The global nuclear mass based on the macroscopic-microscopic model was studied by applying a newly designed multi-task learning artificial neural network(MTL-ANN). First, the reported nuclear binding energies of 2095 ...The global nuclear mass based on the macroscopic-microscopic model was studied by applying a newly designed multi-task learning artificial neural network(MTL-ANN). First, the reported nuclear binding energies of 2095 nuclei(Z ≥ 8, N ≥ 8) released in the latest Atomic Mass Evaluation AME2020 and the deviations between the fitting result of the liquid drop model(LDM)and data from AME2020 for each nucleus were obtained.To compensate for the deviations and investigate the possible ignored physics in the LDM, the MTL-ANN method was introduced in the model. Compared to the single-task learning(STL) method, this new network has a powerful ability to simultaneously learn multi-nuclear properties,such as the binding energies and single neutron and proton separation energies. Moreover, it is highly effective in reducing the risk of overfitting and achieving better predictions. Consequently, good predictions can be obtained using this nuclear mass model for both the training and validation datasets and for the testing dataset. In detail, the global root mean square(RMS) of the binding energy is effectively reduced from approximately 2.4 MeV of LDM to the current 0.2 MeV, and the RMS of Sn, Spcan also reach approximately 0.2 MeV. Moreover, compared to STL, for the training and validation sets, 3-9% improvement can be achieved with the binding energy, and 20-30% improvement for S_(n), S_(p);for the testing sets, the reduction in deviations can even reach 30-40%, which significantly illustrates the advantage of the current MTL.展开更多
In this paper,we summarize recent progresses made in deep learning based acoustic models and the motivation and insights behind the surveyed techniques.We first discuss models such as recurrent neural networks(RNNs) a...In this paper,we summarize recent progresses made in deep learning based acoustic models and the motivation and insights behind the surveyed techniques.We first discuss models such as recurrent neural networks(RNNs) and convolutional neural networks(CNNs) that can effectively exploit variablelength contextual information,and their various combination with other models.We then describe models that are optimized end-to-end and emphasize on feature representations learned jointly with the rest of the system,the connectionist temporal classification(CTC) criterion,and the attention-based sequenceto-sequence translation model.We further illustrate robustness issues in speech recognition systems,and discuss acoustic model adaptation,speech enhancement and separation,and robust training strategies.We also cover modeling techniques that lead to more efficient decoding and discuss possible future directions in acoustic model research.展开更多
The ongoing effort to create methods for detecting and quantifying fatigue damage is motivated by the high levels of uncertainty in present fatigue-life prediction approaches and the frequently catastrophic nature of ...The ongoing effort to create methods for detecting and quantifying fatigue damage is motivated by the high levels of uncertainty in present fatigue-life prediction approaches and the frequently catastrophic nature of fatigue failure.The fatigue life of high strength aluminum alloy 2090-T83 is predicted in this study using a variety of artificial intelligence and machine learning techniques for constant amplitude and negative stress ratios(R?1).Artificial neural networks(ANN),adaptive neuro-fuzzy inference systems(ANFIS),support-vector machines(SVM),a random forest model(RF),and an extreme-gradient tree-boosting model(XGB)are trained using numerical and experimental input data obtained from fatigue tests based on a relatively low number of stress measurements.In particular,the coefficients of the traditional force law formula are found using relevant numerical methods.It is shown that,in comparison to traditional approaches,the neural network and neuro-fuzzy models produce better results,with the neural network models trained using the boosting iterations technique providing the best performances.Building strong models from weak models,XGB helps to predict fatigue life by reducing model partiality and variation in supervised learning.Fuzzy neural models can be used to predict the fatigue life of alloys more accurately than neural networks and traditional methods.展开更多
