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Multimodal Sentiment Analysis Based on a Cross-Modal Multihead Attention Mechanism
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作者 Lujuan Deng Boyi Liu Zuhe Li 《Computers, Materials & Continua》 SCIE EI 2024年第1期1157-1170,共14页
Multimodal sentiment analysis aims to understand people’s emotions and opinions from diverse data.Concate-nating or multiplying various modalities is a traditional multi-modal sentiment analysis fusion method.This fu... Multimodal sentiment analysis aims to understand people’s emotions and opinions from diverse data.Concate-nating or multiplying various modalities is a traditional multi-modal sentiment analysis fusion method.This fusion method does not utilize the correlation information between modalities.To solve this problem,this paper proposes amodel based on amulti-head attention mechanism.First,after preprocessing the original data.Then,the feature representation is converted into a sequence of word vectors and positional encoding is introduced to better understand the semantic and sequential information in the input sequence.Next,the input coding sequence is fed into the transformer model for further processing and learning.At the transformer layer,a cross-modal attention consisting of a pair of multi-head attention modules is employed to reflect the correlation between modalities.Finally,the processed results are input into the feedforward neural network to obtain the emotional output through the classification layer.Through the above processing flow,the model can capture semantic information and contextual relationships and achieve good results in various natural language processing tasks.Our model was tested on the CMU Multimodal Opinion Sentiment and Emotion Intensity(CMU-MOSEI)and Multimodal EmotionLines Dataset(MELD),achieving an accuracy of 82.04% and F1 parameters reached 80.59% on the former dataset. 展开更多
关键词 Emotion analysis deep learning cross-modal attention mechanism
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A Robust Framework for Multimodal Sentiment Analysis with Noisy Labels Generated from Distributed Data Annotation
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作者 Kai Jiang Bin Cao Jing Fan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2965-2984,共20页
Multimodal sentiment analysis utilizes multimodal data such as text,facial expressions and voice to detect people’s attitudes.With the advent of distributed data collection and annotation,we can easily obtain and sha... Multimodal sentiment analysis utilizes multimodal data such as text,facial expressions and voice to detect people’s attitudes.With the advent of distributed data collection and annotation,we can easily obtain and share such multimodal data.However,due to professional discrepancies among annotators and lax quality control,noisy labels might be introduced.Recent research suggests that deep neural networks(DNNs)will overfit noisy labels,leading to the poor performance of the DNNs.To address this challenging problem,we present a Multimodal Robust Meta Learning framework(MRML)for multimodal sentiment analysis to resist noisy labels and correlate distinct modalities simultaneously.Specifically,we propose a two-layer fusion net to deeply fuse different modalities and improve the quality of the multimodal data features for label correction and network training.Besides,a multiple meta-learner(label corrector)strategy is proposed to enhance the label correction approach and prevent models from overfitting to noisy labels.We conducted experiments on three popular multimodal datasets to verify the superiority of ourmethod by comparing it with four baselines. 展开更多
关键词 Distributed data collection multimodal sentiment analysis meta learning learn with noisy labels
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MAIPFE:An Efficient Multimodal Approach Integrating Pre-Emptive Analysis,Personalized Feature Selection,and Explainable AI
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作者 Moshe Dayan Sirapangi S.Gopikrishnan 《Computers, Materials & Continua》 SCIE EI 2024年第5期2229-2251,共23页
Medical Internet of Things(IoT)devices are becoming more and more common in healthcare.This has created a huge need for advanced predictive health modeling strategies that can make good use of the growing amount of mu... Medical Internet of Things(IoT)devices are becoming more and more common in healthcare.This has created a huge need for advanced predictive health modeling strategies that can make good use of the growing amount of multimodal data to find potential health risks early and help individuals in a personalized way.Existing methods,while useful,have limitations in predictive accuracy,delay,personalization,and user interpretability,requiring a more comprehensive and efficient approach to harness modern medical IoT devices.MAIPFE is a multimodal approach integrating pre-emptive analysis,personalized feature selection,and explainable AI for real-time health monitoring and disease detection.By using AI for early disease detection,personalized health recommendations,and transparency,healthcare will be transformed.The Multimodal Approach Integrating Pre-emptive Analysis,Personalized Feature Selection,and Explainable AI(MAIPFE)framework,which combines Firefly Optimizer,Recurrent Neural Network(RNN),Fuzzy C Means(FCM),and Explainable AI,improves disease detection precision over existing methods.Comprehensive metrics show the model’s superiority in real-time health analysis.The proposed framework outperformed existing models by 8.3%in disease detection classification precision,8.5%in accuracy,5.5%in recall,2.9%in specificity,4.5%in AUC(Area Under the Curve),and 4.9%in delay reduction.Disease prediction precision increased by 4.5%,accuracy by 3.9%,recall by 2.5%,specificity by 3.5%,AUC by 1.9%,and delay levels decreased by 9.4%.MAIPFE can revolutionize healthcare with preemptive analysis,personalized health insights,and actionable recommendations.The research shows that this innovative approach improves patient outcomes and healthcare efficiency in the real world. 展开更多
