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基于FRAME法的云南古村镇火灾风险评估
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作者 李伟燕 郑飞扬 张健 《建筑技术》 2025年第9期1129-1132,共4页
考虑云南古村镇建筑群的火灾特性,开展火灾风险评估工作对云南古村镇的保护具有重要意义。以云南丽江市白沙古镇的火灾风险评估工作为例,通过现场勘查和无人机三维实景模型获取相关火灾数据,在此基础上利用FRAME法分析了单体建筑的火灾... 考虑云南古村镇建筑群的火灾特性,开展火灾风险评估工作对云南古村镇的保护具有重要意义。以云南丽江市白沙古镇的火灾风险评估工作为例,通过现场勘查和无人机三维实景模型获取相关火灾数据,在此基础上利用FRAME法分析了单体建筑的火灾风险。结果表明:白沙古镇的消防安全改造方向因子与财产风险均处于较低的水平,人员安全风险以中、高风险为主,但极高人员风险的建筑仍占11.70%。 展开更多
关键词 古村镇 火灾风险 frame 单体建筑
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High-precision spot centroid positioning of high-frame-rate short-wave infrared images for satellite laser communication
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作者 FU Peng HE Dao-Gang +1 位作者 LIU Jun WANG Yue-Ming 《红外与毫米波学报》 北大核心 2025年第1期66-77,共12页
The accuracy of spot centroid positioning has a significant impact on the tracking accuracy of the system and the stability of the laser link construction.In satellite laser communication systems,the use of short-wave... The accuracy of spot centroid positioning has a significant impact on the tracking accuracy of the system and the stability of the laser link construction.In satellite laser communication systems,the use of short-wave infrared wavelengths as beacon light can reduce atmospheric absorption and signal attenuation.However,there are strong non-uniformity and blind pixels in the short-wave infrared image,which makes the image distorted and leads to the decrease of spot centroid positioning accuracy.Therefore,the high-precision localization of the spot centroid of the short-wave infrared images is of great research significance.A high-precision spot centroid positioning model for short-wave infrared is proposed to correct for non-uniformity and blind pixels in short-wave infrared images and quantify the localization errors caused by the two,further model-based localization error simulations are performed,and a novel spot centroid positioning payload for satellite laser communications has been designed using the latest 640×512 planar array InGaAs shortwave infrared detector.The experimental results show that the non-uniformity of the corrected image is reduced from 7%to 0.6%,the blind pixels rejection rate reaches 100%,the frame rate can be up to 2000 Hz,and the spot centroid localization accuracy is as high as 0.1 pixel point,which realizes high-precision spot centroid localization of high-frame-frequency short-wave infrared images. 展开更多
关键词 satellite laser communication spot centroid positioning short-wave infrared high frame rate NONUNIFORMITY
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Frames of Fortune
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作者 WANG RUYING 《ChinAfrica》 2025年第9期28-30,共3页
Stepping out of Danyang Railway Station,the large sign reading“China Danyang Optical City”immediately comes into view across the road.Inside the bustling marketplace,a dazzling array of eyeglass frames and lenses is... Stepping out of Danyang Railway Station,the large sign reading“China Danyang Optical City”immediately comes into view across the road.Inside the bustling marketplace,a dazzling array of eyeglass frames and lenses is neatly displayed in rows of shops,attracting consumers from across the country. 展开更多
关键词 FORTUNE eyeglass frames eyeglass lenses CONSUMERS SHOPS frameS MARKETPLACE
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Group frames via magic states with applications to SIC-POVMs and MUBs
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作者 Lingxuan Feng Shunlong Luo 《Communications in Theoretical Physics》 2025年第1期41-53,共13页
We connect magic(non-stabilizer)states,symmetric informationally complete positive operator valued measures(SIC-POVMs),and mutually unbiased bases(MUBs)in the context of group frames,and study their interplay.Magic st... We connect magic(non-stabilizer)states,symmetric informationally complete positive operator valued measures(SIC-POVMs),and mutually unbiased bases(MUBs)in the context of group frames,and study their interplay.Magic states are quantum resources in the stabilizer formalism of quantum computation.SIC-POVMs and MUBs are fundamental structures in quantum information theory with many applications in quantum foundations,quantum state tomography,and quantum cryptography,etc.In this work,we study group frames constructed from some prominent magic states,and further investigate their applications.Our method exploits the orbit of discrete Heisenberg-Weyl group acting on an initial fiducial state.We quantify the distance of the group frames from SIC-POVMs and MUBs,respectively.As a simple corollary,we reproduce a complete family of MUBs of any prime dimensional system by introducing the concept of MUB fiducial states,analogous to the well-known SIC-POVM fiducial states.We present an intuitive and direct construction of MUB fiducial states via quantum T-gates,and demonstrate that for the qubit system,there are twelve MUB fiducial states,which coincide with the H-type magic states.We compare MUB fiducial states and SIC-POVM fiducial states from the perspective of magic resource for stabilizer quantum computation.We further pose the challenging issue of identifying all MUB fiducial states in general dimensions. 展开更多
