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Slope stability prediction based on a long short-term memory neural network:comparisons with convolutional neural networks,support vector machines and random forest models 被引量:6
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作者 Faming Huang Haowen Xiong +4 位作者 Shixuan Chen Zhitao Lv Jinsong Huang Zhilu Chang Filippo Catani 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第2期83-96,共14页
The numerical simulation and slope stability prediction are the focus of slope disaster research.Recently,machine learning models are commonly used in the slope stability prediction.However,these machine learning mode... The numerical simulation and slope stability prediction are the focus of slope disaster research.Recently,machine learning models are commonly used in the slope stability prediction.However,these machine learning models have some problems,such as poor nonlinear performance,local optimum and incomplete factors feature extraction.These issues can affect the accuracy of slope stability prediction.Therefore,a deep learning algorithm called Long short-term memory(LSTM)has been innovatively proposed to predict slope stability.Taking the Ganzhou City in China as the study area,the landslide inventory and their characteristics of geotechnical parameters,slope height and slope angle are analyzed.Based on these characteristics,typical soil slopes are constructed using the Geo-Studio software.Five control factors affecting slope stability,including slope height,slope angle,internal friction angle,cohesion and volumetric weight,are selected to form different slope and construct model input variables.Then,the limit equilibrium method is used to calculate the stability coefficients of these typical soil slopes under different control factors.Each slope stability coefficient and its corresponding control factors is a slope sample.As a result,a total of 2160 training samples and 450 testing samples are constructed.These sample sets are imported into LSTM for modelling and compared with the support vector machine(SVM),random forest(RF)and convo-lutional neural network(CNN).The results show that the LSTM overcomes the problem that the commonly used machine learning models have difficulty extracting global features.Furthermore,LSTM has a better prediction performance for slope stability compared to SVM,RF and CNN models. 展开更多
关键词 Slope stability prediction Long short-term memory Deep learning Geo-Studio software Machine learning model
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Climate change and permafrost stability in the eastern Canada Cordillera:The results of 33 years of measurements 被引量:3
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作者 Stuart A.Harris 《Research in Cold and Arid Regions》 2009年第5期381-403,共23页
Over the last 33 years,a network of climate stations has been set up at high altitude mountain permafrost sites from Plateau Mountain near Claresholm,Alberta,north to Sheldon Lake on the North Canol Road in the Yukon.... Over the last 33 years,a network of climate stations has been set up at high altitude mountain permafrost sites from Plateau Mountain near Claresholm,Alberta,north to Sheldon Lake on the North Canol Road in the Yukon.Taken together with the data from the US National Weather Service and the Canadian Atmospheric Environment Service,the results indicate a cooling of mean annual air temperature south of Calgary,no significant change in Calgary,a slight warming at Jasper,and a major warming at Summit Lake,west of Fort Nelson.In contrast,the south eastern and central Yukon show only a minor warming trend that lies well within the limits of a sixty-year record measured by the Canadian Atmospheric Environment Service.Along the Mackenzie valley and on the North Slope of Alaska,the mean annual air temperature is rising.Permafrost is aggrading on Plateau Mountain,degrading at Summit Lake,and appears to be stable in southern Yukon and southern Alaska.This is in contrast to the warming occurring on the Arctic coastal plain and along the Mackenzie valley.It therefore appears that changes in climate vary considera-bly from place to place,and even where warming may occur,it may not continue indefinitely.There has been a northward shift of the arctic front due to a weakening of air pressure in the Yukon and Alaska relative to the continental tropical(cT) and maritime polar(mT) air masses to the south.Any actual changes that may be occurring appear to undergo amplification along the Mackenzie valley and Arctic coastal plain and reduction by buffering in the interior Yukon and Alaskan mountains,a result of mi-cro-environmental factors.Continued,careful monitoring of the climate is required and needs to be expanded in the National Parks in the mountains in order to provide data on the changes that may be taking place.Such measurements can provide a sound basis for interpreting ecological and other climate-related data.The existing climate models are not working satisfactorily because we do not know enough about the causes and processes involved in climate change.Improved results can indicate where best to site structures such as pipelines so as to minimize maintenance costs.Models may also help explain why certain areas such as Beringia,which saw reduced climate change,acted as important refugia during the glaciations. 展开更多
