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圆柱贮箱中液体晃动的模部分析 被引量:6
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作者 苟兴宇 王本利 +1 位作者 马兴瑞 黄怀德 《宇航学报》 EI CAS CSCD 北大核心 1998年第1期72-76,共5页
本文对圆柱贮箱中液体的晃动问题进行了精细研究,提出了模部及模部分析的新概念。在此基础上,文章研究了在不同接触角假设下的模部正交性问题,对传统的圆柱贮箱中液体的受迫晃动理论作了本质分析,并从速度势函数z模部的角度分析了... 本文对圆柱贮箱中液体的晃动问题进行了精细研究,提出了模部及模部分析的新概念。在此基础上,文章研究了在不同接触角假设下的模部正交性问题,对传统的圆柱贮箱中液体的受迫晃动理论作了本质分析,并从速度势函数z模部的角度分析了深箱问题的实质。 展开更多
关键词 液体晃动 模部分析 推进剂箱
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小Bond数条件下圆柱贮箱中液体晃动的模部分析 被引量:3
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作者 苟兴宇 王本利 +2 位作者 马兴瑞 黄怀德 李铁寿 《应用数学和力学》 EI CSCD 北大核心 1999年第9期913-918,共6页
运用模部分析方法考察了小 Bond 数条件下圆柱贮箱中弯曲静液面对液体晃动模态的重构作用· 研究表明,圆柱贮箱中的液体作小幅晃动时,参与晃动的各阶基本模态的正交性若仅由 Bessel 模部来给出,则弯曲静液面将使各阶... 运用模部分析方法考察了小 Bond 数条件下圆柱贮箱中弯曲静液面对液体晃动模态的重构作用· 研究表明,圆柱贮箱中的液体作小幅晃动时,参与晃动的各阶基本模态的正交性若仅由 Bessel 模部来给出,则弯曲静液面将使各阶模态加权耦合,形成新的特征模态;参与晃动的各阶基本模态的正交性若由三角函数模部来给出,则弯曲静液面将独立改变各阶模态的固有频率,各阶模态之间不耦合· 运用新的重构模态来研究圆柱贮箱中液体的横向受迫晃动,给出了其模态选择特征· 展开更多
关键词 Bond数 模部分析 圆柱贮箱 液体晃动
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Frictional contact algorithm study on the numerical simulation of large deformations in deep soft rock tunnels 被引量:5
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作者 GUO Hongyun CHEN Xin +2 位作者 HE Manchao XI Shouzhong TANG Juzhen 《Mining Science and Technology》 EI CAS 2010年第4期524-529,共6页
There exist three types of nonlinear problems in large deformation processes of deep softrock engineering, i.e., nonlin- earity caused by material, geometrical and contact boundary. In this paper, the numerical method... There exist three types of nonlinear problems in large deformation processes of deep softrock engineering, i.e., nonlin- earity caused by material, geometrical and contact boundary. In this paper, the numerical method to tackle the nonlinear eontact and large deformation problem in A Software on Large Deformation Analysis for Soft Rock Engineering at Great Depth was presented. In the software, based on Lagrange multiplier method and Coulomb friction law, kinematic constraints on contact boundaries were introduced in functional function, and the finite element equations was established for two incremental large deformation analyses models, polar decomposition model and additive decomposition model. For every incremental loading step, by searching for the contact points in the potential contact interfaces (the excavation boundaries), the Lagrange multipliers, i.e., contact forces are cal- culated iteratively by Gauss-Seidel method, and justified through satisfy the inequalities of static constraint on contact boundaries. With the software, large deformation and frictional contact of a transport roadway were analyzed numerically by the two models. The numerical examples demonstrated the efficiency of the method used in the software. 展开更多
关键词 deep softrock engineering large deformation frictional contact Lagrange multiplier method FEM
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Development of Three Risk Assessment Models for Deoxynivalenol and Fumonisins B1 + B2 Contents in Maize Kernel
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作者 C. Levasseur O. Surel D. Kleiber 《Journal of Agricultural Science and Technology(B)》 2011年第4期483-494,共12页
The maximal deoxynivalenol (DON) and fumonisins 131 + B2 (FUM) contents in cereals are dictated by the European regulation 1126/2007. The direct measurement of these mycotoxins is a tedious and expensive process.... The maximal deoxynivalenol (DON) and fumonisins 131 + B2 (FUM) contents in cereals are dictated by the European regulation 1126/2007. The direct measurement of these mycotoxins is a tedious and expensive process. Our study is based on an alternative tool: near infrared spectroscopy. Different models were developed on 374 maize samples to predict their DON and FUM contents. Several parameters have been determined and used in a multivariate data analysis. Three models were developed: (1) a classification model based on Discriminant Factor Analysis (DFA), (2) a linear model based on ANalysis of COVAriance (ANCOVA) and (3) a Partial Least Squares Discriminant Analysis model (PLS-DA). Firstly, the performances of the DFA model for assessing DON and FUM risk were similar: 69 and 72% of the validation samples were respectively well classified. In the second part, the performances of the ANCOVA model for DON were higher than for FUM. The r2 was worth respectively 0.85 and 0.69. In the last part, the performances of the PLS-DA models were better for FUM than for DON. These results show that an evaluation of the mycotoxin risk is possible by analyzing selected kernel parameters measurable by secondary analytical such as near-infrared spectroscopy. Further work is needed to improve the models, adding more samples and using non linear approaches. 展开更多
关键词 Maize kernel mycotoxins contents (deoxynivalenol and fumonisins) risk assessment near infrared spectroscopy.
