In this paper, we propose an interactive method for solving the multilevel linear programming problems based on the intuitionistic fuzzy set theory. Firstly, the membership function and the non-membership function are...In this paper, we propose an interactive method for solving the multilevel linear programming problems based on the intuitionistic fuzzy set theory. Firstly, the membership function and the non-membership function are introduced to describe the uncertainty of the decision makers. Secondly, a satisfactory solution is derived by updating the minimum satisfactory degrees with considerations of the overall satisfactory balance among all levels. In addition, the steps of the proposed method are given in this paper. Finally, numerical examples illustrate the feasibility of this method.展开更多
The glutenite reservoir is strongly heterogeneous due to the random distribution of gravels, making it challenging to perform hydraulic fracturing effectively. To solve this issue, it is essential to study interaction...The glutenite reservoir is strongly heterogeneous due to the random distribution of gravels, making it challenging to perform hydraulic fracturing effectively. To solve this issue, it is essential to study interaction behavior between hydraulic fractures(HFs) and gravels. A coupled hydro-mechanical model is proposed for HF propagation in glutenite using a grain-based discrete element method. This paper first investigates the dynamic evolution of HFs in glutenite, then analyzes the influences of various factors such as horizontal stress difference(Δσ), minimum horizontal stress(σh), gravel content(Vg), gravel size(dg), and stiffness ratio of gravel to matrix(Rs) on HF propagation geometries. Results show that penetrating the gravel is the primary HF-gravel interaction behavior, which follows sequential and staggered initiation modes. Bypassing the gravel is the secondary behavior, which obeys the sequential initiation mode and occurs when the orientation of the gravel boundary is inclined to the maximum horizontal stress(σH). An offset along the gravel boundary is usually formed while penetrating gravels, and the offsets may cause fracture widths to decrease by 37.8%-84.4%. Even if stress dominates the direction of HF propagation, HFs still tend to deflect within gravels. The deviation angle from σH decreases with rising Δσand increases with the increase of dgand Rs. Additionally, intra-gravel shear HFs(IGS-HFs) are prone to be generated in coarse-grained glutenite under high Δσ, while more gravel-bypassing shear HFs(GBSHFs) tend to be created in argillaceous glutenite with high Rsthan in sandy glutenite with low Rs. The findings above prompt the emergence of a novel HF propagation pattern in glutenite, which helps to understand the real HF geometries and to provide theoretical guidance for treatments in the field.展开更多
Measurement-while-drilling(MWD)and guidance technologies have been extensively deployed in the exploitation of oil,natural gas,and other energy resources.Conventional control approaches are plagued by challenges,inclu...Measurement-while-drilling(MWD)and guidance technologies have been extensively deployed in the exploitation of oil,natural gas,and other energy resources.Conventional control approaches are plagued by challenges,including limited anti-interference capabilities and the insufficient generalization of decision-making experience.To address the intricate problem of directional well trajectory control,an intelligent algorithm design framework grounded in the high-level interaction mechanism between geology and engineering is put forward.This framework aims to facilitate the rapid batch migration and update of drilling strategies.The proposed directional well trajectory control method comprehensively considers the multi-source heterogeneous attributes of drilling experience data,leverages the generative simulation of the geological drilling environment,and promptly constructs a directional well trajectory control model with self-adaptive capabilities to environmental variations.This construction is carried out based on three hierarchical levels:“offline pre-drilling learning,online during-drilling interaction,and post-drilling model transfer”.Simulation results indicate that the guidance model derived from this method demonstrates remarkable generalization performance and accuracy.It can significantly boost the adaptability of the control algorithm to diverse environments and enhance the penetration rate of the target reservoir during drilling operations.展开更多
In order to implement the optimal design of the indoor thermal comfort based on the numerical modeling method, the numerical calculation platform is combined seamlessly with the data-processing platform, and an intera...In order to implement the optimal design of the indoor thermal comfort based on the numerical modeling method, the numerical calculation platform is combined seamlessly with the data-processing platform, and an interactive numerical calculation platform which includes the functions of numerical simulation and optimization is established. The artificial neural network (ANN) and the greedy strategy are introduced into the hill-climbing pattern heuristic search process, and the optimizing search direction can be predicted by using small samples; when searching along the direction using the greedy strategy, the optimal values can be quickly approached. Therefore, excessive external calling of the numerical modeling process can be avoided, and the optimization time is decreased obviously. The experimental results indicate that the satisfied output parameters of air conditioning can be quickly given out based on the interactive numerical calculation platform and the improved search method, and the optimization for indoor thermal comfort can be completed.展开更多
