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Data-Driven Learning Control Algorithms for Unachievable Tracking Problems
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作者 Zeyi Zhang Hao Jiang +1 位作者 Dong Shen Samer S.Saab 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期205-218,共14页
For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to in... For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to investigate solutions using the Ptype learning control scheme. Initially, we demonstrate the necessity of gradient information for achieving the best approximation.Subsequently, we propose an input-output-driven learning gain design to handle the imprecise gradients of a class of uncertain systems. However, it is discovered that the desired performance may not be attainable when faced with incomplete information.To address this issue, an extended iterative learning control scheme is introduced. In this scheme, the tracking errors are modified through output data sampling, which incorporates lowmemory footprints and offers flexibility in learning gain design.The input sequence is shown to converge towards the desired input, resulting in an output that is closest to the given reference in the least square sense. Numerical simulations are provided to validate the theoretical findings. 展开更多
关键词 Data-driven algorithms incomplete information iterative learning control gradient information unachievable problems
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Deep Reinforcement Learning Solves Job-shop Scheduling Problems
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作者 Anjiang Cai Yangfan Yu Manman Zhao 《Instrumentation》 2024年第1期88-100,共13页
To solve the sparse reward problem of job-shop scheduling by deep reinforcement learning,a deep reinforcement learning framework considering sparse reward problem is proposed.The job shop scheduling problem is transfo... To solve the sparse reward problem of job-shop scheduling by deep reinforcement learning,a deep reinforcement learning framework considering sparse reward problem is proposed.The job shop scheduling problem is transformed into Markov decision process,and six state features are designed to improve the state feature representation by using two-way scheduling method,including four state features that distinguish the optimal action and two state features that are related to the learning goal.An extended variant of graph isomorphic network GIN++is used to encode disjunction graphs to improve the performance and generalization ability of the model.Through iterative greedy algorithm,random strategy is generated as the initial strategy,and the action with the maximum information gain is selected to expand it to optimize the exploration ability of Actor-Critic algorithm.Through validation of the trained policy model on multiple public test data sets and comparison with other advanced DRL methods and scheduling rules,the proposed method reduces the minimum average gap by 3.49%,5.31%and 4.16%,respectively,compared with the priority rule-based method,and 5.34%compared with the learning-based method.11.97%and 5.02%,effectively improving the accuracy of DRL to solve the approximate solution of JSSP minimum completion time. 展开更多
关键词 job shop scheduling problems deep reinforcement learning state characteristics policy network
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Effects of Health Education with Problem-Based Learning Approaches on the Knowledge, Attitude, Practice and Coping Skills of Women with High-Risk Pregnancies in Plateau Areas
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作者 Ying Wu Suolang Sezhen +5 位作者 Renqing Yuzhen Hong Wei Zhijuan Zhan Baima Hongying Yuhong Zhang Lihong Liu 《Open Journal of Nursing》 2024年第5期192-199,共8页
Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approach... Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approaches on the knowledge, attitude, practice, and coping skills of women with high-risk pregnancies in this region. Methods: 76 high-risk pregnancy cases were enrolled at Tibet’s Linzhi People’s Hospital between September 2023 and April 2024. 30 patients admitted between September 2023 and December 2023 were selected as the control group and were performed with regular patient education. 46 patients admitted between January 2024 and April 2024 were selected as the observation group and were performed regular patient education with problem-based learning approaches. Two groups’ performance on their health knowledge, attitude, practice and coping skills before and after interventions were evaluated, and patient satisfaction were measured at the end of the study. Results: There was no statistical significance (P P P Conclusions: Health education with problem-based learning approaches is worth promoting as it can help high-risk pregnant women in plateau areas develop better health knowledge, attitude and practice and healthier coping skills. Also, it can improve patient sanctification. 展开更多
关键词 Plateau Areas Patients with High-Risk Pregnancies problem-Based learning Health Education Health Knowledge Attitude and Practice Coping Skills
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Solving Geometry Problems via Feature Learning and Contrastive Learning of Multimodal Data
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作者 Pengpeng Jian Fucheng Guo +1 位作者 Yanli Wang Yang Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1707-1728,共22页
