期刊文献+
共找到1,879篇文章
< 1 2 94 >
每页显示 20 50 100
Assessment of active tectonics from geomorphic indices and morphometric parameters in part of Ganga basin 被引量:3
1
作者 Aditya Kumar ANAND Sarada Prasad PRADHAN 《Journal of Mountain Science》 SCIE CSCD 2019年第8期1943-1961,共19页
Ganga river basins exposed to active erosional and deformational processes. The recurrence of landslides, floods, and seismic activities makes it more susceptible to deformational activities. The tectonic analysis usi... Ganga river basins exposed to active erosional and deformational processes. The recurrence of landslides, floods, and seismic activities makes it more susceptible to deformational activities. The tectonic analysis using geomorphic indices and morphometric parameters will help in determining the hazard-prone area of the river basin. Geomorphic indices and morphometric parameters are calculated to investigate the role of neotectonic activities, as it acts as a controlling factor in the development of landforms in the tectonically active terrains. Neotectonic activities influence the terrain topography, which significantly affects the drainage system and geomorphological setup of the area. In this study, the assessment of active tectonics of study area was determined using Advanced Spaceborne Thermal Emission and Reflection Radiometer(ASTER) Global Digital Elevation Model(GDEM) based on Geomorphic Indices(Stream Length Gradient index, Hypsometric integral, Asymmetry factor, Basin shape, Valley floor width to Valley height ratio, Mountain front sinuosity index) cumulatively with Linear, Areal and Relief morphometric parameters on 27 delineated basins of the study area. The combined classification of Relative Tectonic Activity Index(Iat) and morphometric parameters of 27 basins categorized all the zones into four different classes:Class 1 – Very High(<1.97;410 km^2);Class 2 – High(1.97 – 2.05;275 km^2);Class 3 – Moderate(2.05 – 2.21;273 km^2),and Class 4 – Low(>2.21;299 km^2). The basins with tectonic activities have a consistent relationship with structural disturbances, basin geometry, and field studies. The tectonically active zonation of a part of Ganga basin using geomorphic indices and morphometric parameters suggest that it has significant influence of neotectonic activities in a part of Ganga basin. 展开更多
关键词 Linear parameters Areal parameters RELIEF parameters Geomorphic Indices RELATIVE TECTONIC activity Index Ganga river BASINS
下载PDF
Application of Time Scale to Parameters Tuning of Active Disturbance Rejection Controller for Induction Motor 被引量:2
2
作者 邵立伟 廖晓钟 张宇河 《Journal of Beijing Institute of Technology》 EI CAS 2007年第4期419-423,共5页
Active disturbance rejection controller (ADRC) has good performance in induction motor (IM) control system, but controller parameter is difficult to tune. A method of tuning ADRC parameter by time scale is analyzed. T... Active disturbance rejection controller (ADRC) has good performance in induction motor (IM) control system, but controller parameter is difficult to tune. A method of tuning ADRC parameter by time scale is analyzed. The IM time scale is obtained by theoretical analysis. Combining the relations between scale time and ADRC parameters, ADRC parameter tuning in IM vector control based stator flux oriented is obtained. This parameter tuning method is validated by simulations and it provides a new technique for tuning of ADRC parameters of IM. 展开更多
关键词 time scale active disturbance rejection controller parameter tuning
下载PDF
Effect of lateral structure parameters of SiGe HBTs on synthesized active inductors
3
作者 赵彦晓 张万荣 +3 位作者 黄鑫 谢红云 金冬月 付强 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期434-439,共6页
The effect of lateral structure parameters of transistors including emitter width, emitter length, and emitter stripe number on the performance parameters of the active inductor (AI), such as the effective inductanc... The effect of lateral structure parameters of transistors including emitter width, emitter length, and emitter stripe number on the performance parameters of the active inductor (AI), such as the effective inductance Ls, quality factor Q, and self-resonant frequency too is analyzed based on 0.35%tm SiGe BiCMOS process. The simulation results show that for AI operated under fixed current density Jc, the HBT lateral structure parameters have significant effect on Ls but little influence on Q and 090, and the larger Ls can be realized by the narrow, short emitter stripe and few emitter stripes of SiGe HBTs. On the other hand, for AI with fixed HBT size, smaller Jc is beneficial for AI to obtain larger Ls, but with a cost of smaller Q and 090. In addition, under the fixed collector current Ic, the larger the size of HBT is, the larger Ls becomes, but the smaller Q and ab become. The obtained results provide a reference for selecting geometry of transistors and operational condition in the design of active inductors. 展开更多