Objective:To evaluate the therapeutic efficacy of the umbilical acupuncture’s“Wind-Thunder Interaction Method”in treating schizophrenia(SCH)patients with liver stagnation and spleen deficiency.Methods:A total of 12...Objective:To evaluate the therapeutic efficacy of the umbilical acupuncture’s“Wind-Thunder Interaction Method”in treating schizophrenia(SCH)patients with liver stagnation and spleen deficiency.Methods:A total of 120 SCH patients with liver stagnation and spleen deficiency were selected and evenly divided by ball drawing.The umbilical acupuncture group received the“Wind-Thunder Interaction Method”,while the Western medicine group received pure Western medicine treatment.The outcomes were compared in terms of efficacy and other indicators.Results:The umbilical acupuncture group showed a higher total effective rate,a decrease in disease symptom scores,lower scores on the side effect rating scale,improved cognitive function scores,and excellent laboratory indicators,with p<0.05 between the groups.Conclusion:The“Wind-Thunder Interaction Method”of umbilical acupuncture demonstrated a relatively high effectiveness in treating SCH patients with liver stagnation and spleen deficiency,alleviating symptoms,reducing side effects,improving cognitive function,and facilitating the recovery of neuro-vascular regulatory peptide groups.展开更多
This paper considers multiobjective integer programming problems involving random variables in constraints. Using the concept of simple recourse, the formulated multiobjective stochastic simple recourse problems are t...This paper considers multiobjective integer programming problems involving random variables in constraints. Using the concept of simple recourse, the formulated multiobjective stochastic simple recourse problems are transformed into deterministic ones. For solving transformed deterministic problems efficiently, we also introduce genetic algorithms with double strings for nonlinear integer programming problems. Taking into account vagueness of judgments of the decision maker, an interactive fuzzy satisficing method is presented. In the proposed interactive method, after determineing the fuzzy goals of the decision maker, a satisficing solution for the decision maker is derived efficiently by updating the reference membership levels of the decision maker. An illustrative numerical example is provided to demonstrate the feasibility and efficiency of the proposed method.展开更多
Multiobjective Programming (MOP) has become famous among many researchers due to more practical and realistic applications. A lot of methods have been proposed especially during the past four decades. In this paper, w...Multiobjective Programming (MOP) has become famous among many researchers due to more practical and realistic applications. A lot of methods have been proposed especially during the past four decades. In this paper, we develop a new algorithm based on a new approach to solve MOP by starting from a utopian point, which is usually infeasible, and moving towards the feasible region via stepwise movements and a simple continuous interaction with decision maker. We consider the case where all objective functions and constraints are linear. The implementation of the pro-posed algorithm is demonstrated by two numerical examples.展开更多
English has been a subject in the university classroom since the 1980s.This subject helps produce more excellent talents in economics,politics,and culture who are proficient in English language in China,and enable our...English has been a subject in the university classroom since the 1980s.This subject helps produce more excellent talents in economics,politics,and culture who are proficient in English language in China,and enable our country to better integrate with the global economy.At the same time,the relationship between our country and the international community has become closer.However,the social environment is constantly developing and changing.The traditional teaching methods can be said to be ineffective and associated with many shortcomings.Traditional teaching methods were used in the English lessons.Under this teaching mode,students were the passive subjects on the receiving end of what have been taught.The teacher was always talking in the classroom and the students were listening.This teaching style also affects the effectiveness of learning.Compared with traditional teaching,interactive teaching method has its unique advantages.It is a new teaching mode and under this teaching mode,students can actively communicate with teachers in the classroom to complete learning tasks.The initiative to perform self-directed learning is also greatly improved,and the students’English proficiency can be improved.展开更多
The Balise Transmission Module(BTM)unit of the on-board train control system is a crucial component.Due to its unique installation position and complex environment,this unit has a higher fault rate within the on-board...The Balise Transmission Module(BTM)unit of the on-board train control system is a crucial component.Due to its unique installation position and complex environment,this unit has a higher fault rate within the on-board train control system.To conduct fault prediction for the BTM unit based on actual fault data,this study proposes a prediction method combining reliability statistics and machine learning,and achieves the fusion of prediction results from different dimensions through multi-method interactive validation.Firstly,a method for predicting equipment fault time targeting batch equipment is introduced.This method utilizes reliability statistics to construct a model of the remaining faultless operating time distribution considering uncertainty,thereby predicting the remaining faultless operating probability of the BTM unit.Secondly,considering the complexity of the BTM unit’s fault mechanism,the small sample size of fault cases,and the potential presence of multiple fault features in fault text records,an individual-oriented fault prediction method based on Bayesian-optimized Gradient Boosting Regression Tree(Bayes-GBRT)is proposed.This method achieves better prediction results compared to linear regression algorithms and random forest regression algorithms,with an average absolute error of only 0.224 years for predicting the fault time of this type of equipment.Finally,a multi-method interactive validation approach is proposed,enabling the fusion and validation of multi-dimensional results.The results indicate that the predicted fault time and the actual fault time conform to a log-normal distribution,and the parameter estimation results are basically consistent,verifying the accuracy and effectiveness of the prediction results.The above research findings can provide technical support for the maintenance and modification of BTM units,effectively reducing maintenance costs and ensuring the safe operation of high-speed railway,thus having practical engineering value for preventive maintenance.展开更多
