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Rapid Seismic Damage Quantification for Reinforced Concrete Frames using Minimal Strain Inputs and Neural Networks Trained via Pushover Analysis
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作者 Mohammadreza Vafaei Sophia C.Alih Abdirahman Abdulkadir 《Computer Modeling in Engineering & Sciences》 2026年第3期509-537,共29页
Rapid quantification of seismic-induced damage immediately following an earthquake is critical for determining whether a structure is safe for continued occupation or requires evacuation.This study proposes a novel da... Rapid quantification of seismic-induced damage immediately following an earthquake is critical for determining whether a structure is safe for continued occupation or requires evacuation.This study proposes a novel damage identification method that utilizes limited strain data points,significantly reducing installation,maintenance,and data analysis costs compared to traditional distributed sensor networks.The approach integrates finite element(FE)modeling to generate capacity curves through pushover analysis,incorporates noise-augmented datasets for Artificial Neural Network(ANN)training,and classifies structural conditions into four damage levels:Operational(OP),Immediate Occupancy(IO),Life Safety(LS),and Collapse Prevention(CP).To evaluate the method’s accuracy and efficiency,it was applied to two reinforced concrete(RC)frames;a single-story frame tested experimentally under cyclic loading and a three-story frame analyzed under various lateral load patterns.Strain data from selected beam and column ends were used as ANN inputs,while the corresponding damage classes served as outputs.Confusion matrix results demonstrated high true positive rates(>85%for the single-story and>90%for the three-story frame),even with a reduced number of sensors.The model also exhibited strong robustness to White Gaussian Noise(SNR=2.5-5 dB)and generalized effectively to nonlinear time-history analyses under scaled ground motions(PGA=0.1-1.0 g).Feature selection using the MRMR and ANOVA algorithms further enhanced computational efficiency.Overall,the proposed ANN-based framework has strong potential for real-time structural health monitoring applications. 展开更多
关键词 Damage detection SEISMIC structural health monitoring reinforced concrete frame neural networks strain data
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Separability criteria and entanglement witnesses from mutually unbiased equiangular tight frames
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作者 Alexey E Rastegin 《Communications in Theoretical Physics》 2026年第2期35-43,共9页
Methods of quantum information processing often appear in terms of specially selected states.For example,mutually unbiased bases(MUBs)and symmetric informationally complete measurements are widely applied.Finite frame... Methods of quantum information processing often appear in terms of specially selected states.For example,mutually unbiased bases(MUBs)and symmetric informationally complete measurements are widely applied.Finite frames have found use in many areas including quantum information.Due to its specific inner structure,a single equiangular tight frame(ETF)allows one to formulate criteria to detect non-classical correlations.This study aims to approach entanglement detection with the use of mutually unbiased ETFs.Such frames are an interesting generalization of widely recognized MUBs.It still uses rank-one operators,but the number of outcomes can exceed the dimensionality.Several approaches are considered including separability criteria and entanglement witnesses.Separability criteria for multipartite systems are finally obtained. 展开更多
关键词 equiangular tight frames mutual unbiasedness separable states entanglement witnesses
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Diagnosing Organizational Bottlenecks in Student Software Projects with Extended Problem Frames
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作者 Zicheng Huang Hongbin Xiao Zhi Li 《计算机教育》 2026年第3期210-219,共10页
In educational settings,instructors often lead students through hands-on software projects,sometimes engaging two different schools or departments.How can such collaborations be made more efficient,and how can student... In educational settings,instructors often lead students through hands-on software projects,sometimes engaging two different schools or departments.How can such collaborations be made more efficient,and how can students truly experience the importance of teamwork and the impact of organizational structure on project complexity?To answer these questions,we introduce the requirement-driven organization structure(R-DOS)approach,which tightly couples software requirements with the actual development process.By extending problem-frames modeling and focusing on requirements,R-DOS allows educators and students to(1)diagnose structural flaws early,(2)prescribe role-level and communication fixes,and(3)observe-in real time-how poor structure can derail a project while good structure accelerates learning and delivery. 展开更多
