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State of health prediction for lithium-ion batteries based on ensemble Gaussian process regression
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作者 HUI Zhouli WANG Ruijie +1 位作者 FENG Nana YANG Ming 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期397-407,共11页
The performance of lithium-ion batteries(LIBs)gradually declines over time,making it critical to predict the battery’s state of health(SOH)in real-time.This paper presents a model that incorporates health indicators ... The performance of lithium-ion batteries(LIBs)gradually declines over time,making it critical to predict the battery’s state of health(SOH)in real-time.This paper presents a model that incorporates health indicators and ensemble Gaussian process regression(EGPR)to predict the SOH of LIBs.Firstly,the degradation process of an LIB is analyzed through indirect health indicators(HIs)derived from voltage and temperature during discharge.Next,the parameters in the EGPR model are optimized using the gannet optimization algorithm(GOA),and the EGPR is employed to estimate the SOH of LIBs.Finally,the proposed model is tested under various experimental scenarios and compared with other machine learning models.The effectiveness of EGPR model is demonstrated using the National Aeronautics and Space Administration(NASA)LIB.The root mean square error(RMSE)is maintained within 0.20%,and the mean absolute error(MAE)is below 0.16%,illustrating the proposed approach’s excellent predictive accuracy and wide applicability. 展开更多
关键词 lithium-ion batteryies(LIBs) ensemble Gaussian process regression(EGPR) state of health(SOH) health indicators(HIs) gannet optimization algorithm(GOA)
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Analysis and Optimization of the Electrohydraulic Forming Process of Sinusoidal Corrugation Tubes
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作者 Da Cai Yinlong Song +2 位作者 Hao Jiang Guangyao Li Junjia Cui 《Fluid Dynamics & Materials Processing》 EI 2024年第4期873-887,共15页
Aluminum alloy thin-walled structures are widely used in the automotive industry due to their advantages related to light weight and crashworthiness.They can be produced at room temperature by the electrohydraulic for... Aluminum alloy thin-walled structures are widely used in the automotive industry due to their advantages related to light weight and crashworthiness.They can be produced at room temperature by the electrohydraulic forming process.In the present study,the influence of the related parameters on the forming quality of a 6063 aluminum alloy sinusoidal corrugation tube has been assessed.In particular,the orthogonal experimental design(OED)and central composite design(CCD)methods have been used.Through the range analysis and variance analysis of the experimental data,the influence degree of wire diameter(WD)and discharge energy(DE)on the forming quality was determined.Multiple regression analysis was performed using the response surface methodology.A prediction model for the attaching-die state coefficient was established accordingly.The following optimal arrangement of parameters was obtained(WD=0.759 mm,DE=2.926 kJ).The attaching-die state coefficient reached the peak value of 0.001.Better optimized wire diameter and discharge energy for a better attaching-die state could be screened by CCD compared with OED.The response surface method in CCD was more suitable for the design and optimization of the considered process parameters. 展开更多
关键词 Electrohydraulic forming aluminum alloy tube process parameters attaching-die state 1 Introduction
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Effects of Solid-State Reaction Synthesis Processing Parameters on Thermoelectric Properties of Mg_2Si 被引量:2
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作者 姜洪义 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第2期55-56,共2页
The Mg_(2)Si-matrix thermoelectric material was synthesized by low temperature solid-state reaction.This paper studies the effects of holding time and reaction temperature on the particle size and the properties of th... The Mg_(2)Si-matrix thermoelectric material was synthesized by low temperature solid-state reaction.This paper studies the effects of holding time and reaction temperature on the particle size and the properties of the material,and also studies effects of doping elemental Sb,Te and their doping seqence on the properties of the material.The result shows that excessively high temperature and elongated holding time of solid-state reaction are harmful,there is a range of particle size to ensure optimum properties and the doping sequence of Sb or Te without influencing the properties. 展开更多
关键词 solid-state reaction processing parameters Mg_2Si based compounds
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DIGITAL PROCESSING OF THE POLARIZATION STATE OF GEOPHYSICAL ULF SIGNALS
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作者 赵正予 《Journal of Electronics(China)》 1994年第3期262-267,共6页
