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An integrated algorithm to estimate chlorophyll-a concentration in various optical waters using HY-3A CZI

ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING 2025年 225卷 402-422页

作者： Zhang, Lan Ma, Chaofei Chen, Xi Zhang, Chen Li, Qi Ye, Xiaomin Tian, Liqiao Wuhan Univ State Key Lab Informat Engn Surveying Mapping & Re Wuhan 430079 Peoples R China Hubei LuoJia Lab Wuhan 430079 Peoples R China Natl Satellite Ocean Applicat Serv Beijing 100081 Peoples R China

The accurate retrieval of chlorophyll-a (Chla) concentrations in large-scale and highly-dynamic aquatic environments is challenging because of the complex and variable optical water properties, necessitating regionally-tuned or water-type-specific algorithms. In this study, we developed and validated an integrated algorithm to estimate Chla in optically diverse waters using the second-generation Coastal Zone Imager (CZI) onboard the newly launched HY-3A satellite (November 16, 2023). Based on a global in-situ dataset (N = 4,950, Chla range: 0.017-159.07 mg m(-3)), this algorithm first classified the dataset into three water groups using the remote sensing reflectance (R-rs lambda) ratio of 485 and 660 nm, and then applied optimal algorithms for each group: the ocean color index (OCI) algorithm for Group 1 (clear waters dominated by phytoplankton, where R(rs)485/R(rs)660 was >2.5);the normalized difference chlorophyll index (NDCI) and three-band index (TBI) blending algorithm for Group 3 (optically complex waters dominated by non-algal constituents, where R(rs)485/R(rs)660 was <1);and a weighted blending of the two for Group 2 (transitional waters, where R(rs)485/R(rs)660 was between these thresholds). By leveraging the strengths of these algorithms, model testing using in-situ data yielded high accuracy with an R-2 of 0.88 (in log scale), root mean square error (RMSE) of 12.79 mg m(-3), and average unbiased relative error (AURE) of 48.29 %, outperforming any single algorithm. Then, we applied the integrated algorithm to atmospherically corrected CZI R-rs for matchup validation and spatial mapping, further validating the algorithm performance and product quality. The independent validation with in-situ and satellite matchups over Lake Chaohu and Lake Donghu achieved a satisfactory accuracy, with an RMSE of 3.10 mg m(-3) and an AURE of 13.96 %. The CZI-derived Chla maps exhibited well-defined spatial continuity and heterogeneity over lakes and coastal waters, showing

关键词： Chlorophyll-a (Chla) HY-3A CZI integrated algorithm Optical water type (OWT) classification

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Fluid-thermal modeling of hypersonic vehicles via a gas-kinetic BGK scheme-based integrated algorithm

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AEROSPACE SCIENCE AND TECHNOLOGY 2020年 99卷 105748-105748页

作者： Zhou, Di Lu, Zhiliang Guo, Tongqing Shen, Ennan Wu, Jiangpeng Chen, Guoping Nanjing Univ Aeronaut & Astronaut Minist Ind & Informat Technol Key Lab Unsteady Aerodynam & Flow Control Nanjing 210016 Jiangsu Peoples R China Shenyang Aircraft Design & Res Inst Shenyang 110035 Liaoning Peoples R China Nanjing Univ Aeronaut & Astronaut State Key Lab Mech & Control Mech Struct Nanjing 210016 Jiangsu Peoples R China

