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Insulation Design Rule for a Spacer in SF_(6)/N_(2.-filled DC Gas Insulated Apparatus

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 727-735页

作者： Hongyang Zhou guoming Ma Meng Zhang Cong Wang Youping Tu Chengrong Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources and the Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijing 102206China

A recurring challenge of a DC SF_(6)/N_(2.-filled GIS/GIL apparatus is the charge accumulation at DC *** conventional design rules and knowledge of AC spacers may not be applicable for this new type of apparatus.A novel design rule is proposed considering the effect of accumulated charge on the threshold of electric field strength being resistant to the superposed voltage.A surface charge accumulation simulation model is introduced,and the key parameters in the simulation model are *** addition,an experimental platform for a 100 kV spacer flashover test is *** flashover tests under superimposed voltage with opposing polarities are carried out,and the withstanding voltage of the spacer is ***,based on the proposed model,the threshold of the surface electric field strength(tangential component)on the DC spacer in SF_(6)/N_(2. mixed gases is *** a reliable insulation design of a DC GIS/GIL apparatus filled with 0.7 MPa SF_(6)/N_(2.,the threshold of surface electric field strength on the DC spacer is 12.kV/*** insulation design rule can be referenced in the design of a high-voltage DC SF_(6)/N_(2.-filled GIS/GIL apparatus.

关键词： Charge accumulation DC spacer flashover voltage SF_(6)/N_(2. threshold of surface electric field strength

Local field potentials,spiking activity,and receptive fields in human visual cortex

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Science China(Life Sciences) 2024年第3期67卷 543-554页

作者： Lu Luo Xiongfei Wang Junshi Lu Guanpeng Chen guoming Luan Wu Li Qian Wang Fang Fang School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health Peking UniversityBeijing 100871China School of Psychology Beijing Sport UniversityBeijing 100084China Department of Neurosurgery Sanbo Brain HospitalCapital Medical UniversityBeijing 100093China Beijing Key Laboratory of Epilepsy Epilepsy CenterSanbo Brain HospitalCapital Medical UniversityBeijing 100093China IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Peking UniversityBeijing 100871China Beijing Institute for Brain Disorders Beijing 100069China State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China

The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs with intracranial local field potentials(LFPs) and spiking activity in human visual cortex(V1/V2.V3). We recorded LFPs via macro-contacts and discovered that RF sizes estimated from lowfrequency activity(LFA, 0.5–30 Hz) were larger than those estimated from low-gamma activity(LGA, 30–60 Hz) and high-gamma activity(HGA, 60–150 Hz). We then took a rare opportunity to record LFPs and spiking activity via microwires in V1 simultaneously. We found that RF sizes and temporal profiles measured from LGA and HGA closely matched those from spiking activity. In sum, this study reveals that spiking activity of neurons in human visual cortex could be well approximated by LGA and HGA in RF estimation and temporal profile measurement, implying the pivotal functions of LGA and HGA in early visual information processing.

关键词： human visual cortex receptive field intracranial EEG local field potential spiking activity

Optimization of the Use of Spherical Targets for Point Cloud Registration Using Monte Carlo Simulation

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Journal of Geodesy and Geoinformation Science 2024年第2期7卷 18-36页

作者： CHAN Ting On XIAO Hang XIA Linyuan LICHTI Derek D LI Ming Ho DU guoming School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Urbanization and Geo-Simulation Sun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Engineering Research Center for Public Security and Disasters Sun Yat-sen UniversityGuangzhou 510275China Department of Geomatics Engineering Schulich School of EngineeringUniversity of CalgaryCalgary AB T2N 1N4Canada

Registrations based on the manual placement of spherical targets are still being employed by many professionals in the ***,the placement of those targets usually relies solely on personal experience without scientific evidence supported by numerical *** paper presents a comprehensive investigation,based on Monte Carlo simulation,into determining the optimal number and positions for efficient target placement in typical scenes consisting of a pair of *** demonstrates new check-up statistical rules and geometrical constraints that can effectively extract and analyze massive simulations of unregistered point clouds and their corresponding *** than 6×10^(7) sets of the registrations were simulated,whereas more than IOO registrations with real data were used to verify the results of *** results indicated that using five spherical targets is the best choice for the registration of a large typical registration site consisting of two vertical facades and a ground,when there is only a box set of spherical targets *** a result,the users can avoid placing extra targets to achieve insignificant improvements in registration *** results also suggest that the higher registration accuracy can be obtained when the ratio between the facade-to-target distance and target-to-scanner distance is approximately 3:***,the targets should be placed closer to the scanner rather than in the middle between the facades and the scanner,contradicting to the traditional thought. Besides,the results reveal that the accuracy can be increased by setting the largest projected triangular area of the targets to be large.