In this paper, the evaluation by running window smoothing is used for the digital processing of the polarization of geophysical ULF signals. The observed signals are resolved into two orthogonal complex components so ... In this paper, the evaluation by running window smoothing is used for the digital processing of the polarization of geophysical ULF signals. The observed signals are resolved into two orthogonal complex components so that it is no longer necessary to consider the phase and amplitude of the signals simultaneously. 展开更多
关键词 ULF signal POLARIZATION state DIGITAL processing
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Northwestern Polytechnical University State Key Laboratory of Solidification Processing
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《China Foundry》 SCIE CAS 2005年第1期75-75,共1页
关键词 Northwestern Polytechnical University state Key Laboratory of Solidification processing
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Local Hybrid Linear State Estimation for Electric Power Systems Using Stream Processing
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作者 Kang Sun Manyun Huang +2 位作者 Zhinong Wei Yuzhang Lin Guoqiang Sun 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2024年第3期1259-1268,共10页
The increasing penetration of renewable energy resources with highly fluctuating outputs has placed increasing concern on the accuracy and timeliness of electric power system state estimation(SE).Meanwhile,we note tha... The increasing penetration of renewable energy resources with highly fluctuating outputs has placed increasing concern on the accuracy and timeliness of electric power system state estimation(SE).Meanwhile,we note that only a fraction of system states fluctuate at the millisecond level and require to be updated.As such,refreshing only those states with significant variation would enhance the computational efficiency of SE and make fast-continuous update of states possible.However,this is difficult to achieve with conventional SE methods,which generally refresh states of the entire system every 4–5 s.In this context,we propose a local hybrid linear SE framework using stream processing,in which synchronized measurements received from phasor measurement units(PMUs),and trigger/timingmode measurements received from remote terminal units(RTUs)are used to update the associated local states.Moreover,the measurement update process efficiency and timeliness are enhanced by proposing a trigger measurement-based fast dynamic partitioning algorithm for determining the areas of the system with states requiring recalculation.In particular,non-iterative hybrid linear formulations with both RTUs and PMUs are employed to solve the local SE problem.The timeliness,accuracy,and computational efficiency of the proposed method are demonstrated by extensive simulations based on IEEE 118-,300-,and 2383-bus systems. 展开更多
关键词 Fast dynamic partitioning local hybrid linear state estimation phasor measurement units stream processing TIMELINESS trigger/timing-mode measurements
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Local Partial Least Squares Based Online Soft Sensing Method for Multi-output Processes with Adaptive Process States Division 被引量:3
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作者 邵伟明 田学民 王平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期828-836,共9页
Local learning based soft sensing methods succeed in coping with time-varying characteristics of processes as well as nonlinearities in industrial plants. In this paper, a local partial least squares based soft sensin... Local learning based soft sensing methods succeed in coping with time-varying characteristics of processes as well as nonlinearities in industrial plants. In this paper, a local partial least squares based soft sensing method for multi-output processes is proposed to accomplish process states division and local model adaptation,which are two key steps in development of local learning based soft sensors. An adaptive way of partitioning process states without redundancy is proposed based on F-test, where unique local time regions are extracted.Subsequently, a novel anti-over-fitting criterion is proposed for online local model adaptation which simultaneously considers the relationship between process variables and the information in labeled and unlabeled samples. Case study is carried out on two chemical processes and simulation results illustrate the superiorities of the proposed method from several aspects. 展开更多
关键词 Local learning Online soft sensing Partial least squares F-TEST Multi-output process process state division
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Analytical and numerical investigations of displaced thermal state evolutions in a laser process 被引量:2
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作者 杜传勋 孟祥国 +1 位作者 张冉 王继锁 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期102-108,共7页
We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly ... We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly classical thermal field only related to the laser parameters κ and g. The normal ordering product of density operator of the DTS in the laser channel leads to obtaining the analytical time-evolution expressions of the photon number, Wigner function, and von Neumann entropy. Also, some interesting results are presented via numerically investigating these explicit time-dependent expressions. 展开更多
关键词 displaced thermal state laser process infinitive operator-sum representation photon number Wigner function von Neumann entropy