关键词 Group frames magic states MUBs SIC-POVMs quantum T-gates
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Lightweight design and manufacture of die casting magnesium alloy seat frame
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作者 Jian Yang Kangle Wang +3 位作者 Qin Yang Jinsheng Zhang Tiegang Hu Bo Liu 《Journal of Magnesium and Alloys》 2025年第10期4817-4824,共8页
This study presents the development of a Magnesium Alloy Seat Frame(MASF),supported by case studies from automotive original equipment manufacturers.The process covers integrated design,simulation,manufacturing,and te... This study presents the development of a Magnesium Alloy Seat Frame(MASF),supported by case studies from automotive original equipment manufacturers.The process covers integrated design,simulation,manufacturing,and testing,aiming to boost industry confidence in Mg alloy applications.A novel structural design is developed that integrates the headrest with the backrest,achieving a balance between lightweight performance and safety.Structural optimization is guided by stress–strain simulations under diverse conditions within a complete forward development process.Casting simulations are conducted to analyze process characteristics,resulting in a verified MASF yield rate exceeding 90%.The final 9.88 kg MASF represents a 24.6%(3.23 kg)weight reduction versus a steel seat.This research contributes to advancements in defect control technology for large die casting magnesium alloy parts and has broad implications for their application in automotive manufacturing. 展开更多
关键词 MAGNESIUM Seat frame Forward design Die casting Lightweighting
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Lightweight Design of a Certain Type of Dump Truck Frame
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作者 Chuanqi LI Jian ZOU +2 位作者 Yongjie LI Yingwen REN Xinxing YU 《Mechanical Engineering Science》 2025年第1期12-19,共8页
With the rapid growth of China's economic strength,the demand and market share are also constantly increasing.The number ofcars is rapidly increasing,and a large amount of fuel is consumed as a result.The massive ... With the rapid growth of China's economic strength,the demand and market share are also constantly increasing.The number ofcars is rapidly increasing,and a large amount of fuel is consumed as a result.The massive release of vehicle exhaust seriously damages the natural environment,and the environmental crisis is becoming increasingly serious.This article follows the principles of improving fuel efficiency,reducing emissions,andenhancing vehicle performance.Using NX 12.0 software,a three-dimensional model of a certain type of dump truck frame is constructed based on actual parameters.ANSYS Workbench is used to simplify the geometric model,mesh division,and material definition,and a finite element model is constructed.Obtain the structural performance and natural vibration characteristics of the original chassis under four typical working conditions:bending,torsion,lifting,and unloading,through static analysis and modal analysis.On this basis,the dimensions of the components that bear less load on the original frame were optimized,and the topology of the second crossbeam and rear end corner of the subframe that bear less load on the original frame was optimized to obtain a new frame.The new frame of the dump truck underwent secondary static analysis and modal analysis,and it was found that the weight of the new frame decreased by 41.03 kg,successfully reducing the weight of the frame by 4.38%,improving the vehicle's handling and stability,and extending its service life. 展开更多
关键词 Dump truck frame Lightweight design static analysis
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Enhancing some separability criteria via equiangular tight frames
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作者 Liang Tang Fan Wu 《Communications in Theoretical Physics》 2025年第4期45-54,共10页
