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An Analysis on the BRICS TALK from the Perspective of Modality System
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作者 MI Cheng-fei 《Journal of Literature and Art Studies》 2020年第5期414-424,共11页
The tenth BRICS Summit was held in Johannesburg,South Africa in 2018,which attracted attention from the whole world.Especially,it is of great importance to the BRICS nations,for it is the first ten years of BRICS,whic... The tenth BRICS Summit was held in Johannesburg,South Africa in 2018,which attracted attention from the whole world.Especially,it is of great importance to the BRICS nations,for it is the first ten years of BRICS,which marks its growth.Meanwhile,this year the Trump administration imposed more strict policies on protectionism.Particularly,the trade war between China and the United States is so intensive.China,as the core member of BRICS has great clout on BRICS,so the trade war between China and US also arouse a heat discussion among the BRICS nations.During the Summit,CGTN invited experts from the five BRICS nations to discuss related topics.Systemic Functional Linguistics,as one of the most influential branches of Linguistics,was firstly established by M.A.K.Halliday,and it has been greatly developed over the past decades.Interpersonal meaning is one of the three meta-functions,which focuses on how addressers use language to communicate,establish and maintain relationships with addressees,and express their opinions.Mood and modality are two basic resources to the realization of interpersonal meaning.Mood is used to represent the interaction of the language users,while modality reflects the utterers’attitudes and judgments.The paper discusses the three aspects of modality:modal operators,modal adjuncts and metaphors of modality.The paper applies the modality system to the analysis of the transcript of BRICS TALK.The author selects the experts’speeches on the trade war between China and US as the data.The research questions are as followed:(1)the characteristics of the modality resources appeared in their talks;(2)the BRICS nations attitudes and stance on trade war and America’s protectionism. 展开更多
关键词 BICKS TALK modal operators modal adjuncts metaphors of modality
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Exploration and Practice of Database System Course Based on KAPI Teaching Modality Under the Emerging Engineering Education
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作者 Hongqi Li Kexin Sun +3 位作者 Wei Lu Yong Li Chunyan Ma Hongping Gan 《计算机教育》 2023年第12期246-256,共11页
Nowadays,it is extremely urgent for the software engineering education to cultivate the knowledge and ability of database talents in the era of big data.To this end,this paper proposes a talent training teaching modal... Nowadays,it is extremely urgent for the software engineering education to cultivate the knowledge and ability of database talents in the era of big data.To this end,this paper proposes a talent training teaching modality that integrates knowledge,ability,practice,and innovation(KAPI)for Database System Course.The teaching modality contains three parts:top-level design,course learning process,and course assurance and evaluation.The top-level design sorts out the core knowledge of the course and determines a mixed online and offline teaching platform.The course learning process emphasizes the correspondence transformation relationship between core knowledge points and ability enhancement,and the course is practiced in the form of experimental projects to finally enhance students’innovation consciousness and ability.The assurance and evaluation of the course are based on the outcome-based education(OBE)orientation,which realizes the objective evaluation of students’learning process and final performance.The teaching results of the course in the past 2 years show that the KAPI-based teaching modality has achieved better results.Meanwhile,students are satisfied with the evaluation of the modality.The teaching modality in this paper helps to stimulate students’initiatives,and improve their knowledge vision and practical ability,and thus helps to cultivate innovative and high-quality engineering talents required by the emerging engineering education. 展开更多
关键词 Database system teaching KAPI modality Hybrid teaching mode OBE concept Teaching reform
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Low-frequency oscillation of train-network system considering traction power supply mode
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作者 Yuchen Liu Xiaoqin Lyu +1 位作者 Mingyuan Chang Qiqi Yang 《Railway Engineering Science》 EI 2024年第2期244-256,共13页