In the stage of senior high school education, senior high school Chinese is an important basic subject. There are various teaching methods in Chinese teaching in senior high schools, and interactive teaching method is...In the stage of senior high school education, senior high school Chinese is an important basic subject. There are various teaching methods in Chinese teaching in senior high schools, and interactive teaching method is a common teaching method. Through good interaction between teachers and students, an efficient Chinese classroom can be constructed. Students can learn and master more Chinese knowledge in the limited classroom learning time. At the same time, the Chinese interactive teaching method can also expand the students thinking of language and literature study, so that students can be inspired and educated through the interactive communication between teachers and students and between students. It is beneficial for students to study Chinese more deeply and comprehensively and further improve their Chinese learning level.展开更多
At present,in the high school English classroom teaching,there are still some problems,which is an obstacle to hinder the smooth development of English teaching,in this case,in order to improve the efficiency of the h...At present,in the high school English classroom teaching,there are still some problems,which is an obstacle to hinder the smooth development of English teaching,in this case,in order to improve the efficiency of the high school English teaching,the use of this method has been used which can largely improve the students’interest in learning,to build interesting class.This paper analyzes the application of interactive teaching method in English classroom teaching for reference.展开更多
The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident...The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident wave into equivalent loads on the cutoff boundaries. The wave method has high precision, but the implementation is complicated, especially for three-dimensional models. By deducing another form of equivalent input seismic loads in the fi nite element model, a new seismic wave input method is proposed. In the new method, by imposing the displacements of the free wave fi eld on the nodes of the substructure composed of elements that contain artifi cial boundaries, the equivalent input seismic loads are obtained through dynamic analysis of the substructure. Subsequently, the equivalent input seismic loads are imposed on the artifi cial boundary nodes to complete the seismic wave input and perform seismic analysis of the soil-structure dynamic interaction model. Compared with the wave method, the new method is simplifi ed by avoiding the complex processes of calculating the equivalent input seismic loads. The validity of the new method is verifi ed by the dynamic analysis numerical examples of the homogeneous and layered half space under vertical and oblique incident seismic waves.展开更多
To improve the land surface simulation in the arid and semi-arid areas of northern China, the observational data from two field experiments in Dunhuang and Tongyu are used to optimize the parameters in the land surfac...To improve the land surface simulation in the arid and semi-arid areas of northern China, the observational data from two field experiments in Dunhuang and Tongyu are used to optimize the parameters in the land surface model, BATS, through calibration with the multicriteria method. Sensitivity analysis to the parameters in Dunhuang and Tongyu indicates that different parameters need to be calibrated in two sites with different environmental and climate regimes. Comparison of observed sensible heat flux, latent heat flux, and ground surface temperature with the simulated ones shows the simulations with the optimized parameters have been substantially improved. Especially, the holistic simulations with the calibration of the parameter values are much closer to the observations in the arid region (Dunhuang), and the energy partition with the calibrated parameters can also be simulated well in the semi-arid region (Tongyu). Whole results demonstrate that the parameter calibration of the land surface model is important when the model is to be used to investigate the land-air interaction.展开更多
Fluid-structure interaction (FSI) is essentially a dynamic phenomenon and always exists in fluid-filled pipe system. The four-equation model, which has been proved to be effective to describe and predict the phenome...Fluid-structure interaction (FSI) is essentially a dynamic phenomenon and always exists in fluid-filled pipe system. The four-equation model, which has been proved to be effective to describe and predict the phenomenon of FSI due to friction coupling and Poisson coupling being taken into account, is utilized to describe the FSI of fluid-filled pipe system. Terse compatibility equations are educed by the method of characteristics (MOC) to describe the fluid-filled pipe system. To shorten computing time needed to get the solutions under the condition of keeping accuracy requirement, two steps are adopted, firstly the time step Δt and divided number of the straight pipe are optimized, sec-ondly the mesh spacing Δz close to boundary is subdivided in several submeshes automatically ac-cording to the speed gradient of fluid. The mathematical model and arithmetic are validated by com-parisons between simulation solutions of two straight pipe systems and experiment known from lit-erature.展开更多