Improvement of the detection ability of quantum entanglement is one of the essential tasks in quantum computing and quantum information.Finite tight frames play a fundamental role in a wide variety of areas and,genera... Improvement of the detection ability of quantum entanglement is one of the essential tasks in quantum computing and quantum information.Finite tight frames play a fundamental role in a wide variety of areas and,generally,each application requires a specific class of frames and is closely related to quantum measurement.It is worth noting that a maximal set of complex equiangular vectors is closely related to a symmetric informationally complete measurement.Hence,our goal in this work is to propose a series of separability criteria assigned to a finite tight frame and some well-known inequalities in different quantum systems,respectively.In addition,some tighter criteria to detect entanglement for many-body quantum states are presented in arbitrary dimensions.Finally,the effectiveness of the proposed entanglement detection criteria is illustrated through some detailed examples. 展开更多
关键词 entanglement detection separability criterion bipartite systems finite tight frames
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Research Progress on Earthquake Collapse Resistance of Reinforced Concrete Frame Structures
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作者 Haibing Liu Junqi Lin Jinlong Liu 《Journal of Architectural Research and Development》 2025年第1期52-57,共6页
With the development of modern society,people put forward higher requirements for building safety,which makes the construction project face new challenges.Reinforced concrete frame structure as a common engineering ty... With the development of modern society,people put forward higher requirements for building safety,which makes the construction project face new challenges.Reinforced concrete frame structure as a common engineering type,although the construction technology has been relatively mature,but its earthquake collapse ability still needs to be strengthened.This paper analyzes the specific factors that affect the seismic collapse ability of reinforced concrete frame structure,summarizes the previous research results,and puts forward innovative application of fiber-reinforced polymer(FRP)composite materials,play the role of smart materials,improve the isolation and energy dissipation devices,etc.,to promote the continuous optimization of reinforced concrete frame structure design,and show better seismic performance. 展开更多
关键词 Reinforced concrete frame structure Seismic performance COLLAPSE Research status
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Minimum Number of Load Increments in Second-Order Elastic Analyses of Steel Frames
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作者 Nadine Faramawi Barry T.Rosson 《Journal of Civil Engineering and Architecture》 2025年第11期523-527,共5页
A relationship was discovered between the amplification factor and the number of load increments that are needed to limit the relative error to one percent in second-order elastic analyses with a predictor-corrector s... A relationship was discovered between the amplification factor and the number of load increments that are needed to limit the relative error to one percent in second-order elastic analyses with a predictor-corrector solution scheme.Previous research by the authors proposed a design equation to determine the required minimum number of load increments based on an evaluation of the elastic critical buckling load ratio.Further research has shown that an approximate amplification factor equation that is based on the B2 multiplier equation produces similar results when the amplification factor is less than approximately four.Eleven moment frames are used to verify the use of the new approximate amplification factor in the proposed design equation. 展开更多
关键词 Nonlinear geometric analysis amplification factor load increment structural frame
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Comparative Study of Railway Frame Bridges Designed According to the Chinese and AREMA Codes
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作者 Jia Chenjun Zeng Chunqing +1 位作者 Qu Zixin Zhang Zhongbo 《铁道技术标准(中英文)》 2025年第5期96-104,共9页
Based on the Etihad Railway Station Project,this study selects a single-span frame bridge with a clear span of 7.3 meters as the research object.A comprehensive structural design process was conducted following the AR... Based on the Etihad Railway Station Project,this study selects a single-span frame bridge with a clear span of 7.3 meters as the research object.A comprehensive structural design process was conducted following the AREMA(2023),Manual for Railway Engineering-Volume 2-Structures,with systematic comparisons of techno-economic differences between the Chinese and American codes through recalculation verification and equivalent-precision design methods.The findings reveal:Recalculation using the Chinese code for identical structural dimensions and reinforcement layouts demonstrates that AREMA code exhibits greater conservatism in both strength requirements and crack control;Under equivalent precision design principles,the Chinese code solution reduces reinforcement by 4.128 t tons and a 19.5%reduction in reinforcement at critical sections compared to the AREMA code,indicating slightly reduced economic efficiency of the AREMA code.This research provides quantitative references for standardized design and specification integration in cross-border railway engineering projects. 展开更多