The low-frequency oscillation(LFO)has occurred in the train-network system due to the introduction of the power electronics of the trains.The modeling and analyzing method in current researches based on electrified ra... The low-frequency oscillation(LFO)has occurred in the train-network system due to the introduction of the power electronics of the trains.The modeling and analyzing method in current researches based on electrified railway unilateral power supply system are not suitable for the LFO analysis in a bilateral power supply system,where the trains are supplied by two traction substations.In this work,based on the single-input and single-output impedance model of China CRH5 trains,the node admittance matrices of the train-network system both in unilateral and bilateral power supply modes are established,including three-phase power grid,traction transformers and traction network.Then the modal analysis is used to study the oscillation modes and propagation characteristics of the unilateral and bilateral power supply systems.Moreover,the influence of the equivalent inductance of the power grid,the length of the transmission line,and the length of the traction network are analyzed on the critical oscillation mode of the bilateral power supply system.Finally,the theoretical analysis results are verified by the time-domain simulation model in MATLAB/Simulink. 展开更多
关键词 Low-frequency oscillation Train-network system Modal analysis Bilateral power supply Participation factor
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Technical problems and non destructive testing of rock bolt support systems in mines
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作者 Andrzej Staniek 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第1期124-135,共12页
The problem of proper assessment of the technical functionality of rock bolt support systems is still valid.Many research centers have undertaken eforts to diagnose and monitor the technical state of such a support sy... The problem of proper assessment of the technical functionality of rock bolt support systems is still valid.Many research centers have undertaken eforts to diagnose and monitor the technical state of such a support system used in mines and tunneling.With that aim the method of quality assessment of grouted rock bolts was invented and a relevant apparatus was constructed.The method concerns non-destructive identifcation of discontinuity of a resin layer(grout)surrounding rock bolts.The method is based on an impact excitation of a rock bolt and uses modal analysis procedures.Assuming that the installed rock bolt acts as an oscillator,diferent lengths and positions of grouting discontinuity alter its modal parameters.The extraction of these modal parameters,of which a resonant frequency is seen as the most valued,enable the relevant identifcation of grout discontinuity.After constructing a prototype version and validating the results for known cases of resin discontinuity in an experimental coal mine,the apparatus fulflling ATEX requirements was developed.Subsequently that version was also verifed both in laboratory conditions and in an experimental coal mine.As necessary for proper identifcation of discontinuity length,the reference data base was developed and elaborated consisting of a very large number of fnite element models(FE models),namely discontinuity cases.The models encountered diferent rock bolt lengths and diameters,diferent rock strata parameters and diferent positions and lengths of resin layers.Then the method was used in a working coal mine to monitor a technical state of rock bolt support system mounted to reinforce long underground openings.The data base was utilized as reference for investigated rock bolts. 展开更多
关键词 ROCK Rock bolt SAFETY Modal analysis MINING
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Mining Fine-Grain Face Forgery Cues with Fusion Modality
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作者 Shufan Peng Manchun Cai +1 位作者 Tianliang Lu Xiaowen Liu 《Computers, Materials & Continua》 SCIE EI 2023年第5期4025-4045,共21页
Face forgery detection is drawing ever-increasing attention in the academic community owing to security concerns.Despite the considerable progress in existing methods,we note that:Previous works overlooked finegrain f... Face forgery detection is drawing ever-increasing attention in the academic community owing to security concerns.Despite the considerable progress in existing methods,we note that:Previous works overlooked finegrain forgery cues with high transferability.Such cues positively impact the model’s accuracy and generalizability.Moreover,single-modality often causes overfitting of the model,and Red-Green-Blue(RGB)modal-only is not conducive to extracting the more detailed forgery traces.We propose a novel framework for fine-grain forgery cues mining with fusion modality to cope with these issues.First,we propose two functional modules to reveal and locate the deeper forged features.Our method locates deeper forgery cues through a dual-modality progressive fusion module and a noise adaptive enhancement module,which can excavate the association between dualmodal space and channels and enhance the learning of subtle noise features.A sensitive patch branch is introduced on this foundation to enhance the mining of subtle forgery traces under fusion modality.The experimental results demonstrate that our proposed framework can desirably explore the differences between authentic and forged images with supervised learning.Comprehensive evaluations of several mainstream datasets show that our method outperforms the state-of-the-art detection methods with remarkable detection ability and generalizability. 展开更多
