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A Deep Learning Approach to Shape Optimization Problems for Flexoelectric Materials Using the Isogeometric Finite Element Method
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作者 Yu Cheng Yajun Huang +3 位作者 Shuai Li Zhongbin Zhou Xiaohui Yuan Yanming Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1935-1960,共26页
A new approach for flexoelectricmaterial shape optimization is proposed in this study.In this work,a proxymodel based on artificial neural network(ANN)is used to solve the parameter optimization and shape optimization... A new approach for flexoelectricmaterial shape optimization is proposed in this study.In this work,a proxymodel based on artificial neural network(ANN)is used to solve the parameter optimization and shape optimization problems.To improve the fitting ability of the neural network,we use the idea of pre-training to determine the structure of the neural network and combine different optimizers for training.The isogeometric analysis-finite element method(IGA-FEM)is used to discretize the flexural theoretical formulas and obtain samples,which helps ANN to build a proxy model from the model shape to the target value.The effectiveness of the proposed method is verified through two numerical examples of parameter optimization and one numerical example of shape optimization. 展开更多
关键词 Shape optimization deep learning flexoelectric structure finite element method isogeometric
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The Effectiveness of Group Cooperative Learning Method in Badminton Teaching in Colleges and Universities
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作者 Jiankun Feng 《Journal of Contemporary Educational Research》 2024年第4期290-295,共6页
In college badminton teaching,teachers utilize the group cooperative learning method,which not only helps to improve students’badminton skill level but also cultivates their teamwork spirit,communication skills,and s... In college badminton teaching,teachers utilize the group cooperative learning method,which not only helps to improve students’badminton skill level but also cultivates their teamwork spirit,communication skills,and self-management ability unconsciously.In view of this,this paper mainly describes the significance of applying the group cooperative learning method in college badminton teaching,analyzes the current problems in college badminton teaching,and aims to discover effective development strategies for group cooperative learning method in college badminton teaching in order to improve the effectiveness of college badminton teaching. 展开更多
关键词 Group cooperative learning method Colleges and universities Badminton teaching Effective development
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Design of N-11-Azaartemisinins Potentially Active against Plasmodium falciparum by Combined Molecular Electrostatic Potential, Ligand-Receptor Interaction and Models Built with Supervised Machine Learning Methods
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作者 Jeferson Stiver Oliveira de Castro José Ciríaco Pinheiro +5 位作者 Sílvia Simone dos Santos de Morais Heriberto Rodrigues Bitencourt Antonio Florêncio de Figueiredo Marcos Antonio Barros dos Santos Fábio dos Santos Gil Ana Cecília Barbosa Pinheiro 《Journal of Biophysical Chemistry》 CAS 2023年第1期1-29,共29页
N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning m... N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning methods (PCA, HCA, KNN, SIMCA, and SDA). The optimization of molecular structures was performed using the B3LYP/6-31G* approach. MEP maps and ligand-receptor interactions were used to investigate key structural features required for biological activities and likely interactions between N-11-azaartemisinins and heme, respectively. The supervised machine learning methods allowed the separation of the investigated compounds into two classes: cha and cla, with the properties ε<sub>LUMO+1</sub> (one level above lowest unoccupied molecular orbital energy), d(C<sub>6</sub>-C<sub>5</sub>) (distance between C<sub>6</sub> and C<sub>5</sub> atoms in ligands), and TSA (total surface area) responsible for the classification. The insights extracted from the investigation developed and the chemical intuition enabled the design of sixteen new N-11-azaartemisinins (prediction set), moreover, models built with supervised machine learning methods were applied to this prediction set. The result of this application showed twelve new promising N-11-azaartemisinins for synthesis and biological evaluation. 展开更多
关键词 Antimalarial Design MEP Ligand-Receptor Interaction Supervised Machine learning methods Models Built with Supervised Machine learning methods
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A Real-time Prediction System for Molecular-level Information of Heavy Oil Based on Machine Learning
