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Joinery and Structure:Cultural and Technical Comparison between Traditional Wooden Framing Systems in East Asia and Western Europe 被引量:2
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作者 LIU Yan 《Chinese Annals of History of Science and Technology》 2022年第1期89-118,共30页
Traditional wooden joinery is the craft of connecting wood pieces for buildings or producing utensils by utilizing only the geometry of the components and material properties of the wood,without other materials such a... Traditional wooden joinery is the craft of connecting wood pieces for buildings or producing utensils by utilizing only the geometry of the components and material properties of the wood,without other materials such as glue or metal connectors.In its thousands of years of tradition,this construction technique has achieved high accomplishment in both East Asian and European architectural civilizations.Although sharing the same basic principles,joinery techniques vary between regions and cultures,rooted in the geographical environment,available wood species and their material properties,characteristics of craftsmanship,tools,and structural systems.Wood framing systems from China,Japan,and Western Europe are selected for comparison to assess the relationship between wood joinery and other aspects of building technology.The main conclusions include:in East Asia,the building tradition pays great attention to the design and execution of joinery(sunmao榫卯),making it responsible for multiple functions including architectural mechanics and the stability of the entire frame,which leads to a broader role meant by the term“joint”itself,while in Europe joinery is treated as the“node”or literally“joint”of the structure.Although in both East Asia and Europe wooden joinery serves as an aesthetic factor of the structure,its expression in East Asia is subtle,veiled,and restrained,while in Europe it is explicit and direct.The most important lesson we learn from the study of traditional joinery technology is that it should be seen in the context of the building process as a whole,taking into account geographical environment,material resources,craftsmanship,tools,construction methods,structural form,and the structural system. 展开更多
关键词 wooden joint chuandou tailiang sunmao Fachwerk(half-timbering timber framing) traditional Chinese wooden structure traditional Japanese wooden structure traditional European wooden structure post-and-beam construction
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Cognitive Biases in Artificial Intelligence:Susceptibility of a Large Language Model to Framing Effect and Confirmation Bias
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作者 Li Hao Wang You Yang Xueling 《心理科学》 北大核心 2025年第4期892-906,共15页
The rapid advancement of Artificial Intelligence(AI)and Large Language Models(LLMs)has led to their increasing integration into various domains,from text generation and translation to question-answering.However,a crit... The rapid advancement of Artificial Intelligence(AI)and Large Language Models(LLMs)has led to their increasing integration into various domains,from text generation and translation to question-answering.However,a critical question remains:do these sophisticated models,much like humans,exhibit susceptibility to cognitive biases?Understanding the presence and nature of such biases in AI is paramount for assessing their reliability,enhancing their performance,and predicting their societal impact.This research specifically investigates the susceptibility of Google’s Gemini 1.5 Pro and DeepSeek,two prominent LLMs,to framing effects and confirmation bias.The study meticulously designed a series of experimental trials,systematically manipulating information proportions and presentation orders to evaluate these biases.In the framing effect experiment,a genetic testing decision-making scenario was constructed.The proportion of positive and negative information(e.g.,20%,50%,or 80%positive)and their presentation order were varied.The models’inclination towards undergoing genetic testing was recorded.For the confirmation bias experiment,two reports-one positive and one negative-about“RoboTaxi”autonomous vehicles were provided.The proportion of erroneous information within these reports(10%,30%,and 50%)and their presentation order were systematically altered,and the models’support for each report was assessed.The findings demonstrate that both Gemini 1.5 Pro and DeepSeek are susceptible to framing effects.In the genetic testing scenario,their decision-making was primarily influenced by the proportion of positive and negative information presented.When the proportion of positive information was higher,both models showed a greater inclination to recommend or proceed with genetic testing.Conversely,a higher proportion of negative information led to greater caution or a tendency not to recommend the testing.Importantly,the order in which this information was presented did not significantly influence their decisions in the framing effect scenarios.Regarding confirmation bias,the two models exhibited distinct behaviors.Gemini 1.5 Pro did not show an overall preference for either positive or negative reports.However,its judgments were significantly influenced by the order of information presentation,demonstrating a“recency effect,”meaning it tended to support the report presented later.The proportion of erroneous information within the reports had no