关键词 comparative study AREMA frame bridge cooper E80 safety factor
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Modal Analysis and Test of Feeding Frame of Large Quartz Crucible
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作者 MA Xianglin SUN Xikai +1 位作者 LI Yao SHEN Yimin 《International Journal of Plant Engineering and Management》 2025年第4期193-209,共17页
In view of the demand for intelligent upgrading of quartz crucible manufacturing equipment,this study proposes a design scheme of large-scale quartz crucible feeding frame system with innovative structure,and analyzes... In view of the demand for intelligent upgrading of quartz crucible manufacturing equipment,this study proposes a design scheme of large-scale quartz crucible feeding frame system with innovative structure,and analyzes the vibration characteristics of this structure in view of the large vibration and instability during operation.In order to study the relationship between the operating vibration and the natural frequency and avoid resonance,the calculated mode was analyzed via ANSYS Workbench,and the experimental mode results were obtained by using percussion test and compared with the calculated mode.It is concluded that the natural frequencies of the first six orders of the large quartz crucible feeding frame are between 5.13 and 23.29,and the main deformation is distributed at the end of the turning mechanism.The analysis results show that the first-order natural frequency of the system has a safety margin of 1.55 times comparing with the working frequency of the drive motor(12 Hz),which effectively avoids the risk of resonance.The feeding frame adopts a double-column truss composite structure,and the layout of the specially designed stiffener network and high-precision guide rails ensures the lightweight structure and significantly improves the dynamic stability of the system.The practical effect of the large-scale quartz crucible feeding frame shows that the structural design is successful,and has reference significance for the structural design of the same type of automatic manufacturing equipment. 展开更多
关键词 quartz crucible feeding frame modal analysis modal test
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Seismic design of variable cross-section damped steel support frame for post equipment
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作者 Yang Zhenyu Ma Yuhong +2 位作者 Zhao Guifeng Feng Zhiwei Fu Mingyang 《Earthquake Engineering and Engineering Vibration》 2025年第1期155-167,共13页
High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped ... High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped steel support frame(VCDFS)with viscous dampers to reduce seismic responses of both tall and low-rise electrical equipment.The VCDFS contains a trapezoidal damper layer to generate rocking motions,enabling the diagonal viscous dampers to dissipate seismic inputs.A theoretical model of post equipment with VCDFS is established,and an optimal design procedure is proposed.The analysis shows that the remaining static stiffness ratio λ_(k) is the key parameter that determines the effectiveness of the VCDFS.The VCDFS reduces the average displacement and stress response of a post insulator by 39.4%and 44.6%,respectively,together with a significant decrease in the dynamic amplification factor.Therefore,it is recommended to use the VCDFS instead of the conventional latticed-steel frame in earthquake zones. 展开更多
关键词 electrical post equipment steel support frame passive control seismic performance upgrading
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Niupai Machinery&Elecronics:Bring a variety of shedding devices and heald frame equipment to the exhibition
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《China Textile》 2025年第5期50-50,共1页