关键词 SiGe HBT lateral structure parameters active inductor
下载PDF
Influence of Active Charcoal and Plant Position on Some Morphological Parameters of a Local Variety of Okra (<i>Abelmoschus caillei</i>)
4
作者 Kouame N’Guessan Koffi Ahébé Marie Hélène +2 位作者 Kouassi N’Dri Jacob N’Guessan N’Guessan Alain Yatty Kouadio Justin 《American Journal of Plant Sciences》 2017年第9期2021-2030,共10页
Okra is a plant rich in nutrients and is very well consumed in C&ocirc;te d’Ivoire. Despite its many benefits, the production of this vegetable is still weak in our country. The reasons for this include the inade... Okra is a plant rich in nutrients and is very well consumed in C&ocirc;te d’Ivoire. Despite its many benefits, the production of this vegetable is still weak in our country. The reasons for this include the inadequate selection of varieties, the high cost of inputs and the poverty of the soil for its cultivation. One of the alternatives for sustained production is to solve the problem of soil fertility. In the case of our work, the aim is to improve the yield of okra. To achieve this goal, experiments were undertaken to evaluate the impact of activated charcoal on morphological parameters of a local okra variety. For this purpose, the charcoal used was activated in three different times (activation time equal to 0 days, 15 days and 30 days). The experimental device used is a split-plot with three repetitions, each comprising 12 elementary plots. The various charcoals were buried the same day. Then, the seedling was done with two positions including outside position and inside position. Observations were made on 360 plants. An analysis of the variances was carried out on the morphological parameters. Fruit mass is the variable most influenced by activated charcoal. Thus, the greatest value of the mass was obtained with the charcoal CA0, with outside position. 展开更多
关键词 activATED Charcoal OKRA POSITION MORPHOLOGICAL parameters
下载PDF
Multiple Emulsions Able to Be Used for Oral Administration of Active Pharmaceutical Ingredients: Physico-Chemical Parameters Study of Different Phases
5
作者 Louis Augustin Diaga Diouf Alphonse Rodrigue Djiboune +4 位作者 Mamadou Soumboundou Sidy Mouhamed Dieng Papa Mady Sy Gora Mbaye Mounibé Diarra 《Journal of Modern Physics》 2020年第10期1528-1535,共8页
Multiple emulsions are of great therapeutic interest especially in the administration of medicines which can be inactivated by digestive enzymes;moreover the researches of formulation not being often easy, a control o... Multiple emulsions are of great therapeutic interest especially in the administration of medicines which can be inactivated by digestive enzymes;moreover the researches of formulation not being often easy, a control of the different phases physicochemical parameters would be of great interest in rapid formulations and at low cost. When formulating emulsions, the preliminary tests, also known as formulation tests, constitute a step which can be long and expensive because of the quantity of reagents that can be used. A rigorous methodology could thus be of great interest, which is at the aim of our study which consists of evaluating the physico-chemical parameters of different phases used to make thus multiple emulsions. In our study, physico-chemical parameters such as conductivity, pH, density, viscosity, and surface tension have been studied by direct measurement using equipment and also by means of suitable mounting. The results showed that the pH and the surface tension have an important role in the prediction of the stability of emulsions, these latter must be of the same order of magnitude. For all phases conductivity does not have too much interest apart from helping to determine the type of the emulsion. 展开更多
关键词 active Pharmaceutical Ingredients Multiple Emulsions STABILITY Physico-Chemical parameters
下载PDF
Additivity of pore structural parameters of granular activated carbons derived from different coals and their blends 被引量:7
6
作者 Yao Xin Xie Qiang +3 位作者 Yang Chuan Zhang Bo Wan Chaoran Cui Shanshan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期661-667,共7页