significant impact on Gemini 1.5 Pro’s decisions.In contrast,DeepSeek exhibited an overall confirmation bias,showing a clear preference for positive reports.Similar to Gemini 1.5 Pro,DeepSeek’s decisions were also significantly affected by the order of information presentation,while the proportion of misinformation had no significant effect.These results reveal human-like cognitive vulnerabilities in advanced LLMs,highlighting critical challenges to their reliability and objectivity in decision-making processes.Gemini 1.5 Pro’s sensitivity to presentation order and DeepSeek’s general preference for positive information,coupled with its sensitivity to order,underscore the need for careful evaluation of potential cognitive biases during the development and application of AI.The study suggests that effective measures are necessary to mitigate these biases and prevent potential negative societal impacts.Future research should include a broader range of models for comparative analysis and explore more complex interactive scenarios to further understand and address these phenomena.The findings contribute significantly to understanding the limitations and capabilities of current AI systems,guiding their responsible development,and anticipating their potential societal implications. 展开更多
关键词 artificial intelligence large language models cognitive bias confirmation bias framing effect
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A Study of National Image Reconstruction in English Translation of Soft News from the Perspective of Framing Narratives: A Case Study of China Daily
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作者 Tianyue Dou 《Journal of Contemporary Educational Research》 2025年第4期135-140,共6页
At present,strengthening China’s international communication capabilities and enhancing China’s global influence have become important tasks.This study selects 60 pieces of soft news from China Daily from March 2023... At present,strengthening China’s international communication capabilities and enhancing China’s global influence have become important tasks.This study selects 60 pieces of soft news from China Daily from March 2023 to February 2024 as research objects and explores China’s national image from the source texts.Then,based on Mona Baker’s narrative theory,it analyzes the translation strategies to reconstruct the image of China,further revealing the regular characteristics of their application.Through translation,the reconstructed national image of China becomes more positive and more acceptable to foreign readers,effectively promoting the dissemination of Chinese stories in the international community.It is significant for promoting international understanding and cooperation,as well as effectively utilizing translation as a tool to enhance China’s national image. 展开更多
关键词 China Daily National image framing narratives Soft news translation
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The Spatiotemporal Construction and Landscape Framing of Cultural Micro-Dramas
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作者 Chen Haiyan Li Yufen 《Contemporary Social Sciences》 2025年第2期1-11,共11页
As an emerging media format with immense growth potential,micro-dramas(MDs)carry the critical mission of inheriting and innovating China’s fine traditional culture in the new era.From the three dimensions of time,spa... As an emerging media format with immense growth potential,micro-dramas(MDs)carry the critical mission of inheriting and innovating China’s fine traditional culture in the new era.From the three dimensions of time,space,and landscape in media geography,the pathways for cultural inheritance and innovation through MDs can be summarized as follows:Temporally,cultural MDs construct cultural narratives from the“past”to the“future;”spatially,they build immersive cultural spaces blending reality and imagination,enhancing viewers’audiovisual experiences;through the interplay of time and space,they create diversified cultural landscapes on new media platforms,revitalize enduring cultural memories and foster a sense of community for the Chinese nation through media innovation. 展开更多
关键词 cultural micro-dramas China’s fine traditional culture sense of community for the Chinese nation spatiotemporal construction landscape framing
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An Integrated Approach for Improved Permeability and Reservoir Quality Prediction in Multiporosity Systems,Tahe Ordovician Naturally Fractured Vuggy Carbonates
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作者 Mahaman Salifou Issoufou Aboubacar Heng Zhang +2 位作者 Boukari Issoufou Ousmane Jie Li Zhongxian Cai 《Journal of Earth Science》 2025年第6期2579-2597,共19页