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Network Fault Analysis from Passive Measurement 被引量:1
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作者 Huang Lisheng Wang Wenyong +1 位作者 Li Changchun Lan Yunhai 《China Communications》 SCIE CSCD 2012年第5期64-74,共11页
A new passive method for automatic dis-covery and bcation of network failure is proposed. This method employs a passive measurement to collect infonmtion and events from network traffic, and em-ploys a rrodel-based re... A new passive method for automatic dis-covery and bcation of network failure is proposed. This method employs a passive measurement to collect infonmtion and events from network traffic, and em-ploys a rrodel-based reasoning system to detect and locate network faults. Measurement points are de-ployed in a backbone network to capture the traffic and then evaluate the Quality of Service (QoS) metrics of end-to-end IP conversations. A muting rrodel is al-so established for the observed network to simulate the attributes and activities of reuters and links. This muting model also deduces the muting path for each IP conversation, and thus the QoS metrics of IP con-versations are mapped into the metrics of paths. With the inforrmtion of shared links of overlapping paths and network torrography technique, the QoS metrics of links can also be estimated, and the poorly rated links are picked out as failure points. This method is imple-mented in a tool named FaultMan, which is deployed in a campus network. Test results have shown its availa-bility in rriddle-scale networks. 展开更多
关键词 passive measurement network fault lo-cation model-based reasoning
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Grain Size Analysis and Wave Modeling on the Coastal Fringe of Larache (Ras R'mel Beach), North West of Morocco
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作者 Nadia El Mekadem Brahim EI Moutchoul +1 位作者 Ana M. Bemabeu Khalil El Hajjaji 《Journal of Shipping and Ocean Engineering》 2012年第4期244-248,共5页
The studied area is located in the northwestern Morocco. It occupies a 2.5 km long of coastline on the Atlantic shore. It is oriented NNE-SSW, clearly exposed to the dominant swells coming from west to northwest. The ... The studied area is located in the northwestern Morocco. It occupies a 2.5 km long of coastline on the Atlantic shore. It is oriented NNE-SSW, clearly exposed to the dominant swells coming from west to northwest. The aim of this study is to determine the capacity of the waves that hit the shore to transport the sediments. To achieve our goal we chose a methodology that combines field sampling and laboratory analysis with digital modeling. In the first phase we sampled sediments from the study area along and across the beach line, dry sieving was used to determine the grain size distribution and the statistics derived from the sand samples were used to determine the critical shield stress (z'cr, b) also to investigate the spatial variability and influence of transport on grain size characteristics. As for the second phase, we intended to create a wave climate modeling based on nautical chart, using ArcGIS then Matlab that allowed us to obtain the Swan model for the area. The correlation between those results showed the degree of contribution of wave in the distribution of sediments along the shore. 展开更多
关键词 Grain size sedimentary distribution wave modeling Atlantic coast.