Multi-scale problems in Computational Fluid Dynamics(CFD)often require numerous simulations across various design parameters.Using a fixed mesh for all cases may fail to capture critical physical features.Moving mesh ...Multi-scale problems in Computational Fluid Dynamics(CFD)often require numerous simulations across various design parameters.Using a fixed mesh for all cases may fail to capture critical physical features.Moving mesh adaptation provides an optimal resource allocation to obtain high-resolution flow-fields on low-resolution meshes.However,most existing methods require manual experience and the flow posteriori information poses great challenges to practical applications.In addition,generating adaptive meshes directly from design parameters is difficult due to highly nonlinear relationships.The diffusion model is currently the most popular model in generative tasks that integrates the diffusion principle into deep learning to capture the complex nonlinear correlations.A dual diffusion framework,Para2Mesh,is proposed to predict the adaptive meshes from design parameters by exploiting the robust data distribution learning ability of the diffusion model.Through iterative denoising,the proposed dual networks accurately reconstruct the flow-field to provide flow features as supervised information,and then achieve rapid and reliable mesh movement.Experiments in CFD scenarios demonstrate that Para2Mesh predicts similar meshes directly from design parameters with much higher efficiency than traditional method.It could become a real-time adaptation tool to assist engineering design and optimization,providing a promising solution for high-resolution flow-field analysis.展开更多
Tibetan Jiu chess,recognized as a national intangible cultural heritage,is a complex game comprising two distinct phases:the layout phase and the battle phase.Improving the performance of deep reinforcement learning(D...Tibetan Jiu chess,recognized as a national intangible cultural heritage,is a complex game comprising two distinct phases:the layout phase and the battle phase.Improving the performance of deep reinforcement learning(DRL)models for Tibetan Jiu chess is challenging,especially given the constraints of hardware resources.To address this,we propose a two-stage model called JFA,which incorporates hierarchical neural networks and knowledge-guided techniques.The model includes sub-models:strategic layout model(SLM)for the layout phase and hierarchical battle model(HBM)for the battle phase.Both sub-models use similar network structures and employ parallel Monte Carlo tree search(MCTS)methods for independent self-play training.HBM is structured as a hierarchical neural network,with the upper network selecting movement and jump capturing actions and the lower network handling square capturing actions.Human knowledge-based auxiliary agents are introduced to assist SLM and HBM,simulating the entire game and providing reward signals based on square capturing or victory outcomes.Additionally,within the HBM,we propose two human knowledge-based pruning methods that prune parallel MCTS and capture actions in the lower network.In the experiments against a layout model using the AlphaZero method,SLM achieves a 74%win rate,with the decision-making time being reduced to approximately 1/147 of the time required by the AlphaZero model.SLM also won the first place at the 2024 China National Computer Game Tournament.HBM achieves a 70%win rate when playing against other Tibetan Jiu chess models.When used together,SLM and HBM in JFA achieve an 81%win rate,comparable to the level of a human amateur 4-dan player.These results demonstrate that JFA effectively enhances artificial intelligence(AI)performance in Tibetan Jiu chess.展开更多
Management of the electrical grid is becoming more complex due to the increased penetration of alternative energy generation technologies and a broadening diversity of electric loads.This complexity creates challenges...Management of the electrical grid is becoming more complex due to the increased penetration of alternative energy generation technologies and a broadening diversity of electric loads.This complexity creates challenges in balancing demand and generation that can increase the potential for grid instabilities.One effective way to address this issue is to leverage previously unexploited demand flexibility through advanced control strategies.In this work,we propose an advanced control method,called adaptive neural parameter-varying model predictive control(ANPV-MPC),to control the temperature and energy consumption of a building via its Heating,Ventilation,and Air Conditioning system.ANPV-MPC combines key ideas in varying parameter-control,adaptive control,and online learning strategies to bridge the gap between computationally efficient linear model predictive control and more accurate nonlinear model predictive control.The novelty in ANPV-MPC is the use of a physics-inspired Bayesian neural network to estimate the coefficients of the parameter-varying linear control model.The Bayesian neural network additionally provides uncertainty estimates,triggering online training to capture evolving building system conditions.We show that ANPV-MPC can approximate the building system dynamics with a 28.39%higher accuracy than traditional linear model predictive control,resulting in 36.23%better control performance without increasing complexity of the optimal control problem.ANPV-MPC also adapts in real time to previously unseen conditions using online learning,further improving its performance.展开更多
基金supported by the National Natural Science Foundation of China(Nos.1187050492,12005303,and 12175170).