Carbonates present complex pore systems that strongly influence the physical properties and their interrelationships.This study proposes a new approach to establish pore-type mixing-based permeability transforms by in... Carbonates present complex pore systems that strongly influence the physical properties and their interrelationships.This study proposes a new approach to establish pore-type mixing-based permeability transforms by integrating well-log and core data.We investigate the influence of pore-structure heterogeneity on permeability and velocity through the rock-frame flexibility factors(γ and γ_(μ)),derivable using standard sonic and density logs.We derive permeability transforms,with correlation coefficients,R of 0.8 to 0.9,from core measurements and pore-structure variations-dependent physical parameters,namely the porosity exponent(m),Poisson’s ratio(σ),velocity deviation log(VDL),and velocity ratio(VR).Through extrapolation using log-data,the m-and VDL-based correlations provide significantly better permeability estimates,with the highest accuracy attained with the m-based correlation,whereas the VR-andσ-based correlations lead to permeability overes-timation for high porosities.We plotted log-derived porosity vs.permeability,obtained applying the m-based correlation,to generate consistent porosity-permeability relationships,which account for pore-structure heterogeneity,by sorting the scattering points into distinct groups/trends by considering the variations of pore-structure types and abundance of a specific porosity.For the studied oilfield,three porosity-permeability relationships are identified,with correlation coefficients approaching 0.9,thus validating the approach and supporting its application in petrophysically similar reservoirs. 展开更多
关键词 CARBONATES Tahe Oilfield reservoir quality analysis improved permeability transforms rock-physics modeling self-consistent clustering frame flexibility factors petroleum geology
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Enhancing grid stability and V2G integration by optimizing three-phase bidirectional EV chargers using ANFIS and FPGA-based control systems
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作者 Nagarajan Munusamy Indragandhi Vairavasundaram 《Global Energy Interconnection》 2025年第6期1047-1061,共15页
State this study looks at how well a three-phase bidirectional converter works for Vehicle-to-Grid(V2G)services by using both Adaptive Neuro-Fuzzy Inference System(ANFIS)and Proportional-Integral(PI)controllers.When c... State this study looks at how well a three-phase bidirectional converter works for Vehicle-to-Grid(V2G)services by using both Adaptive Neuro-Fuzzy Inference System(ANFIS)and Proportional-Integral(PI)controllers.When compared with ANFIS controllers,traditional controllers such as PI and PID show challenges.They may not sufficiently react to changing conditions or non-linearity’s and use fixed gain values requiring hand tuning.By means of learning,ANFIS controllers can thus dynamically change their parameters,so providing enhanced accuracy and flexibility in real-time control.The main objectives are to control the DC link voltage,lower total harmonic distortion(THD),and lower the errors.The Synchronous Reference Frame(SRF)transformation changes three-phase AC into a two-axis(d-q)system,making it easier to control active and reactive power separately.We developed a thorough Simulink model in MATLAB 2023a to model the bidirectional off-board fast charger at a power level of 60 kW.After validation,a 5-kW hardware prototype was built in the lab.The main platform is an AC-DC converter,followed by a DC-DC converter.A programmable DC power supply,Chroma 62050H-600S,connected to the DC-DC converter,mimics the dynamic characteristics of a battery.The control algorithm,deployed on a Spartan-6 LX9 FPGA,manages both voltage and current,maintaining a stable DC link voltage of 800 V.The results obtained indicate that the ANFIS controller outperforms a conventional PI controller when handling dynamic load variations. 展开更多
关键词 Bidirectional converter Electricvehicle(EV) Adaptive Neuro-Fuzzy Inference system(ANFIS) Synchronous Reference Frame(SRF) Vehicle-to-Grid(V2G)
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Robust frame synchronization method for FDD-LTE systems 被引量:1
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作者 徐文虎 杨广琦 +1 位作者 刘进 洪伟 《Journal of Southeast University(English Edition)》 EI CAS 2011年第3期239-243,共5页
The primary synchronization signal and the secondary synchronization signal are respectively used to fulfill the subframe and frame synchronization in the long term evolution (LTE) systems. Based on the assumption t... The primary synchronization signal and the secondary synchronization signal are respectively used to fulfill the subframe and frame synchronization in the long term evolution (LTE) systems. Based on the assumption that the channel frequency response of the primary synchronization signal symbol is nearly the same as that of the secondary synchronization symbol in frequency division duplex-LTE (FDD-LTE), a new synchronization method is proposed. The frame synchronization success probability is simulated in different wireless channel models and the Mento-Carlo method is used in the simulation. Simulation results show that if the LMMSE channel estimation is adopted, the proposed method is robust at a low signal noise ratio (SNR) scenario and works well when cartier frequency offset and fast Fourier transform (FFT) window timing offset are considered in practical applications. The frame synchronization success probability can still exceed 99% with an SNR of 0 dB when the maximum Doppler shift is very large, which means that this robust frame synchronization method can be applicable in most mobile situations. Simulation results also show that the success probability of the proposed frame synchronization method is higher than that of the method which fulfills the frame synchronization through correlating the received secondary synchronization symbol with local sequences in practical applications. 展开更多
关键词 frame synchronization long term evolution cell search channel estimation
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理想MTL代数