In this study, an advanced Lagrangian vortex- boundary element method is applied to simulate the unsteady impeller-diffuser interactions in a diffuser pump not only for design but also for off-design considerations. I...In this study, an advanced Lagrangian vortex- boundary element method is applied to simulate the unsteady impeller-diffuser interactions in a diffuser pump not only for design but also for off-design considerations. In velocity calculations based on the Biot-Savart law we do not have to grid large portions of the flow field and the calculation points are concentrated in the regions where vorticity is present. Lagrangian representation of the evolving vorticity field is well suited to moving boundaries. An integral pressure equation shows that the pressure distribution can be estimated directly from the instantaneous velocity and vorticity field. The numerical results are compared with the experimental data and the comparisons show that the method used in this study can provide us insight into the complicated unsteady impeller-diffuser interaction phenomena in a diffuser pump.展开更多
Based on the transfer matrix method and the virtual source simulation technique, this paper proposes a novel semi-analytical and semi-numerical method for solving 2-D sound- structure interaction problems under a harm...Based on the transfer matrix method and the virtual source simulation technique, this paper proposes a novel semi-analytical and semi-numerical method for solving 2-D sound- structure interaction problems under a harmonic excitation.Within any integration segment, as long as its length is small enough,along the circumferential curvilinear coordinate,the non- homogeneous matrix differential equation of an elastic ring of complex geometrical shape can be rewritten in terms of the homogeneous one by the method of extended homogeneous capacity proposed in this paper.For the exterior fluid domain,the multi-circular virtual source simulation technique is adopted.The source density distributed on each virtual circular curve may be ex- panded as the Fourier's series.Combining with the inverse fast Fourier transformation,a higher accuracy and efficiency method for solving 2-D exterior Helmholtz's problems is presented in this paper.In the aspect of solution to the coupling equations,the state vectors of elastic ring induced by the given harmonic excitation and generalized forces of coefficients of the Fourier series can be obtained respectively by using a high precision integration scheme combined with the method of extended homogeneous capacity put forward in this paper.According to the superposition princi- ple and compatibility conditions at the interface between the elastic ring and fluid,the algebraic equation of system can be directly constructed by using the least square approximation.Examples of acoustic radiation from two typical fluid-loaded elastic rings under a harmonic concentrated force are presented.Numerical results show that the method proposed is more efficient than the mixed FE-BE method in common use.展开更多
Consideration of structure-foundation-soil dynamic interaction is a basic requirement in the evaluation of the seismic safety of nuclear power facilities. An efficient and accurate dynamic interaction numerical model ...Consideration of structure-foundation-soil dynamic interaction is a basic requirement in the evaluation of the seismic safety of nuclear power facilities. An efficient and accurate dynamic interaction numerical model in the time domain has become an important topic of current research. In this study, the scaled boundary finite element method (SBFEM) is improved for use as an effective numerical approach with good application prospects. This method has several advantages, including dimensionality reduction, accuracy of the radial analytical solution, and unlike other boundary element methods, it does not require a fundamental solution. This study focuses on establishing a high performance scaled boundary finite element interaction analysis model in the time domain based on the acceleration unit-impulse response matrix, in which several new solution techniques, such as a dimensionless method to solve the interaction force, are applied to improve the numerical stability of the actual soil parameters and reduce the amount of calculation. Finally, the feasibility of the time domain methods are illustrated by the response of the nuclear power structure and the accuracy of the algorithms are dynamically verified by comparison with the refinement of a large-scale viscoelastic soil model.展开更多
Fluid-Structure Interaction(FSI) caused by fluid impacting onto a flexible structure commonly occurs in naval architecture and ocean engineering. Research on the problem of wave-structure interaction is important to e...Fluid-Structure Interaction(FSI) caused by fluid impacting onto a flexible structure commonly occurs in naval architecture and ocean engineering. Research on the problem of wave-structure interaction is important to ensure the safety of offshore structures. This paper presents the Moving Particle Semi-implicit and Finite Element Coupled Method(MPS-FEM) to simulate FSI problems. The Moving Particle Semi-implicit(MPS) method is used to calculate the fluid domain, while the Finite Element Method(FEM) is used to address the structure domain. The scheme for the coupling of MPS and FEM is introduced first. Then, numerical validation and convergent study are performed to verify the accuracy of the solver for solitary wave generation and FSI problems. The interaction between the solitary wave and an elastic structure is investigated by using the MPS-FEM coupled method.展开更多
基金Supported by the National Natural Science Foundation of China(71471140,71171150,71103135)
文摘In this paper, we propose an interactive method for solving the multilevel linear programming problems based on the intuitionistic fuzzy set theory. Firstly, the membership function and the non-membership function are introduced to describe the uncertainty of the decision makers. Secondly, a satisfactory solution is derived by updating the minimum satisfactory degrees with considerations of the overall satisfactory balance among all levels. In addition, the steps of the proposed method are given in this paper. Finally, numerical examples illustrate the feasibility of this method.
