土早期开裂及抗渗性的影响,通过孔隙率试验、抗水渗透试验和平板试验,研究混凝土的孔隙率、抗渗性及早期抗裂性的变化规律。结果表明:HPT-X防裂抗渗剂对提高混凝土的抗渗性,降低孔隙率有较明显的改善作用,随... 详细信息

为探究新型防裂抗渗剂对混凝土早期开裂及抗渗性的影响,通过孔隙率试验、抗水渗透试验和平板试验,研究混凝土的孔隙率、抗渗性及早期抗裂性的变化规律。结果表明:HPT-X防裂抗渗剂对提高混凝土的抗渗性,降低孔隙率有较明显的改善作用,随着HPT-X掺量的增加,混凝土的早期抗裂性不断提高,HPT-X的最优掺量为1.0 kg/m^(3)。

关键词：防裂抗渗材料抗渗性抗裂性能孔隙率

离心训练结合不同频率全身振动训练治疗髌腱末端病

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中国组织工程研究 2024年第4期28卷 493-498页

作者：蒋子豪王广兰陈鹏孙像鸿王婷贾绍辉郑成株洲市中心医院康复治疗科湖南省株洲市412007 武汉体育学院运动医学院湖北省武汉市430079 株洲市银海学校湖南省株洲市412007 武汉体育学院运动训练监控湖北省重点实验室湖北省武汉市430079 武汉体育学院医院运动医学科湖北省武汉市430079

背景:已有大量研究探讨了不同频率全身振动训练对肌力的影响,但对不同频率振动训练对髌腱末端病的疗效差异的研究较少。目的:探究股四头肌离心训练结合不同频率的全身振动训练对髌腱末端病患者的疗效。方法:2022年4-6月于武汉体育学院... 详细信息

背景:已有大量研究探讨了不同频率全身振动训练对肌力的影响,但对不同频率振动训练对髌腱末端病的疗效差异的研究较少。目的:探究股四头肌离心训练结合不同频率的全身振动训练对髌腱末端病患者的疗效。方法:2022年4-6月于武汉体育学院招募髌腱末端病患者48例,随机分为离心训练组、30 Hz组、40 Hz组、50 Hz组,每组12例。离心训练组仅完成股四头肌离心训练,30 Hz组、40 Hz组、50 Hz组在股四头肌离心训练的基础上进行振幅2 mm,频率分别为30,40,50 Hz的全身振动训练,干预8周,每周3次。在干预前后评定患者股四头肌表面肌电信号、跳深着陆触地时刻和垂直地反力峰值时刻膝关节的运动学和动力学数据、目测类比评分及维多利亚评分量表评分。结果与结论:①干预后与离心训练组相比,40 Hz和50 Hz组股外侧肌和股内侧肌中频值显著提高(P<0.05);②干预后触地时刻,40 Hz组和50 Hz组膝关节屈曲角度和外旋力矩显著低于离心训练组(P<0.05);50 Hz组膝关节屈曲角度显著低于30 Hz组(P<0.05);垂直地反力峰值时刻,40 Hz组膝关节伸膝力矩显著低于离心训练组(P<0.05);50 Hz组膝关节屈曲角度和伸膝力矩显著低于离心训练组(P<0.05);③干预后50 Hz组和40 Hz组目测类比评分显著低于离心训练组(P<0.05);④干预后50 Hz组维多利亚评分量表评分显著高于离心训练组和30 Hz组(P<0.05);⑤结果说明:股四头肌离心训练结合50 Hz振动训练可以显著改善髌腱末端病患者股四头肌力量、肌耐力和股内侧肌激活率,降低膝关节疼痛,提高膝关节功能。

关键词：髌腱末端病离心训练全身振动训练

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安庆市宜秀区景观生态安全格局构建

安徽科技学院学报 2023年第2期37卷 109-116页

作者：袁平何胜程梓昊张官进张振国安徽科技学院资源与环境学院安徽凤阳233100

目的:生态安全格局构建是实现区域生态安全、维持区域可持续发展的重要途径,为给安庆市宜秀区生态环境建设提供科学依据和景观生态安全格局优化方法提供参考。方法:采用粒度反推法及Fragstats 4.2软件识别生态源地,采用最小阻力模型构... 详细信息