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作者 Yuan Zhuang Wang Yuan +8 位作者 Zhang Zhibo Yuan Yibo Yang Zhe Xu Wei Lin Yang Yan Hao Zhou Xin Zhao Hui Yang Chaohe 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期121-134,共14页
Acquiring accurate molecular-level information about petroleum is crucial for refining and chemical enterprises to implement the“selection of the optimal processing route”strategy.With the development of data predic... Acquiring accurate molecular-level information about petroleum is crucial for refining and chemical enterprises to implement the“selection of the optimal processing route”strategy.With the development of data prediction systems represented by machine learning,it has become possible for real-time prediction systems of petroleum fraction molecular information to replace analyses such as gas chromatography and mass spectrometry.However,the biggest difficulty lies in acquiring the data required for training the neural network.To address these issues,this work proposes an innovative method that utilizes the Aspen HYSYS and full two-dimensional gas chromatography-time-of-flight mass spectrometry to establish a comprehensive training database.Subsequently,a deep neural network prediction model is developed for heavy distillate oil to predict its composition in terms of molecular structure.After training,the model accurately predicts the molecular composition of catalytically cracked raw oil in a refinery.The validation and test sets exhibit R2 values of 0.99769 and 0.99807,respectively,and the average relative error of molecular composition prediction for raw materials of the catalytic cracking unit is less than 7%.Finally,the SHAP(SHapley Additive ExPlanation)interpretation method is used to disclose the relationship among different variables by performing global and local weight comparisons and correlation analyses. 展开更多
关键词 heavy distillate oil molecular composition deep learning SHAP interpretation method
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Toward Improved Accuracy in Quasi-Static Elastography Using Deep Learning
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作者 Yue Mei Jianwei Deng +4 位作者 Dongmei Zhao Changjiang Xiao Tianhang Wang Li Dong Xuefeng Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期911-935,共25页
Elastography is a non-invasive medical imaging technique to map the spatial variation of elastic properties of soft tissues.The quality of reconstruction results in elastography is highly sensitive to the noise induce... Elastography is a non-invasive medical imaging technique to map the spatial variation of elastic properties of soft tissues.The quality of reconstruction results in elastography is highly sensitive to the noise induced by imaging measurements and processing.To address this issue,we propose a deep learning(DL)model based on conditional Generative Adversarial Networks(cGANs)to improve the quality of nonhomogeneous shear modulus reconstruction.To train this model,we generated a synthetic displacement field with finite element simulation under known nonhomogeneous shear modulus distribution.Both the simulated and experimental displacement fields are used to validate the proposed method.The reconstructed results demonstrate that the DL model with synthetic training data is able to improve the quality of the reconstruction compared with the well-established optimization method.Moreover,we emphasize that our DL model is only trained on synthetic data.This might provide a way to alleviate the challenge of obtaining clinical or experimental data in elastography.Overall,this work addresses several fatal issues in applying the DL technique into elastography,and the proposed method has shown great potential in improving the accuracy of the disease diagnosis in clinical medicine. 展开更多
关键词 Nonhomogeneous elastic property distribution reconstruction deep learning finite element method inverse problem ELASTOGRAPHY conditional generative adversarial network
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A systematic machine learning method for reservoir identification and production prediction 被引量:1
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作者 Wei Liu Zhangxin Chen +1 位作者 Yuan Hu Liuyang Xu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期295-308,共14页