关键词 Face forgery detection fine-grain forgery cues fusion modality adaptive enhancement
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Study of Axial Vibration of a Motor-Compressor System Using Operational Modal Analysis
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作者 M.Farid Yahya Reduan Mat Dan +2 位作者 M.Fadzlee Samsubaha Zaini Rashid Azma Putra 《Sound & Vibration》 EI 2023年第1期119-131,共13页
A case study of excessive vibration on a motor-compressor system is presented in this paper.After barely two months of operation,the reciprocating compressor motor’s routine monitoring revealed excessive axial vibrat... A case study of excessive vibration on a motor-compressor system is presented in this paper.After barely two months of operation,the reciprocating compressor motor’s routine monitoring revealed excessive axial vibration amplitude.For this reason,the Operational Modal Analysis(OMA)was carried out in order to identify the pri-mary cause.According to the investigation,one of the harmonic components which was 18 times the motor’s running speed matched with a resonance frequency of 112 Hz.According to OMA study,the motor was vibrating in torsional motion because the compressor’s load had stimulated the entire motor-compressor unit at this reso-nance frequency.The analysis also demonstrates the bulging effect of the motor shaft’s axial vibration on the motor’s endplate. 展开更多
关键词 Axial vibration operational modal analysis rotating machinery
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A Systemic Functional Study of the English Police Caution——An Analysis of the “Miranda Warnings”
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作者 郑洁 《英语广场(学术研究)》 2014年第4期44-46,共3页
Based on the interpersonal function in Halliday’s systemic functional grammar,"Miranda Warnings",the typical English Police Caution,is analyzed from the aspects of Mood system,Modality system and Appraisal ... Based on the interpersonal function in Halliday’s systemic functional grammar,"Miranda Warnings",the typical English Police Caution,is analyzed from the aspects of Mood system,Modality system and Appraisal system,with the aim of exploring its interpersonal meanings.Results show that:first,the declarative mood and interrogative mood used in the police caution protect the legitimate rights of the interrogated;second,the widely use of Low value modal verbs demonstrates a more humane and democratic legislation principle;and third,the absence of Affect resources and the frequent application of Capacity resources narrow the interpersonal distance between policeman and the interrogated,reflecting the transformation in policeman’s interrogation practices. 展开更多
关键词 Police Caution Miranda Warnings Mood system modality system Appraisal system
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Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers 被引量:1
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作者 DU Zun-feng ZHU Hai-ming YU Jian-xing 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期285-296,共12页
When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fa... When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real risers.The problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration modes.However,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known measurements.This study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal space.In the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring. 展开更多
关键词 motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing
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Three-Dimensional Sound Source Location Algorithm for Subsea Leakage Using Hydrophone 被引量:1
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作者 LI Hao-jie CAI Bao-ping +6 位作者 YUAN Xiao-bing KONG Xiang-di LIU Yong-hong Javed Akbar KHAN CHU Zheng-de YANG Chao TANG An-bang 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期326-337,共12页
Leakages from subsea oil and gas equipment cause substantial economic losses and damage to marine ecosystem,so it is essential to locate the source of the leak.However,due to the complexity and variability of the mari... Leakages from subsea oil and gas equipment cause substantial economic losses and damage to marine ecosystem,so it is essential to locate the source of the leak.However,due to the complexity and variability of the marine environment,the signals collected by hydrophone contain a variety of noises,which makes it challenging to extract useful signals for localization.To solve this problem,a hydrophone denoising algorithm is proposed based on variational modal decomposition(VMD)with grey wolf optimization.First,the average envelope entropy is used as the fitness function of the grey wolf optimizer to find the optimal solution for the parameters K andα.Afterward,the VMD algorithm decomposes the original signal parameters to obtain the intrinsic mode functions(IMFs).Subsequently,the number of interrelationships between each IMF and the original signal was calculated,the threshold value was set,and the noise signal was removed to calculate the time difference using the valid signal obtained by reconstruction.Finally,the arrival time difference is used to locate the origin of the leak.The localization accuracy of the method in finding leaks is investigated experimentally by constructing a simulated leak test rig,and the effectiveness and feasibility of the method are verified. 展开更多