A series of granular activated carbons (GACs) were prepared by briquetting method from Chinese coals of different ranks and their blends, with coal pitch as the binder. Pore structural parameters including BET speci... A series of granular activated carbons (GACs) were prepared by briquetting method from Chinese coals of different ranks and their blends, with coal pitch as the binder. Pore structural parameters including BET specific surface area (SBEr), total pore volume (Vr) and average pore diameter (da) were measured and cal- culated as well as process parameters such as yield of char (CY) and burn-off (B). The relationship between the pore structural parameters of the GAC from coal blend (BC-GAC) and the ones of the GACs from corresponding single coals (SC-GACs) was analyzed, in which an index, the relative error (δ), was presented to define the bias between fitted values and experimental values of these parameters of the BC-GACs. The results show that the BC-GAC keeps qualitatively the pore structural features of the SC-GACs; as concerned as the quantitative relationship, the pore structural parameters of the BC-GAC from coal blend consisting of non-caking coals can be obtained by adding proportionally the pore structural parameters of the SC-GACs with a less than 10%. Meanwhile, for the BC-GAC from coal blend containing weak caking bituminous coal, the δ increases up to 25% and the experimental pore size distribution differs greatly from the fitted one. 展开更多
关键词 Granular activated carbon Coal blend Pore structural parameters Additivity
下载PDF
Adaptive linear active disturbance-rejection control strategy reduces the impulse current of compressed air energy storage connected to the grid
7
作者 Jianhui Meng Yaxin Sun Zili Zhang 《Global Energy Interconnection》 EI CSCD 2024年第5期577-589,共13页
The merits of compressed air energy storage(CAES)include large power generation capacity,long service life,and environmental safety.When a CAES plant is switched to the grid-connected mode and participates in grid reg... The merits of compressed air energy storage(CAES)include large power generation capacity,long service life,and environmental safety.When a CAES plant is switched to the grid-connected mode and participates in grid regulation,using the traditional control mode with low accuracy can result in excess grid-connected impulse current and junction voltage.This occurs because the CAES output voltage does not match the frequency,amplitude,and phase of the power grid voltage.Therefore,an adaptive linear active disturbance-rejection control(A-LADRC)strategy was proposed.Based on the LADRC strategy,which is more accurate than the traditional proportional integral controller,the proposed controller is enhanced to allow adaptive adjustment of bandwidth parameters,resulting in improved accuracy and response speed.The problem of large impulse current when CAES is switched to the grid-connected mode is addressed,and the frequency fluctuation is reduced.Finally,the effectiveness of the proposed strategy in reducing the impact of CAES on the grid connection was verified using a hardware-in-the-loop simulation platform.The influence of the k value in the adaptive-adjustment formula on the A-LADRC was analyzed through simulation.The anti-interference performance of the control was verified by increasing and decreasing the load during the presynchronization process. 展开更多
关键词 Compressed air energy storage Linear active disturbance-rejection control Smooth grid connection Impulse current Adaptive adjustment of bandwidth parameters
下载PDF
Reinforcement learning based parameter optimization of active disturbance rejection control for autonomous underwater vehicle 被引量:2
8
作者 SONG Wanping CHEN Zengqiang +1 位作者 SUN Mingwei SUN Qinglin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第1期170-179,共10页
This paper proposes a liner active disturbance rejection control(LADRC) method based on the Q-Learning algorithm of reinforcement learning(RL) to control the six-degree-of-freedom motion of an autonomous underwater ve... This paper proposes a liner active disturbance rejection control(LADRC) method based on the Q-Learning algorithm of reinforcement learning(RL) to control the six-degree-of-freedom motion of an autonomous underwater vehicle(AUV).The number of controllers is increased to realize AUV motion decoupling.At the same time, in order to avoid the oversize of the algorithm, combined with the controlled content, a simplified Q-learning algorithm is constructed to realize the parameter adaptation of the LADRC controller.Finally, through the simulation experiment of the controller with fixed parameters and the controller based on the Q-learning algorithm, the rationality of the simplified algorithm, the effectiveness of parameter adaptation, and the unique advantages of the LADRC controller are verified. 展开更多
关键词 autonomous underwater vehicle(AUV) reinforcement learning(RL) Q-LEARNING linear active disturbance rejection control(LADRC) motion decoupling parameter optimization
下载PDF