Reservoir identification and production prediction are two of the most important tasks in petroleum exploration and development.Machine learning(ML)methods are used for petroleum-related studies,but have not been appl... Reservoir identification and production prediction are two of the most important tasks in petroleum exploration and development.Machine learning(ML)methods are used for petroleum-related studies,but have not been applied to reservoir identification and production prediction based on reservoir identification.Production forecasting studies are typically based on overall reservoir thickness and lack accuracy when reservoirs contain a water or dry layer without oil production.In this paper,a systematic ML method was developed using classification models for reservoir identification,and regression models for production prediction.The production models are based on the reservoir identification results.To realize the reservoir identification,seven optimized ML methods were used:four typical single ML methods and three ensemble ML methods.These methods classify the reservoir into five types of layers:water,dry and three levels of oil(I oil layer,II oil layer,III oil layer).The validation and test results of these seven optimized ML methods suggest the three ensemble methods perform better than the four single ML methods in reservoir identification.The XGBoost produced the model with the highest accuracy;up to 99%.The effective thickness of I and II oil layers determined during the reservoir identification was fed into the models for predicting production.Effective thickness considers the distribution of the water and the oil resulting in a more reasonable production prediction compared to predictions based on the overall reservoir thickness.To validate the superiority of the ML methods,reference models using overall reservoir thickness were built for comparison.The models based on effective thickness outperformed the reference models in every evaluation metric.The prediction accuracy of the ML models using effective thickness were 10%higher than that of reference model.Without the personal error or data distortion existing in traditional methods,this novel system realizes rapid analysis of data while reducing the time required to resolve reservoir classification and production prediction challenges.The ML models using the effective thickness obtained from reservoir identification were more accurate when predicting oil production compared to previous studies which use overall reservoir thickness. 展开更多
关键词 Reservoir identification Production prediction Machine learning Ensemble method
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A new optimal adaptive backstepping control approach for nonlinear systems under deception attacks via reinforcement learning
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作者 Wendi Chen Qinglai Wei 《Journal of Automation and Intelligence》 2024年第1期34-39,共6页
In this paper,a new optimal adaptive backstepping control approach for nonlinear systems under deception attacks via reinforcement learning is presented in this paper.The existence of nonlinear terms in the studied sy... In this paper,a new optimal adaptive backstepping control approach for nonlinear systems under deception attacks via reinforcement learning is presented in this paper.The existence of nonlinear terms in the studied system makes it very difficult to design the optimal controller using traditional methods.To achieve optimal control,RL algorithm based on critic–actor architecture is considered for the nonlinear system.Due to the significant security risks of network transmission,the system is vulnerable to deception attacks,which can make all the system state unavailable.By using the attacked states to design coordinate transformation,the harm brought by unknown deception attacks has been overcome.The presented control strategy can ensure that all signals in the closed-loop system are semi-globally ultimately bounded.Finally,the simulation experiment is shown to prove the effectiveness of the strategy. 展开更多
关键词 Nonlinear systems Reinforcement learning Optimal control Backstepping method
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Exploring the Application Effect of Flipped Classroom Combined with Problem-Based Learning Teaching Method in Clinical Skills Teaching of Standardized Training for Resident Doctors of Traditional Chinese Medicine 被引量:1
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作者 Jingjing Tang 《Journal of Biosciences and Medicines》 CAS 2023年第2期169-176,共8页
Objective: To explore the application effect of flipped classroom combined with problem-based learning teaching method in clinical skills teaching of standardized training for resident doctors of traditional Chinese M... Objective: To explore the application effect of flipped classroom combined with problem-based learning teaching method in clinical skills teaching of standardized training for resident doctors of traditional Chinese Medicine. Methods: The study used the experimental control method. The study lasted from September to November 2022. The subjects of this study were 49 students of standardized training for resident doctors of traditional Chinese Medicine from grades 2020, 2021 and 2022 of Dazhou integrated TCM & Western Medicine Hospital. They were randomly divided into experiment group (25) and control group (24). The experiment group adopted flipped classroom combined with problem-based learning