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Low-order harmonic generation of hydrogen molecular ion in laser field studied by the two-state model 被引量:1
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作者 Ling-Ling Du Guo-Li Wang +1 位作者 Peng-Cheng Li Xiao-Xin Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第11期459-465,共7页
The low-order harmonic generation of hydrogen molecular ion interacting with a linearly polarized laser field has been investigated theoretically by using a simple two-state model. The validity of the two-state model ... The low-order harmonic generation of hydrogen molecular ion interacting with a linearly polarized laser field has been investigated theoretically by using a simple two-state model. The validity of the two-state model is carefully examined by comparing the harmonic spectra of hydrogen molecular ion obtained from this model with those from the three-dimensional time-dependent Schr¨odinger equation. When combined with the Morlet transform of quantum time-frequency spectrum,the two-state model can be used to study the dynamical origin of the low-order harmonic generation of hydrogen molecular ion driven by low-frequency pulses. In addition, some interesting structures of the time profiles for low order harmonics are obtained. 展开更多
关键词 low order harmonic generation hydrogen molecule ion two state model
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State Modeling Based Prediction of Torsional Resonances for Horizontal-Axis Drive Train Wind Turbine 被引量:1
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作者 Rene Wamkeue Youssef Chrouro +1 位作者 Joseph Song-Mangelle Maurlce Nyobe-Yome 《Journal of Energy and Power Engineering》 2012年第11期1843-1847,共5页
This paper focuses on the state space modeling approach and output torques prediction of torsional vibrations for variable speed wind turbines. The multi-body system model under study is mainly comprised of a wind tur... This paper focuses on the state space modeling approach and output torques prediction of torsional vibrations for variable speed wind turbines. The multi-body system model under study is mainly comprised of a wind turbine, a three stage planetary gear box and an induction generator. The masses-springs approach of shaft system differential equations is developed from Newton's law and Lagrange formulas. For an easy comprehension for electrical engineers and tutorial purpose, an electrical equivalent circuit of the system is proposed by using mechanical and electrical components similarities. Extensive numerical simulations are performed to investigate system mechanical resonances and impacts of damping factors on the system dynamic and stability. 展开更多
关键词 state modeling wind turbine gear box mechanical resonances torsional vibrations stability and simulations.
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A network of conformational transitions in an unfolding process of HP-35 revealed by high-temperature MD simulation and a Markov state model
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作者 邵丹丹 高恺夫 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第1期175-181,共7页
An understanding of protein folding/unfolding processes has important implications for all biological processes, in- eluding protein degradation, protein translocation, aging, and diseases. All-atom molecular dynamics... An understanding of protein folding/unfolding processes has important implications for all biological processes, in- eluding protein degradation, protein translocation, aging, and diseases. All-atom molecular dynamics (MD) simulations are uniquely suitable for it because of their atomic level resolution and accuracy. However, limited by computational ca- pabilities, nowadays even for small and fast-folding proteins, all-atom MD simulations of protein folding still presents a great challenge. An alternative way is to study unfolding process using MD simulations at high temperature. High temper- ature provides more energy to overcome energetic barriers to unfolding, and information obtained from studying unfolding can shed light on the mechanism of folding. In the present study, a 1000-ns MD simulation at high temperature (500 K) was performed to investigate the unfolding process of a small protein, chicken villin headpiece (HP-35). To infer the folding mechanism, a Markov state model was also built from our simulation, which maps out six macrostates during the folding/unfolding process as well as critical transitions between them, revealing the folding mechanism unambiguously. 展开更多
关键词 molecular dynamics simulation Markov state model folding/unfolding HP-35
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Simulation studies of tungsten impurity behaviors during neon impurity seeding with tungsten bundled charge state model using SOLPS-ITER on EAST
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作者 Shanlu GAO Xiaoju LIU +8 位作者 Guozhong DENG Tingfeng MING Guoqiang LI Xuexi ZHANG Xiaodong WU Xiaohe WU Bang LI Haochen FAN Xiang GAO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第7期137-147,共11页