文摘The global nuclear mass based on the macroscopic-microscopic model was studied by applying a newly designed multi-task learning artificial neural network(MTL-ANN). First, the reported nuclear binding energies of 2095 nuclei(Z ≥ 8, N ≥ 8) released in the latest Atomic Mass Evaluation AME2020 and the deviations between the fitting result of the liquid drop model(LDM)and data from AME2020 for each nucleus were obtained.To compensate for the deviations and investigate the possible ignored physics in the LDM, the MTL-ANN method was introduced in the model. Compared to the single-task learning(STL) method, this new network has a powerful ability to simultaneously learn multi-nuclear properties,such as the binding energies and single neutron and proton separation energies. Moreover, it is highly effective in reducing the risk of overfitting and achieving better predictions. Consequently, good predictions can be obtained using this nuclear mass model for both the training and validation datasets and for the testing dataset. In detail, the global root mean square(RMS) of the binding energy is effectively reduced from approximately 2.4 MeV of LDM to the current 0.2 MeV, and the RMS of Sn, Spcan also reach approximately 0.2 MeV. Moreover, compared to STL, for the training and validation sets, 3-9% improvement can be achieved with the binding energy, and 20-30% improvement for S_(n), S_(p);for the testing sets, the reduction in deviations can even reach 30-40%, which significantly illustrates the advantage of the current MTL.
文摘In this paper,we summarize recent progresses made in deep learning based acoustic models and the motivation and insights behind the surveyed techniques.We first discuss models such as recurrent neural networks(RNNs) and convolutional neural networks(CNNs) that can effectively exploit variablelength contextual information,and their various combination with other models.We then describe models that are optimized end-to-end and emphasize on feature representations learned jointly with the rest of the system,the connectionist temporal classification(CTC) criterion,and the attention-based sequenceto-sequence translation model.We further illustrate robustness issues in speech recognition systems,and discuss acoustic model adaptation,speech enhancement and separation,and robust training strategies.We also cover modeling techniques that lead to more efficient decoding and discuss possible future directions in acoustic model research.
文摘The ongoing effort to create methods for detecting and quantifying fatigue damage is motivated by the high levels of uncertainty in present fatigue-life prediction approaches and the frequently catastrophic nature of fatigue failure.The fatigue life of high strength aluminum alloy 2090-T83 is predicted in this study using a variety of artificial intelligence and machine learning techniques for constant amplitude and negative stress ratios(R?1).Artificial neural networks(ANN),adaptive neuro-fuzzy inference systems(ANFIS),support-vector machines(SVM),a random forest model(RF),and an extreme-gradient tree-boosting model(XGB)are trained using numerical and experimental input data obtained from fatigue tests based on a relatively low number of stress measurements.In particular,the coefficients of the traditional force law formula are found using relevant numerical methods.It is shown that,in comparison to traditional approaches,the neural network and neuro-fuzzy models produce better results,with the neural network models trained using the boosting iterations technique providing the best performances.Building strong models from weak models,XGB helps to predict fatigue life by reducing model partiality and variation in supervised learning.Fuzzy neural models can be used to predict the fatigue life of alloys more accurately than neural networks and traditional methods.