teaching method, and the control group adopted traditional teaching method. The teaching content was 4 basic clinical skill projects, including four diagnoses of traditional Chinese Medicine, cardiopulmonary resuscitation, dressing change procedure, acupuncture and massage. The evaluation method was carried out by comparing the students’ performance and a self-designed questionnaire was used to investigate the students’ evaluation of the teaching method. Results: The test scores of total scores in the experimental group (90.12 ± 5.89) were all higher than those in the control group (81.47 ± 7.96) (t = 4.53, P P Conclusions: The teaching process of the flipped classroom combined with problem-based learning teaching method is conducive to improving the efficiency of classroom teaching, cultivating students’ self-learning ability, and enhancing students’ willingness to learn. 展开更多
关键词 Standardized Training for Resident Doctors of Traditional Chinese Medicine Clinical Skills Teaching Flipped Classroom Problem-Based learning Teaching method
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Constitutive modelling of idealised granular materials using machine learning method 被引量:1
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作者 Mengmeng Wu Zhangqi Xia Jianfeng Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期1038-1051,共14页
Predicting the constitutive response of granular soils is a fundamental goal in geomechanics.This paper presents a machine learning(ML)framework for the prediction of the stress-strain behaviour and shearinduced conta... Predicting the constitutive response of granular soils is a fundamental goal in geomechanics.This paper presents a machine learning(ML)framework for the prediction of the stress-strain behaviour and shearinduced contact fabric evolution of an idealised granular material subject to triaxial shearing.The MLbased framework is comprised of a set of mini-triaxial tests which provide a benchmark for the setup and validation of the discrete element method(DEM)model of the granular materials,a parametric DEM simulation programme of virtual triaxial tests which provides datasets of micro-and macro-mechanical information,as well as a multi-layer perceptron(MLP)neural network which is trained and tested using the DEM-based datasets.The ML model only requires the initial void ratio of the granular sample as the input for predicting its constitutive response.The excellent agreement between the ML model prediction and experimental test and DEM simulation results indicates that the MLebased modelling approach is capable of capturing accurately the effects of initial void ratio on the constitutive behaviour of idealised granular materials,bypassing the need to incorporate the complex micromechanics underlying the macroscopic mechanical behaviour of granular materials.Lastly,a detailed comparison between the used MLP model and long short-term memory(LSTM)model was made from the perspective of technical algorithm,prediction accuracy,and computational efficiency. 展开更多
关键词 Machine learning(ML) Multi-layer perceptron(MLP) Contact fabric Granular material Discrete element method(DEM)
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Research and Discussion on Flipped Classroom Combined with Case-Based Learning in Pharmacoeconomics Teaching
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作者 Xingwen Zhou Zilong Dang +4 位作者 Xingdong Wang Chen Chen Zhi Rao Ting Wei Yanping Wang 《Journal of Contemporary Educational Research》 2024年第4期120-125,共6页
Objective:To explore the application effect of flipped classroom combined with case-based learning teaching methods in pharmacoeconomics teaching.Methods:The students majoring in clinical pharmacy in 2019 were selecte... Objective:To explore the application effect of flipped classroom combined with case-based learning teaching methods in pharmacoeconomics teaching.Methods:The students majoring in clinical pharmacy in 2019 were selected as the study subjects,and the cost-effectiveness analysis of different dosage forms of Yinzhihuang in the treatment of neonatal jaundice was selected as the teaching case.The flipped classroom combined with case-based learning teaching method was used to carry out theoretical teaching to the students.After the course,questionnaires were distributed through the Sojump platform to evaluate the teaching effect.Results:The results of the questionnaire showed that 85.71%of the students believed that the flipped classroom combined with case-based learning teaching method was helpful in mobilizing the learning enthusiasm and initiative,and improving the comprehensive application ability of the knowledge of pharmacoeconomics.92.86%of the students think that it is conducive to the understanding and memorization of learning content,as well as the cultivation of teamwork,communication,etc.Conclusion:Flipped classroom combined with case-based learning teaching method can improve students’knowledge mastery,thinking skills,and practical application skills,as well as optimize and improve teachers’teaching levels. 展开更多