关键词 PERMAFROST stability long-term measurement climate change the Eastern Canada Cordillera
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Pre-evaluation on stability of proposed expressway embankment with existing geothermal regulation measures in permafrost regions 被引量:2
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作者 LUO Xiao-xiao MA Qin-guo JIANG Hai-qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第1期264-283,共20页
Embankment stability is the primary problem for the expressway construction in permafrost regions.The proposed Qinghai-Tibet Expressway(QTE)is planned to construct along the Qinghai-Tibet Project Corridor.Confronted w... Embankment stability is the primary problem for the expressway construction in permafrost regions.The proposed Qinghai-Tibet Expressway(QTE)is planned to construct along the Qinghai-Tibet Project Corridor.Confronted with harsh environmental condition and intense heat exchange between earth and atmosphere,it is necessary to predict and evaluate the stability of the proposed QTE.In this study,the factors affecting the embankment stability are analyzed firstly.And then,a scheme for the stability evaluation of the embankment is established.Finally,the evaluation scheme is used for the pre-evaluation of the stability for the proposed QTE with different geothermal regulation measures(GRMs).The results indicate that the influencing factors include climatic environment,permafrost property,engineering condition and geological condition,and among them,engineering condition and permafrost property are the main influence factors for embankment stability.The stability of the proposed QTE varies greatly in the different geomorphological regions.The application effect and contribution to embankment stability of the existing GRMs are different,and using GRMs cannot completely overcome the influence of various factors on expressway stability.In the construction process,different GRMs should be adopted depending on the geomorphological environment where the embankment is located to ensure the embankment stability. 展开更多
关键词 PERMAFROST expressway embankment influencing factor stability evaluation geothermal regulation measures
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Global exponentially stability for time-delay and time-varying measure large scale systems with impulsive effects
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作者 刘云龙 高存臣 +1 位作者 李云艳 刘现明 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期175-180,共6页
The global exponentially stability was studied for time-delay and time-varying measure large scale systems with impulsive effects. Firstly, the concepts are drawn for the functional category. Secondly, some sufficient... The global exponentially stability was studied for time-delay and time-varying measure large scale systems with impulsive effects. Firstly, the concepts are drawn for the functional category. Secondly, some sufficient conditions of the uniformly stability and the global exponentially stability are given for the above systems through defining a Lyapunov function of the weighting sum of the variable absolute by using the Lyapunov function method and the comparison principle. At the same time, the new conclusion of stability of these systems is more universal and contains the existing results. Finally, an example is given to illustrate the feasibility and validity of the obtained results. 展开更多
关键词 distributional DERIVATIVE TIME-DELAY measure large scale systems IMPULSIVE GLOBAL EXPONENTIALLY stability
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STABILITY CRITERIA IN TERMS OF TWO MEASURES FOR DELAY DIFFERENTIAL EQUATIONS
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作者 KOU Chun-hai(寇春海) +1 位作者 ZHANG Shu-nian(张书年) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第3期311-320,共10页
By using the variational Liapunov method, stability properties in terms of two measures for delay differential equations are discussed. In the case that the unperturbed systems are ordinary differential systems, emplo... By using the variational Liapunov method, stability properties in terms of two measures for delay differential equations are discussed. In the case that the unperturbed systems are ordinary differential systems, employing auxiliary measure h*(t, x), criteria on nonuniform and uniform stability in terms of two measures for delay differential equations are established. 展开更多