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Regional Climate Change and Uncertainty Analysis based on Four Regional Climate Model Simulations over China 被引量:11
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作者 WU Jia GAO Xue-Jie +1 位作者 XU Yin-Long PAN Jie 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第3期147-152,共6页
Four sets of climate change simulations at grid spacing of 50 km were conducted over East Asia with two regional climate models driven at the lateral bounda- ries by two global models for the period 1981-2050. The loc... Four sets of climate change simulations at grid spacing of 50 km were conducted over East Asia with two regional climate models driven at the lateral bounda- ries by two global models for the period 1981-2050. The locus of the study was on the ensemble projection of cli- mate change in the mid-21st century (2031-50) over China. Validation of each simulation and the ensemble average showed good performances of the models overall, as well as advantages of the ensemble in reproducing present day (1981 2000) December-February (DJF), June-August (JJA), and annual (ANN) mean temperature and precipitation. Significant wanning was projected for the mid-21st century, with larger values of temperature increase found in the northern part of China and in the cold seasons. The ensemble average changes of precipitation in DJF, JJA, and ANN were determined, and the uncertainties of the projected changes analyzed based on the consistencies of the simulations. It was concluded that the largest uncertainties in precipitation projection are in eastern China during the summer season (monsoon pre-cipitation). 展开更多
关键词 climate change regional climate model ENSEMBLE China
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Simulation Analysis for Massive Deployment of Variable Renewables Employing an Optimal Power Generation Mix Model
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作者 Ryoichi Komiyama Saeko Shibata Yasumasa Fujii 《Journal of Energy and Power Engineering》 2013年第8期1604-1615,共12页
This paper develops a high time-resolution optimal power generation mix model in its time resolution of 10 minutes on 365 days by linear programming technique. The model allows us to analyse the massive deployment of ... This paper develops a high time-resolution optimal power generation mix model in its time resolution of 10 minutes on 365 days by linear programming technique. The model allows us to analyse the massive deployment of photovoltaic system and wind power generation in power system explicitly considering those short-term output variation. PV (photovoltaic) and wind output are estimated, employing meteorological database. Simulation results reveal that variable fluctuation derived from a high penetration level of those renewables is controlled by quick load following operation of natural gas combined cycle power plant, pumped-storage hydro power, stationary NAS (sodium and sulfur) battery and the output suppression control of PV and wind. It additionally turns out that the operational configuration of those technologies for the renewable variability differs significantly depending on those renewable output variations in each season and solving the seasonal electricity imbalance as well as the daily imbalance is important if variable renewables are massively deployed. 展开更多
关键词 BATTERIES power generation dispatch power generation planning power system economics power system simulation solar power generation wind power generation.
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Comprehensive Appraisal of Provincial Low Carbon Development:A Case Study of China
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作者 Liu Yong 《Chinese Journal of Population,Resources and Environment》 2012年第1期27-31,共5页
In this research,the Factor Analysis model of measuring provincial low carbon development in China has been constructed.Based on data from 30 provinces,an empirical study was developed to measure comprehensive low car... In this research,the Factor Analysis model of measuring provincial low carbon development in China has been constructed.Based on data from 30 provinces,an empirical study was developed to measure comprehensive low carbon development using the Factor Analysis model(Principal Components method and Normalized Varimax Rotation).The results reveal that the provincial marks of low carbon development are generally low and only nine provinces have high marks(more than 0.80).The results also show significant regional disparity.The provincial marks of the eastern region are higher than both the middle and western provinces of China's Mainland.All of the provinces with high marks(more than 0.90) are located in the eastern region,and those with the lowest marks(0.60) are located in the middle region.Furthermore,regional disparity in low carbon development follows the same pattern as economic development in China.Finally,some suggestions for decision-makers are presented. 展开更多
关键词 low carbon development INDICATORS Factor Analysismodel China
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Predicting Business Insolvency: The Latvian Experience
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作者 Ruta Sneidere Inta Bruna 《Journal of Modern Accounting and Auditing》 2011年第5期487-497,共11页
This paper presents investigations of bankruptcy predicting models which can be useful for external users of a financial statement. Only the methods of financial analysis for insolvency prediction, useful on the basis... This paper presents investigations of bankruptcy predicting models which can be useful for external users of a financial statement. Only the methods of financial analysis for insolvency prediction, useful on the basis of financial statements, were investigated. The paper studied the influence of insolvency on the development of the Latvian Economy, including such relevant points: dynamics of number of insolvency cases in Latvia, data of the payment discipline of debts, tax liabilities of the insolvent companies, dynamics of unemployment support payments. Empirical investigations shows that only Altman's Z'" and Fulmer's H models demonstrate accuracy above 80% in all analyzed business sectors and they are applicable for Latvian companies. The other models are useful to some particular business sector. 展开更多
