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Prediction of lime utilization ratio of dephosphorization in BOF steelmaking based on online sequential extreme learning machine with forgetting mechanism
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作者 Runhao Zhang Jian Yang +1 位作者 Han Sun Wenkui Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期508-517,共10页
The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting me... The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting mechanism(FOS-ELM)are applied in the prediction of the lime utilization ratio of dephosphorization in the basic oxygen furnace steelmaking process.The ELM model exhibites the best performance compared with the models of MLR and SVR.OS-ELM and FOS-ELM are applied for sequential learning and model updating.The optimal number of samples in validity term of the FOS-ELM model is determined to be 1500,with the smallest population mean absolute relative error(MARE)value of 0.058226 for the population.The variable importance analysis reveals lime weight,initial P content,and hot metal weight as the most important variables for the lime utilization ratio.The lime utilization ratio increases with the decrease in lime weight and the increases in the initial P content and hot metal weight.A prediction system based on FOS-ELM is applied in actual industrial production for one month.The hit ratios of the predicted lime utilization ratio in the error ranges of±1%,±3%,and±5%are 61.16%,90.63%,and 94.11%,respectively.The coefficient of determination,MARE,and root mean square error are 0.8670,0.06823,and 1.4265,respectively.The system exhibits desirable performance for applications in actual industrial pro-duction. 展开更多
关键词 basic oxygen furnace steelmaking machine learning lime utilization ratio DEPHOSPHORIZATION online sequential extreme learning machine forgetting mechanism
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Gas liquid cylindrical cyclone flow regime identification using machine learning combined with experimental mechanism explanation
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作者 Zhao-Ming Yang Yu-Xuan He +6 位作者 Qi Xiang Enrico Zio Li-Min He Xiao-Ming Luo Huai Su Ji Wang Jin-Jun Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期540-558,共19页
The flow regimes of GLCC with horizon inlet and a vertical pipe are investigated in experiments,and the velocities and pressure drops data labeled by the corresponding flow regimes are collected.Combined with the flow... The flow regimes of GLCC with horizon inlet and a vertical pipe are investigated in experiments,and the velocities and pressure drops data labeled by the corresponding flow regimes are collected.Combined with the flow regimes data of other GLCC positions from other literatures in existence,the gas and liquid superficial velocities and pressure drops are used as the input of the machine learning algorithms respectively which are applied to identify the flow regimes.The choosing of input data types takes the availability of data for practical industry fields into consideration,and the twelve machine learning algorithms are chosen from the classical and popular algorithms in the area of classification,including the typical ensemble models,SVM,KNN,Bayesian Model and MLP.The results of flow regimes identification show that gas and liquid superficial velocities are the ideal type of input data for the flow regimes identification by machine learning.Most of the ensemble models can identify the flow regimes of GLCC by gas and liquid velocities with the accuracy of 0.99 and more.For the pressure drops as the input of each algorithm,it is not the suitable as gas and liquid velocities,and only XGBoost and Bagging Tree can identify the GLCC flow regimes accurately.The success and confusion of each algorithm are analyzed and explained based on the experimental phenomena of flow regimes evolution processes,the flow regimes map,and the principles of algorithms.The applicability and feasibility of each algorithm according to different types of data for GLCC flow regimes identification are proposed. 展开更多
关键词 Gas liquid cylindrical cyclone machine learning Flow regimes identification mechanism explanation ALGORITHMS
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Exploration on the mechanism of therapeutic and toxic bidirectional effects of Haizao Yuhu decoction based on machine learning and data mining
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作者 Yu-Han Chen Ping-Ping Yang +3 位作者 Chun-Lan Feng Xiang-He Kong Hao-Jing Jiang Lin-Lin Xiu 《Medical Data Mining》 2023年第4期8-20,共13页
Objective:To explore the bidirectional mechanism of Haizao Yuhu decoction(HYD)on goiter and drug-induced liver injury(DILI)based on machine learning and data mining.Methods:Firstly,compounds of HYD were selected from ... Objective:To explore the bidirectional mechanism of Haizao Yuhu decoction(HYD)on goiter and drug-induced liver injury(DILI)based on machine learning and data mining.Methods:Firstly,compounds of HYD were selected from the TCMSP,TCMIP,and BATMAN databases,then the TCMSP was used to acquire the targets of compounds.Targets of goiter and DILI were obtained from the GeneCards database.Secondly,common targets of“HYD-goiter”and“HYD-DILI”as well as related compounds were used to construct the networks and perform Random Walk with Restart(RWR)algorithm and network stability test.Finally,core targets in the“HYD-goiter”and“HYD-DILI”networks were used