关键词 Flipped classroom Case-based learning teaching method PHARMACOECONOMICS Teaching methods
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基于改进Q-learning算法的移动机器人路径规划
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作者 井征淼 刘宏杰 周永录 《火力与指挥控制》 CSCD 北大核心 2024年第3期135-141,共7页
针对传统Q-learning算法应用在路径规划中存在收敛速度慢、运行时间长、学习效率差等问题,提出一种将人工势场法和传统Q-learning算法结合的改进Q-learning算法。该算法引入人工势场法的引力函数与斥力函数,通过对比引力函数动态选择奖... 针对传统Q-learning算法应用在路径规划中存在收敛速度慢、运行时间长、学习效率差等问题,提出一种将人工势场法和传统Q-learning算法结合的改进Q-learning算法。该算法引入人工势场法的引力函数与斥力函数,通过对比引力函数动态选择奖励值,以及对比斥力函数计算姿值,动态更新Q值,使移动机器人具有目的性的探索,并且优先选择离障碍物较远的位置移动。通过仿真实验证明,与传统Q-learning算法、引入引力场算法对比,改进Q-learning算法加快了收敛速度,缩短了运行时间,提高了学习效率,降低了与障碍物相撞的概率,使移动机器人能够快速地找到一条无碰撞通路。 展开更多
关键词 移动机器人 路径规划 改进的Q-learning 人工势场法 强化学习
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Automatic recognition of tweek atmospherics and plasma diagnostics in the lower ionosphere with the machine learning method
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作者 Mao Zhang GaoPeng Lu +5 位作者 HaiLiang Huang ZhengWei Cheng YaZhou Chen Steven A.Cummer JiaYi Zheng JiuHou Lei 《Earth and Planetary Physics》 EI CSCD 2023年第3期407-413,共7页
Tweek atmospherics are extremely low frequency and very low frequency pulse signals with frequency dispersion characteristics that originate from lightning discharges and that propagate in the Earth–ionosphere wavegu... Tweek atmospherics are extremely low frequency and very low frequency pulse signals with frequency dispersion characteristics that originate from lightning discharges and that propagate in the Earth–ionosphere waveguide over long distances.In this study,we developed an automatic method to recognize tweek atmospherics and diagnose the lower ionosphere based on the machine learning method.The differences(automatic−manual)in each ionosphere parameter between the automatic method and the manual method were−0.07±2.73 km,0.03±0.92 cm^(−3),and 91±1,068 km for the ionospheric reflection height(h),equivalent electron densities at reflection heights(Ne),and propagation distance(d),respectively.Moreover,the automatic method is capable of recognizing higher harmonic tweek sferics.The evaluation results of the model suggest that the automatic method is a powerful tool for investigating the long-term variations in the lower ionosphere. 展开更多
关键词 machine learning method tweek atmospherics reflection height D-region ionosphere
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Automatic Diagnosis of Polycystic Ovarian Syndrome Using Wrapper Methodology with Deep Learning Techniques
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作者 Mohamed Abouhawwash S.Sridevi +3 位作者 Suma Christal Mary Sundararajan Rohit Pachlor Faten Khalid Karim Doaa Sami Khafaga 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期239-253,共15页
One of the significant health issues affecting women that impacts their fertility and results in serious health concerns is Polycystic ovarian syndrome(PCOS).Consequently,timely screening of polycystic ovarian syndrom... One of the significant health issues affecting women that impacts their fertility and results in serious health concerns is Polycystic ovarian syndrome(PCOS).Consequently,timely screening of polycystic ovarian syndrome can help in the process of recovery.Finding a method to aid doctors in this procedure was crucial due to the difficulties in detecting this condition.This research aimed to determine whether it is possible to optimize the detection of PCOS utilizing Deep Learning algorithms and methodologies.Additionally,feature selection methods that produce the most important subset of features can speed up calculation and enhance the effectiveness of classifiers.In this research,the tri-stage wrapper method is used because it reduces the computation time.The proposed study for the Automatic diagnosis of PCOS contains preprocessing,data normalization,feature selection,and classification.A dataset with 39 characteristics,including metabolism,neuroimaging,hormones,and biochemical information for 541 subjects,was employed in this scenario.To start,this research pre-processed the information.Next for feature selection,a tri-stage wrapper method such as Mutual Information,ReliefF,Chi-Square,and Xvariance is used.Then,various classification methods are tested and trained.Deep learning techniques including convolutional neural network(CNN),multi-layer perceptron(MLP),Recurrent neural network(RNN),and Bi long short-term memory(Bi-LSTM)are utilized for categorization.The experimental finding demonstrates that with effective feature extraction process using tri stage wrapper method+CNN delivers the highest precision(97%),high accuracy(98.67%),and recall(89%)when compared with other machine learning algorithms. 展开更多