目的:生态安全格局构建是实现区域生态安全、维持区域可持续发展的重要途径,为给安庆市宜秀区生态环境建设提供科学依据和景观生态安全格局优化方法提供参考。方法:采用粒度反推法及Fragstats 4.2软件识别生态源地,采用最小阻力模型构建最小累计阻力面,基于电路理论、ArcGIS水文分析方法等得到“生态廊道”“夹点”“障碍点”。结果:400 m粒度的生态栅格是宜秀区生态源地选取的最适宜尺度。在400 m粒度尺度下,宜秀区生态源地22个,总面积177.16 hm^(2),生态廊道38条,全长56.3 km,“夹点”“障碍点”分别为5、38个。结论:通过对“夹点”的识别、“生态廊道”的提取、“夹点”的保护和“障碍点”的修复,宜秀区的景观生态格局将得到进一步的改善,该研究可为县域尺度下景观生态安全格局构建提供借鉴。

关键词：生态安全格局粒度反推法最小阻力模型电路理论生态源地生态节点

基于非靶向代谢组学的信阳毛尖茶加工过程非挥发物代谢轮廓分析

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食品科学 2024年第5期45卷 102-110页

作者：孔亚帅陈凌芝成恩朱尧王晶晶王晓王子浩陈义尹鹏郭桂义信阳农林学院茶学院河南省豫南茶树资源综合开发重点实验室河南信阳464000 信阳市文新茶叶有限责任公司河南信阳464000

为了解信阳毛尖茶在加工过程中非挥发性代谢物的变化规律,以信阳群体种鲜叶为原料,采用非靶向代谢组学技术对信阳毛尖茶加工过程样品进行系统分析。结果显示,在信阳毛尖茶加工过程中共对比鉴定出1000种非挥发性代谢物,多元统计分析表明... 详细信息

为了解信阳毛尖茶在加工过程中非挥发性代谢物的变化规律,以信阳群体种鲜叶为原料,采用非靶向代谢组学技术对信阳毛尖茶加工过程样品进行系统分析。结果显示,在信阳毛尖茶加工过程中共对比鉴定出1000种非挥发性代谢物,多元统计分析表明信阳毛尖茶在杀青后其非挥发性代谢物发生显著变化;同时共筛选出53个差异化合物,其中氨基酸、儿茶素、黄酮糖苷、脂质、嘌呤核苷、有机酸等化合物的转化是形成信阳毛尖茶风味和品质的关键;尤其是一些酰化黄酮糖苷、溶血磷脂酰类、嘌呤核苷类化合物在杀青后相对含量显著提升;京都基因与基因组百科全书代谢通路富集分析结果显示,差异化合物在嘌呤代谢,甘油磷脂代谢,苯丙氨酸代谢,氨酰基-tRNA生物合成,苯丙氨酸、酪氨酸和色氨酸生物合成和甘氨酸、丝氨酸和苏氨酸代谢这些代谢通路中显著富集(P<0.05)。本研究进一步挖掘了影响信阳毛尖茶风味和品质的主要非挥发性代谢物,为揭示信阳毛尖茶风味和品质形成机制提供依据和参考。

关键词：非靶向代谢组学信阳毛尖茶加工过程非挥发性代谢物

Design of the real-time detection system based on LabVIEW for no-till seeder working performance

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 100-106页

作者： Huibin Zhu cheng Qian zihao Guo Lizhen Bai Faculty of Agriculture and Food Kunming University of Science and Technology.Kunming 650500China

In order to ensure the working performance of the seeder,reduce the labor intensity of manual testing,and improve the efficiency and accuracy of the detection,a real-time detection system for detecting the performance of no-till seeders was designed based on the LabVIEW software platform of virtual instrument technology and the MCC USB-231 data acquisition *** detection system can be used to detect the seeding quality index and residue cover *** detection of the seeding quality index included the middle detection between the metering device and the opener,the end detection between the opener and the *** result of the field test showed that the detection accuracies of seed quantity,multiple index,and miss index were 94.51%,92.83%,and 91.81%,*** fault position can be accurately determined,and the measurement accuracy of residue cover index was 94.54%.The working performance of the no-tillage seeder can be monitored by the detection system to avoid the occurrence of reseeding and miss-seeding and improve production efficiency.