for molecular docking with core compounds and searched for validation on PubChem,and the relevant experimental data of our group were quoted to verify the analysis results.Results:There were 22 intersection targets of HYD and DILI,326 of HYD and goiter.RWR analysis showed that MAPK1,MAPK3,AKT1,etc.may be the core targets of HYD treating goiter,RELA,TNF,IL4,etc.may be the core targets of the bidirectional effect,and eckol may be the core compound in bidirectional effect.Network stability test indicated that the HYD had a high stability on treating goiter and playing a bidirectional effect.The core targets and core compounds docked well,and 37.3%of targets had been confirmed by experiments and 29.8%core targets had been confirmed.Our previous experimental result confirmed that the HYD could treat goiter usefully by reducing the expression levels of PI3K and AKT mRNA,and down-regulating the expression of Cyclin D1 and Bcl-2 mRNA.Conclusion:HYD containing“sargassum-liquorice”combination may have a bidirectional effect on treating goiter and causing DILI.We offered a new way for more explorations on the therapeutic and toxic bidirectional mechanisms based on machine learning and data mining. 展开更多
关键词 machine learning bidirectional mechanism GOITER drug-induced liver injury
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Nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in aerospace community:a comparative analysis 被引量:2
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作者 Guolong Zhao Biao Zhao +5 位作者 Wenfeng Ding Lianjia Xin Zhiwen Nian Jianhao Peng Ning He Jiuhua Xu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期190-271,共82页
The aerospace community widely uses difficult-to-cut materials,such as titanium alloys,high-temperature alloys,metal/ceramic/polymer matrix composites,hard and brittle materials,and geometrically complex components,su... The aerospace community widely uses difficult-to-cut materials,such as titanium alloys,high-temperature alloys,metal/ceramic/polymer matrix composites,hard and brittle materials,and geometrically complex components,such as thin-walled structures,microchannels,and complex surfaces.Mechanical machining is the main material removal process for the vast majority of aerospace components.However,many problems exist,including severe and rapid tool wear,low machining efficiency,and poor surface integrity.Nontraditional energy-assisted mechanical machining is a hybrid process that uses nontraditional energies(vibration,laser,electricity,etc)to improve the machinability of local materials and decrease the burden of mechanical machining.This provides a feasible and promising method to improve the material removal rate and surface quality,reduce process forces,and prolong tool life.However,systematic reviews of this technology are lacking with respect to the current research status and development direction.This paper reviews the recent progress in the nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in the aerospace community.In addition,this paper focuses on the processing principles,material responses under nontraditional energy,resultant forces and temperatures,material removal mechanisms,and applications of these processes,including vibration-,laser-,electric-,magnetic-,chemical-,advanced coolant-,and hybrid nontraditional energy-assisted mechanical machining.Finally,a comprehensive summary of the principles,advantages,and limitations of each hybrid process is provided,and future perspectives on forward design,device development,and sustainability of nontraditional energy-assisted mechanical machining processes are discussed. 展开更多
关键词 difficult-to-cut materials geometrically complex components nontraditional energy mechanical machining aerospace community
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Machine Learning‑Enhanced Flexible Mechanical Sensing 被引量:7
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作者 Yuejiao Wang Mukhtar Lawan Adam +4 位作者 Yunlong Zhao Weihao Zheng Libo Gao Zongyou Yin Haitao Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第4期190-222,共33页
To realize a hyperconnected smart society with high productivity,advances in flexible sensing technology are highly needed.Nowadays,flexible sensing technology has witnessed improvements in both the hardware performan... To realize a hyperconnected smart society with high productivity,advances in flexible sensing technology are highly needed.Nowadays,flexible sensing technology has witnessed improvements in both the hardware performances of sensor devices and the data processing capabilities of the device’s software.Significant research efforts have been devoted to improving materials,sensing mechanism,and configurations of flexible sensing systems in a quest to fulfill the requirements of future technology.Meanwhile,advanced data analysis methods are being developed to extract useful information from increasingly complicated data collected by a single sensor or network of sensors.Machine learning(ML)as an important branch of artificial intelligence can efficiently handle such complex data,which can be multi-dimensional and multi-faceted,thus providing a powerful tool for easy interpretation of sensing data.In this review,the fundamental working mechanisms and common types of flexible mechanical sensors are firstly presented.Then how ML-assisted data interpretation improves the applications of flexible mechanical sensors and other closely-related sensors in various areas is elaborated,which includes health monitoring,human-machine interfaces,object/surface recognition,pressure prediction,and human posture/motion identification.Finally,the advantages,challenges,and future perspectives associated with the fusion of flexible mechanical sensing technology and ML algorithms are discussed.These will give significant insights to enable the advancement of next-generation artificial flexible mechanical sensing. 展开更多