关键词 grey wolf optimizer variational modal decomposition mean envelope entropy correlation coefficient time difference of arrival
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A Dual Discriminator Method for Generalized Zero-Shot Learning
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作者 Tianshu Wei Jinjie Huang 《Computers, Materials & Continua》 SCIE EI 2024年第4期1599-1612,共14页
Zero-shot learning enables the recognition of new class samples by migrating models learned from semanticfeatures and existing sample features to things that have never been seen before. The problems of consistencyof ... Zero-shot learning enables the recognition of new class samples by migrating models learned from semanticfeatures and existing sample features to things that have never been seen before. The problems of consistencyof different types of features and domain shift problems are two of the critical issues in zero-shot learning. Toaddress both of these issues, this paper proposes a new modeling structure. The traditional approach mappedsemantic features and visual features into the same feature space;based on this, a dual discriminator approachis used in the proposed model. This dual discriminator approach can further enhance the consistency betweensemantic and visual features. At the same time, this approach can also align unseen class semantic features andtraining set samples, providing a portion of information about the unseen classes. In addition, a new feature fusionmethod is proposed in the model. This method is equivalent to adding perturbation to the seen class features,which can reduce the degree to which the classification results in the model are biased towards the seen classes.At the same time, this feature fusion method can provide part of the information of the unseen classes, improvingits classification accuracy in generalized zero-shot learning and reducing domain bias. The proposed method isvalidated and compared with othermethods on four datasets, and fromthe experimental results, it can be seen thatthe method proposed in this paper achieves promising results. 展开更多
关键词 Generalized zero-shot learning modality consistent DISCRIMINATOR domain shift problem feature fusion
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Vibration Control of the Rail Grinding Vehicle with Abrasive Belt Based on Structural Optimization and Lightweight Design
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作者 Wengang Fan Shuai Zhang +2 位作者 Zhiwei Wu Yi Liu Jiangnan Yu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期311-337,共27页
As a new grinding and maintenance technology,rail belt grinding shows significant advantages in many applications The dynamic characteristics of the rail belt grinding vehicle largely determines its grinding performan... As a new grinding and maintenance technology,rail belt grinding shows significant advantages in many applications The dynamic characteristics of the rail belt grinding vehicle largely determines its grinding performance and service life.In order to explore the vibration control method of the rail grinding vehicle with abrasive belt,the vibration response changes in structural optimization and lightweight design are respectively analyzed through transient response and random vibration simulations in this paper.Firstly,the transient response simulation analysis of the rail grinding vehicle with abrasive belt is carried out under operating conditions and non-operating conditions.Secondly,the vibration control of the grinding vehicle is implemented by setting vibration isolation elements,optimizing the structure,and increasing damping.Thirdly,in order to further explore the dynamic characteristics of the rail grinding vehicle,the random vibration simulation analysis of the grinding vehicle is carried out under the condition of the horizontal irregularity of the American AAR6 track.Finally,by replacing the Q235 steel frame material with 7075 aluminum alloy and LA43M magnesium alloy,both vibration control and lightweight design can be achieved simultaneously.The results of transient dynamic response analysis show that the acceleration of most positions in the two working conditions exceeds the standard value in GB/T 17426-1998 standard.By optimizing the structure of the grinding vehicle in three ways,the average vibration acceleration of the whole car is reduced by about 55.1%from 15.6 m/s^(2) to 7.0 m/s^(2).The results of random vibration analysis show that the grinding vehicle with Q235 steel frame does not meet the safety conditions of 3σ.By changing frame material,the maximum vibration stress of the vehicle can be reduced from 240.7 MPa to 160.0 MPa and the weight of the grinding vehicle is reduced by about 21.7%from 1500 kg to 1175 kg.The modal analysis results indicate that the vibration control of the grinding vehicle can be realized by optimizing the structure and replacing the materials with lower stiffness under the premise of ensuring the overall strength.The study provides the basis for the development of lightweight,diversified and efficient rail grinding equipment. 展开更多