关键词： point cloud registration Monte Carlo simulation optimalization spherical target

Comprehensive understanding of glioblastoma molecular phenotypes:classification,characteristics,and transition

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Cancer Biology & Medicine 2024年第5期21卷 363-381页

作者： Can Xu Pengyu Hou Xiang Li Menglin Xiao Ziqi Zhang Ziru Li Jianglong Xu guoming Liu Yanli Tan Chuan Fang School of Clinical Medicine Hebei UniversityDepartment of NeurosurgeryAffiliated Hospital of Hebei UniversityBaoding 07100China Hebei Key Laboratory of Precise Diagnosis and Treatment of Glioma Baoding 071000China School of Basic Medical Sciences Hebei UniversityBaoding 07100China Department of Pathology Affiliated Hospital of Hebei UniversityBaoding 07100China

Among central nervous system-associated malignancies,glioblastoma(GBM)is the most common and has the highest mortality *** high heterogeneity of GBM cell types and the complex tumor microenvironment frequently lead to tumor recurrence and sudden relapse in patients treated with *** precision medicine,research on GBM treatment is increasingly focusing on molecular subtyping to precisely characterize the cellular and molecular heterogeneity,as well as the refractory nature of GBM toward *** understanding of the different molecular expression patterns of GBM subtypes is *** have recently proposed tetra fractional or tripartite methods for detecting GBM molecular *** various molecular subtypes of GBM show significant differences in gene expression patterns and biological *** subtypes also exhibit high plasticity in their regulatory pathways,oncogene expression,tumor microenvironment alterations,and differential responses to standard ***,we summarize the current molecular typing scheme of GBM and the major molecular/genetic characteristics of each ***,we review the mesenchymal transition mechanisms of GBM under various regulators.

关键词： Glioblastoma molecular phenotype classification characteristic mesenchymal transition

Sequential pyrolysis for understanding specific influence of cellulose- and lignin-derived volatiles on properties of counterpart char

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Green Chemical Engineering 2024年第2期5卷 222-235页

作者： Yuewen Shao Chao Li Mengjiao Fan guoming Gao Stelgen Inkoua Lijun Zhang Shu Zhang Jun Xiang Song Hu Xun Hu School of Material Science and Engineering University of JinanJinan250022China Joint International Research Laboratory of Biomass Energy and Materials College of Materials Science and EngineeringNanjing Forestry UniversityNanjing210037China State Key Laboratory of Coal Combustion Huazhong University of Science and Technology430074China

Interactions of cellulose-and lignin-derived intermediates have been well documented during pyrolysis of lignocellulosic *** reaction network for the interactions is rather complex,as cellulose-derived volatiles could interact/react with not only lignin-derived volatiles but also lignin-derived char and vice *** probe specifically the impacts of cellulose-derived volatiles on the lignin-derived char or the opposite,herein the sequential pyrolysis was performed by arranging cellulose in the upper bed with lignin in the lower bed or lignin above with cellulose below at 350 and 650℃,*** results indicated that the sequential pyrolysis of cellulose→lignin or lignin→cellulose at 350℃induced increased char yield from formation of carbonaceous deposits via volatiles-char *** with the lignin-derived volatiles,the cellulose-derived volatiles,especially aldehyde fractions,were more reactive towards the lignin-derived char at 350℃,forming oxygen-rich lignin-derived char with a higher yield,an abundance of aliphatic structures and consequently lower thermal *** sequential pyrolysis of lignin→cellulose,more aromatics-rich species were deposited on cellulose-derived char,but the lignin-derived volatiles were less reactive for enhancing the char *** 650℃,instead of polymerisation of the volatiles on the char,either the cellulose-or lignin-derived char catalyzed the cracking of the counterpart volatiles to remove the aliphatic functionalities,which made the char more aromatic and thermally more stable.

关键词： Cellulose Lignin Sequential pyrolysis Char Interaction

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厚煤层柔模混凝土墙沿空巷道支护技术研究

煤炭工程 2024年第10期56卷 186-193页

作者：李刚迟国铭辽宁工程技术大学矿业学院辽宁阜新123000 国能神东煤炭集团有限责任公司大柳塔煤矿陕西神木719315

柔模混凝土墙沿空留巷技术作为无煤柱开采的一种,现已被应用于我国神东矿区多个煤矿。为解决在留巷复用过程中沿空巷道围岩结构稳定性差、变形剧烈、支护难度大的难题,以大柳塔煤矿52.05柔模混凝土墙沿空留巷工作面为工程背景,采用理论... 详细信息