关键词 delay differential equations variational Liapunov method stability two measures
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Stability and boundedness in terms of two measures for nonlinear impulsive control systems
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作者 Qiang XI 《控制理论与应用(英文版)》 EI 2009年第3期243-247,共5页
In this paper we study stability and boundedness in terms of two measures for impulsive control systems. By using variational Lyapunov method, a new variational comparison principle and some criteria on stability and ... In this paper we study stability and boundedness in terms of two measures for impulsive control systems. By using variational Lyapunov method, a new variational comparison principle and some criteria on stability and boundedness are obtained. An example is presented to illustrate the efficiency of proposed result. 展开更多
关键词 stability BOUNDEDNESS Impulsive control systems Variational Lyapunov method Two measures
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Transient Stability Analysis Using Transmission Line Measurement
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作者 蔡国伟 程浩忠 +1 位作者 陈家荣 王承民 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第2期29-35,共7页
The novel quantitative assessment method using transmission line measurement was developed. A new style of stability criterion was suggested which is based on the line measurement. The stability indices for lines, cut... The novel quantitative assessment method using transmission line measurement was developed. A new style of stability criterion was suggested which is based on the line measurement. The stability indices for lines, cutsets and power system according to features of transient energy in the lines were given, which not only provide a reliable and accurate assessment of the transient stability of power system, but also can be used to assess the effect of lines and cutsets on the transient stability and identify the weak transmission segment. Examples were presented by simulation on the IEEE-39 buses test system. 展开更多
关键词 power system transient stability local network measurement stability criterion line stability index cutset stability index
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Research About Measures of Enhancing Stability of Competitive Strategic Alliance
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作者 JI Hong HUANG Yu CAO Zhichao 《Chinese Business Review》 2011年第12期1191-1198,共8页
With the global economy and the intensification of market competition, more and more enterprises in the same industry to establish a new alliance---competitive strategic alliance. Competitive strategic alliance is not... With the global economy and the intensification of market competition, more and more enterprises in the same industry to establish a new alliance---competitive strategic alliance. Competitive strategic alliance is not only in the strategic choice of the existence of a potential to create value, but also the existence of synergy. Competition and cooperation between the two conflicting complex logic relations coexist in the competitive strategic alliances (CSA). Therefore maintaining the relative stability of alliance is the premise and necessary condition of alliance to success. In this paper, on the basis of the literature review, we discuss the significance and principles of improving CSA's stability; in the way of case analysis and expert interviews construct the hierarchy analysis model of improving CSA's stability; and then further put forward a series of measures which can maintain the CSA's stability, such as strengthen the ability of technological innovation, protection and development of the core ability of the enterprise, to develop a coherent strategy alliance target, choose a suitable alliance partner, coordinate the corporate culture between partners, establish alliance risk prevention mechanism, and so on. It will provide theoretical support and practical guidance to relevant departments and relevant personnel in policy decision-making and problem-solving 展开更多
关键词 COMPETITIVE competitive strategic alliance (CSA) stability measures
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Stability Analysis and Measure Study of Tobacco Farmers in the Mountainous Area of Western Hubei
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作者 Fanwen FENG Benfu LIU +4 位作者 Jing HUANG Gaohang CHEN Shenghui TUO Yongjun CHEN Yong WANG 《Asian Agricultural Research》 2022年第11期21-23,30,共4页