关键词 Vibration control Dynamic characteristics Structural optimization Lightweight design Modal analysis
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Anticancer effects of exercise:Insights from single-cell analysis
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作者 Abel Plaza-Florido Alejandro Lucia +1 位作者 Shlomit Radom-Aizik Carmen Fiuza-Luces 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期676-678,共3页
A recent special topic in the Journal of Sport and Health Science reported the health benefits conferred by traditional and innovative m-health exercise and multimodal programs with respect to several types of cancer.... A recent special topic in the Journal of Sport and Health Science reported the health benefits conferred by traditional and innovative m-health exercise and multimodal programs with respect to several types of cancer.1 A possible mechanism behind this protective effect could be enhanced cancer immunosurveillance. 展开更多
关键词 protective EXERCISE MODAL
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Generalized load graphical forecasting method based on modal decomposition
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作者 Lizhen Wu Peixin Chang +1 位作者 Wei Chen Tingting Pei 《Global Energy Interconnection》 EI CSCD 2024年第2期166-178,共13页
In a“low-carbon”context,the power load is affected by the coupling of multiple factors,which gradually evolves from the traditional“pure load”to the generalized load with the dual characteristics of“load+power su... In a“low-carbon”context,the power load is affected by the coupling of multiple factors,which gradually evolves from the traditional“pure load”to the generalized load with the dual characteristics of“load+power supply.”Traditional time-series forecasting methods are no longer suitable owing to the complexity and uncertainty associated with generalized loads.From the perspective of image processing,this study proposes a graphical short-term prediction method for generalized loads based on modal decomposition.First,the datasets are normalized and feature-filtered by comparing the results of Xtreme gradient boosting,gradient boosted decision tree,and random forest algorithms.Subsequently,the generalized load data are decomposed into three sets of modalities by modal decomposition,and red,green,and blue(RGB)images are generated using them as the pixel values of the R,G,and B channels.The generated images are diversified,and an optimized DenseNet neural network was used for training and prediction.Finally,the base load,wind power,and photovoltaic power generation data are selected,and the characteristic curves of the generalized load scenarios under different permeabilities of wind power and photovoltaic power generation are obtained using the density-based spatial clustering of applications with noise algorithm.Based on the proposed graphical forecasting method,the feasibility of the generalized load graphical forecasting method is verified by comparing it with the traditional time-series forecasting method. 展开更多
关键词 Load forecasting Generalized load Image processing DenseNet Modal decomposition
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Multimodal Data-Driven Reinforcement Learning for Operational Decision-Making in Industrial Processes
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作者 Chenliang Liu Yalin Wang +1 位作者 Chunhua Yang Weihua Gui 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期252-254,共3页
Dear Editor, This letter proposes a multimodal data-driven reinforcement learning-based method for operational decision-making in industrial processes. Due to the frequent fluctuations of feedstock properties and oper... Dear Editor, This letter proposes a multimodal data-driven reinforcement learning-based method for operational decision-making in industrial processes. Due to the frequent fluctuations of feedstock properties and operating conditions in the industrial processes, existing data-driven methods cannot effectively adjust the operational variables. In addition, multimodal data such as images, audio. 展开更多
关键词 processes MODAL ADJUST
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Utilization of biomarkers for the prognostic prediction of cardiac arrest survivors using a multi-modal approach
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作者 Changshin Kang Yeonho You +3 位作者 Jung Soo Park Byeong Kwon Park Jae Kwang Lee Byung Kook Lee 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第2期131-134,共4页