关键词 Predictive health modeling Medical Internet of Things explainable artificial intelligence personalized feature selection preemptive analysis
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 Structural health monitoring data information modal parameters damage identification AI method
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Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems
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作者 Sabrina Meddah Sid Ahmed Tadjer +3 位作者 Abdelhakim Idir Kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche 《Structural Durability & Health Monitoring》 EI 2025年第1期77-103,共27页
Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emp... Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is required.This study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling equipment.The study specifically investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency stick-slip.These events not only hinder the efficiency of drilling but also lead to exhaustion and harm to the system’s components since they are difficult to be detected and controlled in real time.The study investigates the dynamic interactions of these vibrations,specifically in their high-frequency modes,usingfield data obtained from measurement while drilling.Thefindings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem performance.The obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control systems.Therefore,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect damage.Moreover,by exploiting thesefindings,the assessment of structural resilience in rotary drilling systems can be enhanced.Furthermore,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efficiency of rotary drilling systems in the petroleum industry. 展开更多
关键词 Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis field data analysis
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Research status and prospects of the fractal analysis of metal material surfaces and interfaces
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作者 Qinjin Dai Xuefeng Liu +2 位作者 Xin Ma Shaojie Tian Qinghe Cui 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期20-38,共19页
As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal... As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal materials at various scales and dimensions.Conventional methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and interfaces.However,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal materials.From the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear surfaces.The relationship between the fractal dimensions and properties of metal material surfaces and interfaces is summarized.Starting from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be developed.It is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future. 展开更多
关键词 metal material surfaces and interfaces fractal analysis fractal dimension HOMOGENEITY
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A Multimodal Critical Discourse Analysis of Lingnan Cultural Promotional Videos on Social Media
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作者 Lu Jiang 《Journal of Contemporary Educational Research》 2024年第4期59-68,共10页
In recent years,more and more directors of culture and tourism have taken part in the promotion of local cultural tourism by cross-dressing,talent shows,and pushing their limits on self-media platforms.This study inve... In recent years,more and more directors of culture and tourism have taken part in the promotion of local cultural tourism by cross-dressing,talent shows,and pushing their limits on self-media platforms.This study investigates short videos of Lingnan culture promoted by directors general and deputy directors general of the Culture,Radio,Television,Tourism,and Sports Bureau of counties and cities in Guangdong Province on social media by the method of multimodal critical discourse analysis.The analysis of 33 videos shows that Lingnan culture is a domineering and confident culture,historical culture,graceful and elegant culture,and vibrant and active culture.Domineering and confident culture is embedded in the utterances and behaviors of the directors general or deputy directors general in the video.Historical culture is realized through the conversation with historical figures through time travel.Graceful and elegant culture is constructed in the depiction of sceneries and the depiction of characters’manners.Vibrant and active culture is represented in the depiction of the characters’actional process and analytical process. 展开更多
关键词 Lingnan culture Multimodal critical discourse analysis Promotional videos TikTok WeChat
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A Study of the English Translation of Characteristic Cuisines of the Hexi Corridor from the Perspective of Multimodal Discourse Analysis
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作者 Jing Luo 《Journal of Contemporary Educational Research》 2024年第10期170-177,共8页
Given the diversity of geographical and cultural backgrounds,it is difficult to find precise counterparts of many food-related vocabularies in the unique dietary culture of the Hexi Corridor in the target language,mak... Given the diversity of geographical and cultural backgrounds,it is difficult to find precise counterparts of many food-related vocabularies in the unique dietary culture of the Hexi Corridor in the target language,making it challenging to fully convey the essence of its local dietary culture in translation.To achieve the purpose of translation,the theory of multimodal discourse analysis provides an ideal translation approach through the language mode,image mode,sound mode,and the synergistic effect of multimodalities,which can accurately address the deficiencies in the translation of dietary culture.Through this research,it is not only possible to highlight the unique charm of the dietary culture of the Hexi Corridor but also to build a bridge for its international dissemination,promoting cross-border cultural exchanges and mutual understanding. 展开更多