基金supported by the National Natural Science Foundation of China(Grant No.52304003)the Natural Science Foundation of Sichuan Province(Grant No.2024NSFSC0961)the Postdoctoral Fellowship Program of CPSF(Grant No.GZB20230090).
文摘The glutenite reservoir is strongly heterogeneous due to the random distribution of gravels, making it challenging to perform hydraulic fracturing effectively. To solve this issue, it is essential to study interaction behavior between hydraulic fractures(HFs) and gravels. A coupled hydro-mechanical model is proposed for HF propagation in glutenite using a grain-based discrete element method. This paper first investigates the dynamic evolution of HFs in glutenite, then analyzes the influences of various factors such as horizontal stress difference(Δσ), minimum horizontal stress(σh), gravel content(Vg), gravel size(dg), and stiffness ratio of gravel to matrix(Rs) on HF propagation geometries. Results show that penetrating the gravel is the primary HF-gravel interaction behavior, which follows sequential and staggered initiation modes. Bypassing the gravel is the secondary behavior, which obeys the sequential initiation mode and occurs when the orientation of the gravel boundary is inclined to the maximum horizontal stress(σH). An offset along the gravel boundary is usually formed while penetrating gravels, and the offsets may cause fracture widths to decrease by 37.8%-84.4%. Even if stress dominates the direction of HF propagation, HFs still tend to deflect within gravels. The deviation angle from σH decreases with rising Δσand increases with the increase of dgand Rs. Additionally, intra-gravel shear HFs(IGS-HFs) are prone to be generated in coarse-grained glutenite under high Δσ, while more gravel-bypassing shear HFs(GBSHFs) tend to be created in argillaceous glutenite with high Rsthan in sandy glutenite with low Rs. The findings above prompt the emergence of a novel HF propagation pattern in glutenite, which helps to understand the real HF geometries and to provide theoretical guidance for treatments in the field.
基金supported by the National Key R&D Program of China(No.2019YFA0708304)the CNPC Innovation Fund(No.2022DQ02-0609)the Scientific research and technology development Project of CNPC(No.2022DJ4507).
文摘Measurement-while-drilling(MWD)and guidance technologies have been extensively deployed in the exploitation of oil,natural gas,and other energy resources.Conventional control approaches are plagued by challenges,including limited anti-interference capabilities and the insufficient generalization of decision-making experience.To address the intricate problem of directional well trajectory control,an intelligent algorithm design framework grounded in the high-level interaction mechanism between geology and engineering is put forward.This framework aims to facilitate the rapid batch migration and update of drilling strategies.The proposed directional well trajectory control method comprehensively considers the multi-source heterogeneous attributes of drilling experience data,leverages the generative simulation of the geological drilling environment,and promptly constructs a directional well trajectory control model with self-adaptive capabilities to environmental variations.This construction is carried out based on three hierarchical levels:“offline pre-drilling learning,online during-drilling interaction,and post-drilling model transfer”.Simulation results indicate that the guidance model derived from this method demonstrates remarkable generalization performance and accuracy.It can significantly boost the adaptability of the control algorithm to diverse environments and enhance the penetration rate of the target reservoir during drilling operations.