This paper presents an end-to-end deep learning method to solve geometry problems via feature learning and contrastive learning of multimodal data.A key challenge in solving geometry problems using deep learning is to... This paper presents an end-to-end deep learning method to solve geometry problems via feature learning and contrastive learning of multimodal data.A key challenge in solving geometry problems using deep learning is to automatically adapt to the task of understanding single-modal and multimodal problems.Existing methods either focus on single-modal ormultimodal problems,and they cannot fit each other.A general geometry problem solver shouldobviouslybe able toprocess variousmodalproblems at the same time.Inthispaper,a shared feature-learning model of multimodal data is adopted to learn the unified feature representation of text and image,which can solve the heterogeneity issue between multimodal geometry problems.A contrastive learning model of multimodal data enhances the semantic relevance betweenmultimodal features and maps them into a unified semantic space,which can effectively adapt to both single-modal and multimodal downstream tasks.Based on the feature extraction and fusion of multimodal data,a proposed geometry problem solver uses relation extraction,theorem reasoning,and problem solving to present solutions in a readable way.Experimental results show the effectiveness of the method. 展开更多
关键词 Geometry problems multimodal feature learning multimodal contrastive learning automatic solver
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A Dual Discriminator Method for Generalized Zero-Shot Learning
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作者 Tianshu Wei Jinjie Huang 《Computers, Materials & Continua》 SCIE EI 2024年第4期1599-1612,共14页
Zero-shot learning enables the recognition of new class samples by migrating models learned from semanticfeatures and existing sample features to things that have never been seen before. The problems of consistencyof ... Zero-shot learning enables the recognition of new class samples by migrating models learned from semanticfeatures and existing sample features to things that have never been seen before. The problems of consistencyof different types of features and domain shift problems are two of the critical issues in zero-shot learning. Toaddress both of these issues, this paper proposes a new modeling structure. The traditional approach mappedsemantic features and visual features into the same feature space;based on this, a dual discriminator approachis used in the proposed model. This dual discriminator approach can further enhance the consistency betweensemantic and visual features. At the same time, this approach can also align unseen class semantic features andtraining set samples, providing a portion of information about the unseen classes. In addition, a new feature fusionmethod is proposed in the model. This method is equivalent to adding perturbation to the seen class features,which can reduce the degree to which the classification results in the model are biased towards the seen classes.At the same time, this feature fusion method can provide part of the information of the unseen classes, improvingits classification accuracy in generalized zero-shot learning and reducing domain bias. The proposed method isvalidated and compared with othermethods on four datasets, and fromthe experimental results, it can be seen thatthe method proposed in this paper achieves promising results. 展开更多
关键词 Generalized zero-shot learning modality consistent DISCRIMINATOR domain shift problem feature fusion
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A Deep Learning Method to Process Scattered Field Data in Biomedical Imaging System
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作者 Jing Wang Naike Du Xiuzhu Ye 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期213-218,共6页
This paper proposed a deep-learning-based method to process the scattered field data of transmitting antenna,which is unmeasurable in inverse scattering system because the transmitting and receiving antennas are multi... This paper proposed a deep-learning-based method to process the scattered field data of transmitting antenna,which is unmeasurable in inverse scattering system because the transmitting and receiving antennas are multiplexed.A U-net convolutional neural network(CNN)is used to recover the scattered field data of each transmitting antenna.The numerical results proved that the proposed method can complete the scattered field data at the transmitting antenna which is unable to measure in the actual experiment and can also eliminate the reconstructed error caused by the loss of scattered field data. 展开更多
关键词 inverse problem scattered field deep learning
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A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization
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作者 Sheng Qi Rui Wang +3 位作者 Tao Zhang Xu Yang Ruiqing Sun Ling Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1342-1357,共16页
Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.... Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.As a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec separately.Nevertheless,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables Mask.However,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is optimized.In data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between data.Inspired by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these SLMOPs.TELSO mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast convergence.Experi-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed. 展开更多
关键词 Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.