Jiangsu Niupai Machinery&Elecronics Co,ltd.is National Specialized and New"Little Giant"Enterprise,National High&New Technological Enterprise,Jiangsu Provincial Research Center of Loom Shedding Engin... Jiangsu Niupai Machinery&Elecronics Co,ltd.is National Specialized and New"Little Giant"Enterprise,National High&New Technological Enterprise,Jiangsu Provincial Research Center of Loom Shedding Engineering Technology and Jiangsu Provincial Enterprise Technology Center.The company has obtained SGS-certified ISO9001 quality management system,a globally recognized standard.Niupai specializes in the R&D and manufacturing of cam shedding device,dobby shedding device,jacquard shedding device and heald frames for water-jet looms,air-jet looms as well as rapier looms. 展开更多
关键词 national specialized newlittle giant enterprise quality management loom shedding engineering technology cam shedding devicedobby shedding devicejacquard shedding device loom shedding engineering heald frame equipment national high new technological enterprise heald frames
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Enhancement of rust leaching by frame blades and its mechanisms
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作者 Lei ZHOU Qiu-yue ZHAO +2 位作者 Guo-zhi LV Zhi-he DOU Ting-an ZHANG 《Transactions of Nonferrous Metals Society of China》 2025年第11期3949-3960,共12页
Frame blades were used to replace traditional propeller blades to enhance the leaching step efficiency of Becher process.A combined approach of leaching,electrochemical experiments,and numerical simulations was employ... Frame blades were used to replace traditional propeller blades to enhance the leaching step efficiency of Becher process.A combined approach of leaching,electrochemical experiments,and numerical simulations was employed.Results demonstrate a significant improvement in leaching efficiency using frame blades compared to propellers,reducing reaction time from 15 to 10 h.Even at a stirring speed of 300 r/min,frame blades perform better than propellers at 500 r/min.Kinetics analysis indicates that the leaching process is controlled by surface chemical reactions.CFD-PBM simulations reveal that frame blades at 300 r/min generate larger bubbles and higher turbulent kinetic energy than propeller blades at 500 r/min.Frame blades enhance leaching efficiency by refining bubble size to improve oxygen mass transfer and by increasing turbulent kinetic energy for better mixing. 展开更多
关键词 Becher process CFD-PBM method frame blade reduced ilmenite synthetic rutile rust leaching
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Physical and numerical modeling of a framed anti-sliding structure for a mountainous railway line
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作者 QIU Ruizhe LIU Kaiwen +3 位作者 YANG Zhixiang MA Chiyuan XIAO Jian SU Qian 《Journal of Southeast University(English Edition)》 2025年第1期12-19,共8页
To ensure the operational safety of railways in the landslide-prone areas of mountainous regions,a large-scale model test and numerical simulation were conducted to study the bending moment distribution,internal force... To ensure the operational safety of railways in the landslide-prone areas of mountainous regions,a large-scale model test and numerical simulation were conducted to study the bending moment distribution,internal force distribution,deformation development,and crack propagation characteristics of a framed anti-sliding structure(FAS)under landslide thrust up to the point of failure.Results show that the maximum bending moment and its increase rate in the fore pile are greater than those in the rear pile,with the maximum bending moment of the fore pile approximately 1.1 times that of the rear pile.When the FAS fails,the displacement at the top of the fore pile is significantly greater,about 1.27 times that of the rear pile in the experiment.Major cracks develop at locations corresponding to the peak bending moments.Small transverse cracks initially appear on the upper surface at the intersection between the primary beam and rear pile and then spread to the side of the structure.At the failure stage,major cracks are observed at the pil-beam intersections and near the anchor points.Strengthening flexural stiffness at intersections where major cracks occur can improve the overall thrust-deformation coordination of the FAS,thereby maximizing its performance. 展开更多
关键词 mountainous railway SLOPE framed anti-sliding structure model test finite element modeling mechanical responses
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Evaluating Euler pole parameters for the north American terrestrial reference frame of 2022
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作者 Mohammad Ali Goudarzi 《Geodesy and Geodynamics》 2025年第6期681-692,共12页