基金Sponsored by the National Program"973"Project (2005CB623906)
文摘In order to implement the optimal design of the indoor thermal comfort based on the numerical modeling method, the numerical calculation platform is combined seamlessly with the data-processing platform, and an interactive numerical calculation platform which includes the functions of numerical simulation and optimization is established. The artificial neural network (ANN) and the greedy strategy are introduced into the hill-climbing pattern heuristic search process, and the optimizing search direction can be predicted by using small samples; when searching along the direction using the greedy strategy, the optimal values can be quickly approached. Therefore, excessive external calling of the numerical modeling process can be avoided, and the optimization time is decreased obviously. The experimental results indicate that the satisfied output parameters of air conditioning can be quickly given out based on the interactive numerical calculation platform and the improved search method, and the optimization for indoor thermal comfort can be completed.
文摘Objective:To evaluate the therapeutic efficacy of the umbilical acupuncture’s“Wind-Thunder Interaction Method”in treating schizophrenia(SCH)patients with liver stagnation and spleen deficiency.Methods:A total of 120 SCH patients with liver stagnation and spleen deficiency were selected and evenly divided by ball drawing.The umbilical acupuncture group received the“Wind-Thunder Interaction Method”,while the Western medicine group received pure Western medicine treatment.The outcomes were compared in terms of efficacy and other indicators.Results:The umbilical acupuncture group showed a higher total effective rate,a decrease in disease symptom scores,lower scores on the side effect rating scale,improved cognitive function scores,and excellent laboratory indicators,with p<0.05 between the groups.Conclusion:The“Wind-Thunder Interaction Method”of umbilical acupuncture demonstrated a relatively high effectiveness in treating SCH patients with liver stagnation and spleen deficiency,alleviating symptoms,reducing side effects,improving cognitive function,and facilitating the recovery of neuro-vascular regulatory peptide groups.
文摘This paper considers multiobjective integer programming problems involving random variables in constraints. Using the concept of simple recourse, the formulated multiobjective stochastic simple recourse problems are transformed into deterministic ones. For solving transformed deterministic problems efficiently, we also introduce genetic algorithms with double strings for nonlinear integer programming problems. Taking into account vagueness of judgments of the decision maker, an interactive fuzzy satisficing method is presented. In the proposed interactive method, after determineing the fuzzy goals of the decision maker, a satisficing solution for the decision maker is derived efficiently by updating the reference membership levels of the decision maker. An illustrative numerical example is provided to demonstrate the feasibility and efficiency of the proposed method.
文摘Multiobjective Programming (MOP) has become famous among many researchers due to more practical and realistic applications. A lot of methods have been proposed especially during the past four decades. In this paper, we develop a new algorithm based on a new approach to solve MOP by starting from a utopian point, which is usually infeasible, and moving towards the feasible region via stepwise movements and a simple continuous interaction with decision maker. We consider the case where all objective functions and constraints are linear. The implementation of the pro-posed algorithm is demonstrated by two numerical examples.
文摘English has been a subject in the university classroom since the 1980s.This subject helps produce more excellent talents in economics,politics,and culture who are proficient in English language in China,and enable our country to better integrate with the global economy.At the same time,the relationship between our country and the international community has become closer.However,the social environment is constantly developing and changing.The traditional teaching methods can be said to be ineffective and associated with many shortcomings.Traditional teaching methods were used in the English lessons.Under this teaching mode,students were the passive subjects on the receiving end of what have been taught.The teacher was always talking in the classroom and the students were listening.This teaching style also affects the effectiveness of learning.Compared with traditional teaching,interactive teaching method has its unique advantages.It is a new teaching mode and under this teaching mode,students can actively communicate with teachers in the classroom to complete learning tasks.The initiative to perform self-directed learning is also greatly improved,and the students’English proficiency can be improved.
基金supported by the Integrated Rail Transit Dispatch Control and Intermodal Transport Service Technology Project(Grant No.2022YFB4300500).
文摘The Balise Transmission Module(BTM)unit of the on-board train control system is a crucial component.Due to its unique installation position and complex environment,this unit has a higher fault rate within the on-board train control system.To conduct fault prediction for the BTM unit based on actual fault data,this study proposes a prediction method combining reliability statistics and machine learning,and achieves the fusion of prediction results from different dimensions through multi-method interactive validation.Firstly,a method for predicting equipment fault time targeting batch equipment is introduced.This method utilizes reliability statistics to construct a model of the remaining faultless operating time distribution considering uncertainty,thereby predicting the remaining faultless operating probability of the BTM unit.Secondly,considering the complexity of the BTM unit’s fault mechanism,the small sample size of fault cases,and the potential presence of multiple fault features in fault text records,an individual-oriented fault prediction method based on Bayesian-optimized Gradient Boosting Regression Tree(Bayes-GBRT)is proposed.This method achieves better prediction results compared to linear regression algorithms and random forest regression algorithms,with an average absolute error of only 0.224 years for predicting the fault time of this type of equipment.Finally,a multi-method interactive validation approach is proposed,enabling the fusion and validation of multi-dimensional results.The results indicate that the predicted fault time and the actual fault time conform to a log-normal distribution,and the parameter estimation results are basically consistent,verifying the accuracy and effectiveness of the prediction results.The above research findings can provide technical support for the maintenance and modification of BTM units,effectively reducing maintenance costs and ensuring the safe operation of high-speed railway,thus having practical engineering value for preventive maintenance.