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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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Adaptive Multi-Step Evaluation Design With Stability Guarantee for Discrete-Time Optimal Learning Control 被引量:1
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作者 Ding Wang Jiangyu Wang +2 位作者 Mingming Zhao Peng Xin Junfei Qiao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第9期1797-1809,共13页
This paper is concerned with a novel integrated multi-step heuristic dynamic programming(MsHDP)algorithm for solving optimal control problems.It is shown that,initialized by the zero cost function,MsHDP can converge t... This paper is concerned with a novel integrated multi-step heuristic dynamic programming(MsHDP)algorithm for solving optimal control problems.It is shown that,initialized by the zero cost function,MsHDP can converge to the optimal solution of the Hamilton-Jacobi-Bellman(HJB)equation.Then,the stability of the system is analyzed using control policies generated by MsHDP.Also,a general stability criterion is designed to determine the admissibility of the current control policy.That is,the criterion is applicable not only to traditional value iteration and policy iteration but also to MsHDP.Further,based on the convergence and the stability criterion,the integrated MsHDP algorithm using immature control policies is developed to accelerate learning efficiency greatly.Besides,actor-critic is utilized to implement the integrated MsHDP scheme,where neural networks are used to evaluate and improve the iterative policy as the parameter architecture.Finally,two simulation examples are given to demonstrate that the learning effectiveness of the integrated MsHDP scheme surpasses those of other fixed or integrated methods. 展开更多
关键词 Adaptive critic artificial neural networks Hamilton-Jacobi-Bellman(HJB)equation multi-step heuristic dynamic programming multi-step reinforcement learning optimal control
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Learning-Based Metaheuristic Approach for Home Healthcare Optimization Problem
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作者 Mariem Belhor Adnen El-Amraoui +1 位作者 Abderrazak Jemai François Delmotte 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期1-19,共19页
This research focuses on the home health care optimization problem that involves staff routing and scheduling problems.The considered problem is an extension of multiple travelling salesman problem.It consists of find... This research focuses on the home health care optimization problem that involves staff routing and scheduling problems.The considered problem is an extension of multiple travelling salesman problem.It consists of finding the shortest path for a set of caregivers visiting a set of patients at their homes in order to perform various tasks during a given horizon.Thus,a mixed-integer linear programming model is proposed to minimize the overall service time performed by all caregivers while respecting the workload balancing constraint.Nevertheless,when the time horizon become large,practical-sized instances become very difficult to solve in a reasonable computational time.Therefore,a new Learning Genetic Algorithm for mTSP(LGA-mTSP)is proposed to solve the problem.LGA-mTSP is composed of a new genetic algorithm for mTSP,combined with a learning approach,called learning curves.Learning refers to that caregivers’productivity increases as they gain more experience.Learning curves approach is considered as a way to save time and costs.Simulation results show the efficiency of the proposed approach and the impact of learning curve strategy to reduce service times. 展开更多
关键词 Home healthcare scheduling and routing problem OPTIMIZATION multiple travelling salesman problem learning curves genetic algorithm
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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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Proposing Effective Problem-Based Learning(PBL)Problems by Reimplementing Open-Source Projects
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作者 Yin Zhang Yuli Zhao +2 位作者 Hai Yu Dongming Chen Zhiliang Zhu 《计算机教育》 2021年第12期19-24,共6页
Recently,Problem-Based Learning(PBL)has been regarded as a possible way towards effective educational changes in Chinese universities.However,problems have been exposed in the adoption of PBL,such as choosing effectiv... Recently,Problem-Based Learning(PBL)has been regarded as a possible way towards effective educational changes in Chinese universities.However,problems have been exposed in the adoption of PBL,such as choosing effective PBL problems.The purpose of this paper is to provide a possible solution to the formulation of PBL problems for computer science courses,which is to reimplement open-source projects(ROSP).A case is demonstrated by showing how ROSP was adopted in a practical intercourse-level PBL course module.This paper contributes to a new PBL problem formulation method for promoting PBL in a practical way for Chinese universities. 展开更多
关键词 Engineering Education problem-Based learning problem Formulation Method
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Research on Problems and Strategies of"Learning"from the Perspective of Physical Education Curriculum
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作者 Ran Cheng Ran Sun Qiang Li 《Journal of Contemporary Educational Research》 2021年第4期67-73,共7页