关键词 Flexible mechanical sensors machine learning Artificial intelligence Data processing
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Machine learning-guided accelerated discovery of structure-property correlations in lean magnesium alloys for biomedical applications
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作者 Sreenivas Raguraman Maitreyee Sharma Priyadarshini +5 位作者 Tram Nguyen Ryan McGovern Andrew Kim Adam J.Griebel Paulette Clancy Timothy P.Weihs 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2267-2283,共17页
Magnesium alloys are emerging as promising alternatives to traditional orthopedic implant materials thanks to their biodegradability,biocompatibility,and impressive mechanical characteristics.However,their rapid in-vi... Magnesium alloys are emerging as promising alternatives to traditional orthopedic implant materials thanks to their biodegradability,biocompatibility,and impressive mechanical characteristics.However,their rapid in-vivo degradation presents challenges,notably in upholding mechanical integrity over time.This study investigates the impact of high-temperature thermal processing on the mechanical and degradation attributes of a lean Mg-Zn-Ca-Mn alloy,ZX10.Utilizing rapid,cost-efficient characterization methods like X-ray diffraction and optical microscopy,we swiftly examine microstructural changes post-thermal treatment.Employing Pearson correlation coefficient analysis,we unveil the relationship between microstructural properties and critical targets(properties):hardness and corrosion resistance.Additionally,leveraging the least absolute shrinkage and selection operator(LASSO),we pinpoint the dominant microstructural factors among closely correlated variables.Our findings underscore the significant role of grain size refinement in strengthening and the predominance of the ternary Ca_(2)Mg_(6)Zn_(3)phase in corrosion behavior.This suggests that achieving an optimal blend of strength and corrosion resistance is attainable through fine grains and reduced concentration of ternary phases.This thorough investigation furnishes valuable insights into the intricate interplay of processing,structure,and properties in magnesium alloys,thereby advancing the development of superior biodegradable implant materials. 展开更多
关键词 Magnesium alloys machine learning Corrosion mechanical properties Rapid characterization
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Field-assisted machining of difficult-to-machine materials
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作者 Jianguo Zhang Zhengding Zheng +5 位作者 Kai Huang Chuangting Lin Weiqi Huang Xiao Chen Junfeng Xiao Jianfeng Xu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期39-89,共51页
Difficult-to-machine materials (DMMs) are extensively applied in critical fields such as aviation,semiconductor,biomedicine,and other key fields due to their excellent material properties.However,traditional machining... Difficult-to-machine materials (DMMs) are extensively applied in critical fields such as aviation,semiconductor,biomedicine,and other key fields due to their excellent material properties.However,traditional machining technologies often struggle to achieve ultra-precision with DMMs resulting from poor surface quality and low processing efficiency.In recent years,field-assisted machining (FAM) technology has emerged as a new generation of machining technology based on innovative principles such as laser heating,tool vibration,magnetic magnetization,and plasma modification,providing a new solution for improving the machinability of DMMs.This technology not only addresses these limitations of traditional machining methods,but also has become a hot topic of research in the domain of ultra-precision machining of DMMs.Many new methods and principles have been introduced and investigated one after another,yet few studies have presented a comprehensive analysis and summarization.To fill this gap and understand the development trend of FAM,this study provides an important overview of FAM,covering different assisted machining methods,application effects,mechanism analysis,and equipment design.The current deficiencies and future challenges of FAM are summarized to lay the foundation for the further development of multi-field hybrid assisted and intelligent FAM technologies. 展开更多
关键词 field-assisted machining difficult-to-machine materials materials removal mechanism surface integrity
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High-throughput studies and machine learning for design of β titanium alloys with optimum properties
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作者 Wei-min CHEN Jin-feng LING +4 位作者 Kewu BAI Kai-hong ZHENG Fu-xing YIN Li-jun ZHANG Yong DU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3194-3207,共14页