In our previous paper (doi: 10.1016/***.2019.119016), the gas-kinetic BGK scheme was used to simulate both hypersonic flow and structural heat transfer, between which loose coupling was adopted for solving two-dimensional fluid-thermal problems. To model the unitive and continuous fluid thermal processes more actually, this paper presents a BGK scheme-based integrated algorithm and the research object is extended to three-dimensional hypersonic vehicles. To start with, an appropriate BGK model is constructed for the unified macroscopic governing equations, the effectiveness of which is verified by the Chapman-Enskog expansion analysis. Then following similar procedures in the original scheme, the gas distribution function at each cell interface is derived, from which the numerical fluxes can be evaluated. The dual-time stepping approach, together with an implicit JFNK-BGK method, is applied to efficiently obtain time-accurate solutions. With an effective parallelization strategy that is in line with the integrated algorithm, the computational efficiency is improved. As another aspect which distinguishes from the loosely-coupled methods, the fluid-structure interface conditions are also addressed. For validation, several test cases are investigated, including an individual hypersonic flow, an individual transient heat transfer, and two fluid-thermal problems. By comparison with other methods and analysis of the computed results, features of the developed method are demonstrated. (C) 2020 Elsevier Masson SAS. All rights reserved.

关键词： Fluid-thermal modeling Hypersonic flow Transient heat transfer Gas-kinetic scheme BGK model integrated algorithm

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An integrated algorithm for hypersonic fluid-thermal-structural analysis of aerodynamically heated cylindrical leading edge

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING 2019年第14期233卷 5177-5191页

作者： Li, Jiawei Wang, Jiangfeng Nanjing Univ Aeronaut & Astronaut Coll Aerosp Engn Nanjing 210016 Jiangsu Peoples R China

The accurate and efficient prediction of the fluid-thermal-structural performance of thermal protection systems on hypersonic vehicles to protect against severe aerodynamic heating is attracting increasing worldwide attention. In this paper, a new integrated fluid-structural-thermal investigation based on the finite volume method is proposed to study the thermal behavior of aerodynamically heated cylinder leading edges in hypersonic flows. A unified integral equation system is developed based on the governing equations for the physical processes of aerodynamic heating and structural heat transfer, which is resolved by using an up-wind finite volume method and a new two-thermal-resistance model in one integrated, vectorized computer program. To demonstrate its capability and reliability, applications for steady/unsteady fluid-thermal-structural analysis are demonstrated on aerodynamically heated cylinder leading edges at Ma 6.47. The results show that the steady maximum temperature of the cylinder can reach approximately 648 K at the stagnation point, and the unsteady results are in good agreement with the experimental data and related references. Compared with the partitioned approach, the integrated method shows better computational stability with relatively small sensitivity to mesh scale and time step, reducing the computation time for the same unsteady case by approximately 50%. The present study indicates that the integrated approach has potential for significant improvements and efficiency in predicting long-endurance fluid-structural-thermal problems of hypersonic vehicles.

关键词： Hypersonic integrated algorithm fluid-thermal-structural aerodynamic heating long-endurance

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An integrated algorithm of CCPP Task for Autonomous Mobile Robot under Special Missions

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INTERNATIONAL JOURNAL OF COMPUTATIONAL INTELLIGENCE SYSTEMS 2018年第1期11卷 1357-1368页

作者： Li, Caihong Wang, Zhiqiang Fang, Chun Liang, Zhenying Song, Yong Li, Yibin Shandong Univ Technol Sch Comp Sci & Technol Zibo 255000 Peoples R China Shandong Univ Sch Control Sci & Engn Jinan 250000 Shandong Peoples R China

Due to the difficult problem of avoiding obstacles to achieve the complete coverage path planning (CCPP) for special missions, this paper introduces a novel integrated algorithm of CCPP for autonomous mobile robot under an obstacles-included environment. The algorithm combines cellular decomposition approach and the Standard map together for designing. The cellular decomposition approach is used to simplify the given workplace into smaller sub-regions for coverage via a chaotic path planner. The planner is constructed based on the chaotic Standard map at full mapping and produces the needed trajectories inside each decomposed sub-region. The simulation results verify the effectiveness of the designed method.