关键词： LabVIEW no-tillage seeder seeding quality real-time detection residue cover index

基于220kV GIS间隔双断口母线隔离开关技术的试验方法研究

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湖南电力 2020年第5期40卷 15-18,24页

作者：程子豪吴丹曾凡兴付磊杨洸孙铭湖北省电力勘测设计院有限公司湖北武汉430040

220kV GIS母线双断口隔离开关作为一种新型设备,能有效解决GIS间隔在改扩建时母线停电的顽疾。目前该新型设备的针对性试验方案还不完善,将传统GIS试验方案应用于新型双断口母线隔离开关设备中,并分析其利弊。在此基础上利用双母线作为... 详细信息

220kV GIS母线双断口隔离开关作为一种新型设备,能有效解决GIS间隔在改扩建时母线停电的顽疾。目前该新型设备的针对性试验方案还不完善,将传统GIS试验方案应用于新型双断口母线隔离开关设备中,并分析其利弊。在此基础上利用双母线作为桥梁,充分利用双断口母线隔离开关的自身特性,提出一种新型试验方案,可在变电站一期建设时完整地对备用间隔双断口母线隔离开关进行耐压试验。

关键词：双断口隔离开关耐压试验扩建不停电

3D fluorescence emission difference microscopy based on spatial light modulator

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Journal of Innovative Optical Health Sciences 2016年第3期9卷 83-92页

作者： Guangyuan Zhao zihao Rong Cuifang Kuang cheng Zheng Xu Liu State Key Laboratory of Modern Optical Instrumentation College of Optical Science and Engineering Zhejiang University Hangzhou 310027P.R.China

We report three-dimensional fluorescence emission difference(3D-FED)microscopy using a spatial light modulator(SLM).Zero phase,0–2vortex phase and binary 0-pi phase are loaded on the SLM to generate the corresponding solid,doughnut and z-axis hollow excitation spot,*** technique achieves super-resolved image by subtracting three di®erently acquired images with proper subtractive *** theoretical analysis and simulation tests are proceeded to testify the performance of ***,the improvement of lateral and axial resolution is demonstrated by imaging 100 nm°uorescent *** experiment yields lateral resolution of 140 nm and axial resolution of approximate 380 nm.

关键词： Super-resolution fluorescence imaging 3D-FED microscopy spatial light modulator

Mechanical properties and damage characteristics of solidified body-coal combination in continuous driving and gangue backfilling

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International Journal of Mining Science and Technology 2023年第10期33卷 1217-1228页

作者： Yi Tan Hao cheng Wenbing Guo Erhu Bai Shaopu Zhang Yu Wang zihao Li School of Energy Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China State Collaborative Innovation Center of Coal Work Safety and Clean-Efficiency Utilization Henan Polytechnic UniversityJiaozuo 454000China

Recovery of the coal buried under buildings,railways and water bodies and the residual coal in irregularly arranged fully mechanized mining faces is a common engineering problem facing underground coal *** this study,a mining technology of continuous driving and gangue backfilling(CDGB)was *** technology,which can not only alleviate ground subsidence and gangue discharge,but also release the above-mentioned coals,contributes to green and efficient sustainable development of *** stability of the system of the solidified body-reserved coal pillar combination(S-C combination)is crucial to the CDGB ***,it is of great significance to explore the mechanical and damage characteristics of S-C combination in the synergistic bearing ***,four sets of differentshaped S-C combination specimens were fabricated and a S-C combination bearing structure in CDGB was constructed to explore the differences in mechanical characteristics and damage modes of different-shaped S-C combination specimens during ***,their surface strain field evolutions and acoustic emission(AE)response characteristics in the load-bearing process were obtained with the aid of the digital image correlation technique and the AE signal monitoring ***,a damage evolution model based on AE parameters and mechanical parameters was established to clarify the damage evolution *** following results were obtained:(1)The free area of S-C combination can serve as a quantitative index to evaluate the stability of the overburden control system;(2)The concept of critical value k of the free area was first *** the free area exceeds the critical value k(free area ratio greater than 1.13),the deformation resistance and the free area changes becomes negatively correlated;(3)As the free area expands,the failure of the S-C combination specimen evolves from tensile failure to shear *** distribution characteristics of the axial strain f

关键词： Continuous driving and gangue backfilling Solidified body-coal combination Mechanical properties Damage characteristics Digital image correlation technology Acoustic emission