Based on experimental data,machine learning(ML) models for Young's modulus,hardness,and hot-working ability of Ti-based alloys were constructed.In the models,the interdiffusion and mechanical property data were hi... Based on experimental data,machine learning(ML) models for Young's modulus,hardness,and hot-working ability of Ti-based alloys were constructed.In the models,the interdiffusion and mechanical property data were high-throughput re-evaluated from composition variations and nanoindentation data of diffusion couples.Then,the Ti-(22±0.5)at.%Nb-(30±0.5)at.%Zr-(4±0.5)at.%Cr(TNZC) alloy with a single body-centered cubic(BCC) phase was screened in an interactive loop.The experimental results exhibited a relatively low Young's modulus of(58±4) GPa,high nanohardness of(3.4±0.2) GPa,high microhardness of HV(520±5),high compressive yield strength of(1220±18) MPa,large plastic strain greater than 30%,and superior dry-and wet-wear resistance.This work demonstrates that ML combined with high-throughput analytic approaches can offer a powerful tool to accelerate the design of multicomponent Ti alloys with desired properties.Moreover,it is indicated that TNZC alloy is an attractive candidate for biomedical applications. 展开更多
关键词 HIGH-THROUGHPUT machine learning Ti-based alloys diffusion couple mechanical properties wear behavior
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An Incentive Mechanism for Federated Learning:A Continuous Zero-Determinant Strategy Approach
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作者 Changbing Tang Baosen Yang +3 位作者 Xiaodong Xie Guanrong Chen Mohammed A.A.Al-qaness Yang Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期88-102,共15页
As a representative emerging machine learning technique, federated learning(FL) has gained considerable popularity for its special feature of “making data available but not visible”. However, potential problems rema... As a representative emerging machine learning technique, federated learning(FL) has gained considerable popularity for its special feature of “making data available but not visible”. However, potential problems remain, including privacy breaches, imbalances in payment, and inequitable distribution.These shortcomings let devices reluctantly contribute relevant data to, or even refuse to participate in FL. Therefore, in the application of FL, an important but also challenging issue is to motivate as many participants as possible to provide high-quality data to FL. In this paper, we propose an incentive mechanism for FL based on the continuous zero-determinant(CZD) strategies from the perspective of game theory. We first model the interaction between the server and the devices during the FL process as a continuous iterative game. We then apply the CZD strategies for two players and then multiple players to optimize the social welfare of FL, for which we prove that the server can keep social welfare at a high and stable level. Subsequently, we design an incentive mechanism based on the CZD strategies to attract devices to contribute all of their high-accuracy data to FL.Finally, we perform simulations to demonstrate that our proposed CZD-based incentive mechanism can indeed generate high and stable social welfare in FL. 展开更多
关键词 Federated learning(FL) game theory incentive mechanism machine learning zero-determinant strategy
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New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
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作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 General Relativity Quantum mechanics Space Time Dark Matter A New fundamental Constant “K”
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Contemporary Study for Detection of COVID-19 Using Machine Learning with Explainable AI
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作者 Saad Akbar Humera Azam +3 位作者 Sulaiman Sulmi Almutairi Omar Alqahtani Habib Shah Aliya Aleryani 《Computers, Materials & Continua》 SCIE EI 2024年第7期1075-1104,共30页
The prompt spread of COVID-19 has emphasized the necessity for effective and precise diagnostic tools.In this article,a hybrid approach in terms of datasets as well as the methodology by utilizing a previously unexplo... The prompt spread of COVID-19 has emphasized the necessity for effective and precise diagnostic tools.In this article,a hybrid approach in terms of datasets as well as the methodology by utilizing a previously unexplored dataset obtained from a private hospital for detecting COVID-19,pneumonia,and normal conditions in chest X-ray images(CXIs)is proposed coupled with Explainable Artificial Intelligence(XAI).Our study leverages less preprocessing with pre-trained cutting-edge models like InceptionV3,VGG16,and VGG19 that excel in the task of feature extraction.The methodology is further enhanced by the inclusion of the t-SNE(t-Distributed Stochastic Neighbor Embedding)technique for visualizing the extracted image features and Contrast Limited Adaptive Histogram Equalization(CLAHE)to improve images before extraction of features.Additionally,an AttentionMechanism is utilized,which helps clarify how the modelmakes decisions,which builds trust in artificial intelligence(AI)systems.To evaluate the effectiveness of the proposed approach,both benchmark datasets and a private dataset obtained with permissions from Jinnah PostgraduateMedical Center(JPMC)in Karachi,Pakistan,are utilized.In 12 experiments,VGG19 showcased remarkable performance in the hybrid dataset approach,achieving 100%accuracy in COVID-19 vs.pneumonia classification and 97%in distinguishing normal cases.Overall,across all classes,the approach achieved 98%accuracy,demonstrating its efficiency in detecting COVID-19 and differentiating it fromother chest disorders(Pneumonia and healthy)while also providing insights into the decision-making process of the models. 展开更多