关键词： Autonomous mobile robot Complete coverage path planning (CCPP) integrated algorithm Chaotic path planner Cellular decomposition approach The Standard map

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Prediction model of rock mass class using classification and regression tree integrated AdaBoost algorithm based on TBM driving data

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TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 2020年 106卷 103595-103595页

作者： Liu, Quansheng Wang, Xinyu Huang, Xing Yin, Xin Wuhan Univ Sch Civil Engn Key Lab Geotech & Struct Engn Safety Hubei Prov Wuhan 430072 Hubei Peoples R China Wuhan Univ State Key Lab Water Resources & Hydropower Engn S Wuhan 430072 Hubei Peoples R China Chinese Acad Sci State Key Lab Geomech & Geotech Engn Inst Rock & Soil Mech Wuhan 430071 Hubei Peoples R China

The real-time acquisition of surrounding rock information is important for the efficient tunneling and hazard prevention in tunnel boring machines (TBMs). This study presents an ensemble learning model based on classification and regression tree (CART) and AdaBoost algorithm to predict the classification of surrounding rock mass. Statistical indicators (i.e., mean value and standard deviation) of TBM operational parameters were calculated and used as input variables, and the rock mass classification obtained by the hydropower classification (HC) method was used as output variable. To develop the model, a database was established, consisting of 3166 samples collected from the Songhua River Water Conveyance Tunnel. The synthetic minority over-sampling technique (SMOTE) was utilized to address the imbalance ratio of rock mass classifications in the database. The results of the testing set showed that the accuracy and F1-measure of AdaBoost-CART were 0.865 and 0.770, respectively, which are better than the results of the standard CART (0.753 and 0.629, respectively). The application of SMOTE improves the recall of minority classes. Compared with artificial neural networks, k-nearest neighbor, and support vector classifier, the developed AdaBoost-CART model achieves better performance. The variable importance was analyzed to distinguish key features;the results showed that rock mass boreability may not be a major consideration of the HC method. The presented model can provide significant guidance for the real-time acquisition of surrounding rock information during TBM tunneling.

关键词： TBM Rock mass classification integrated algorithm AdaBoost-CART model SMOTE

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Unmanned aerial vehicle trajectory planning by an integrated algorithm in a complex obstacle environment

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING 2017年第11期231卷 2048-2067页

作者： Zhang, Siyu Yu, Jianqiao Mei, Yuesong Sun, Huadong Du, Yongbo Beijing Inst Technol Sch Aerosp Engn 5 South Zhongguancun St Beijing 100081 Peoples R China Hainan Mil Representat Off Hainan 570206 Peoples R China

Both the artificial potential field method and direct method for the optimal control problem have shortcomings in terms of effectiveness and computational complexity for the trajectory-planning problem. This paper proposes an integrated algorithm combining the artificial potential field method and direct method for planning in a complex obstacle-rich environment. More realistic unmanned aerial vehicle dynamics equations, which are rarely applied in the traditional artificial potential field method, are considered in this paper. Furthermore, an additional control force is introduced to transcribe the artificial potential field model into an optimal control problem, and the equality/inequality constraints on the description of the shape of the obstacles are substituted by the repulsive force originating from all the obstacles. The Legendre pseudospectral method and virtual motion camouflage are both utilized to solve the modified optimal control problem for comparison purposes. The algorithm presented in this paper improves the performance of solving the trajectory-planning problem in an obstacle-rich environment. In particular, the algorithm is suitable for addressing some conditions that cannot be considered by the traditional artificial potential field method or direct method individually, such as local extreme value points and a large numbers of constraints. Two simulation examples, a single cube-shaped obstacle and a different-shaped obstacle-rich environment, are solved to demonstrate the capabilities and performance of the proposed algorithm.