基金co-supported by the Aeronautical Science Foundation of China(Nos.2018ZA52002 and 2019ZA052011)。
文摘Multi-scale problems in Computational Fluid Dynamics(CFD)often require numerous simulations across various design parameters.Using a fixed mesh for all cases may fail to capture critical physical features.Moving mesh adaptation provides an optimal resource allocation to obtain high-resolution flow-fields on low-resolution meshes.However,most existing methods require manual experience and the flow posteriori information poses great challenges to practical applications.In addition,generating adaptive meshes directly from design parameters is difficult due to highly nonlinear relationships.The diffusion model is currently the most popular model in generative tasks that integrates the diffusion principle into deep learning to capture the complex nonlinear correlations.A dual diffusion framework,Para2Mesh,is proposed to predict the adaptive meshes from design parameters by exploiting the robust data distribution learning ability of the diffusion model.Through iterative denoising,the proposed dual networks accurately reconstruct the flow-field to provide flow features as supervised information,and then achieve rapid and reliable mesh movement.Experiments in CFD scenarios demonstrate that Para2Mesh predicts similar meshes directly from design parameters with much higher efficiency than traditional method.It could become a real-time adaptation tool to assist engineering design and optimization,providing a promising solution for high-resolution flow-field analysis.
基金supported by the National Natural Science Foundation of China(Nos.62276285 and 62236011)。
文摘Tibetan Jiu chess,recognized as a national intangible cultural heritage,is a complex game comprising two distinct phases:the layout phase and the battle phase.Improving the performance of deep reinforcement learning(DRL)models for Tibetan Jiu chess is challenging,especially given the constraints of hardware resources.To address this,we propose a two-stage model called JFA,which incorporates hierarchical neural networks and knowledge-guided techniques.The model includes sub-models:strategic layout model(SLM)for the layout phase and hierarchical battle model(HBM)for the battle phase.Both sub-models use similar network structures and employ parallel Monte Carlo tree search(MCTS)methods for independent self-play training.HBM is structured as a hierarchical neural network,with the upper network selecting movement and jump capturing actions and the lower network handling square capturing actions.Human knowledge-based auxiliary agents are introduced to assist SLM and HBM,simulating the entire game and providing reward signals based on square capturing or victory outcomes.Additionally,within the HBM,we propose two human knowledge-based pruning methods that prune parallel MCTS and capture actions in the lower network.In the experiments against a layout model using the AlphaZero method,SLM achieves a 74%win rate,with the decision-making time being reduced to approximately 1/147 of the time required by the AlphaZero model.SLM also won the first place at the 2024 China National Computer Game Tournament.HBM achieves a 70%win rate when playing against other Tibetan Jiu chess models.When used together,SLM and HBM in JFA achieve an 81%win rate,comparable to the level of a human amateur 4-dan player.These results demonstrate that JFA effectively enhances artificial intelligence(AI)performance in Tibetan Jiu chess.
基金supported by the Laboratory Directed Research and Development(LDRD)Program at NREL.
文摘Management of the electrical grid is becoming more complex due to the increased penetration of alternative energy generation technologies and a broadening diversity of electric loads.This complexity creates challenges in balancing demand and generation that can increase the potential for grid instabilities.One effective way to address this issue is to leverage previously unexploited demand flexibility through advanced control strategies.In this work,we propose an advanced control method,called adaptive neural parameter-varying model predictive control(ANPV-MPC),to control the temperature and energy consumption of a building via its Heating,Ventilation,and Air Conditioning system.ANPV-MPC combines key ideas in varying parameter-control,adaptive control,and online learning strategies to bridge the gap between computationally efficient linear model predictive control and more accurate nonlinear model predictive control.The novelty in ANPV-MPC is the use of a physics-inspired Bayesian neural network to estimate the coefficients of the parameter-varying linear control model.The Bayesian neural network additionally provides uncertainty estimates,triggering online training to capture evolving building system conditions.We show that ANPV-MPC can approximate the building system dynamics with a 28.39%higher accuracy than traditional linear model predictive control,resulting in 36.23%better control performance without increasing complexity of the optimal control problem.ANPV-MPC also adapts in real time to previously unseen conditions using online learning,further improving its performance.