Proportion integral-type active disturbance rejection generalized predictive control for distillation process based on grey wolf optimization parameter tuning 被引量:1
9
作者 Jia Ren Zengqiang Chen +2 位作者 Mingwei Sun Qinglin Sun Zenghui Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第9期234-244,共11页
The high-purity distillation column system is strongly nonlinear and coupled,which makes it difficult to control.Active disturbance rejection control(ADRC)has been widely used in distillation systems,but it has limita... The high-purity distillation column system is strongly nonlinear and coupled,which makes it difficult to control.Active disturbance rejection control(ADRC)has been widely used in distillation systems,but it has limitations in controlling distillation systems with large time delays since ADRC employs ESO and feedback control law to estimate the total disturbance of the system without considering the large time delays.This paper designs a proportion integral-type active disturbance rejection generalized predictive control(PI-ADRGPC)algorithm to control the distillation column system with large time delay.It replaces the PD controller in ADRC with a proportion integral-type generalized predictive control(PI-GPC),thereby improving the performance of control systems with large time delays.Since the proposed controller has many parameters and is difficult to tune,this paper proposes to use the grey wolf optimization(GWO)to tune these parameters,whose structure can also be used by other intelligent optimization algorithms.The performance of GWO tuned PI-ADRGPC is compared with the control performance of GWO tuned ADRC method,multi-verse optimizer(MVO)tuned PI-ADRGPC and MVO tuned ADRC.The simulation results show that the proposed strategy can track reference well and has a good disturbance rejection performance. 展开更多
关键词 Proportion integral-type active disturbance rejection generalized predictive control Grey wolf optimization parameter tuning DISTILLATION Process control PREDICTION
下载PDF
Identification of expected seismic activity areas by forecasting complex seismic-mode parameters in Uzbekistan
10
作者 T.U.Artikov R.S.Ibragimov +1 位作者 T.L.Ibragimova M.A.Mirzaev 《Geodesy and Geodynamics》 2018年第2期121-130,共10页
In this paper, the author proposed a methodology to reveal expected seismic activation places for coming years by a complex of forecasting parameters of a seismic mode. Areas in Uzbekistan where currently observed ano... In this paper, the author proposed a methodology to reveal expected seismic activation places for coming years by a complex of forecasting parameters of a seismic mode. Areas in Uzbekistan where currently observed anomalies in various parameters of a seismic mode has been revealed. By number of displayed abnormal signs the areas has been ranked based on probability of occurrence of strong earthquakes there. It has prepared schemes of the synoptic forecast of expected seismic activation places in case of occurrence of strong earthquakes in the Central-Asian region. 展开更多
关键词 Long-term forecast of earthquakes parameters of seismic mode Seismic activity Seismic gap
下载PDF
Dynamical modelling of cardiac electrical activity using bidomain approach: The effects of variation of ionic model parameters
11
作者 Adebisi O. Ibrahim Adejumobi I. Adediji Dada J. Olufemi 《Journal of Biomedical Science and Engineering》 2013年第6期598-608,共11页
This work presents the dynamical modelling of cardiac electrical activity using bidomain approach. It focuses on the effects of variation of the ionic model parameters on cardiac wave propagation. Cardiac electrical a... This work presents the dynamical modelling of cardiac electrical activity using bidomain approach. It focuses on the effects of variation of the ionic model parameters on cardiac wave propagation. Cardiac electrical activity is governed by partial differential equations coupled to a system of ordinary differential equations. Numerical simulation of these equations is computationally expensive due to their non-linearity and stiffness. Nevertheless, we adopted the bidomain model due to its ability to reflect the actual cardiac wave propagation. The derived bidomain equations coupled with FitzHugh-Nagumo’s ionic equations were time-discretized using explicit forward Euler method and space-discretized using 2-D network modelling to obtain linearized equations for transmembrane potential Vm, extracellular potential φe and gating variable w. We implemented the discretized model and performed simulation experiments to study the effects of variation of ionic model parameters on the propagation of electrical wave across the cardiac tissue. Time characteristic of transmembrane potential, Vm, in the normal cardiac tissue was obtained by setting the values of ionic model parameters to 0.2, 0.2, 0.7 and 0.8 for excitation rate constant ε1, recovery rate constant ε2, recovery decay constant γ and excitation decay constant β respectively. Changing the values of ε1, ε2 to 0.04 and 0.28 respectively, the obtained Vm showed a time dilation at 0.04 indicating cardiac arrhythmia but no significant change to Vm was observed at 0.28. Also, changing β to 0.3 and 1.1 and γ to 0.4 and 1.2 sequentially, there was no significant change to the time characteristic of Vm. The obtained results revealed that only decrease in ε1, ε2 impacted significantly on the cardiac wave propagation. 展开更多