关键词 Deep learning automatic detection polycystic ovarian syndrome tri-stage wrapper method mutual information RELIEF CHI-SQUARE
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The State-of-the-Art Review on Applications of Intrusive Sensing,Image Processing Techniques,and Machine Learning Methods in Pavement Monitoring and Analysis 被引量:12
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作者 Yue Hou Qiuhan Li +5 位作者 Chen Zhang Guoyang Lu Zhoujing Ye Yihan Chen Linbing Wang Dandan Cao 《Engineering》 SCIE EI 2021年第6期845-856,共12页
In modern transportation,pavement is one of the most important civil infrastructures for the movement of vehicles and pedestrians.Pavement service quality and service life are of great importance for civil engineers a... In modern transportation,pavement is one of the most important civil infrastructures for the movement of vehicles and pedestrians.Pavement service quality and service life are of great importance for civil engineers as they directly affect the regular service for the users.Therefore,monitoring the health status of pavement before irreversible damage occurs is essential for timely maintenance,which in turn ensures public transportation safety.Many pavement damages can be detected and analyzed by monitoring the structure dynamic responses and evaluating road surface conditions.Advanced technologies can be employed for the collection and analysis of such data,including various intrusive sensing techniques,image processing techniques,and machine learning methods.This review summarizes the state-ofthe-art of these three technologies in pavement engineering in recent years and suggests possible developments for future pavement monitoring and analysis based on these approaches. 展开更多
关键词 Pavement monitoring and analysis The state-of-the-art review Intrusive sensing Image processing techniques Machine learning methods
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Accurate machine learning models based on small dataset of energetic materials through spatial matrix featurization methods 被引量:6
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作者 Chao Chen Danyang Liu +4 位作者 Siyan Deng Lixiang Zhong Serene Hay Yee Chan Shuzhou Li Huey Hoon Hng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第12期364-375,I0009,共13页
A large database is desired for machine learning(ML) technology to make accurate predictions of materials physicochemical properties based on their molecular structure.When a large database is not available,the develo... A large database is desired for machine learning(ML) technology to make accurate predictions of materials physicochemical properties based on their molecular structure.When a large database is not available,the development of proper featurization method based on physicochemical nature of target proprieties can improve the predictive power of ML models with a smaller database.In this work,we show that two new featurization methods,volume occupation spatial matrix and heat contribution spatial matrix,can improve the accuracy in predicting energetic materials' crystal density(ρ_(crystal)) and solid phase enthalpy of formation(H_(f,solid)) using a database containing 451 energetic molecules.Their mean absolute errors are reduced from 0.048 g/cm~3 and 24.67 kcal/mol to 0.035 g/cm~3 and 9.66 kcal/mol,respectively.By leave-one-out-cross-validation,the newly developed ML models can be used to determine the performance of most kinds of energetic materials except cubanes.Our ML models are applied to predict ρ_(crystal) and H_(f,solid) of CHON-based molecules of the 150 million sized PubChem database,and screened out 56 candidates with competitive detonation performance and reasonable chemical structures.With further improvement in future,spatial matrices have the potential of becoming multifunctional ML simulation tools that could provide even better predictions in wider fields of materials science. 展开更多
关键词 Small database machine learning Energetic materials screening Spatial matrix featurization method Crystal density Formation enthalpy n-Body interactions
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Enhancing Parkinson’s Disease Prediction Using Machine Learning and Feature Selection Methods 被引量:1
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作者 Faisal Saeed Mohammad Al-Sarem +4 位作者 Muhannad Al-Mohaimeed Abdelhamid Emara Wadii Boulila Mohammed Alasli Fahad Ghabban 《Computers, Materials & Continua》 SCIE EI 2022年第6期5639-5657,共19页