Through the investigation,this paper analyzes the important restricting factors for the tobacco farmers in Enshi Badong mountainous area from 2018 to 2021,including the age structure,the loss situation,the number of y... Through the investigation,this paper analyzes the important restricting factors for the tobacco farmers in Enshi Badong mountainous area from 2018 to 2021,including the age structure,the loss situation,the number of years of planting tobacco,the scale of planting tobacco and the benefit of planting tobacco.This paper puts forward some corresponding measures and suggestions,such as cultivating the team of professional tobacco farmers,establishing the team of young tobacco farmers,expanding professional services,developing"tobacco plus"diversified industries,and popularizing suitable agricultural machinery in mountainous areas in order to effectively improve the stability of the team of tobacco farmers. 展开更多
关键词 Mountainous area Tobacco farmers stability measures
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INVARIANT MANIFOLDS AND THEIR STABILITY IN A THREE-DIMENSIONAL MEASURE-PRESERVING MAPPING SYSTEMS
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作者 刘杰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第10期943-950,共8页
In the paper researches on a three-dimensional measure-preserving mappingsystem are made,which is the three-dimensional extension of the Keplerian mapping.With formal series method the expressions of the invariant cur... In the paper researches on a three-dimensional measure-preserving mappingsystem are made,which is the three-dimensional extension of the Keplerian mapping.With formal series method the expressions of the invariant curves and invarianttori are obtained,Finally the stability of these in variant manifolds is also discussed. 展开更多
关键词 measure-preserving mapping CHAOS invariant manifold stability
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INVARIANT MANIFOLDS AND THEIR STABILITY IN A THREE-DIMENSIONAL MEASURE-PRESERVING MAPPING SYSTEMS
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作者 刘杰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第5期943-950,共8页
In the paper researches on a three-dimensional measure-preserving mappingsystem are made,which is the three-dimensional extension of the Keplerian mapping.With formal series method the expressions of the invariant cur... In the paper researches on a three-dimensional measure-preserving mappingsystem are made,which is the three-dimensional extension of the Keplerian mapping.With formal series method the expressions of the invariant curves and invarianttori are obtained,Finally the stability of these in variant manifolds is also discussed. 展开更多
关键词 measure-preserving mapping chaos invariant manifold stability
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Stability Monitoring and Control of Generation Based on the Synchronized Measurements in Nodes of Its Connection
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作者 Alexander Fishov Maria Shiller +1 位作者 Anton Dekhterev Vladimir Fishov 《Journal of Energy and Power Engineering》 2015年第1期59-67,共9页
Synchronized distributed measurements of mode parameters create a technical feasibility for development and implementing new technologies of control the mode stability and the admissibility of EPS (electric power sys... Synchronized distributed measurements of mode parameters create a technical feasibility for development and implementing new technologies of control the mode stability and the admissibility of EPS (electric power system) mode. Discussion will focus on different models obtained from data synchronized measurements for operational and automatic emergency control without EPS being totally controlled. According to the proposed technology, the generator's output power restrictions are determined in real-time by the terms a static stability using the generators' mode model as a multipole with connection nodes of generators' electromotive forces (the matrix of SMA (self and mutual admittances) of electromotive forces of generators). Potential applications of the technology are distribution network with the main substation and generators of commensurable capacity, and transmission network with large power plants (generators) distributed into the network. The one-level control system for all of generators with defining the generator's power limits relative to the main substation is implemented in the first case. In the second case, the two-level control system is brought in, based on the separation of large and small generation motion. The results of the method and technology efficiency verification are shown in the paper, by both computer simulations of the power system modes and its physical model. 展开更多
关键词 Power system static stability synchronized measurements normal mode transient mode post emergency mode matrix of self and mutual admittances.