An investigation into tungsten(W)impurity behaviors with the update of the EAST lower W divertor for H-mode has been carried out using SOLPS-ITER.This work aims to study the effect of external neon(Ne)impurity seeding... An investigation into tungsten(W)impurity behaviors with the update of the EAST lower W divertor for H-mode has been carried out using SOLPS-ITER.This work aims to study the effect of external neon(Ne)impurity seeding on W impurity sputtering with the bundled charge state model.As the Ne seeding rate increases,plasma parameters,W concentration(C_(W)),and eroded W flux(Γ_(W)^(Ero))at both targets are compared and analyzed between the highly resolved bundled model‘jett’and the full W charge state model.The results indicate that‘jett’can produce divertor behaviors essentially in agreement with the full W charge state model.The bundled scheme with high resolution in low W charge states(<W^(20+))has no obvious effect on the Ne impurity distribution and thus little effect on W sputtering by Ne.Meanwhile,parametric scans of radial particle and thermal transport diffusivities(D_(⊥)andχ_(e,i))in the SOL are simulated using the‘jett’bundled model.The results indicate that the transport diffusivity variations have significant influences on the divertor parameters,especially for W impurity sputtering. 展开更多
关键词 tungsten impurity sputtering bundled charge state model transport diffusivity SOLPS-ITER
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A unified critical state model for geomaterials with an application to tunnelling 被引量:3
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作者 Hai-Sui Yu Pei-Zhi Zhuang Pin-Qiang Mo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第3期464-480,共17页
This paper is prepared in honour of Professor E.T.Brown for his outstanding contributions to rock mechanics and geotechnical engineering and also for his personal influence on the first author’s research career in ge... This paper is prepared in honour of Professor E.T.Brown for his outstanding contributions to rock mechanics and geotechnical engineering and also for his personal influence on the first author’s research career in geomechanics and geotechnical engineering.As a result,we have picked a topic that reflects two key research areas in which Professor E.T.Brown has made seminal contributions over a long and distinguished career.These two areas are concerned with the application of the critical state concept to modelling geomaterials and the analysis of underground excavation or tunnelling in geomaterials.Partially due to Professor Brown’s influence,the first author has also been conducting research in these two areas over many years.In particular,this paper aims to describe briefly the development of a unified critical state model for geomaterials together with an application to cavity contraction problems and tunnelling in soils. 展开更多
关键词 Critical state SOIL mechanics CONSTITUTIVE models Cavity CONTRACTION TUNNELLING in SOIL
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Steady-State Modeling of Heat Transfer on the Recovery System of Condensing Boiler
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作者 Joachim Ntonda Frederic Lontsi Francois Njock Bayock 《Journal of Power and Energy Engineering》 2021年第7期29-40,共12页
<span style="font-family:Verdana;">The increase of energy production is very important nowadays. It is necessary to improve the performance and efficiency of heat production facilities. The objective i... <span style="font-family:Verdana;">The increase of energy production is very important nowadays. It is necessary to improve the performance and efficiency of heat production facilities. The objective is to reduce pollutant emissions and regulate investment costs. One </span><span style="font-family:Verdana;">of the </span><span style="font-family:Verdana;">solution</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> is to control fuel and electricity consumption. </span><span style="font-family:Verdana;">This article develops a new model of simulation heat diffusion on the recovery system of condensing boiler. The method is based on the first and second thermodynamic systems. The Numerical discrete Model (NDM) was applied using MATLAB to simulate different characteristics of heat transfer in the recovery system. The result shows that the recovery unit can absorb the following temperatures;the range from 88°C to 90.7°C when the length of the tube is between respectively 110 and 111 m. the energy efficiency was between 0.55 and 0.57 which allowed confirming the model. This new model has some advantages such as;the use of an instantaneous calculation time. The heat recovered by the water tank can also serve as preheating different systems. One part of the heat recovered will be accumulated to be used as domestic hot water.</span> 展开更多
关键词 Heat Recovery STEADY-state Numerical Discrete model
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Application of a 2 Parameter Weibull Distribution in Modeling of State Holding Time in HIV/AIDS Transition Dynamics