文摘In the stage of senior high school education, senior high school Chinese is an important basic subject. There are various teaching methods in Chinese teaching in senior high schools, and interactive teaching method is a common teaching method. Through good interaction between teachers and students, an efficient Chinese classroom can be constructed. Students can learn and master more Chinese knowledge in the limited classroom learning time. At the same time, the Chinese interactive teaching method can also expand the students thinking of language and literature study, so that students can be inspired and educated through the interactive communication between teachers and students and between students. It is beneficial for students to study Chinese more deeply and comprehensively and further improve their Chinese learning level.
文摘At present,in the high school English classroom teaching,there are still some problems,which is an obstacle to hinder the smooth development of English teaching,in this case,in order to improve the efficiency of the high school English teaching,the use of this method has been used which can largely improve the students’interest in learning,to build interesting class.This paper analyzes the application of interactive teaching method in English classroom teaching for reference.
基金National Natural Science Foundation of China under Grant No.51478247National Key Research and Development Program of China under Grant No.2016YFC1402800
文摘The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident wave into equivalent loads on the cutoff boundaries. The wave method has high precision, but the implementation is complicated, especially for three-dimensional models. By deducing another form of equivalent input seismic loads in the fi nite element model, a new seismic wave input method is proposed. In the new method, by imposing the displacements of the free wave fi eld on the nodes of the substructure composed of elements that contain artifi cial boundaries, the equivalent input seismic loads are obtained through dynamic analysis of the substructure. Subsequently, the equivalent input seismic loads are imposed on the artifi cial boundary nodes to complete the seismic wave input and perform seismic analysis of the soil-structure dynamic interaction model. Compared with the wave method, the new method is simplifi ed by avoiding the complex processes of calculating the equivalent input seismic loads. The validity of the new method is verifi ed by the dynamic analysis numerical examples of the homogeneous and layered half space under vertical and oblique incident seismic waves.
基金supported jointlyby the Chinese Academy of Sciences under Grant KZCX2-YW-220the National Basic Research Program of Chinaunder Grant 2009CB421405the National Natural Sci-ence Foundation of China under Grant No.40730952
文摘To improve the land surface simulation in the arid and semi-arid areas of northern China, the observational data from two field experiments in Dunhuang and Tongyu are used to optimize the parameters in the land surface model, BATS, through calibration with the multicriteria method. Sensitivity analysis to the parameters in Dunhuang and Tongyu indicates that different parameters need to be calibrated in two sites with different environmental and climate regimes. Comparison of observed sensible heat flux, latent heat flux, and ground surface temperature with the simulated ones shows the simulations with the optimized parameters have been substantially improved. Especially, the holistic simulations with the calibration of the parameter values are much closer to the observations in the arid region (Dunhuang), and the energy partition with the calibrated parameters can also be simulated well in the semi-arid region (Tongyu). Whole results demonstrate that the parameter calibration of the land surface model is important when the model is to be used to investigate the land-air interaction.
文摘Fluid-structure interaction (FSI) is essentially a dynamic phenomenon and always exists in fluid-filled pipe system. The four-equation model, which has been proved to be effective to describe and predict the phenomenon of FSI due to friction coupling and Poisson coupling being taken into account, is utilized to describe the FSI of fluid-filled pipe system. Terse compatibility equations are educed by the method of characteristics (MOC) to describe the fluid-filled pipe system. To shorten computing time needed to get the solutions under the condition of keeping accuracy requirement, two steps are adopted, firstly the time step Δt and divided number of the straight pipe are optimized, sec-ondly the mesh spacing Δz close to boundary is subdivided in several submeshes automatically ac-cording to the speed gradient of fluid. The mathematical model and arithmetic are validated by com-parisons between simulation solutions of two straight pipe systems and experiment known from lit-erature.