International guidelines for post-cardiac arrest care recommend using multi-modal strategies to avoid the withdrawal of life-sustaining therapy(WLST)in patients with the potential for neurological recovery.[1]However,... International guidelines for post-cardiac arrest care recommend using multi-modal strategies to avoid the withdrawal of life-sustaining therapy(WLST)in patients with the potential for neurological recovery.[1]However,a clear methodology for multi-modal approaches has yet to be developed.Neuron-specific enolase(NSE)is currently the only recommended biomarker,and the European Resuscitation Council(ERC)and the European SocietyofIntensiveCareMedicine(ESICM)have proposed a cutoff value of 60μg/L at 48 and/or 72 h after the return of spontaneous circulation(ROSC)as a multimodal prognostic tool for predicting poor neurological outcomes. 展开更多
关键词 CARDIAC MODAL RETURN
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Dynamic Modeling and Experimental Verification of an RPR Type Compliant Paralle Mechanism with Low Orders
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作者 Shuang Zhang Jingfang Liu +1 位作者 Huafeng Ding Yanbin Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期83-94,共12页
Efficiency of calculating a dynamic response is an important point of the compliant mechanism for posture adjustment.Dynamic modeling with low orders of a 2R1T compliant parallel mechanism is studied in the paper.The ... Efficiency of calculating a dynamic response is an important point of the compliant mechanism for posture adjustment.Dynamic modeling with low orders of a 2R1T compliant parallel mechanism is studied in the paper.The mechanism with two out-of-plane rotational and one lifting degrees of freedom(DoFs)plays an important role in posture adjustment.Based on elastic beam theory,the stiffness matrix and mass matrix of the beam element are established where the moment of inertia is considered.To improve solving efficiency,a dynamic model with low orders of the mechanism is established based on a modified modal synthesis method.Firstly,each branch of the RPR type mechanism is divided into a substructure.Subsequently,a set of hypothetical modes of each substructure is obtained based on the C-B method.Finally,dynamic equation of the whole mechanism is established by the substructure assembly.A dynamic experiment is conducted to verify the dynamic characteristics of the compliant mechanism. 展开更多
关键词 Compliant parallel mechanism Dynamic model Modal synthesis method Dynamic experiment
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Torque effect on vibration behavior of high-speed train gearbox under internal and external excitations
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作者 Yue Zhou Xi Wang +5 位作者 Hongbo Que Rubing Guo Xinhai Lin Siqin Jin Chengpan Wu Yu Hou 《Railway Engineering Science》 EI 2024年第2期229-243,共15页
The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavio... The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavior in the actual service environment.This paper focuses on the gearbox in the high-speed train to carry out the bench test,in which various operat-ing conditions(torques and rotation speeds)were set up and the excitation condition covering both internal and external was created.Acceleration responses on multiple positions of the gearbox were acquired in the test and the vibration behavior of the gearbox was studied.Meanwhile,a stochastic excitation modal test was also carried out on the test bench under different torques,and the modal parameter of the gearbox was identified.Finally,the sweep frequency response of the gearbox under gear meshing excitation was analyzed through dynamic modeling.The results showed that the torque has an attenuating effect on the amplitude of gear meshing frequency on the gearbox,and the effect of external excitation on the gearbox vibration cannot be ignored,especially under the rated operating condition.It was also found that the torque affects the modal param-eter of the gearbox significantly.The torque has a great effect on both the gear meshing stiffness and the bearing stiffness in the transmission system,which is the inherent reason for the changed modal characteristics observed in the modal test and affects the vibration behavior of the gearbox consequently. 展开更多
关键词 High-speed train GEARBOX Bench test Vibration behavior Modal identification
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A Comprehensive Survey for Privacy-Preserving Biometrics: Recent Approaches, Challenges, and Future Directions
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作者 Shahriar Md Arman Tao Yang +3 位作者 Shahadat Shahed Alanoud AlMazroa Afraa Attiah Linda Mohaisen 《Computers, Materials & Continua》 SCIE EI 2024年第2期2087-2110,共24页