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作者 Nahashon Mwirigi 《Open Journal of Modelling and Simulation》 2024年第4期130-158,共29页
This study investigates the application of the two-parameter Weibull distribution in modeling state holding times within HIV/AIDS progression dynamics. By comparing the performance of the Weibull-based Accelerated Fai... This study investigates the application of the two-parameter Weibull distribution in modeling state holding times within HIV/AIDS progression dynamics. By comparing the performance of the Weibull-based Accelerated Failure Time (AFT) model, Cox Proportional Hazards model, and Survival model, we assess the effectiveness of these models in capturing survival rates across varying gender, age groups, and treatment categories. Simulated data was used to fit the models, with model identification criteria (AIC, BIC, and R2) applied for evaluation. Results indicate that the AFT model is particularly sensitive to interaction terms, showing significant effects for older age groups (50 - 60 years) and treatment interaction, while the Cox model provides a more stable fit across all age groups. The Survival model displayed variability, with its performance diminishing when interaction terms were introduced, particularly in older age groups. Overall, while the AFT model captures the complexities of interactions in the data, the Cox model’s stability suggests it may be better suited for general analyses without strong interaction effects. The findings highlight the importance of model selection in survival analysis, especially in complex disease progression scenarios like HIV/AIDS. 展开更多
关键词 Weibull Distribution AFT model Cox Proportional Hazards HIV/AIDS state Holding Time Survival Analysis
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Energy Management Optimization Based on Aging Adaptive Functional State Model of Battery for Internal Combustion Engine Vehicles
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作者 Weiwei Kong Tianmao Cai +2 位作者 Yugong Luo Xiaomin Lian Fachao Jiang 《Automotive Innovation》 EI CSCD 2023年第1期62-75,共14页
This paper presents an energy management optimization system based on an adaptive functional state model of battery aging for internal combustion engine vehicles(ICEVs).First,the functional characteristics of batterie... This paper presents an energy management optimization system based on an adaptive functional state model of battery aging for internal combustion engine vehicles(ICEVs).First,the functional characteristics of batteries in ICEVs are investigated.Then,an adaptive functional state model is proposed to represent battery aging throughout the entire battery service life.A battery protection scheme is developed,including over-discharge and graded over-current protection to improve battery safety.A model-based energy management strategy is synthesized to comprehensively optimize fuel economy,battery life preservation,and vehicle performance.The performance of the proposed scheme was examined under comprehensive test scenarios based on field and bench tests.The results show that the proposed energy management algorithm can effectively improve fuel economy. 展开更多
关键词 Internal combustion engine vehicles Aging adaptive functional state model Energy management
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Four-Electron Systems in the Impurity Hubbard Model. Second Triplet State. Spectra of the System in the ν-Dimensional Lattice Zν
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作者 S. M. Tashpulatov R. T. Parmanova 《Journal of Applied Mathematics and Physics》 2023年第11期3393-3427,共35页
We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is in... We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is investigated. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model for the second triplet state of the system. The investigations show that the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues. 展开更多
关键词 Spectra of Four-Electron System Bound state Anti-Bound state Impurity Hubbard model Quintet state Singlet state Triplet state
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Stiffness Characteristics of a Basic Nonlinear Air Spring Model
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作者 Abdullah S. Alsuwaiyan 《World Journal of Engineering and Technology》 2024年第3期455-465,共11页