Euler Pole Parameters(EPPs)were estimated for the new plate-fixed North American Terrestrial Reference Frame of 2022(NATRF2022)based on the spherical model of Earth using different sets of continuously operating GPS(c... Euler Pole Parameters(EPPs)were estimated for the new plate-fixed North American Terrestrial Reference Frame of 2022(NATRF2022)based on the spherical model of Earth using different sets of continuously operating GPS(cGPS)station velocities.Two objectives were considered in this research:(1)the possibility of using the cGPS stations located in the areas affected by the Glacial Isostatic Adjustment(GIA),and(2)minimizing the reference frame velocities across the entire continent for conventional uses such as surveying and mapping.A key consideration in this analysis is accounting for the impact of the ongoing GIA on the horizontal velocities.The predicted horizontal velocities from the ICE-6G model were used to remove the GIA effect from the velocity field to mitigate such biases.As a proof of concept,different data sets from a large set of cGPS station velocities were selected,and EPPs were estimated for all these sets of stations with and without removing the GIA effect and estimating or not estimating the Plate Translation Rate(PTR).Considering the WRMS as the criterion for showing goodness of fit,the results show that accounting for the GIA effect reduces the NATRF2022 velocities.Using the same velocity dataset,the PTR was estimated along with the conventional Euler's rotation parameters,and it was shown that estimating the PTR term can further reduce the NATRF2022 velocities. 展开更多
关键词 Reference frame North America tectonic plate Euler pole parameters Plate translation rate NATRF2022
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Corrigendum to“Meta databases of steel frame buildings for surrogate modelling and machine learning-based feature importance analysis”[Journal of Resilient Cities and Structures Volume 3 Issue 1(2024)20-43]
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作者 Delbaz Samadian Jawad Fayaz +2 位作者 Imrose B.Muhit Annalisa Occhipinti Nashwan Dawood 《Resilient Cities and Structures》 2025年第1期124-124,共1页
The authors regret that the original publication of this paper did not include Jawad Fayaz as a co-author.After further discussions and a thorough review of the research contributions,it was agreed that his significan... The authors regret that the original publication of this paper did not include Jawad Fayaz as a co-author.After further discussions and a thorough review of the research contributions,it was agreed that his significant contributions to the foundational aspects of the research warranted recognition,and he has now been added as a co-author. 展开更多
关键词 machine learning meta databases jawad fayaz surrogate modelling feature importance analysis steel frame buildings
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全户内变电站装配式钢框架部分隔震结构体系振动台试验
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作者 郭小农 陈劭臻 +2 位作者 罗金辉 方瑜 吴祖咸 《同济大学学报(自然科学版)》 北大核心 2026年第2期182-191,263,共11页
针对既有非隔震全户内变电站中楼面设备加速度超限的问题,提出在楼板与设备之间增设隔震支座的部分隔震改造策略。基于此,设计并开展了全户内变电站装配式钢框架结构的振动台试验,包括基底固定体系(FBS)、基底隔震体系(BIS)以及部分隔... 针对既有非隔震全户内变电站中楼面设备加速度超限的问题,提出在楼板与设备之间增设隔震支座的部分隔震改造策略。基于此,设计并开展了全户内变电站装配式钢框架结构的振动台试验,包括基底固定体系(FBS)、基底隔震体系(BIS)以及部分隔震体系(PIS)。其中,根据所采用隔震支座的类型,BIS又分为天然橡胶支座(BIS-LNR)和铅芯橡胶支座(BIS-LR)2种型式。试验结果表明,FBS的最大设备加速度达到1.42g,远超限值0.6g,而BIS-LNR、BIS-LR和PIS分别将设备加速度平均降低了87%、69%和77%。在结构响应方面,BIS的最大层间位移角仅为FBS的38%;PIS与FBS相近,两者最大层间位移角均远小于限值1/50。因此,将既有非隔震全户内变电站改造为PIS,能实现结构与设备响应的双重控制目标。 展开更多
关键词 部分隔震 基底隔震 钢框架结构 振动台试验
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锈蚀RC框架节点核心区剪切恢复力模型
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作者 郑山锁 刘立国 +3 位作者 董立国 杨松 李健 丛峻 《建筑科学与工程学报》 北大核心 2026年第1期162-172,共11页
为满足一般大气条件下在役RC框架结构抗震分析的需求,对12榀RC框架节点进行了人工加速腐蚀和拟静力加载试验,探究了锈蚀水平、轴压比变化对节点破坏模式、滞回性能以及核心区抗剪性能的影响;基于试验结果的多参数回归分析,建立了锈蚀RC... 为满足一般大气条件下在役RC框架结构抗震分析的需求,对12榀RC框架节点进行了人工加速腐蚀和拟静力加载试验,探究了锈蚀水平、轴压比变化对节点破坏模式、滞回性能以及核心区抗剪性能的影响;基于试验结果的多参数回归分析,建立了锈蚀RC节点核心区的剪切恢复力模型,并在OpenSEES软件中利用Joint2D和纤维梁柱单元建立了锈蚀RC节点的组合体数值模型。结果表明:锈蚀RC节点的破坏模式均为节点核心区的剪切破坏,锈蚀程度与轴压比的增大会削弱RC节点及其核心区的承载能力与变形能力,导致抗震性能发生劣化;提出的剪切恢复力模型能够较全面反映不同锈蚀程度和不同轴压比RC节点核心区的剪切滞回特性;建立的锈蚀RC节点组合体数值模型的荷载模拟相对误差基本不超过10%,变形模拟相对误差基本不超过20%,最终破坏时的累积耗能相对误差也基本控制在30%以内;基于锈蚀RC节点核心区剪切恢复力模型所建立的节点组合体数值模型能够较准确模拟往复加载作用下锈蚀RC节点的滞回性能,可用于一般大气环境下RC节点及框架的抗震分析评估。 展开更多
关键词 锈蚀RC框架节点 剪切恢复力模型 抗震性能 OPENSEES
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基于关键帧图像特征的视频分类研究
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作者 张建光 李永霞 刘浩泽 《衡水学院学报》 2026年第1期7-12,共6页
针对视频分类问题,首先对视频进行灰度化、高斯去噪和边缘检测处理,然后提取关键帧,接着对选择的关键帧进行图像特征提取,最后进行语义分类。为了增加关键帧的语义完整性,进一步提出了基于关键帧融合的方法,该方法可以有效避免背景关键... 针对视频分类问题,首先对视频进行灰度化、高斯去噪和边缘检测处理,然后提取关键帧,接着对选择的关键帧进行图像特征提取,最后进行语义分类。为了增加关键帧的语义完整性,进一步提出了基于关键帧融合的方法,该方法可以有效避免背景关键帧被选择。为了验证方法的有效性,利用C3D进行深度视频特征提取,同时利用HOG、InceptionV3和ViT分别对关键帧进行传统图像特征和深度图像特征提取,并使用KNN分类器进行数据分类。在KTH和UCF11两个数据集上开展实验,实验结果表明,所提出的方法可以使视频帧更有效地表示视频的语义内容,提高了视频分类任务的准确性,降低了空间需求。 展开更多
关键词 视频分类 图像特征 关键帧
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