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Stability Analysis of Contact Scanning Probe for Micro/Nano Coordinate Measuring Machine 被引量:2
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作者 李瑞君 范光照 +3 位作者 钱剑钊 黄强先 龚伟 苗晋伟 《纳米技术与精密工程》 EI CAS CSCD 2012年第2期125-131,共7页
关键词 微纳米三坐标测量机 扫描探头 稳定性分析 传感哭喊中
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Digital image stabilization system based on inertial measurement module 被引量:1
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作者 金锋 李田 《Journal of Beijing Institute of Technology》 EI CAS 2013年第2期222-227,共6页
In order to stabilize the video module to build digital image stabilization image sequence, a method of using inertial measurement system is proposed. Through applying real-time attitude in- formation of the camera th... In order to stabilize the video module to build digital image stabilization image sequence, a method of using inertial measurement system is proposed. Through applying real-time attitude in- formation of the camera that obtained by high-precision attitude sensor to estimate the image motion vector and then to compensate for image, the purpose of stabilizing the image sequence can be a- chieved. Experiments demonstrate that this method has a high image stabilization precision, and the up to 16 frame/s video output rate completely meets the real-time requirements. 展开更多
关键词 inertial measurement module digital image stabilization system motion vector real- time
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Improvement of the short-term stability of atomic fountain clock with state preparation by two-laser optical pumping
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作者 Lei Han Fang Fang +4 位作者 Wei-Liang Chen Kun Liu Shao-Yang Dai Ya-Ni Zuo and Tian-Chu Li 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期272-276,共5页
To improve the signal to noise ratio(SNR)and the short-term stability of cesium atomic fountain clocks,the work of two-laser optical pumping is presented theoretically and experimentally.The short-term stability of th... To improve the signal to noise ratio(SNR)and the short-term stability of cesium atomic fountain clocks,the work of two-laser optical pumping is presented theoretically and experimentally.The short-term stability of the NIM6 fountain clock has been improved by preparing more cold atoms in the|F=4,m_(F)=0>clock state with a shortened cycle time.Two π-polarized laser beams overlapped in the horizontal plane have been applied after launching,one is resonant with|F=4>→|F′=4>transition and the other is resonant with|F=3>→|F′=4>transition.With optical pumping,the population accumulated in the|m_(F)=0>clock state is improved from 11%to 63%,and the detection signal is increased by a factor of 4.2,the SNR of the clock transition probability and the short-term stability are also improved accordingly. 展开更多
关键词 optical pumping atomic fountain clock SPIN-POLARIZATION short-term stability
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Double-dot interferometer for quantum measurement of Majorana qubits and stabilizers
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作者 Kai Zhou Cheng Zhang +1 位作者 Lupei Qin Xin-Qi Li 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第1期142-150,共9页
Motivated by the need of quantum measurement of Majorana qubits and surface-code stabilizers, we analyze the performance of a double-dot interferometer under the influence of environment noise. The double-dot setup de... Motivated by the need of quantum measurement of Majorana qubits and surface-code stabilizers, we analyze the performance of a double-dot interferometer under the influence of environment noise. The double-dot setup design allows accounting for the full multiple tunneling process between the dots through the Majorana island, within a master equation approach. In the co-tunneling regime, which results in a Majorana-mediated effective coupling between the dots, the master equation approach allows us to obtain analytic solutions for the measurement currents. The measurement quality,characterized by figures of merit such as the visibility of measurement signals, is carried out in regard to the unusual decoherence effect rather than ‘which-path’ dephasing. The results obtained in this work are expected to be useful for future experiments of Majorana qubit and stabilizer measurements. 展开更多
关键词 Majorana qubits stabilIZERS quantum measurements
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Precipitation and stability of reversed austenite in 9Ni steel 被引量:14
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作者 Yue-hui Yang Qing-wu Cai Di Tang Hui-bin Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第5期587-595,共9页
A new method was used to analyze the factors affecting the precipitation of reversed austenite during tempering. The samples were kept at various tempering temperatures for 10 min and their length changes were recorde... A new method was used to analyze the factors affecting the precipitation of reversed austenite during tempering. The samples were kept at various tempering temperatures for 10 min and their length changes were recorded. Then, the precipitation of reversed austenite which led to the length reduction was shown by thermal expansion curves. The results show that the effects of process parameters on the precipitation of reversed austenite can be determined more accurately by this method than by X-ray diffraction. When the quenching and tempering process is adopted, both the lower quenching temperature and higher tempering temperature can promote the precipitation of reversed austenite during tempering; and when the quenching, lamellarizing, and tempering process is used, intercritical quenching is considered beneficial to the precipitation of reversed austenite in the subsequent tempering because of Ni segregation during holding at the intercritical temperature. 展开更多