This study predicts the characteristics of a compressible polytropic air spring model. A second-order nonlinear autonomous air spring model is presented. The proposed model is based on the assumption that polytropic p... This study predicts the characteristics of a compressible polytropic air spring model. A second-order nonlinear autonomous air spring model is presented. The proposed model is based on the assumption that polytropic processes occur. Isothermal and isentropic compression and expansion of the air within the spring chambers are the two scenarios that are taken into consideration. In these situations, the air inside the spring chambers compresses and expands, resulting in nonlinear spring restoring forces. The MATLAB/Simulink software environment is used to build a numerical simulation model for the dynamic behavior of the air spring. To quantify the values of the stiffnesses of the proposed models, a numerical solution is run over time for various values of the design parameters. The isentropic process case has a higher dynamic air spring stiffness than the isothermal process case, according to the results. The size of the air spring chamber and the area of the air spring piston influence the air spring stiffness in both situations. It is demonstrated that the stiffness of the air spring increases linearly with increasing piston area and decreases nonlinearly with increasing air chamber length. As long as the ratio of the vibration’s amplitude to the air spring’s chamber length is small, there is good agreement in both scenarios between the linearized model and the full nonlinear model. This implies that linear modeling is a reasonable approximation of the complete nonlinear model in this particular scenario. 展开更多
关键词 Air Spring Dynamic Stiffness state Space Polytropic modeling Isentropic Process Isothermal Process
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Evaluating Behavioural Modelling Predictions in the Blue Shark (Prionace glauca) Enables Greater Insight on Habitat Use from Location only Argos Data
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作者 Riley Elliott Jingjing Zhang +2 位作者 Todd Dennis John Montgomery Craig Radford 《Research in Ecology》 2023年第3期31-48,共18页
The relationship between habitat and behaviour provides important information for species management.For large,free roaming,marine animals satellite tags provide high resolution information on movement,but such datase... The relationship between habitat and behaviour provides important information for species management.For large,free roaming,marine animals satellite tags provide high resolution information on movement,but such datasets are restricted due to cost.Extracting additional biologically important information from these data would increase utilisation and value.Several modelling approaches have been developed to identify behavioural states in tracking data.The objective of this study was to evaluate a behavioural state prediction model for blue shark(Prionace glauca)ARGOS surface location-only data.The novel nature of the six SPLASH satellite tags used enabled behavioural events to be identified in blue shark dive data and accurately mapped spatio-temporally along respective surface location-only tracks.Behavioural states modelled along the six surface location-only tracks were then tested against observed behavioural events to evaluate the model’s accuracy.Results showed that the Behavioural Change Point Analysis(BCPA)model augmented with K means clustering analysis performed well for predicting foraging behaviour(correct 86%of the time).Prediction accuracy was lower for searching(52%)and travelling(63%)behaviour,likely related to the numerical dominance of foraging events in dive data.The model’s validation for predicting foraging behaviour justified its application to nine additional surface location-only(SPOT tag)tracks,substantially increasing the utilisation of expensive and rare data.Results enabled the critical behavioural state of foraging,to be mapped throughout the entire home range of blue sharks,allowing drivers of critical habitat to be investigated.This validation strengthens the use of such modelling to interpret historic and future datasets,for blue sharks but also other species,contributing to conservational management. 展开更多
关键词 Blue shark Behavioural state modelling Satellite tracking Foraging behaviour Habitat use
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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:4
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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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Establishing formal state space models via quantization forquantum control systems 被引量:2
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作者 DongDaoyi ChenZonghai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期398-402,共5页
Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of qua... Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of quantum control systems must accord with Schrdinger equations, so it is foremost to obtain Hamiltonian operators of systems. There are corresponding relations between operators of quantum systems and corresponding physical quantities of classical systems, such as momentum, energy and Hamiltonian, so Schrdinger equation models of corresponding quantum control systems via quantization could been obtained from classical control systems, and then establish formal state space models through the suitable transformation from Schrdinger equations for these quantum control systems. This method provides a new kind of path for modeling in quantum control. 展开更多
关键词 quantum control systems formal state space models quantization.