关键词 INSOLVENCY BANKRUPTCY predicting model financial report
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The Modeling of Weather Conditions and Wind Power in Cities of Western Black Sea Region by Using Linear Regression Method
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作者 Beytullah Erdogan Beytullah Erdo~anl, Adnan Topuzl, Sidika Ece Altini~ik2 and Habip Angac2 +1 位作者 Sidika Ece Altinisik Habip Angac 《Journal of Energy and Power Engineering》 2013年第7期1293-1298,共6页
In this study, weather condition data such as the monthly average temperature, relative moisture, wind speed, pressure and the calculated wind power values of Zonguldak, Sinop, Dtizce, Bartm, Kastamonu, Bolu and Karab... In this study, weather condition data such as the monthly average temperature, relative moisture, wind speed, pressure and the calculated wind power values of Zonguldak, Sinop, Dtizce, Bartm, Kastamonu, Bolu and Karabi^k cities located in western Black Sea region were examined for 10 year period (2001-2011). In the modeling of the weather conditions, linear regression analysis was used and the effect of temperature, relative moisture and pressure on wind speed was researched by non-linear regression method. Besides, in this study, the effect of roughness coefficient in cities of western Black Sea region was also taken into consideration and the wind power potentials in 10 m, 25 m and 50 m altitude were researched in detail with the help of WASP (Wind Atlas Analysis and Application) program. In the light of the values obtained by developed models and weather condition data, it was observed that some cities in the western Black Sea region have wind power potential with their effects on environment and energy. 展开更多
关键词 PRESSURE relative moisture wind speed wind power Turkey.
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RESEARCH ON DEEP COAL SEAM MINING FLOOR STARTA WATER BURSTING INFLUENCED FACTORS BASED ON ANALYTIC HIERACHY PROCESS
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作者 SUN Ming ZHENG Wenxiang DUAN Xiaobo 《International Journal of Technology Management》 2014年第4期135-138,共4页
Deep coal seam mining floor strata water bursting is a complicate nonlinear system, whose factors are coupling and influencing themselves. It built the analytic structure model for deep coal seam mining floor strata w... Deep coal seam mining floor strata water bursting is a complicate nonlinear system, whose factors are coupling and influencing themselves. It built the analytic structure model for deep coal seam mining floor strata water bursting, the judgment matrix was found by the expert scoring method, the contribution weights of the influenced factors were given out by the equation analytic process. The thirteen controlling factors and five main controlling factors were put award by analyzing weights, so the result was basically conform to the field practice. The expert scoring method and analytic process can convert the objective fact to the subjective cognition, so it is a method that can turn the qualitative into the quantitative. This can be relative objectively and precisely to study the question of many factors and grey box. 展开更多
关键词 deep coal seam mining floor strata water bursting expert scoring method equation analytic hierachy process controllingfactors main controlling factors
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Landscape design method for a green community based on green building design theory 被引量:5
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作者 Hong-feng GUO Jian GE +2 位作者 Miao YUE Xiao ZHOU Wu JIN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第9期691-700,共10页
Landscape design for a green community should be favorable for the ambient ecological environment and for enhancement of both the local climate of a residential area and the environmental quality of life. This paper p... Landscape design for a green community should be favorable for the ambient ecological environment and for enhancement of both the local climate of a residential area and the environmental quality of life. This paper presents optimization methods for plant landscape design that take account of results of comparisons of noise reduction effects, heat island temperature decreases and effects on ventilation. These methods are based on different plant configurations and various luminous environments, such as exterior sunshine and shaded areas after the simulation of exterior luminous, acoustic and thermal environments of a residential area using the analytic software ECOTECT, CADNA/A, and PHEONICS. Three different types of residential buildings are simulated including a faculty apartment in the Xixi Campus of Zhejiang University, the Huaqing Villa and the Gangwan Jiayuan faculty apartment of Zhejiang University, China, based on green building design theory. In addition, the methods and process flow of landscape design of green residential areas are also described for the improvement of the exterior physical living environment. 展开更多
关键词 Landscape design Green community Green building Exterior physical environment
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Analysis of a mutualism model with stochastic perturbations 被引量:3
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作者 Mei Li Hongjun Gao +1 位作者 Chenfeng Sun Yuezheng Gong 《International Journal of Biomathematics》 2015年第6期19-36,共18页
This paper is concerned with a mutualism ecological model with stochastic perturba- tions. The local existence and uniqueness of a positive solution are obtained with positive initial value, and the asymptotic behavio... This paper is concerned with a mutualism ecological model with stochastic perturba- tions. The local existence and uniqueness of a positive solution are obtained with positive initial value, and the asymptotic behavior to the problem is studied. Moreover, we show that the solution is stochastically bounded, uniformly continuous and stochastic perma- nence. The sufficient conditions for the system to be extinct are given and the conditionsfor the system to be persistent are also established. At last, some figures are presented to illustrate our main results. 展开更多
关键词 Ito's formula mutualism model persistent in mean EXTINCTION uniformlycontinuous.