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Modeling of microstructure evolution of AZ80 magnesium alloy during hot working process using a unified internal state variable method 被引量:5
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作者 Zexing Su Chaoyang Sun +2 位作者 Mingjia Wang Lingyun Qian Xintong Li 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第1期299-313,共15页
In this paper, a unified internal state variable(ISV) model for predicting microstructure evolution during hot working process of AZ80 magnesium alloy was developed. A novel aspect of the proposed model is that the in... In this paper, a unified internal state variable(ISV) model for predicting microstructure evolution during hot working process of AZ80 magnesium alloy was developed. A novel aspect of the proposed model is that the interactive effects of material hardening, recovery and dynamic recrystallization(DRX) on the characteristic deformation behavior were considered by incorporating the evolution laws of viscoplastic flow, dislocation activities, DRX nucleation and boundary migration in a coupled manner. The model parameters were calibrated based on the experimental data analysis and genetic algorithm(GA) based objective optimization. The predicted flow stress, DRX fraction and average grain size match well with experimental results. The proposed model was embedded in the finite element(FE) software DEFORM-3 D via user defined subroutine to simulate the hot compression and equal channel angular extrusion(ECAE) processes. The heterogeneous microstructure distributions at different deformation zones and the dislocation density evolution with competitive deformation mechanisms were captured.This study can provide a theoretical solution for the hot working problems of magnesium alloy. 展开更多
关键词 AZ80 magnesium alloy Internal state variable model Microstructure evolution Dynamic recrystallization Hot working process Finite element simulation
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STATE TRANSFORMATION PROCESSES FOR FREE-FLOATING THREE-LINK PLANAR ROBOTS 被引量:1
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作者 XuMingtao XuYangsheng JamesK.Mills 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第2期166-169,共4页
The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF trans... The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF transformation processes as an alternative to them-DOF transformation process. Two static state transformation processes are studied in detail.First, a single-DOF transformation process is established using a newly defined concept, referred toas transformation planning, and the definite integral of conservation of angular momentum. Second,the governing equation of the single-DOF transformation process is established using the dynamicequations of motion of the robot. This allows the joint torques to be computed to effect the statetransformation. Finally, an extension of the single-DOF transformation process is proposed to extendthe application of this proposed transformation methodology to create a transformation net whichallows the reconfiguration of a robot from one state to many other possible states. 展开更多
关键词 Planar robot Static state Single-DOF transformation process n-elementtransformation net
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Development of process energy intensity formula under different state variables 被引量:3
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作者 陈光 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第6期694-696,共3页
In a production process, the actual energy consumption is greatly affected by the production state. Certain processing operations are classified into six states, including normal production, abnormal production, plann... In a production process, the actual energy consumption is greatly affected by the production state. Certain processing operations are classified into six states, including normal production, abnormal production, planned overhaul, unplanned overhaul, transitional period from unplanned overhaul to normal production (referred for short as unplanned transition) and transitional period from planned overhaul to normal production (referred for short as planned transition). The article takes the analysis of relationship between different states of a certain processing operation and corresponding energy consumptions as a startup point to develop a process energy intensity formula with variables of operating rate, yielding rate and operating frequency, etc. This process energy intensity formula can be used to analyze effectively the pattern of impact exerted by different state variables on energy consumption. 展开更多
关键词 process energy intensity production state production variable operating rate yielding rate
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On Kendall's Conjecture for an Extended Birth-death Q-processes with Instantaneous State and Catastrophes 被引量:3
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作者 WUQun-ying 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第1期41-46,共6页
A new structure with the special property that instantaneous state and catas-trophes is imposed to ordinary birth-death processes is considered. Kendall's conjecture forthe processes is proved to be right.