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Application of the state space model to the system of wave energy conversion Analytical method for wave forces on singleoscillating rectangular buoy 被引量:1
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作者 ZHENGYonghong SUNXiaoyan +2 位作者 YOUYage SHENYongming WUBijun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第4期757-765,共9页
A new analytical method is proposed to analyze the force acting on a rectangular oscillating buoy due to linear waves.In the method a new analytical expression for the diffraction velocity potential is obtained first ... A new analytical method is proposed to analyze the force acting on a rectangular oscillating buoy due to linear waves.In the method a new analytical expression for the diffraction velocity potential is obtained first by use of theeigenfunction expansion method and then the wave excitation force is calculated by use of the known incident wavepotential and the diffraction potential. Compared with the classical analytical method, it can be seen that the presentmethod is simpler for a two-dimensional problem due to the comparable effort needed for the computation ofdiffraction potential and for that of radiated potential. To verify the correctness of the method, a classical example inthe reference is recomputed and the obtained results are in good accordance with those by use of other methods,which shows that the present method is correct. 展开更多
关键词 state space model oscillating buoy device HEAVE wave force analytical method
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Quantum-dot Semiconductor Optical Amplifiers in State Space Model 被引量:1
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作者 Hussein Taleb Kambiz Abedi Saeed Golmohammadi 《计算物理》 CSCD 北大核心 2013年第4期605-612,共8页
A state space model(SSM) is derived for quantum-dot semiconductor optical amplifiers(QD-SOAs).Rate equations of QD-SOA are formulated in the form of state update equations,where average occupation probabilities along ... A state space model(SSM) is derived for quantum-dot semiconductor optical amplifiers(QD-SOAs).Rate equations of QD-SOA are formulated in the form of state update equations,where average occupation probabilities along QD-SOA cavity are considered as state variables of the system.Simulations show that SSM calculates QD-SOA′s static and dynamic characteristics with high accuracy. 展开更多
关键词 QUANTUM-DOT rate equation model semiconductor optical amplifiers state space model
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Design Criterion for Fixture Layout Based on the State Space Model in M ultistation Assembly Processes 被引量:2
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作者 张磊 周一帆 +1 位作者 张志胜 史金飞 《Journal of Donghua University(English Edition)》 EI CAS 2013年第3期175-181,共7页
The fixture layout is crucial to assure the product quality in a multistation assembly process (MAP). A well-designed fixture layout will make the final product's variability be insensitive to the fixture variation... The fixture layout is crucial to assure the product quality in a multistation assembly process (MAP). A well-designed fixture layout will make the final product's variability be insensitive to the fixture variation inputs. As the basis of the fixture layout design, the design criterion plays an important role in the effectiveness of a solution and the optimization efficiency. In this paper, an effective and efficient design criterion is proposed for the fixture layout with a fixed reference point (FRP) in an MAP. First of all, a state space model for the individual port's variation propagation and accumulation is developed, which is the mathematical foundation of the proposed criterion. Then, based on this model, a novel design criterion used to evaluate the performance of the fixture layout is proposed for the fixture layout with an FRP. Finally, a method extracted from the proposed design criterion is developed for quick fixture layout design. A four-station assembly process is used to validate the effectiveness and efficiency of the proposed models and methods. 展开更多
关键词 state space model covariance matrix fixed reference point (FRP) largest distance
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Remaining Useful Life Model and Assessment of Mechanical Products: A Brief Review and a Note on the State Space Model Method 被引量:9
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作者 Yawei Hu Shujie Liu +1 位作者 Huitian Lu Hongchao Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第1期11-30,共20页
The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). ... The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). These studies incorporated many di erent models, algorithms, and techniques for modeling and assessment. In this paper, methods of RUL assessment are summarized and expounded upon using two major methods: physics model based and data driven based methods. The advantages and disadvantages of each of these methods are deliberated and compared as well. Due to the intricacy of failure mechanism in system, and di culty in physics degradation observation, RUL assessment based on observations of performance variables turns into a science in evaluating the degradation. A modeling method from control systems, the state space model(SSM), as a first order hidden Markov, is presented. In the context of non-linear and non-Gaussian systems, the SSM methodology is capable of performing remaining life assessment by using Bayesian estimation(sequential Monte Carlo). Being e ective for non-linear and non-Gaussian dynamics, the methodology can perform the assessment recursively online for applications in CBM(condition based maintenance), PHM(prognostics and health management), remanufacturing, and system performance reliability. Finally, the discussion raises concerns regarding online sensing data for SSM modeling and assessment of RUL. 展开更多