关键词 Dynamical Modelling CARDIAC Electrical activity BIDOMAIN MODEL Ionic MODEL parameters DISCRETIZATION TRANSMEMBRANE Potential
下载PDF
Finite-time Mittag-Leffler synchronization of fractional-order delayed memristive neural networks with parameters uncertainty and discontinuous activation functions
12
作者 Chong Chen Zhixia Ding +1 位作者 Sai Li Liheng Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期127-138,共12页
The finite-time Mittag-Leffler synchronization is investigated for fractional-order delayed memristive neural networks(FDMNN)with parameters uncertainty and discontinuous activation functions.The relevant results are ... The finite-time Mittag-Leffler synchronization is investigated for fractional-order delayed memristive neural networks(FDMNN)with parameters uncertainty and discontinuous activation functions.The relevant results are obtained under the framework of Filippov for such systems.Firstly,the novel feedback controller,which includes the discontinuous functions and time delays,is proposed to investigate such systems.Secondly,the conditions on finite-time Mittag-Leffler synchronization of FDMNN are established according to the properties of fractional-order calculus and inequality analysis technique.At the same time,the upper bound of the settling time for Mittag-Leffler synchronization is accurately estimated.In addition,by selecting the appropriate parameters of the designed controller and utilizing the comparison theorem for fractional-order systems,the global asymptotic synchronization is achieved as a corollary.Finally,a numerical example is given to indicate the correctness of the obtained conclusions. 展开更多
关键词 FRACTIONAL-ORDER DELAYED memristive neural networks(FDMNN) parameters uncertainty DISCONTINUOUS activATION functions FINITE-TIME Mittag-Leffler SYNCHRONIZATION
下载PDF
Research on main circuit parameter coupling relationship of single-phase shunt active power filter
13
作者 ZHANG Zi-qi TIAN Ming-xing +1 位作者 SUN Li-jun GAO Yun-bo 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第2期143-151,共9页
There is a certain coupling relationship among the main circuit parameters of a single-phase shunt active power filter(SAPF),which has a great influence on the reasonable selection of various parameter values.By analy... There is a certain coupling relationship among the main circuit parameters of a single-phase shunt active power filter(SAPF),which has a great influence on the reasonable selection of various parameter values.By analyzing the calculation methods of the inductance of alternating current(AC)side and the voltage and capacitance values of direct current(DC)side in the existing single/three-phase SAPF main circuit,a specific single-phase SAPF circuit parameter analytical expression was obtained.Aiming at the coupling relationship among the variables in the resulting expression,the model was optimized and analyzed in MATLAB,and a complete set of parameters design scheme was obtained,which ensure the comprehensive optimization target of the post-harmonic content below 2% is compensated under a specific load.The simulation and experimental procedures verify the correctness of the selected parameters. 展开更多
关键词 shut active power filter(SAPF) coupling relationship parameter design scheme
下载PDF
The K Method for Estimating Earthquake Activity Parameters and Effect of the Boundary Uncertainty of the Source Region:Discussion on the Seismic Zoning Method
14
作者 Huang Yurui and Zhang TianzhongInstitute of Geophysics,SSB,Beijing 100081,China 《Earthquake Research in China》 1997年第3期75-81,共7页