Several millions of people suffer from Parkinson’s disease globally.Parkinson’s affects about 1%of people over 60 and its symptoms increase with age.The voice may be affected and patients experience abnormalities in... Several millions of people suffer from Parkinson’s disease globally.Parkinson’s affects about 1%of people over 60 and its symptoms increase with age.The voice may be affected and patients experience abnormalities in speech that might not be noticed by listeners,but which could be analyzed using recorded speech signals.With the huge advancements of technology,the medical data has increased dramatically,and therefore,there is a need to apply data mining and machine learning methods to extract new knowledge from this data.Several classification methods were used to analyze medical data sets and diagnostic problems,such as Parkinson’s Disease(PD).In addition,to improve the performance of classification,feature selection methods have been extensively used in many fields.This paper aims to propose a comprehensive approach to enhance the prediction of PD using several machine learning methods with different feature selection methods such as filter-based and wrapper-based.The dataset includes 240 recodes with 46 acoustic features extracted from3 voice recording replications for 80 patients.The experimental results showed improvements when wrapper-based features selection method was used with K-NN classifier with accuracy of 88.33%.The best obtained results were compared with other studies and it was found that this study provides comparable and superior results. 展开更多
关键词 Filter-based feature selection methods machine learning parkinson’s disease wrapper-based feature selection methods
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A Study on Application of Translation and Communicative Methods in German Language Education in Higher Learning Institutes
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作者 Chunhua Fu 《Journal of Contemporary Educational Research》 2020年第2期40-44,共5页
With the continuous development of national‘reforms and opening-up’policy and development of economic globalization,learning and application of foreign languages are becoming increasingly important.Society needs a l... With the continuous development of national‘reforms and opening-up’policy and development of economic globalization,learning and application of foreign languages are becoming increasingly important.Society needs a large number of professional linguistic workers.Therefore,there are higher requirements for new era higher learning institutes which serve as training base for cultivating linguistic talents.Linguistic talents must possess very strong overall quality and skill to meet these requirements.In this context,this study carried out an in-depth analysis and research on translation method commonly used in German language teaching,and communicative method which is increasingly popular in recent years,to contribute to cultivation of German linguistic talents in higher learning institutes of China. 展开更多
关键词 HIGHER learning institutes German TEACHING TRANSLATION method COMMUNICATIVE method
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On the analysis of Good English Learning Methods in English Education
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作者 陈依 《魅力中国》 2014年第2期169-169,共1页
关键词 英语教学 教学方法 阅读教学 阅读知识
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Case Study of a Chinese Girl's English Learning Methods in the American Elementary School
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作者 杨丽 《海外英语》 2017年第6期239-240,共2页
The goal of this research is to explore a more successful method for Mainland Chinese students to learn English.This newmethod will be illustrated by using the experiences of my daughter while a student in an elementa... The goal of this research is to explore a more successful method for Mainland Chinese students to learn English.This newmethod will be illustrated by using the experiences of my daughter while a student in an elementary school in the United States for oneyear.From the analysis of her learning experiences,the following conclusions were drawn:1) Immerse language learning is important tolanguage input.2) Phonics is an effective tool to improve reading for Chinese English 展开更多
关键词 language input learning methods PHONICS case study
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离散四水库问题基准下基于n步Q-learning的水库群优化调度 被引量:2
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作者 胡鹤轩 钱泽宇 +1 位作者 胡强 张晔 《中国水利水电科学研究院学报(中英文)》 北大核心 2023年第2期138-147,共10页
水库优化调度问题是一个具有马尔可夫性的优化问题。强化学习是目前解决马尔可夫决策过程问题的研究热点,其在解决单个水库优化调度问题上表现优异,但水库群系统的复杂性为强化学习的应用带来困难。针对复杂的水库群优化调度问题,提出... 水库优化调度问题是一个具有马尔可夫性的优化问题。强化学习是目前解决马尔可夫决策过程问题的研究热点,其在解决单个水库优化调度问题上表现优异,但水库群系统的复杂性为强化学习的应用带来困难。针对复杂的水库群优化调度问题,提出一种离散四水库问题基准下基于n步Q-learning的水库群优化调度方法。该算法基于n步Q-learning算法,对离散四水库问题基准构建一种水库群优化调度的强化学习模型,通过探索经验优化,最终生成水库群最优调度方案。试验分析结果表明,当有足够的探索经验进行学习时,结合惩罚函数的一步Q-learning算法能够达到理论上的最优解。用可行方向法取代惩罚函数实现约束,依据离散四水库问题基准约束建立时刻可行状态表和时刻状态可选动作哈希表,有效的对状态动作空间进行降维,使算法大幅度缩短优化时间。不同的探索策略决定探索经验的有效性,从而决定优化效率,尤其对于复杂的水库群优化调度问题,提出了一种改进的ε-greedy策略,并与传统的ε-greedy、置信区间上限UCB、Boltzmann探索三种策略进行对比,验证了其有效性,在其基础上引入n步回报改进为n步Q-learning,确定合适的n步和学习率等超参数,进一步改进算法优化效率。 展开更多
关键词 水库优化调度 强化学习 Q学习 惩罚函数 可行方向法
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