关键词 COVID-19 detection deep neural networks support vector machine CXIs InceptionV3 VGG16 VGG19 t-SNE embedding CLAHE attention mechanism XAI
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An Expert System Based on Multi-reasoning Mechanism for Port Machine Diagnosis 被引量:1
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作者 Y. Ding G.L. Lin 《Journal of Shipping and Ocean Engineering》 2011年第2期101-108,共8页
Expert system plays an important role in port machine diagnosis, which aims at automatic equipment test for higher availability and efficiency of port operations. In this study, a port machine diagnosis expert system ... Expert system plays an important role in port machine diagnosis, which aims at automatic equipment test for higher availability and efficiency of port operations. In this study, a port machine diagnosis expert system is proposed based on multi-reasoning mechanism. Relying on the knowledge acquired from the experienced experts in the port machine engineering, the system builds a library of relative experience and a set of rules of reasoning and estimating. Multi-reasoning mechanism that simulates the decision-making process of domain experts is employed to achieve reliable diagnosis results. The reasoning machine integrates artificial neural network, uncertain decision making and decision tree, which complements each other by sustainable growing voting mechanism. The effect of this multi-reasoning mechanism is evaluated and validated by means of Matthew's Correlation Coefficient (MCC). The system incorporating the mechanism is successfully designed, implemented and applied in Shanghai Port. 展开更多
关键词 Port machine diagnosis multi-reasoning mechanism ANN uncertain decision making decision tree.
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DYNAMICS OF THE LOOPER DRIVE MECHANISM ON A BLIND STITCHING MACHINE
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作者 项靖安 史荣生 《Journal of China Textile University(English Edition)》 EI CAS 1990年第4期54-62,共9页
The looper drive mechanism is a main moving part in the blind stitching machine, which is aspatial 5 bar RRRSR linkage. In this paper, a dynamic analysis of the looper drive mechanism is made by means of the ma-trix m... The looper drive mechanism is a main moving part in the blind stitching machine, which is aspatial 5 bar RRRSR linkage. In this paper, a dynamic analysis of the looper drive mechanism is made by means of the ma-trix method. Two methods are adopted in the calculation of the shaking force and shaking moment, one isdone by the constraint reaction of the flame-connected kinematic parts; the other is the inertialforces of all moving links. 展开更多
关键词 BLIND STITCHING machine LOOPER drive mechanism SHAKING force SHAKING MOMENT constraint reaction
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Determination of the workspace of a new coordinate-measuring machine using parallel-link mechanism
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作者 刘得军 黄庆成 +2 位作者 叶东 车仁生 周琳 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第2期147-154,共8页
Presents the detailed algorithm established for determination of workspace for a 3-DOF coordinate measuring machine using parallel link mechanism by constructing the inverse kinematic model first and then reviewing th... Presents the detailed algorithm established for determination of workspace for a 3-DOF coordinate measuring machine using parallel link mechanism by constructing the inverse kinematic model first and then reviewing the physical and kinematical constraints from the structural characteristics of the parallel link mechanism, and discusses the actual geometries of workspace and the factors having effect on workspace through computer simulation thereby providing necessary theoretical basis for the research and development of coordinate measuring machines using parallel link mechanism. 展开更多
关键词 coordinate measuring machine WORKSPACE parallel link mechanism three degrees of freedom spatial coordinate
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The First Student International Olympiad on Mechanism and Machine SciencemThe Challenge in MMS Education
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作者 Veniamin Goldfarb Eduard Krylov Alexander Elenskii 《Journal of Mechanics Engineering and Automation》 2013年第3期152-158,共7页
One of important tasks of IFToMM is attraction of youth attention to profound study of mechanism and machine science. To solve this task, special youth programs are developed, various discounts are provided for young ... One of important tasks of IFToMM is attraction of youth attention to profound study of mechanism and machine science. To solve this task, special youth programs are developed, various discounts are provided for young researchers' participation in IFToMM congresses and conferences. A new progressive type of such an activity is organization of Student International Olympiads (SIO) on Mechanism and Machine Science (MMS) which can be considered a new advantageous form of MMS study. The paper describes experiences of organization and holding the first SIO MMS, which took place on April 19-21,2011 in Izhevsk (Russia) at Izhevsk State Technical University. 展开更多
关键词 mechanism and machine science EDUCATION student international Olympiad.