关键词 Requirements engineering Organization structure Problem frames
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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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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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SOME RESULTS ON CONTROLLED FRAMES IN HILBERT SPACES 被引量:4
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作者 Kamran MUSAZADEH Hassan KHANDANI 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期655-665,共11页
We use two appropriate bounded invertible operators to define a controlled frame with optimal frame bounds. We characterize those operators that produces Parseval controlled frames also we state a way to construct nea... We use two appropriate bounded invertible operators to define a controlled frame with optimal frame bounds. We characterize those operators that produces Parseval controlled frames also we state a way to construct nearly Parseval controlled frames. We intro- duce a new perturbation of controlled frames to obtain new frames from a given one. Also we reduce the distance of frames by appropriate operators and produce nearly dual frames from two given frames which are not dual frames for each other. 展开更多
关键词 frameS Parseval frames dual frames controlled frames reconstruction formula PERTURBATION
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High-precision spot centroid positioning of high-frame-rate short-wave infrared images for satellite laser communication 被引量:1
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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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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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Fusion-Riesz frame in Hilbert space
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作者 LI Xue-bin YANG Shou-zhi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第3期339-352,共14页
Fusion-Riesz frame (Riesz frame of subspace) whose all subsets are fusion frame sequences with the same bounds is a special fusion frame. It is also considered a generalization of Riesz frame since it shares some impo... Fusion-Riesz frame (Riesz frame of subspace) whose all subsets are fusion frame sequences with the same bounds is a special fusion frame. It is also considered a generalization of Riesz frame since it shares some important properties of Riesz frame. In this paper, we show a part of these properties of fusion-Riesz frame and the new results about the stabilities of fusion-Riesz frames under operator perturbation (simple named operator perturbation of fusion-Riesz frames). Moreover, we also compare the operator perturbation of fusion-Riesz frame with that of fusion frame, fusion-Riesz basis (also called Riesz decomposition or Riesz fusion basis) and exact fusion frame. 展开更多
关键词 fusion-Riesz frame Riesz frame of subspace Riesz frame exact fusion frame
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ON NECESSARY AND SUFFICIENT CONDITIONS FOR DUALS OF WAVELET FRAMES
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作者 Zhang Zeyin Wang Jianzhong 《Acta Mathematica Scientia》 SCIE CSCD 1995年第1期6-14,共9页
This paper is concerned with the characterization of the duals of wavelet frames of L(2)(R).The sufficient and necessary conditions for them are obtained.
关键词 Waveiet anglysis frameS Dual frames Affine frames Tight frames.
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Lightweight Multi-Layered Encryption and Steganography Model for Protecting Secret Messages in MPEG Video Frames
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作者 Sara H.Elsayed Rodaina Abdelsalam +2 位作者 Mahmoud A.Ismail Shoman Raed Alotaibi Omar Reyad 《Computers, Materials & Continua》 2025年第12期4995-5013,共19页
Ensuring the secure transmission of secret messages,particularly through video—one of the most widely used media formats—is a critical challenge in the field of information security.Relying on a single-layered secur... Ensuring the secure transmission of secret messages,particularly through video—one of the most widely used media formats—is a critical challenge in the field of information security.Relying on a single-layered security approach is often insufficient for safeguarding sensitive data.This study proposes a triple-lightweight cryptographic and steganographic model that integrates the Hill Cipher Technique(HCT),Rotation Left Digits(RLD),and Discrete Wavelet Transform(DWT)to embed secret messages within video frames securely.The approach begins with encrypting the secret text using a private key matrix(PK^(1))of size 2×2 up to 6×6 via HCT.A second encryption layer is applied using a dynamic private key(PK2)derived from the RGB pixel values of