The rapid growth of smart technologies and services has intensified the challenges surrounding identity authenti-cation techniques.Biometric credentials are increasingly being used for verification due to their advant... The rapid growth of smart technologies and services has intensified the challenges surrounding identity authenti-cation techniques.Biometric credentials are increasingly being used for verification due to their advantages over traditional methods,making it crucial to safeguard the privacy of people’s biometric data in various scenarios.This paper offers an in-depth exploration for privacy-preserving techniques and potential threats to biometric systems.It proposes a noble and thorough taxonomy survey for privacy-preserving techniques,as well as a systematic framework for categorizing the field’s existing literature.We review the state-of-the-art methods and address their advantages and limitations in the context of various biometric modalities,such as face,fingerprint,and eye detection.The survey encompasses various categories of privacy-preserving mechanisms and examines the trade-offs between security,privacy,and recognition performance,as well as the issues and future research directions.It aims to provide researchers,professionals,and decision-makers with a thorough understanding of the existing privacy-preserving solutions in biometric recognition systems and serves as the foundation of the development of more secure and privacy-preserving biometric technologies. 展开更多
关键词 Biometric modalities biometric recognition biometric security PRIVACY-PRESERVING security threats
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A Combination Prediction Model for Short Term Travel Demand of Urban Taxi
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作者 Mingyuan Li Yuanli Gu +1 位作者 Qingqiao Geng Hongru Yu 《Computers, Materials & Continua》 SCIE EI 2024年第6期3877-3896,共20页
This study proposes a prediction model considering external weather and holiday factors to address the issue of accurately predicting urban taxi travel demand caused by complex data and numerous influencing factors.Th... This study proposes a prediction model considering external weather and holiday factors to address the issue of accurately predicting urban taxi travel demand caused by complex data and numerous influencing factors.The model integrates the Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)and Convolutional Long Short Term Memory Neural Network(ConvLSTM)to predict short-term taxi travel demand.The CEEMDAN decomposition method effectively decomposes time series data into a set of modal components,capturing sequence characteristics at different time scales and frequencies.Based on the sample entropy value of components,secondary processing of more complex sequence components after decomposition is employed to reduce the cumulative prediction error of component sequences and improve prediction efficiency.On this basis,considering the correlation between the spatiotemporal trends of short-term taxi traffic,a ConvLSTM neural network model with Long Short Term Memory(LSTM)time series processing ability and Convolutional Neural Networks(CNN)spatial feature processing ability is constructed to predict the travel demand for urban taxis.The combined prediction model is tested on a taxi travel demand dataset in a certain area of Beijing.The results show that the CEEMDAN-ConvLSTM prediction model outperforms the LSTM,Autoregressive Integrated Moving Average model(ARIMA),CNN,and ConvLSTM benchmark models in terms of Symmetric Mean Absolute Percentage Error(SMAPE),Root Mean Square Error(RMSE),Mean Absolute Error(MAE),and R2 metrics.Notably,the SMAPE metric exhibits a remarkable decline of 21.03%with the utilization of our proposed model.These results confirm that our study provides a highly accurate and valid model for taxi travel demand forecasting. 展开更多
关键词 Urban transport taxi travel demand prediction CEEMDAN-ConvLSTM modal components
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Influence of Trailing-Edge Wear on the Vibrational Behavior of Wind Turbine Blades
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作者 Yuanjun Dai Xin Wei +2 位作者 Baohua Li Cong Wang Kunju Shi 《Fluid Dynamics & Materials Processing》 EI 2024年第2期337-348,共12页
To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades,unworn blades and trailing-edge worn blades have been assessed through relevant modal tests.According to these experimen... To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades,unworn blades and trailing-edge worn blades have been assessed through relevant modal tests.According to these experiments,the natural frequencies of trailing-edge worn blades-1,-2,and-3 increase the most in the second to fourth order,thefifth order increases in the middle,and thefirst order increases the least.The damping ratio data indi-cate that,in general,thefirstfive-order damping ratios of trailing-edge worn blades-1 and trailing-edge worn blades-2 are reduced,and thefirstfive-order damping ratios of trailing-edge worn blades-3 are slightly improved.The mode shape diagram shows that the trailing-edge worn blades-1 and-2 have a large swing in the tip and the blade,whereas the second-and third-order vibration shapes of the trailing edge-worn blade-3 tend to be improved.Overall,all these results reveal that the blade’s mass and the wear area are the main fac-tors affecting the vibration characteristics of wind turbine blades. 展开更多
关键词 Wind turbine modal test natural frequency damping ratio mode shape
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