Two aspects of a new method,which can be used for seismic zoning,are introduced in this paper.On the one hand,the approach to estimate b value and annual activity rate proposed by Kijko and Sellevoll needs to use the ... Two aspects of a new method,which can be used for seismic zoning,are introduced in this paper.On the one hand,the approach to estimate b value and annual activity rate proposed by Kijko and Sellevoll needs to use the earthquake catalogue.The existing earthquake catalogue contains both historical and recent instrumental data sets and it is inadequate to use only one part.Combining the large number of historical events with recent complete records and taking the magnitude uncertainty into account,Kijko’s method gives the maximum likelihood estimation of b value and annual activity rate,which might be more realistic.On the other hand,this method considers the source zone boundary uncertainty in seismic hazard analysis,which means the earthquake activity rate across a boundary of a source zone changes smoothly instead of abruptly and avoids too large a gradient in the calculated results. 展开更多
关键词 The K Method for Estimating Earthquake activity parameters and Effect of the Boundary Uncertainty of the Source Region Source activity
下载PDF
Robust Active Suspension Design Subject to Vehicle Inertial Parameter Variations
15
作者 Hai-Ping Du Nong Zhang 《International Journal of Automation and computing》 EI 2010年第4期419-427,共9页
This paper presents an approach in designing a robust controller for vehicle suspensions considering changes in vehicle inertial properties. A four-degree-of-freedom half-car model with active suspension is studied in... This paper presents an approach in designing a robust controller for vehicle suspensions considering changes in vehicle inertial properties. A four-degree-of-freedom half-car model with active suspension is studied in this paper, and three main performance requirements are considered. Among these requirements, the ride comfort performance is optimized by minimizing the Ho~ norm of the transfer function from the road disturbance to the sprung mass acceleration, while the road holding performance and the suspension deflection limitation are guaranteed by constraining the generalized H2 (GH2) norms of the transfer functions from the road disturbance to the dynamic tyre load and the suspension deflection to be less than their hard limits, respectively. At the same time, the controller saturation problem is considered by constraining its peak response output to be less than a given limit using the GH2 norm as well. By solving the finite number of linear matrix inequalities (LMIs) with the minimization optimization procedure, the controller gains, which are dependent on the time-varying inertial parameters, can be obtained. Numerical simulations on both frequency and bump responses show that the designed parameter-dependent controller can achieve better active suspension performance compared with the passive suspension in spite of the variations of inertial parameters. 展开更多
关键词 active suspension half-car suspension model parameter-dependent control linear matrix inequalities (LMIs)
下载PDF
New formulae for calculating activities from binary system phase diagrams containing solid solution by introducing the parameterθ 被引量:3
16
作者 ZHANG Fan XIE Fanyou +1 位作者 CAI Wenjuan CHOU Kuochih (Applied Science School, University of Science and Technology Beijing, Beijing 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1997年第3期1-4,共4页
New formulae for calculating activities and activity coefficients from binary phase diagrams containing solidsolution are presented. In the new formulae, a parameterθ is introduced. It seems be more efficient The app... New formulae for calculating activities and activity coefficients from binary phase diagrams containing solidsolution are presented. In the new formulae, a parameterθ is introduced. It seems be more efficient The application ofthese formulae to system Ag-Pb proves its efficiency. 展开更多
关键词 phase diagram activITY activity coefficient solution θ parameter
下载PDF
AN ASSESSMENT OF INTERACTION PARAMETERS IN BINARY METALLIC SYSTEMS 被引量:2
17
作者 Z. T. Ma and D. Janke(Institute of Iron and Steel Technology, Freiberg University of Mining and Technology, Germany) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第2期127-136,共10页
An approach of describing the thermodynamics of binary alloys is developed which is based on an exact expression of infinite MacLaurin series of molar excess Gibbs free energy. This new approach is successfully used t... An approach of describing the thermodynamics of binary alloys is developed which is based on an exact expression of infinite MacLaurin series of molar excess Gibbs free energy. This new approach is successfully used to represent the thermodynamics of binary alloys at higher concentrations. The present results reveal that it is an improper way to evaluate first and second-order interaction parameters simultaneously from the experimental data in the range of higher concentrations due to an inadequate accuracy Of high temperature experiments. 展开更多
关键词 THERMODYNAMICS interaction parameter activITY metallic solution