Using literature review,questionnaire survey,mathematical statistics and other research methods,combined with the previous research results of the research team,systematically sort out the problems of"learning&qu... Using literature review,questionnaire survey,mathematical statistics and other research methods,combined with the previous research results of the research team,systematically sort out the problems of"learning"in the"learning,training,competition,and use"physical education curriculum,and how to solve the problems.The strategic research of the Chinese Academy of Sciences aims to promote the scientificization of"learning"in the teaching of physical education courses,thereby improving the quality and efficiency of physical education courses. 展开更多
关键词 Physical Education Curriculum learning problems and Strategies
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The Problems of Senior Three Students' "Mute-Crux" in English Learning in China
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作者 LUO Ming-li 《Sino-US English Teaching》 2012年第5期1139-1144,共6页
关键词 英语学习 学生 中国 静音 高三 英语教学 传统观念 英语教师
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Emotional Problems and Countermeasures in English Learning
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作者 XU Li-mei CHEN Qiang 《Sino-US English Teaching》 2014年第12期893-897,共5页
关键词 情感因素 英语学习 学习过程 情感交流 学习效果 有效使用
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Research of the Learning Problems of Contemporary University Students
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作者 Li Li Jie Wang 《International English Education Research》 2014年第7期95-96,共2页
关键词 大学生 学习问题 高等教育 教育普及
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Research of the Learning Problems of Contemporary University Students
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作者 Li Li Jie Wang 《International English Education Research》 2014年第6期53-54,共2页
关键词 大学生 学习问题 高等教育 教育大众化
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The Problems and its Countermeasures of Autonomous Language Learning Center
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作者 聂鉴锋 《海外英语》 2014年第2X期111-112,122,共3页
With the popularity of Computer Assisted Language Learning(CALL),autonomous language learning centers have been established in the universities throughout the country.However,there are many problems exist in the pract... With the popularity of Computer Assisted Language Learning(CALL),autonomous language learning centers have been established in the universities throughout the country.However,there are many problems exist in the practice of the autonomous language learning center.This essay tries to discuss the problems and its countermeasures with an aim of improving College English learning and teaching by the example of autonomous language learning center in Nanyang Institute of Technology. 展开更多
关键词 COLLEGE English AUTONOMOUS LANGUAGE learning cente
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PBL(Problem-based Learning)教学法道路规划与几何设计教学中的应用与探索 被引量:1
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作者 张兰芳 方守恩 王俊骅 《教育教学论坛》 2016年第39期127-128,共2页
立足于道路规划与几何设计信息量大,涉及专业基础知识广、实践性强等特点,将PBL教学法在教学中进行了应用与探索,从教师设计问题、组建学习小组、问题探索与交流、教师总结评价等方面进行了教学设计和应用研究,实践证明PBL教学有助于提... 立足于道路规划与几何设计信息量大,涉及专业基础知识广、实践性强等特点,将PBL教学法在教学中进行了应用与探索,从教师设计问题、组建学习小组、问题探索与交流、教师总结评价等方面进行了教学设计和应用研究,实践证明PBL教学有助于提高学生的自主创新学习能力及学习的积极性,显著提升了教学效果。 展开更多
关键词 PBL(problem BASED learning)教学法 道路规划与几何设计 自主学习
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Shallow water bathymetry based on a back propagation neural network and ensemble learning using multispectral satellite imagery
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作者 Sensen Chu Liang Cheng +4 位作者 Jian Cheng Xuedong Zhang Jie Zhang Jiabing Chen Jinming Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期154-165,共12页
The back propagation(BP)neural network method is widely used in bathymetry based on multispectral satellite imagery.However,the classical BP neural network method faces a potential problem because it easily falls into... The back propagation(BP)neural network method is widely used in bathymetry based on multispectral satellite imagery.However,the classical BP neural network method faces a potential problem because it easily falls into a local minimum,leading to model training failure.This study confirmed that the local minimum problem of the BP neural network method exists in the bathymetry field and cannot be ignored.Furthermore,to solve the local minimum problem of the BP neural network method,a bathymetry method based on a BP neural network and ensemble learning(BPEL)is proposed.First,the remote sensing imagery and training sample were used as input datasets,and the BP method was used as the base learner to produce multiple water depth inversion results.Then,a new ensemble strategy,namely the minimum outlying degree method,was proposed and used to integrate the water depth inversion results.Finally,an ensemble bathymetric map was acquired.Anda Reef,northeastern Jiuzhang Atoll,and Pingtan coastal zone were selected as test cases to validate the proposed method.Compared with the BP neural network method,the root-mean-square error and the average relative error of the BPEL method can reduce by 0.65–2.84 m and 16%–46%in the three test cases at most.The results showed that the proposed BPEL method could solve the local minimum problem of the BP neural network method and obtain highly robust and accurate bathymetric maps. 展开更多
关键词 BATHYMETRY back propagation neural network ensemble learning local minimum problem multispectral satellite imagery
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