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Laser machining fundamentals:micro,nano,atomic and close-to-atomic scales 被引量:6
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作者 Jinshi Wang Fengzhou Fang +4 位作者 Haojie An Shan Wu Huimin Qi Yuexuan Cai Guanyu Guo 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第1期125-151,共27页
With the rapid development in advanced industries,such as microelectronics and optics sectors,the functional feature size of devises/components has been decreasing from micro to nanometric,and even ACS for higher perf... With the rapid development in advanced industries,such as microelectronics and optics sectors,the functional feature size of devises/components has been decreasing from micro to nanometric,and even ACS for higher performance,smaller volume and lower energy consumption.By this time,a great many quantum structures are proposed,with not only an extreme scale of several or even single atom,but also a nearly ideal lattice structure with no material defect.It is almost no doubt that such structures play critical role in the next generation products,which shows an urgent demand for the ACSM.Laser machining is one of the most important approaches widely used in engineering and scientific research.It is high-efficient and applicable for most kinds of materials.Moreover,the processing scale covers a huge range from millimeters to nanometers,and has already touched the atomic level.Laser–material interaction mechanism,as the foundation of laser machining,determines the machining accuracy and surface quality.It becomes much more sophisticated and dominant with a decrease in processing scale,which is systematically reviewed in this article.In general,the mechanisms of laser-induced material removal are classified into ablation,CE and atomic desorption,with a decrease in the scale from above microns to angstroms.The effects of processing parameters on both fundamental material response and machined surface quality are discussed,as well as theoretical methods to simulate and understand the underlying mechanisms.Examples at nanometric to atomic scale are provided,which demonstrate the capability of laser machining in achieving the ultimate precision and becoming a promising approach to ACSM. 展开更多
关键词 laser machining mechanism atomic and close-to-atomic scale manufacturing ACSM manufacturing III
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Spatial distribution and failure mechanism of water-induced landslides in the reservoir areas of Southwest China 被引量:3
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作者 Mingliang Chen Xingguo Yang Jiawen Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期442-456,共15页
Water-induced landslides in hydropower reservoirs pose a great threat to both project operation and human life.This paper examines three large reservoirs in Sichuan Province,China.Field surveys,site monitoring data an... Water-induced landslides in hydropower reservoirs pose a great threat to both project operation and human life.This paper examines three large reservoirs in Sichuan Province,China.Field surveys,site monitoring data analyses and numerical simulations are used to analyze the spatial distribution and failure mechanisms of water-induced landslides in reservoir areas.First,the general rules of landslide development in the reservoir area are summarized.The first rule is that most of the landslides have rear edge elevations of 100e500 m above the normal water level of the reservoir,with volumes in the range of 106 e107 m 3.When the volume exceeds a certain amount,the number of sites at which the landscape can withstand landslides is greatly reduced.Landslide hazards mainly occur in the middle section of the reservoir and less in the annex of the dam site and the latter half of the reservoir area.The second rule is that sedimentary rocks such as sandstone are more prone to landslide hazards than other lithologies.Then,the failure mechanism of changes in the water level that reduces the stability of the slope composed of different geomaterials is analyzed by a proposed slope stability framework that considers displacement and is discussed with the monitoring results.Permeability is an essential parameter for understanding the diametrically opposed deformation behavior of landslides experiencing filling-drawdown cycles during operation.This study seeks to provide inspiration to subsequent researchers,as well as guidance to technicians,on landslide prevention and control in reservoir areas. 展开更多
关键词 Water-induced landslide Hydropower reservoir Spatial distribution fundamental control Failure mechanism
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Design and Analysis of a Novel Shoulder Exoskeleton Based on a Parallel Mechanism 被引量:2