文摘In this study, an advanced Lagrangian vortex- boundary element method is applied to simulate the unsteady impeller-diffuser interactions in a diffuser pump not only for design but also for off-design considerations. In velocity calculations based on the Biot-Savart law we do not have to grid large portions of the flow field and the calculation points are concentrated in the regions where vorticity is present. Lagrangian representation of the evolving vorticity field is well suited to moving boundaries. An integral pressure equation shows that the pressure distribution can be estimated directly from the instantaneous velocity and vorticity field. The numerical results are compared with the experimental data and the comparisons show that the method used in this study can provide us insight into the complicated unsteady impeller-diffuser interaction phenomena in a diffuser pump.
基金Project supported by the National Natural Science Foundation of China (No.10172038)
文摘Based on the transfer matrix method and the virtual source simulation technique, this paper proposes a novel semi-analytical and semi-numerical method for solving 2-D sound- structure interaction problems under a harmonic excitation.Within any integration segment, as long as its length is small enough,along the circumferential curvilinear coordinate,the non- homogeneous matrix differential equation of an elastic ring of complex geometrical shape can be rewritten in terms of the homogeneous one by the method of extended homogeneous capacity proposed in this paper.For the exterior fluid domain,the multi-circular virtual source simulation technique is adopted.The source density distributed on each virtual circular curve may be ex- panded as the Fourier's series.Combining with the inverse fast Fourier transformation,a higher accuracy and efficiency method for solving 2-D exterior Helmholtz's problems is presented in this paper.In the aspect of solution to the coupling equations,the state vectors of elastic ring induced by the given harmonic excitation and generalized forces of coefficients of the Fourier series can be obtained respectively by using a high precision integration scheme combined with the method of extended homogeneous capacity put forward in this paper.According to the superposition princi- ple and compatibility conditions at the interface between the elastic ring and fluid,the algebraic equation of system can be directly constructed by using the least square approximation.Examples of acoustic radiation from two typical fluid-loaded elastic rings under a harmonic concentrated force are presented.Numerical results show that the method proposed is more efficient than the mixed FE-BE method in common use.
基金the State Key Program of National Natural Science of China under Grant No.51138001Science Fund for Creative Research Groups of the National Natural Science Foundation of China under Grant No.51121005Open Research Fund Program of State key Laboratory of Hydro science and Engineering under Grant No.shlhse-2010-C-03
文摘Consideration of structure-foundation-soil dynamic interaction is a basic requirement in the evaluation of the seismic safety of nuclear power facilities. An efficient and accurate dynamic interaction numerical model in the time domain has become an important topic of current research. In this study, the scaled boundary finite element method (SBFEM) is improved for use as an effective numerical approach with good application prospects. This method has several advantages, including dimensionality reduction, accuracy of the radial analytical solution, and unlike other boundary element methods, it does not require a fundamental solution. This study focuses on establishing a high performance scaled boundary finite element interaction analysis model in the time domain based on the acceleration unit-impulse response matrix, in which several new solution techniques, such as a dimensionless method to solve the interaction force, are applied to improve the numerical stability of the actual soil parameters and reduce the amount of calculation. Finally, the feasibility of the time domain methods are illustrated by the response of the nuclear power structure and the accuracy of the algorithms are dynamically verified by comparison with the refinement of a large-scale viscoelastic soil model.
基金Supported by the National Natural Science Foundation of China(51379125,51490675,11432009,51579145)Chang Jiang Scholars Program(T2014099)+3 种基金Shanghai Excellent Academic Leaders Program(17XD1402300)Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(2013022)Innovative Special Project of Numerical Tank of the Ministry of Industry and Information Technology of China(2016-23/09)Lloyd’s Register Foundation for Doctoral Students
文摘Fluid-Structure Interaction(FSI) caused by fluid impacting onto a flexible structure commonly occurs in naval architecture and ocean engineering. Research on the problem of wave-structure interaction is important to ensure the safety of offshore structures. This paper presents the Moving Particle Semi-implicit and Finite Element Coupled Method(MPS-FEM) to simulate FSI problems. The Moving Particle Semi-implicit(MPS) method is used to calculate the fluid domain, while the Finite Element Method(FEM) is used to address the structure domain. The scheme for the coupling of MPS and FEM is introduced first. Then, numerical validation and convergent study are performed to verify the accuracy of the solver for solitary wave generation and FSI problems. The interaction between the solitary wave and an elastic structure is investigated by using the MPS-FEM coupled method.