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作者 罗清君 《浙江大学学报(理学版)》 北大核心 2026年第1期39-46,共8页
MTL(Monoidal T-norm based logic)代数是基于左连续三角模的模糊逻辑系统的语义代数,而理想理论是研究MTL代数性质的重要工具。利用加法运算给出了MTL代数理想的等价刻画和生成理想的具体结构。通过定义交、并、蕴涵与补运算,证明了全... MTL(Monoidal T-norm based logic)代数是基于左连续三角模的模糊逻辑系统的语义代数,而理想理论是研究MTL代数性质的重要工具。利用加法运算给出了MTL代数理想的等价刻画和生成理想的具体结构。通过定义交、并、蕴涵与补运算,证明了全体理想之集在集合的包含序下是一个代数格。同时,给出了由全体理想之集构成MTL代数和对合MTL代数的充分且必要条件。 展开更多
关键词 MTL代数 理想 生成理想 FRAME
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Revisiting Nonlinear Modelling Approaches for Existing RC Structures:Lumped vs.Distributed Plasticity
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作者 Hüseyin Bilgin Bredli Plaku 《Structural Durability & Health Monitoring》 2026年第1期70-85,共16页
Nonlinear static procedures are widely adopted in structural engineering practice for seismic performance assessment due to their simplicity and computational efficiency.However,their reliability depends heavily on ho... Nonlinear static procedures are widely adopted in structural engineering practice for seismic performance assessment due to their simplicity and computational efficiency.However,their reliability depends heavily on how the nonlinear behaviour of structural components is represented.The recent earthquakes in Albania(2019)and Türkiye(2023)have underscored the need for accurate assessment techniques,particularly for older reinforced concrete buildings with poor detailing.This study quantifies the discrepancies between default and user-defined component modelling in pushover analysis of pre-modern reinforced concrete structures,analysing two representative low-and mid-rise reinforced concrete frame buildings.The lumped plasticity approach incorporates moment-rotation relationships derived from actual member properties and reinforcement configurations,while the distributed plasticity approach uses software-generated default properties based on modern codes.Results show that the distributed plasticity models systematically overestimate both the strength and the deformation capacity by up to 35%compared to lumped plasticity models,especially in buildings with poor detailing and low concrete strength.These findings demonstrate that default software procedures,widely used in practice but not validated for pre-modern structures,produce dangerously unconservative seismic performance estimates.The study provides quantitative evidence of the critical need for tailored modelling strategies that reflect the actual conditions of the existing building stock. 展开更多
关键词 Reinforced concrete frames seismic assessment pushover analysis lumped plasticity distributed plasticity
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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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toGC:A pipeline to correct gene model for functional excavation of dark GPCRs in Phytophthora sojae
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作者 Min Qiu Chun Yan +6 位作者 Huaibo Li Haiyang Zhao Siqun Tu Yaru Sun Saijiang Yong Ming Wang Yuanchao Wang 《Journal of Integrative Agriculture》 2026年第1期150-156,共7页
The accuracy of genomic annotation is crucial for subsequent functional investigations;however,computational protocols used in high-throughput annotation of open reading frames(ORFs)can introduce inconsistencies.These... The accuracy of genomic annotation is crucial for subsequent functional investigations;however,computational protocols used in high-throughput annotation of open reading frames(ORFs)can introduce inconsistencies.These inconsistencies,which lead to non-uniform extension or truncation of sequence ends,pose challenges for downstream analyses.Existing strategies to rectify these inconsistencies are time-consuming and labor-intensive,lacking specific approaches.To address this gap,we developed to GC,a tool that integrates genomic annotation with RNA-seq datasets to rectify annotation inconsistencies.Using to GC,we achieved an accuracy of nearly 100%accuracy in correcting inconsistencies in published Phytophthora sojae ORFs.We applied this innovative pipeline to the GPCR-bigrams gene family,which was predicted to have 42 members in the P.sojae genome but lacked experimental validation.By employing to GC,we identified 32 GPCR-bigram ORFs with inconsistencies between previous annotations and to GC-corrected sequences.Notably,among these were 5 genes(GPCR-TKL9,GPCR-TKL15,GPCR-PDE3,GPCR-AC3,and GPCR-AC4)showed substantial inconsistencies.Experimental gene annotation confirmed the effectiveness of to GC,as sequences obtained through cloning matched those annotated by to GC.Importantly,we discovered two novel GPCRs(GPCR-AC3 and GPCR-AC4),which were previously mispredicted as a single gene.CRISPR/Cas9-mediated knockout experiments revealed the involvement of GPCR-AC4 but not GPCR-AC3 in oospore production,further confirming their status as two separate genes.In addition to P.sojae,the reliability of the to GC pipeline in Phytophthora capsici and Pythium ultimum further emphasizes the robustness of this pipeline.Our findings highlight the utility of to GC for reliable gene model correction,facilitating investigations into biological functions and offering potential applications in diverse species analyses. 展开更多
关键词 gene model correction TRANSCRIPTOME open reading frames G-protein coupled receptors
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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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Improved spatio-temporal evidence fusion for radar aerial target tactical intention recognition