下载PDF
Regularized inversion for coseismic slip distribution with active constraint balancing 被引量:2
18
作者 TONG Xiao-zhong XIE Wei GAO Da-wei 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第12期2961-2968,共8页
Estimating the spatial distribution of coseismic slip is an ill-posed inverse problem, and solutions may be extremely oscillatory due to measurement errors without any constraints on the coseismic slip distribution. I... Estimating the spatial distribution of coseismic slip is an ill-posed inverse problem, and solutions may be extremely oscillatory due to measurement errors without any constraints on the coseismic slip distribution. In order to obtain stable solution for coseismic slip inversion, regularization method with smoothness-constrained was imposed. Trade-off parameter in regularized inversion, which balances the minimization of the data misfit and model roughness, should be a critical procedure to achieve both resolution and stability. Then, the active constraint balancing approach is adopted, in which the trade-off parameter is regarded as a spatial variable at each model parameter and automatically determined via the model resolution matrix and the spread function. Numerical experiments for a synthetical model indicate that regularized inversion using active constraint balancing approach can provides stable inversion results and have low sensitivity to the knowledge of the exact character of the Gaussian noise. Regularized inversion combined with active constraint balancing approach is conducted on the 2005 Nias earthquake. The released moment based on the estimated coseismic slip distribution is 9.91×1021 N·m, which is equivalent to a moment magnitude of 8.6 and almost identical to the value determined by USGS. The inversion results for synthetic coseismic uniform-slip model and the 2005 earthquake show that smoothness-constrained regularized inversion method combined with active constraint balancing approach is effective, and can be reasonable to reconstruct coseismic slip distribution on fault. 展开更多
关键词 COSEISMIC SLIP INVERSION trade-off parameter active CONSTRAINT balancing model resolution matrix spread function
下载PDF
Thermodynamic properties and mixing thermodynamic parameters of binary homogeneous metallic melts 被引量:2
19
作者 ZHANG ManMetallurgical Engineering School, University of Science and Technology Beijing, Beijing 100083, China 《Rare Metals》 SCIE EI CAS CSCD 2003年第1期25-32,共8页
After the investigation on the thermodynamic properties and mixingthermodynamic parameters of binary homogeneous metallic melts involving compound, peritectic as wellas solid solution, it was found that the equations ... After the investigation on the thermodynamic properties and mixingthermodynamic parameters of binary homogeneous metallic melts involving compound, peritectic as wellas solid solution, it was found that the equations of mixing free energy DELTA G^m and excess freeenergy DELTA G^(XS) of them can he expressed by the following equations: DELTA G^m = SIGMA x [SIGMAN_i DELTA G_I^(THETA) + RT(SIGMA N_j ln N_j + SIGMA N_i ln N_i )] and DELTA G^(XS) = DELTA G^m -RT(a ln a + b ln b), respectively. 展开更多
关键词 metallic melt mixing thermodynamic parameter coexistence theory activity mass action concentration
下载PDF
Thermodynamic properties and mixing thermodynamic parameters of two-phase metallic melts 被引量:3
20
作者 JianZhang 《Journal of University of Science and Technology Beijing》 CSCD 2005年第3期213-220,共8页
Based on the calculating model of metallic melts involving eutectic, the calculating equations of mixing thermodynamic parameters for two phase metallic melts have been formulated in the light of those equations of ho... Based on the calculating model of metallic melts involving eutectic, the calculating equations of mixing thermodynamic parameters for two phase metallic melts have been formulated in the light of those equations of homogeneous solutions. Irrespective as to whether the activity deviation relative to Raoultian behavior is positive or negative, or the deviation is symmetrical or unsym-metrical, the evaluated results not only agree well with experimental values, but also strictly obey the mass action law. This testifies that these equations can authentically reflect the structural reality and mixing thermodynamic characteristics of two-phase metallic melts. The calculating equations of mixing thermodynamic parameters for the model of two phase metallic melts offer two practical criteria (activity and mixing thermodynamic parameters) and one theoretical criterion (the mass action law). 展开更多
关键词 mass action law mixing thermodynamic parameters EUTECTIC activity mass action concentration
下载PDF
上一页 1 2 94 下一页 到第
使用帮助 返回顶部