关键词： Unmanned aerial vehicle trajectory planning complex environment obstacle-rich integrated algorithm

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An integrated algorithm for hypersonic fluid-thermal-structural numerical simulation

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MODERN PHYSICS LETTERS B 2018年第12-13期32卷

作者： Li, Jia-Wei Wang, Jiang-Feng Nanjing Univ Aeronaut & Astronaut Coll Aerosp Engn Nanjing 210016 Peoples R China

In this paper, a fluid-structural-thermal integrated method is presented based on finite volume method. A unified integral equations system is developed as the control equations for physical process of aero-heating and structural heat transfer. The whole physical field is discretized by using an up-wind finite volume method. To demonstrate its capability, the numerical simulation of Mach 6.47 flow over stainless steel cylinder shows a good agreement with measured values, and this method dynamically simulates the objective physical processes. Thus, the integrated algorithm proves to be efficient and reliable.

关键词： Fluid-structural-thermal aero-heating finite volume method integrated algorithm

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A Dynamic integrated Classification algorithm Based on Big Data Environment

A Dynamic Integrated Classification Algorithm Based on Big D...

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作者： Dan Ma Ji-chun Jiang Wei Wang College of Computer Science & Technology GuiZhou University Guizhou Gas Group Corporation Ltd

With the developing of big data application,classification algorithm has been expanded to distributed datasets from the single *** a dynamic integrated classification algorithm based on big data environment was *** algorithm gain integrated classifiers of high classification accuracy for each local dataset,and dynamically generate the recognition model according to the distribution characteristics of local samples to be *** the application process,after numerous new sample data join the datasets,the classifier performance will drop *** aiming at the above problem,this algorithm will retrain the classification model in the dynamic expansion process of *** to the experimental results,the algorithm proposed in this paper has high classifier training performance and classification *** the same time,it also possesses high adaptive capacity when faced with dynamically changing distributed datasets.

关键词： Classification algorithm integrated algorithm Big Data DIC

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Analysis on the status quo and prospects on the RMB internationalization based on integrated algorithm

Boletin Tecnico/Technical Bulletin

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Boletin Tecnico/Technical Bulletin 2017年第17期55卷 213-218页

作者： Ma, Tao Ding, W.L. School of Tourism and Geographical Sciences Yunnan Normal University Kunming650500 China Institute of Applied Mathematics Qujing Normal University Qujing655011 China Yunnan Normal University Kunming650500 China Collaborative Innovation Center for Geopolitical Setting of Southwest China Borderland Development China

With the rapid imp rovement of China's economic strength and overall national strength, the internationalizat ion of the RMB has been speeding up and its international influence is also on the rise. Th is article analyzed the internationalization tendency of RMB based on the integrated algorith m. First of all, the integration algorith m is briefly introduced and the current status of RMB internationalizat ion is analyzed, including the ach ievements made and the constraints of internationalization development. On this basis, it exp lores the development prospect and development countermeasure of RMB internationalization.

关键词： Development Prospect integrated algorithm RMB Internationalization

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DCS-SOCP-SVM:A Novel integrated Sampling and Classification algorithm for Imbalanced Datasets

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Computers, Materials & Continua 2025年第5期83卷 2143-2159页

作者： Xuewen Mu Bingcong Zhao School of Mathematics and Statistics Xidian UniversityXi’an710071China

When dealing with imbalanced datasets,the traditional support vectormachine(SVM)tends to produce a classification hyperplane that is biased towards the majority class,which exhibits poor *** paper proposes a high-performance classification algorithm specifically designed for imbalanced *** proposed method first uses a biased second-order cone programming support vectormachine(B-SOCP-SVM)to identify the support vectors(SVs)and non-support vectors(NSVs)in the imbalanced ***,it applies the synthetic minority over-sampling technique(SV-SMOTE)to oversample the support vectors of the minority class and uses the random under-sampling technique(NSV-RUS)multiple times to undersample the non-support vectors of the majority *** the above-obtained minority class data set withmultiple majority class datasets can obtainmultiple new balanced data ***,SOCP-SVM is used to classify each data set,and the final result is obtained through the integrated *** results demonstrate that the proposed method performs excellently on imbalanced datasets.

关键词： DCS-SOCP-SVM imbalanced datasets sampling method ensemble method integrated algorithm

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