关键词 Multimodal discourse analysis Hexi Corridor Characteristic cuisine English translation study
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Analysis of Commuting Modal Shift in Consideration of Social Interaction of Consciousness for Environment
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作者 Masashi Okushima 《Journal of Traffic and Transportation Engineering》 2024年第2期63-80,共18页
It is the matter for achievement of the low carbon transport system that the excessive use of private vehicles can be controlled appropriately.Not only improvement of service level of modes except private vehicle,but ... It is the matter for achievement of the low carbon transport system that the excessive use of private vehicles can be controlled appropriately.Not only improvement of service level of modes except private vehicle,but also consciousness for environmental problem of individual trip maker is important for eco-commuting promotion.On the other hand,consciousness for environment would be changed by influence of other person.Accordingly,it is aimed in the study that the structure of decision-making process for modal shift to the eco-commuting mode in the local city is described considering environmental consciousness and social interaction.For the purpose,the consciousness for the environment problem and the travel behavior of the commuter at the suburban area in the local city are investigated by the questionnaire survey.The covariance structure about the eco-consciousness is analyzed with the database of the questionnaire survey by structural equation modeling.As the result,it can be confirmed with the structural equation model that the individual environmental consciousness is strongly related with the intention of self-sacrifice and is influenced with the local interaction of the individual connections.On the other hand,the intention of modal shift for the commuting mode is analyzed with the database of the questionnaire survey.It can be found out that the environmental consciousness is not statistically significant for commuting mode choice with the present poor level of service of public transport.However,the intention of self-sacrifice for the prevention of the global warming is statistically confirmed as the factor of modal shift with the operation of eco-commuting bus service with the RP/SP integrated estimation method.As the result,the multi-agent simulation system with social interaction model for eco consciousness is developed to measure the effect of the eco-commuting promotion.For the purpose,the carbon dioxide emission is estimated based on traffic demand and road network condition in the traffic environment model.On the other hand,the relation between agents is defined based on the small world network.The proposed multi-agent simulation is applied to measure the effect of the eco-commuting promotion such as improvement of level of service on the public transport or education of eco-consciousness.The effect of the promotion plan can be observed with the proposed multi-agent system.Finally,it can be concluded that the proposed multi-agent simulation with social interaction for eco-consciousness is useful for planning of eco-commuting promotion. 展开更多
关键词 Greenhouse gas emission modal shift structural equation model RP/SP combined estimation multi-agent simulation local interaction small world network consciousness for environment commuting shuttle bus local city
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Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury
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作者 Xizi Song Ruixin Li +6 位作者 Xiaolei Chu Qi Li Ruihua Li Qingwen Li Kai-Yu Tong Xiaosong Gu Dong Ming 《Neural Regeneration Research》 SCIE CAS 2025年第10期2807-2822,共16页
Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes... Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target organs.This has led to restrictions on current therapeutic approaches.In this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target organs.After peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal cord.The nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury site.Corresponding damage to target organs can occur,including skeletal muscle atrophy and sensory receptor disruption.We then provide a brief review of the research advances in therapeutic approaches to peripheral nerve injury.The main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical exercise.However,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ pathway.Therefore,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery. 展开更多
关键词 central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach
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An Analysis of Modal Verbs in Language Teaching
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作者 邵阳 《英语广场(学术研究)》 2011年第Z5期83-,94,共2页
Through classifying modal verbs from the semantic aspect and the pragmatic aspect, this paper discusses difficulties that students may encounter in modal verb learning. It indicates that modal verbs have complicacy, a... Through classifying modal verbs from the semantic aspect and the pragmatic aspect, this paper discusses difficulties that students may encounter in modal verb learning. It indicates that modal verbs have complicacy, and a deductive approach and inductive approach should intermingle as an appropriate method to improve students' accuracy in use of modal verbs. 展开更多
关键词 modal VERBS semantic CLASSIFICATION PRAGMATIC CLASSIFICATION inductive/deductive approach
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Analysis on the Modality of English News Report