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作者 Lianzheng Niu Sheng Guo +2 位作者 Majun Song Yifan Wu Haibo Qu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第2期261-278,共18页
Power-assisted upper-limb exoskeletons are primarily used to improve the handling efficiency and load capacity.However,kinematic mismatch between the kinematics and biological joints is a major problem in most existin... Power-assisted upper-limb exoskeletons are primarily used to improve the handling efficiency and load capacity.However,kinematic mismatch between the kinematics and biological joints is a major problem in most existing exoskeletons,because it reduces the boosting effect and causes pain and long-term joint damage in humans.In this study,a shoulder augmentation exoskeleton was designed based on a parallel mechanism that solves the shoulder dislocation problem using the upper arm as a passive limb.Consequently,the human–machine synergy and wearability of the exoskeleton system were improved without increasing the volume and weight of the system.A parallel mechanism was used as the structural body of the shoulder joint exoskeleton,and its workspace,dexterity,and stiffness were analyzed.Additionally,an ergonomic model was developed using the principle of virtual work,and a case analysis was performed considering the lifting of heavy objects.The results show that the upper arm reduces the driving force requirement in coordinated motion,enhances the load capacity of the system,and achieves excellent assistance. 展开更多
关键词 Upper limb exoskeleton Parallel mechanism Human–machine compatibility DYNAMICS
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Micro Model of Carbon Fiber/Cyanate Ester Composites and Analysis of Machining Damage Mechanism 被引量:3
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作者 Haitao Liu Jie Lin +1 位作者 Yazhou Sun Jinyang Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期198-208,共11页
Machining damage occurs on the surface of carbon fiber reinforced polymer (CFRP) composites during processing. In the current simulation model of CFRP, the initial defects on the carbon fiber and the periodic random d... Machining damage occurs on the surface of carbon fiber reinforced polymer (CFRP) composites during processing. In the current simulation model of CFRP, the initial defects on the carbon fiber and the periodic random distribution of the reinforcement phase in the matrix are not considered in detail, which makes the characteristics of the cutting model significantly different from the actual processing conditions. In this paper, a novel three-phase model of carbon fiber/cyanate ester composites is proposed to simulate the machining damage of the composites. The periodic random distribution of the carbon fiber reinforced phase in the matrix was realized using a double perturbation algorithm. To achieve the stochastic distribution of the strength of a single carbon fiber, a novel method that combines the Weibull intensity distribution theory with the Monte Carlo method is presented. The mechanical properties of the cyanate matrix were characterized by fitting the stress-strain curves, and the cohesive zone model was employed to simulate the interface. Based on the model, the machining damage mechanism of the composites was revealed using finite element simulations and by conducting a theoretical analysis. Furthermore, the milling surfaces of the composites were observed using a scanning electron microscope, to verify the accuracy of the simulation results. In this study, the simulations and theoretical analysis of the carbon fiber/cyanate ester composite processing were carried out based on a novel three-phase model, which revealed the material failure and machining damage mechanism more accurately. 展开更多
关键词 Carbon fiber reinforced polymer COMPOSITES MICRO simulation model machinING damage mechanism MILLING and observation experiment Theoretical ANALYSIS
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Interpretable hybrid machine learning demystifies the degradation of practical lithium-sulfur batteries
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作者 Zhi Wei Seh 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期54-55,共2页
The ever-increasing future demands of electrification and grid storage have spurred continued research to develop rechargeable battery chemistries for reliable energy storage[1].Beyond current lithium-ion batteries,li... The ever-increasing future demands of electrification and grid storage have spurred continued research to develop rechargeable battery chemistries for reliable energy storage[1].Beyond current lithium-ion batteries,lithium–sulfur battery represents a promising system due to its high energy density(2600 Wh kg^(-1))and low material cost[2]. 展开更多
关键词 machine learning Lithium-sulfur batteries Battery prognosis Capacity degradation mechanism
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