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Algorithm Based on Morphological Component Analysis and Scale-Invariant Feature Transform for Image Registration 被引量:1
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作者 王刚 李京娜 +3 位作者 苏庆堂 张小峰 吕高焕 王洪刚 《Journal of Shanghai Jiaotong university(Science)》 EI 2017年第1期99-106,共8页
In this paper, we proposed a registration method by combining the morphological component analysis(MCA) and scale-invariant feature transform(SIFT) algorithm. This method uses the perception dictionaries,and combines ... In this paper, we proposed a registration method by combining the morphological component analysis(MCA) and scale-invariant feature transform(SIFT) algorithm. This method uses the perception dictionaries,and combines the Basis-Pursuit algorithm and the Total-Variation regularization scheme to extract the cartoon part containing basic geometrical information from the original image, and is stable and unsusceptible to noise interference. Then a smaller number of the distinctive key points will be obtained by using the SIFT algorithm based on the cartoon part of the original image. Matching the key points by the constrained Euclidean distance,we will obtain a more correct and robust matching result. The experimental results show that the geometrical transform parameters inferred by the matched key points based on MCA+SIFT registration method are more exact than the ones based on the direct SIFT algorithm. 展开更多
关键词 image registration morphological component analysis (MCA) scale-invariant feature transform (SIFT) key point matching TN 911 A
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Solution for a nonlocal elastic bar in tension 被引量:1
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作者 ZHU XiaoWu DAI HuiHui 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第6期1059-1065,共7页
In this paper we use an alternative method to study analytically and numerically for a nonlocal elastic bar in tension.The equilibrium equation of the model is a Fredholm integral equation of the second kind.With the ... In this paper we use an alternative method to study analytically and numerically for a nonlocal elastic bar in tension.The equilibrium equation of the model is a Fredholm integral equation of the second kind.With the aid of an efficient iterative method,we are able to get the approximate analytical solution.For the purpose of comparisons,numerical solutions are also obtained for two types of nonlocal kernels,which show the validity of the analytical solution.The effects of some related parameters are also investigated. 展开更多
关键词 nonlocal elasticity integral equation iterative method ASYMPTOTICS
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Functional singular component analysis based functional additive models
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作者 ZHANG Tao WANG QiHua 《Science China Mathematics》 SCIE CSCD 2016年第12期2443-2462,共20页
We propose a method which uses functional singular component to establish functional additive models. The proposed methodology reduces the curve regression problem to ordinary(i.e., scalar) additive regression problem... We propose a method which uses functional singular component to establish functional additive models. The proposed methodology reduces the curve regression problem to ordinary(i.e., scalar) additive regression problems of the singular components of the predictor process and response process. Consistency of estimators for the nonparametric function and prediction are proved, respectively. A simulation study is conducted to investigate the finite sample performances of the proposed estimators. 展开更多
关键词 functional data functional additive models functional singular component analysis
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A two-level method for sparse time-frequency representation of multiscale data Dedicated to Professor LI TaTsien on the Occasion of His 80th Birthday
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作者 LIU ChunGuang SHI ZuoQiang HOU Thomas Yizhao 《Science China Mathematics》 SCIE CSCD 2017年第10期1733-1752,共20页
Based on the recently developed data-driven time-frequency analysis(Hou and Shi, 2013), we propose a two-level method to look for the sparse time-frequency decomposition of multiscale data. In the two-level method, we... Based on the recently developed data-driven time-frequency analysis(Hou and Shi, 2013), we propose a two-level method to look for the sparse time-frequency decomposition of multiscale data. In the two-level method, we first run a local algorithm to get a good approximation of the instantaneous frequency. We then pass this instantaneous frequency to the global algorithm to get an accurate global intrinsic mode function(IMF)and instantaneous frequency. The two-level method alleviates the difficulty of the mode mixing to some extent.We also present a method to reduce the end effects. 展开更多
关键词 sparse representation time-frequency analysis matching pursuit two-level method end effects
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