the video frame,resulting in a rotated cipher.The doubly encrypted message is then embedded into the video frames using the DWT method.Upon transmission,the concealed message is extracted using inverse DWT and decrypted in two steps—first with PK2 and then with the inverse of PK^(1).Experiments conducted using MPEG video sequences and message lengths ranging from 10 to 300 bytes demonstrate strong performance in terms of Mean Square Error(MSE),Peak Signal-to-Noise Ratio(PSNR),and Correlation Coefficient(CC)between original and encrypted messages.The similarity between original and stego frames is further validated using Structural Similarity Index(SSIM),Mean Absolute Error(MAE),Number of Pixel Change Rate(NPCR),and Unified Average Changing Intensity(UACI).Results confirm that utilizing video frames to generate PK2 offers superior security compared to static key images.Moreover,the indistinguishability between original and stego frames highlights the method’s robustness against visual and statistical attacks. 展开更多
关键词 Lightweight encryption stego frame HCT RLD DWT SSIM MAE NPCR UACI
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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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G-Frame Representation and Invertibility of G-Bessel Multipliers
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作者 A.ABDOLLAHI E.RAHIMI 《Journal of Mathematical Research with Applications》 CSCD 2013年第4期392-402,共11页
In this paper we show that every g-frame for an infinite dimensional Hilbert space H can be written as a sum of three g-orthonormal bases for H. Also, we prove that every g-frame can be represented as a linear combina... In this paper we show that every g-frame for an infinite dimensional Hilbert space H can be written as a sum of three g-orthonormal bases for H. Also, we prove that every g-frame can be represented as a linear combination of two g-orthonormal bases if and only if it is a g-Riesz basis. Further, we show each g-Bessel multiplier is a Bessel multiplier and investigate the inversion of g-frame multipliers. Finally, we introduce the concept of controlled g-frames and weighted g-frames and show that the sequence induced by each controlled g-frame (resp., weighted g-frame) is a controlled frame (resp., weighted frame). 展开更多
关键词 g-frames g-orthonormal basis controlled g-frames weighted g-frames g-frame multipliers.
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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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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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Impact dynamics of debris flow with entrained material on frame structure
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作者 LI Bailong WANG Huayan +1 位作者 LI Yanying LI Xiangling 《Journal of Mountain Science》 2025年第12期4523-4539,共17页
To evaluate the dynamic interactions between debris flows,entrained material sources,and infrastructure in the Naojiao Gully watershed of Beijing,and to develop a predictive framework for mitigating geohazard risks th... To evaluate the dynamic interactions between debris flows,entrained material sources,and infrastructure in the Naojiao Gully watershed of Beijing,and to develop a predictive framework for mitigating geohazard risks through energy-based strategies,debris flow dynamics are investigated,a coupled SPH-DEM-FEM multiscale model integrating fluid dynamics(SPH),granular mechanics(DEM),and structural mechanics(FEM)is developed to simulate debris flow propagation,material source behavior,and frame structure responses,and to capture cross-scale failure mechanisms.Key findings include the identification of a critical flow velocity threshold of 12 m/s,beyond which solid-phase kinetic energy dominates,inducing 60%-75%capacity loss in central columns via through-cracking.Furthermore,a novel compound failure criterion is proposed based on the solid-liquid energy proportion.The model achieves a boulder impact force prediction error of only 5.47%,significantly outperforming empirical methods in cross-scale accuracy.An optimized 0.3 m layered configuration experimentally reduces impact pulse peaks by 57%through directed energy redistribution,thereby shifting mitigation strategies from structural reinforcement to media modulation.These results establish a robust framework for quantifying failure thresholds,enhancing predictive precision,and innovating energy-based mitigation.By bridging multiscale modeling gaps in geohazard analysis,this study provides actionable insights for infrastructure resilience in debris flow-prone regions through energycentric design principles. 展开更多
关键词 SPH-DEM-FEM coupling Source material Dynamic response frame structure
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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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