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作者 肖蓉 《科技信息》 2011年第11期I0265-I0265,I0283,共2页
Modality is used to express subjective judgment as well as the speaker’s opinions and attitudes.This paper aims to analyze the reporters’orientation reflected by linguistic modal expressions in English news reports ... Modality is used to express subjective judgment as well as the speaker’s opinions and attitudes.This paper aims to analyze the reporters’orientation reflected by linguistic modal expressions in English news reports from the perspective of Systemic-Functional Grammar,especially from the perspective of type,value,orientation and polarity. 展开更多
关键词 modalITY NEWS REPORTS SYSTEMIC FUNCTIONAL GRAMMAR
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Effects of Joint Controller on Analytical Modal Analysis of Rotational Flexible Manipulator 被引量:7
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作者 CHU Ming ZHANG Yanheng +1 位作者 CHEN Gang SUN Hanxu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期460-469,共10页
Modal analysis is a fundamental and important task for modeling and control of the flexible manipulator. However, almost all of the traditional modal analysis methods view the flexible manipulator as a pure mechanical... Modal analysis is a fundamental and important task for modeling and control of the flexible manipulator. However, almost all of the traditional modal analysis methods view the flexible manipulator as a pure mechanical structure and neglect feedback action of joint controller. In order to study the effects of joint controller on the modal analysis of rotational flexible manipulator, a closed-loop analytical modal analysis method is proposed. Firstly, two exact boundary constraints, namely servo feedback constraint and bending moment constraint, are derived to solve the vibration partial differential equation. It is found that the stiffness and damping gains of joint controller are both included in the boundary conditions, which lead to an unconventional secular term. Secondly, analytical algorithm based on Ritz approach is developed by using Laplace transform and complex modal approach to obtain the natural frequencies and mode shapes. And then, the numerical simulations are performed and the computational results show that joint controller has pronounced influence on the modal parameters: joint controller stiffness reduces the natural frequency, while joint controller damping makes the shape phase non-zero. Furthermore, the validity of the presented conclusion is confirmed through experimental studies. These findings are expected to improve the performance of dynamics simulation systems and model-based controllers. 展开更多
关键词 flexible manipulator analytical modal analysis boundary constraints joint controller
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An operational modal analysis method in frequency and spatial domain 被引量:9
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作者 王彤 张令弥 田村幸雄 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第2期295-300,共6页
A frequency and spatial domain decomposition method (FSDD) for operational modal analysis (OMA) is presented in this paper, which is an extension of the complex mode indicator function (CMIF) method for experime... A frequency and spatial domain decomposition method (FSDD) for operational modal analysis (OMA) is presented in this paper, which is an extension of the complex mode indicator function (CMIF) method for experimental modal analysis (EMA). The theoretical background of the FSDD method is clarified, Singular value decomposition is adopted to separate the signal space from the noise space. Finally, an enhanced power spectrum density (PSD) is proposed to obtain more accurate modal parameters by curve fitting in the frequency domain. Moreover, a simulation case and an application case are used to validate this method. 展开更多
关键词 operational modal analysis modal parameters identification frequency and spatial domain
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An improved modal pushover analysis procedure for estimating seismic demands of structures 被引量:5
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作者 毛建猛 翟长海 谢礼立 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第1期25-31,共7页
The pushover analysis (POA) procedure is difficult to apply to high-rise buildings, as it cannot account for the contributions of higher modes. To overcome this limitation, a modal pushover analysis (MPA) procedur... The pushover analysis (POA) procedure is difficult to apply to high-rise buildings, as it cannot account for the contributions of higher modes. To overcome this limitation, a modal pushover analysis (MPA) procedure was proposed by Chopra et al. (2001). However, invariable lateral force distributions are still adopted in the MPA. In this paper, an improved MPA procedure is presented to estimate the seismic demands of structures, considering the redistribution of inertia forces after the structure yields. This improved procedure is verified with numerical examples of 5-, 9- and 22-story buildings. It is concluded that the improved MPA procedure is more accurate than either the POA procedure or MPA procedure. In addition, the proposed procedure avoids a large computational effort by adopting a two-phase lateral force distribution.. 展开更多
关键词 seismic demand estimation pushover analysis improved modal pushover analysis two-phase lateral forcedistribution capacity curve
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Modal analysis on transverse vibration of axially moving roller chain coupled with lumped mass 被引量:4
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作者 许立新 杨玉虎 +1 位作者 常宗瑜 刘建平 《Journal of Central South University》 SCIE EI CAS 2011年第1期108-115,共8页