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作者 HUAI Liangliang ZHANG Xinyu +2 位作者 WU Shuying YUN Peng LI Bo 《Journal of Systems Engineering and Electronics》 2026年第1期148-156,共9页
To address the issue of incorrect fusion results caused by conflicting evidence due to inaccurate evidence and incomplete recognition frameworks in radar airborne target tactical intention recognition,a spatiotemporal... To address the issue of incorrect fusion results caused by conflicting evidence due to inaccurate evidence and incomplete recognition frameworks in radar airborne target tactical intention recognition,a spatiotemporal evidence fusion algorithm is proposed.To resolve the conflict evidence fusion problem caused by inaccurate evidence,the algorithm performs discounting of evidence from both spatial and temporal dimensions.Spatial discounting is influenced by both inter-evidence inconsistency and intra-evidence inconsistency,while temporal discounting is determined by time intervals and information entropy.For the problem of conflicting evidence fusion due to an incomplete recognition framework,an open recognition architecture based on dynamic composite focal elements is proposed.This approach allocates some conflicting information to temporary composite focal elements,avoiding excessive basic probability assignment(BPA)of the empty set after fusion,which can lead to deviations from the actual fusion results.Simulation experiments comparing various methods indicate that the proposed method can effectively improve target intention recognition accuracy and demonstrates good stability. 展开更多
关键词 evidence fusion tactical intention recognition evidence discount open frame of discernment
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Resilient self-centering viscous-based bracing with SMA and friction springs:Multi-objective control of displacement and acceleration-an analytical study
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作者 Navid Rahgozar M.Shahria Alam 《Resilient Cities and Structures》 2026年第1期133-150,共18页
Self-Centering Piston-Based Braced Frames(SC-PBBFs)are designed to curtail structural damage under severe ground motions.The self-centering mechanism in this bracing mitigates structural damage during an earthquake,th... Self-Centering Piston-Based Braced Frames(SC-PBBFs)are designed to curtail structural damage under severe ground motions.The self-centering mechanism in this bracing mitigates structural damage during an earthquake,thereby reducing post-earthquake repair costs and contributing to seismic resilience.However,non-structural components,particularly those sensitive to floor acceleration,remain vulnerable,resulting in prolonged func-tional recovery times.This paper aims to address this limitation by introducing a novel structural archetype,the Self-Centering Viscous-Based Braced Frame(SC-VBBF),which integrates superelastic shape memory alloy(SMA)bars,viscous dampers(VDs),and friction springs(FSs).A streamlined analytical approach relies on the strength decoupling of VD from other components using aλfactor to design SC-VBBFs.To evaluate the effectiveness of the hybrid brace,a set of 4-,8-,and 12-story archetypes equipped with SC-PBBs and SC-VBBFs are simulated in OpenSees and analyzed under various earthquake types,including crustal,subcrustal,and subduction events.The results demonstrate the superior performance of the SC-VBBF withλ≤0.5 system compared to SC-PBBFs in mitigating floor accelerations under design-level earthquakes and improving seismic resilience. 展开更多
关键词 SELF-CENTERING Piston-based braced frame Self-centering viscous-based brace Shape memory alloy Viscous damper Friction spring Seismic analysis Design procedure Acceleration control
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Ultrafast pulse-dilation framing camera and its application for time-resolved X-ray diagnostic 被引量:6
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作者 Hou-Zhi Cai Qiu-Yan Luo +10 位作者 Kai-Xuan Lin Xuan Deng Jun-Kai Liu Kai-Zhi Yang Dong Wang Jia-Jie Chen Jia-Heng Wang Jing-Hua Long Li-Hong Niu Yun-Fei Lei Jin-Yuan Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期101-114,共14页
An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation devi... An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic lenses.The spatial resolution characteristics of the camera were studied both theoretically and experimentally.The results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the camera.Furthermore,the camera was used to detect the X-rays produced by the laser-targeting device.The diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps. 展开更多
关键词 Inertial confinement fusion Plasma diagnostics framing camera Combined lenses Pulse-dilation
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Simulation of spatially coupling dynamic response of train-track time-variant system 被引量:26
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作者 向俊 李德建 曾庆元 《Journal of Central South University of Technology》 2003年第3期226-230,共5页