关键词 extended birth-death process instantaneous state Kendall's conjecture
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The Processing Mineralogy for Lead and Zinc Oxide Ore in Sichuan 被引量:1
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作者 YANG Mei XIAO Wending +2 位作者 YANG Xiang LIANG Dongyun WU Yan 《矿物学报》 CAS CSCD 北大核心 2013年第S1期125-125,共1页
Using variety of modern testing methods, the processing mineralogical characteristics for a lead and zinc oxide ore in Sichuan were studied systematically. The chemical analysis result shows that the lead and zinc oxi... Using variety of modern testing methods, the processing mineralogical characteristics for a lead and zinc oxide ore in Sichuan were studied systematically. The chemical analysis result shows that the lead and zinc oxide content exceeding the minimum industrial grade and iron ore, total iron content reaches a minimum industrial grade and associated with gold and silver; The mineralogical analysis result shows that lead and zinc mineral composition and configuration are very complexity. The zinc minerals and zinciferous minerals are sphalerite, hemimorphite, Smithsonite, Hydrozincite, zinc chlorite, limonite, zinc dolomite and zincocalcite; lead minerals and plumbiferous minerals are mainly galena, cerussite, anglesite, limonite and Coronadite; The minerals disseminated grain size are very fine and mineral dissemination characteristics are very complex ; expected theoretical recoveries for lead and zinc were 72% and 67% respectively. The results of this study provide basic data and theoretical basis for ore dressing. 展开更多
关键词 lead-zinc oxide ORE processing MINERALOGY material composition DISSEMINATED characteristics OCCURRENCE states
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Preparation of optimal entropy squeezing state of atomic qubit inside the cavity via two-photon process and manipulation of atomic qubit outside the cavity 被引量:1
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作者 周并举 彭朝晖 +2 位作者 贾春霞 姜春蕾 刘小娟 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期50-54,共5页
Considering two atomic qubits initially in Bell states, we send one qubit into a vacuum cavity with two-photon resonance and leave the other one outside. Using quantum information entropy squeezing theory, the time ev... Considering two atomic qubits initially in Bell states, we send one qubit into a vacuum cavity with two-photon resonance and leave the other one outside. Using quantum information entropy squeezing theory, the time evolutions of the entropy squeezing factor of the atomic qubit inside the cavity are discussed for two cases, i.e., before and after rotation and measurement of the atomic qubit outside the cavity. It is shown that the atomic qubit inside the cavity has no entropy squeezing phenomenon and is always in a decoherent state before the operating atomic qubit outside the cavity. However,the periodical entropy squeezing phenomenon emerges and the optimal entropy squeezing state can be prepared for the atomic qubit inside the cavity by adjusting the rotation angle, choosing the interaction time between the atomic qubit and the cavity, controlling the probability amplitudes of subsystem states. Its physical essence is cutting the entanglement between the atomic qubit and its environment, causing the atomic qubit inside the cavity to change from the initial decoherent state into maximum coherent superposition state, which is a possible way of recovering the coherence of a single atomic qubit in the noise environment. 展开更多
关键词 atomic qubit rotation operation optimal entropy squeezing state two-photon process
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CONTINUOUS TIME MIXED STATE BRANCHING PROCESSES AND STOCHASTIC EQUATIONS 被引量:1
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作者 Shukai CHEN Zenghu LI 《Acta Mathematica Scientia》 SCIE CSCD 2021年第5期1445-1473,共29页
A continuous time and mixed state branching process is constructed by a scaling limit theorem of two-type Galton-Watson processes.The process can also be obtained by the pathwise unique solution to a stochastic equati... A continuous time and mixed state branching process is constructed by a scaling limit theorem of two-type Galton-Watson processes.The process can also be obtained by the pathwise unique solution to a stochastic equation system.From the stochastic equation system we derive the distribution of local jumps and give the exponential ergodicity in Wasserstein-type distances of the transition semigroup.Meanwhile,we study immigration structures associated with the process and prove the existence of the stationary distribution of the process with immigration. 展开更多
关键词 mixed state branching process weak convergence stochastic equation system Wasserstein-type distance stationary distribution
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Research on the railway construction process quality model based on the state space method 被引量:1
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作者 Lu Shoudong Zhou Guohua +1 位作者 Chen Haifeng Zhao Guotang 《Engineering Sciences》 EI 2013年第5期54-60,共7页