The modal characteristics of the transverse vibration of an axially moving roller chain coupled with lumped mass were analyzed.The chain system was modeled by using the multi-body dynamics theory and the governing equ... The modal characteristics of the transverse vibration of an axially moving roller chain coupled with lumped mass were analyzed.The chain system was modeled by using the multi-body dynamics theory and the governing equations were derived by means of Lagrange's equations.The effects of the parameters,such as the axially moving velocity of the chain,the tension force,the weight of lumped mass and its time-variable assign position in chain span,on the modal characteristics of transverse vibration for roller chain were investigated.The numerical examples were given.It is found that the natural frequencies and the corresponding mode shapes of the transverse vibration for roller chain coupled with lumped mass change significantly when the variations of above parameters are considered.With the movement of the chain strand,the natural frequencies present a fluctuating phenomenon,which is different from the uniform chain.The higher the order of mode is,the greater the fluctuating magnitude and frequency are. 展开更多
关键词 roller chain modal analysis transverse vibration lumped mass
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Finite Element Modeling and Modal Analysis of Complicated Structure with Bolted Joints 被引量:3
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作者 蒲大宇 廖日东 +1 位作者 左正兴 冯慧华 《Journal of Beijing Institute of Technology》 EI CAS 2009年第3期273-277,共5页
A contact bolt model is proposed as a new modeling technique to investigate the complex structure with bolted joints for modal analysis and compared with the coupled bolt model, and the test results are given. Among t... A contact bolt model is proposed as a new modeling technique to investigate the complex structure with bolted joints for modal analysis and compared with the coupled bolt model, and the test results are given. Among these models, the coupled bolt model provides the best accurate responses compared with the experimental results. The contact bolt model shows the best effectiveness and usefulness in view of operational time. The bolt models proposed in this study are adopted for a dynamic characteristic analysis of a large diesel engine consisting of several parts which are connected by many bolts. The dynamic behavior of the entire engine structure was investigated by experiment. The coupled bolt model and the contact bolt model were applied to model the assembly of engine with high preload. The experimental results are in good agreement with the finite element method (FEM) results. Compared with the other models, the contact bolt model presented in this paper is more effective and useful in view of operational time and experience of analysts. 展开更多
关键词 finite element method(FEM) bolted joints modal analysis internal combustion engine
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Modal analysis of coupled vibration of belt drive systems 被引量:2
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作者 李晓军 陈立群 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第1期9-13,共5页
The modal method is applied to analyze coupled vibration of belt drive systems. A belt drive system is a hybrid system consisting of continuous belts modeled as strings as well as discrete pulleys and a tensioner arm.... The modal method is applied to analyze coupled vibration of belt drive systems. A belt drive system is a hybrid system consisting of continuous belts modeled as strings as well as discrete pulleys and a tensioner arm. The characteristic equation of the system is derived from the governing equation. Numerical results demenstrate the effects of the transport speed and the initial tension on natural frequencies. 展开更多
关键词 belt drive system modal analysis axially moving string coupled vibration FREQUENCY
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CALCULATING RESPONSE SPECTRAL MOMENTS BY COMPLEX MODAL ANALYSIS 被引量:2
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作者 Fang Tong Zhang Tianshu (Northwestern Polytechnical University) 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1989年第2期159-166,共8页
Response spectral moments are useful for system reliability analysis.Usually,spectral mo- ments are calculated by the frequency domain method.Based on the time domain modal analysis of random vibrations,the authors pr... Response spectral moments are useful for system reliability analysis.Usually,spectral mo- ments are calculated by the frequency domain method.Based on the time domain modal analysis of random vibrations,the authors present a new method for calculating response spectral moments through response correlation functions.The method can be applied to both classical and non-classical damping cases and to three kinds of random excitations,i.e.,white noise,band-limited white noise, and filtered white noise. 展开更多
关键词 spectral moment random response reliability analysis modal analysis
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Modal analysis of 4-cylinder engine crankshaft based on ANSYS Workbench 被引量:3
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作者 李学民 崔志琴 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第3期282-285,共4页
CATIA V5R20 software was utilized to build up a three-dimensional solid model of inline four-cylinder gasoline engine crankshaft.The free modal analysis of the first six orders from the whole crankshaft model was carr... CATIA V5R20 software was utilized to build up a three-dimensional solid model of inline four-cylinder gasoline engine crankshaft.The free modal analysis of the first six orders from the whole crankshaft model was carried out based on TGrid algorithm by using ANSYS Workbench14.0software and the natural frequency and vibration modes were obtained.The reliability of the finite element model was verified by comparing with modal test result.This provides a reference for further design and optimization of the crankshaft. 展开更多
关键词 ANSYS workbench model analysis natural frequency vibration mode
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