There exist three problems in the calculation of lateral vibration of the train-track time-variant system athome and abroad and the method to solve them is presented. Spatially coupling vibration analysis model of tra... There exist three problems in the calculation of lateral vibration of the train-track time-variant system athome and abroad and the method to solve them is presented. Spatially coupling vibration analysis model of train-track time-variant system is put forward. Each vehicle is modeled as a multi-body system with 26 degrees of freedomand the action of coupler is also considered. The track structure is modeled as an assembly of track elements with 30degrees of freedom, then the spatially coupling vibration matrix equation of the train-track time-variant system is es-tablished on the basis of the principle of total potential energy with stationary value and the "set-in-right-position"rule. The track vertical geometric irregularity is considered as the excitation source of the vertical vibration of thesystem, and the hunting wave of car bogie frame is taken as the excitation source of lateral vibration of the system.The spatially coupling vibration matrix equation of the system is solved by Wilson-θ direct integration method. Theapproximation of the calculated results to the spot test results demonstrates the feasibility and effectiveness of thepresented analysis method. Finally, some other vibration responses of the system are also obtained. 展开更多
关键词 vibration TRAIN TRACK time-variant system HUNTING wave car BOGIE FRAME excitation source
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Automatic Method for Synchronizing Workpiece Frames in Twin-robot Nondestructive Testing System 被引量:6
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作者 LU Zongxing XU Chunguang +2 位作者 PAN Qinxue MENG Fanwu LI Xinliang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第4期860-868,共9页
The workpiece frames relative to each robot base frame should be known in advance for the proper operation of twin-robot nondestructive testing system. However, when two robots are separated from the workpieces, the t... The workpiece frames relative to each robot base frame should be known in advance for the proper operation of twin-robot nondestructive testing system. However, when two robots are separated from the workpieces, the twin robots cannot reach the same point to complete the process of workpiece frame positioning. Thus, a new method is proposed to solve the problem of coincidence between workpiece frames. Transformation between two robot base frames is initiated by measuring the coordinate values of three non-collinear calibration points. The relationship between the workpiece frame and that of the slave robot base frame is then determined according to the known transformation of two robot base frames, as well as the relationship between the workpiece frame and that of the master robot base frame. Only one robot is required to actually measure the coordinate values of the calibration points on the workpiece. This requirement is beneficial when one of the robots cannot reach and measure the calibration points. The coordinate values of the calibration points are derived by driving the robot hand to the points and recording the values of top center point(TCP) coordinates. The translation and rotation matrices relate either the two robot base frames or the workpiece and master robot. The coordinated are solved using the measured values of the calibration points according to the Cartesian transformation principle. An optimal method is developed based on exponential mapping of Lie algebra to ensure that the rotation matrix is orthogonal. Experimental results show that this method involves fewer steps, offers significant advantages in terms of operation and time-saving. A method used to synchronize workpiece frames in twin-robot system automatically is presented. 展开更多
关键词 twin-robot system workpiece frame coordinate transformation matrix orthogonal Lie algebra
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Frame length optimization for multi-antenna downlink systems based on delay-bound violation probability constraints
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作者 谭雨凤 李俊超 +1 位作者 夏玮玮 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期163-169,共7页
A flame length optimization scheme is proposed for multi-antenna downlink systems to guarantee diverse delay- bound violation probability constraints. Due to the difficulties of extracting the quality of service (QoS... A flame length optimization scheme is proposed for multi-antenna downlink systems to guarantee diverse delay- bound violation probability constraints. Due to the difficulties of extracting the quality of service (QoS) metrics from the conventional physical-layer channel models, the link-layer models named effective bandwidth and effective capacity are applied to statistically characterize the source traffic patterns and the queuing service dynamics. With these link-layer models, the source traffic process and the channel service process are mapped to certain QoS parameters. The packet delay-bound violation probability constraints are converted into minimum data rate constraints and the optimization problem is thus formulated into simultaneous inequalities. With the assumption of ergodic block-fading channels, the optimal frame lengths of single-user and multiuser systems are calculated respectively by numerical iterative methods. Theoretical analyses and simulation results show that the given delay-bound violation probability constraints are well satisfied with the optimal frame length. 展开更多
关键词 delay-bound violation probability frame lengthoptimization effective bandwidth effective capacity multi-antenna systems quality of service
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