柔模混凝土墙沿空留巷技术作为无煤柱开采的一种,现已被应用于我国神东矿区多个煤矿。为解决在留巷复用过程中沿空巷道围岩结构稳定性差、变形剧烈、支护难度大的难题,以大柳塔煤矿52.05柔模混凝土墙沿空留巷工作面为工程背景,采用理论分析、数值模拟和现场实测相结合的研究方法,研究了柔模混凝土墙沿空巷道的围岩变形特征,建立柔模混凝土墙沿空巷道围岩结构力学模型,得到从巷道掘进阶段至巷道复用阶段沿空巷道全生命使用周期的应力演化规律,并根据巷道不同的使用阶段提出了对应的支护方案。研究结果表明:上覆岩层作用力直接作用在直接顶与混凝土墙岩层接触位置,有利于侧向支承压力传递,巷道围岩变形较大;二次采动超前支承压力导致留巷段前方顶板发生塑性破坏,塑性破坏与底板塑性区联通,将加剧煤壁侧的破坏;现场工程实践表明对沿空巷道进行合理分时分区支护,可改善应力环境,有效控制围岩变形。

关键词：柔模混凝土墙沿空留巷巷道支护围岩控制变形机理

中小学教师浅层情绪表演对工作投入的影响——心理解脱的调节作用

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教育学术月刊 2024年第5期 80-86页

作者：赵娜靖国民太原师范学院教育学院山西晋中030619

提高教师的工作投入是基础教育高质量发展的重要命题。本研究采用情绪劳动量表、工作投入量表和心理解脱量表对山西、吉林、江苏等地的12.60名中小学教师进行抽样调查,分析了中小学教师浅层情绪表演对工作投入的影响,以及心理解脱在其... 详细信息

提高教师的工作投入是基础教育高质量发展的重要命题。本研究采用情绪劳动量表、工作投入量表和心理解脱量表对山西、吉林、江苏等地的12.60名中小学教师进行抽样调查,分析了中小学教师浅层情绪表演对工作投入的影响,以及心理解脱在其中的调节作用。研究发现:中小学教师的浅层情绪表演对工作投入具有显著的负向影响;教师的心理解脱水平在浅层情绪表演和工作投入之间起调节作用。为推进基础教育高质量发展,应重点提升教师的工作投入,促进情绪智力发展,提高心理解脱水平。

关键词：浅层情绪表演工作投入心理解脱中小学教师

基于三线性应变软化模型的综采工作面煤壁片帮深度解析预测

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煤炭科学技术 2024年第7期52卷 1-10页

作者：迟国铭李刚张春会徐刚辽宁工程技术大学矿业学院辽宁阜新123000 河北科技大学河北省岩土与结构体系防灾减灾技术创新中心河北石家庄050018 天地科技股份有限公司开采设计事业部北京100013

为预测综采工作面煤壁片帮深度,以煤壁为研究对象,煤壁煤体视作三线性应变软化材料;将直接顶和基本顶视作宏观顶板,建立了宏观顶板与煤层、支架相互作用的承载力学模型,结合边界条件推导了综采工作面煤壁片帮深度解析计算公式,利用该公... 详细信息

为预测综采工作面煤壁片帮深度,以煤壁为研究对象,煤壁煤体视作三线性应变软化材料;将直接顶和基本顶视作宏观顶板,建立了宏观顶板与煤层、支架相互作用的承载力学模型,结合边界条件推导了综采工作面煤壁片帮深度解析计算公式,利用该公式研究上湾煤矿12.01工作面煤壁片帮情况,分析影响煤壁片帮的因素及影响规律,结果表明:①推导获得的煤壁片帮深度计算公式能够较准确计算综采工作面煤壁片帮深度,能够定量分析顶板特性和支架参数等对煤壁片帮深度的影响。②增加支架初撑力能够降低煤壁片帮深度;增加支架刚度能够降低煤壁片帮深度,但效果较差;增加支架护帮板支护强度,煤壁片帮深度近似线性减小。③顶板厚度和抗拉强度增加,煤壁片帮深度增长,但增长速率随顶板厚度和抗拉强度增加逐渐趋缓。这主要由于顶板厚度和抗拉强度增加,顶板破断步距增大,向采空区内旋转下沉角度增大所致。④综采采高对煤壁片帮深度有很大影响,综采采高增大,煤壁片帮深度近似线性增长。⑤煤体单轴抗压强度增大,煤壁片帮深度减小,顶底板与煤层界面之间的摩擦因数增大,煤壁片帮深度减小。⑥顶板动载系数增大,煤壁片帮深度近似线性增大。

关键词：综采工作面煤壁片帮深度预测液压支架宏观顶板结构

PHYSICAL AGING OF POLYSTYRENE CONFINED IN ANODIC ALUMINUM OXIDE NANOPORES

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PHYSICAL AGING OF POLYSTYRENE CONFINED IN ANODIC ALUMINUM OX...