关键词 cryogenic equipment low carbon steel reversed austenite PRECIPITATION stability thermal expansion measurement
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Convolution Neural Network-based Load Model Parameter Selection Considering Short-term Voltage Stability
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作者 Ying Wang Chao Lu Xinran Zhang 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2024年第3期1064-1074,共11页
The recently proposed ambient signal-based load modeling approach offers an important and effective idea to study the time-varying and distributed characteristics of power loads.Meanwhile,it also brings new problems.S... The recently proposed ambient signal-based load modeling approach offers an important and effective idea to study the time-varying and distributed characteristics of power loads.Meanwhile,it also brings new problems.Since the load model parameters of power loads can be obtained in real-time for each load bus,the numerous identified parameters make parameter application difficult.In order to obtain the parameters suitable for off-line applications,load model parameter selection(LMPS)is first introduced in this paper.Meanwhile,the convolution neural network(CNN)is adopted to achieve the selection purpose from the perspective of short-term voltage stability.To begin with,the field phasor measurement unit(PMU)data from China Southern Power Grid are obtained for load model parameter identification,and the identification results of different substations during different times indicate the necessity of LMPS.Meanwhile,the simulation case of Guangdong Power Grid shows the process of LMPS,and the results from the CNNbased LMPS confirm its effectiveness. 展开更多
关键词 Ambient signal CNN field PMU data load model parameter selection short-term voltage stability
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Non-destructive Measurement of Magnetic Properties of Claw Pole 被引量:2
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作者 Chengliang Hu Xuejiao Bai +2 位作者 Minjun Tang Xiaofeng Tang Zhen Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第5期23-33,共11页
The magnetic properties of the claw pole have a direct effect on the output power of a generator Many methods can be used to measure these magnetic properties,each with its own advantages,but an important shortcoming ... The magnetic properties of the claw pole have a direct effect on the output power of a generator Many methods can be used to measure these magnetic properties,each with its own advantages,but an important shortcoming is that all are destructive.In this study,a new non-destructive method to measure the magnetic properties of claw pole was proposed and a corresponding testing set-up was designed.A finite-element model was constructed to simulate the measurement process.Results proved that the measured magnetization-like curves had good agreement with the trend of the input magnetic curves and the effect of the positioning error in the measuring process could be neglected.To further validate the new method,seven types of claw poles of different materials subjected to different heat-treatment processes were forged and tested by both the new method and the conventional ring-sample method.Compared with the latter,the new method showed better consistency,relatively higher accuracy,and much stronger stability of measurement results;however,its sensitivity needs to be improved.The effects of material compositions and heat-treatment parameters on the magnetic properties of the claw pole were briefly analyzed. 展开更多
关键词 CLAW POLE MAGNETIC property measurement RING SAMPLE Accuracy stability
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Numerical analysis of stability for mined-out area in multi-field coupling 被引量:5
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作者 罗周全 谢承煜 +3 位作者 周吉明 贾楠 刘晓明 徐海 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期669-675,共7页
There were differences between real boundary and blast hole controlling boundary of irregular mined-out area in underground metal mines. There were errors in numerical analysis of stability for goaf, if it was analyze... There were differences between real boundary and blast hole controlling boundary of irregular mined-out area in underground metal mines. There were errors in numerical analysis of stability for goaf, if it was analyzed as regular 3D mined-out area and the influence of coupling stress-seepage-disturbance was not considered adequately. Taking a lead zinc mine as the background, the model was built by the coupling of Surpac and Midas-Gts based on the goaf model precisely measured by CMS.According to seepage stress fundamental equations based on the equivalent continuum mechanical and the theory about equivalent load of dynamic disturbance in deep-hole blasting, the stability of mined-out area under multi-field coupling of stress-seepage-dynamic disturbance was numerically analyzed. The results show that it is more consistent between the numerical analysis model based on the real model of irregular 3D shape goaf and the real situation, which could faithfully reappear the change rule of stress–strain about the surrounding rock under synthetic action of blasting dynamic loading and the seepage pressure. The mined-out area multi-field coupling formed by blasting excavation is stable. Based on combination of the advantages of the CMS,Surpac and Midas-Gts, and fully consideration of the effects of multi-field coupling, the accurate and effective way could be provided for numerical analysis of stability for mined-out area. 展开更多
关键词 mined-out area measured actually multi-field coupling stress-seepage-disturbance stability for mined-out area
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