关键词 REMAINING useful life state space model Online ASSESSMENT BAYESIAN estimation Particle filter REMANUFACTURING
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Disturbed state concept as unified constitutive modeling approach 被引量:4
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作者 Chandrakant S.Desai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第3期277-293,共17页
A unified constitutive modeling approach is highly desirable to characterize a wide range of engineeringmaterials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creepdeforma... A unified constitutive modeling approach is highly desirable to characterize a wide range of engineeringmaterials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creepdeformations, stress path, volume change, microcracking leading to fracture, failure and softening,stiffening, and mechanical and environmental forces. There are hardly available such unified models. Thedisturbed state concept (DSC) is considered to be a unified approach and is able to provide materialcharacterization for almost all of the above factors. This paper presents a description of the DSC, andstatements for determination of parameters based on triaxial, multiaxial and interface tests. Statementsof DSC and validation at the specimen level and at the boundary value problem levels are also presented.An extensive list of publications by the author and others is provided at the end. The DSC is considered tobe a unique and versatile procedure for modeling behaviors of engineering materials and interfaces. 2016 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. This is an open access article under the CC BY-NC-ND license 展开更多
关键词 Disturbed state concept (DSC)Constitutive model Parameters Soils Interfaces Validations
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Estimating Hydrogeological Parameters in Covered Carbonate Rocks Using a Discrete-State Compartment Model and Environmental Tritium 被引量:1
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作者 马志远 周寅康 Matthias Hinderer 《Journal of China University of Mining and Technology》 2002年第1期30-34,共5页
Nowadays, isotope environmental technique tends to be used as a reconnaissance tool , both qualitative and quantitative, to calculate the aquifer parameters particularly in carbonate rock aquifers. But, the hetero... Nowadays, isotope environmental technique tends to be used as a reconnaissance tool , both qualitative and quantitative, to calculate the aquifer parameters particularly in carbonate rock aquifers. But, the heterogeneous flow is still problematic when Lumped parameter Models are usually used to calculate the residence times and hydraulic parameters. However, Discrete State Compartment Model can provide a powerful model to heterogeneous medium. One such study was carried on in Dazha valley, where the environmental tritium was used as a tracer for determining hydrogeological parameters based on a discrete state compartment model 展开更多
关键词 discrete state compartment model environmental tritium covered carbonate rocks hydraulic parameters residence time concentration of tritium tracer
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A Generalized State Space Average Model for Parallel DC-to-DC Converters 被引量:1
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作者 Hasan Alrajhi 《Computer Systems Science & Engineering》 SCIE EI 2022年第5期717-734,共18页
The high potentiality of integrating renewable energies,such as photovoltaic,into a modern electrical microgrid system,using DC-to-DC converters,raises some issues associated with controller loop design and system sta... The high potentiality of integrating renewable energies,such as photovoltaic,into a modern electrical microgrid system,using DC-to-DC converters,raises some issues associated with controller loop design and system stability.The generalized state space average model(GSSAM)concept was consequently introduced to design a DC-to-DC converter controller in order to evaluate DC-to-DC converter performance and to conduct stability studies.This paper presents a GSSAM for parallel DC-to-DC converters,namely:buck,boost,and buck-boost converters.The rationale of this study is that modern electrical systems,such as DC networks,hybrid microgrids,and electric ships,are formed by parallel DC-to-DC converters with separate DC input sources.Therefore,this paper proposes a GSSAM for any number of parallel DC-to-DC converters.The proposed GSSAM is validated and investigated in a time-domain simulation environment,namely a MATLAB/SIMULINK.The study compares the steady-state,transient,and oscillatory performance of the state-space average model with a fully detailed switching model. 展开更多
关键词 Parallel DC-to-DC converters generalized state space average model buck converters boost converters buck-boost converters
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