In the ISO9000"input-output"process model,the concept of process quality is difficult to get the correct interpretation. From the"white box"theory of process,this paper puts forward the scientific ... In the ISO9000"input-output"process model,the concept of process quality is difficult to get the correct interpretation. From the"white box"theory of process,this paper puts forward the scientific meaning of the concept of process quality and the process quality model by taking the basic operating unit of 6M1E in the railway construction project for example. The basic operating unit system consists of technological natural process,operation process and management process;the process quality of the basic operating unit system depends on the interrelation and interaction among those three sub-processes,and also subjects to the impact of the external disturbance input factors. Finally,the cast-in-situ prestressed concrete continuous box girder construction process is utilized to elaborate the specific application of this theory in the quality management of the railway construction project. 展开更多
关键词 railway construction project "white box" model state transition equation process quality
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EXPERT SYSTEM FOR CONTROLLING THE STATE OF SINTERING PROCESS
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作者 Wang Haidong Jiang Bo (Department of Mineral Processing Engineering,Central South University of Technology,Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1999年第1期42-43,共2页
In order to control sintering process,improve permeability and stabilize burn through point, a control scheme which combines thermal state with permeability state is proposed, and an expert system for controlling sint... In order to control sintering process,improve permeability and stabilize burn through point, a control scheme which combines thermal state with permeability state is proposed, and an expert system for controlling sintering process state is developed, the software which includes about 1000 expert rules is successfully applied to off line control of sintering process. 展开更多
关键词 SINTERING process state CONTROL EXPERT SYSTEM
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Analyzing and Designing Business Processes Management System Based on Transformation of Instantiated Ontology’s State
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作者 YAO Qing WANG Haiyang 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1126-1131,共6页
The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find... The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find a unified representation and a flexible choreography of business processes. The main idea of the paper is the transformation of ontology's states, which are the most important scenarios of enterprises. The business activity composition, that is, case composition based on an AI technique, Case Based Reason (CBR), which is to solve new problems by retrieving solutions to previous problems, and then store the modified solution. The main interest in CBR relies on that it allows a system to avoid past failures and exploit past successes. 展开更多
关键词 ontology business process management (BPM) case based reason(CBR) state transform
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Coherent state evolution in a Raman dispersion process
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作者 杜建明 任刚 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期1-4,共4页
1. Introduction In quantum optics, optical frequency conversion is a typical nonlinear process and is worth studying, for example, a second harmonic frequency generation will generate a squeezed state.[1'2l In this ... 1. Introduction In quantum optics, optical frequency conversion is a typical nonlinear process and is worth studying, for example, a second harmonic frequency generation will generate a squeezed state.[1'2l In this work, we tackle the evolution of an initial coherent state in a Raman dispersion process which is also a nonlinear process. The process involves the inelastic scattering of a pho- ton when it is incident on a molecule. The photon loses some of its energy to the molecule or gains some from it, and so leaves the molecule with a lower or a higher frequency. The lower frequency components of the scattered radiation are called the Stokes lines and the higher frequency components are called the anti- Stokes lines. The Hamiltonian governing its dynamics is[3] 展开更多
关键词 Raman dispersion process integration within an ordered products of operators three-mode coherent state partition function
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MOMENTS OF CONTINUOUS-STATE BRANCHING PROCESSES IN LéVY RANDOM ENVIRONMENTS 被引量:1
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作者 Lina JI Xiangqi ZHENG 《Acta Mathematica Scientia》 SCIE CSCD 2019年第3期781-796,共16页
For continuous-state branching processes in Lévy random environments, the recursion of n-moments and the equivalent condition for the existence of general f-moments are established, where f is a positive continuo... For continuous-state branching processes in Lévy random environments, the recursion of n-moments and the equivalent condition for the existence of general f-moments are established, where f is a positive continuous function satisfying some standard conditions. 展开更多
关键词 Branching processes continuous-state MOMENTS RANDOM environment stochastic EQUATIONS
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