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2000-2020年黄河流域水-能源-粮食系统耦合协调时空演变特征

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水土保持研究 2024年第1期31卷 354-362页

作者：王锐祝笑笑彭艳艳赵素霞肖东洋河南理工大学测绘与国土信息工程学院河南焦作454000 河南理工大学黄河生态文明与高质量发展研究院河南焦作454000

[目的]探讨黄河流域水—能源—粮食系统的耦合协调时空演化特征,可为定量评估流域高质量发展和区域可持续发展提供科学依据。[方法]通过耦合协调度模型分析水—能源—粮食系统的综合发展水平和耦合协调特征,并利用灰色关联度对各子系统... 详细信息

[目的]探讨黄河流域水—能源—粮食系统的耦合协调时空演化特征,可为定量评估流域高质量发展和区域可持续发展提供科学依据。[方法]通过耦合协调度模型分析水—能源—粮食系统的综合发展水平和耦合协调特征,并利用灰色关联度对各子系统内部指标进行排序,进而判断对水—能源—粮食系统耦合协调度的影响程度。[结果](1)黄河流域水—能源—粮食系统的综合发展指数呈上升趋势,水资源子系统波动幅度最大。(2) 2000—2020年黄河流域水—能源—粮食系统耦合协调度从初级协调向良好协调阶段发展;不同省区间的系统耦合协调发展水平差异较为明显,整体上可表现为上游地区>中下游地区。(3)各子系统与系统耦合协调度的影响程度排名可表示为水资源子系统>粮食子系统>能源子系统,其中水资源子系统内部指标与系统耦合协调度关联度均在85%以上,水资源子系统相对其他子系统的严格管理尤为重要。[结论]水—能源—粮食系统的耦合协调发展水平有待提高,为促进系统协调发展和流域高质量发展应综合考虑各子系统的相互作用关系。

关键词：黄河流域水—能源—粮食系统耦合协调度模型灰色关联度分析

Automatic segmentation algorithm for high-spatial-resolution remote sensing images based on self-learning super-pixel convolutional network

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International Journal of Digital Earth 2022年第1期15卷 1101-1124页

作者： Zenan Yang Haipeng Niu Liang Huang xiaoxuan Wang Liangxin Fan dongyang xiao School of Surveying and Land Information Engineering Henan Polytechnic UniversityJiaozuoHenanPeople’s Republic of China Research Centre of Arable Land Protection and Urban-rural High-quality Development of of Yellow River Basin HenanPeople’s Republic of China Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunmingPeople’s Republic of China Surveying and Mapping Geo-Informatics Technology Research Center on Plateau Mountains of Yunnan Higher Education KunmingPeople’s Republic of China Key Laboratory of Spatio-temporal Information and Ecological Restoration of Mines of Natural Resources of the People's Republic of China Henan Polytechnic UniversityJiaozuoPeople’s Republic of China

Super-pixel algorithms based on convolutional neural networks with fuzzy C-means clustering are widely used for high-spatial-resolution remote sensing images ***,this model requires the number of clusters to be set manually,resulting in a low automation degree due to the complexity of the iterative clustering *** address this problem,a segmentation method based on a self-learning super-pixel network(SLSP-Net)and modified automatic fuzzy clustering(MAFC)is ***-Net performs feature extraction,non-iterative clustering,and gradient reconstruction.A lightweight feature embedder is adopted for feature extraction,thus expanding the receiving range and generating multi-scale *** matching is used for non-iterative clustering,and the overfitting of the network model is overcome by adaptively adjusting the gradient weight parameters,providing a better irregular super-pixel neighborhood *** optimized density peak algorithm is adopted for *** on the obtained super-pixel image,this maximizes the robust decision-making interval,which enhances the automation of regional ***,prior entropy fuzzy C-means clustering is applied to optimize the robust decision-making and obtain the final segmentation *** results show that the proposed model offers reduced experimental complexity and achieves good performance,realizing not only automatic image segmentation,but also good segmentation results.

关键词： Deep convolution neural network model super-pixel algorithm automatic fuzzy clustering prior entropy fuzzy C-Means clustering algorithm remote sensing images

Scaly-sided Merganser(Mergus squamatus)equalizes foraging costs with depth by switching foraging tactics

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Avian Research 2023年第4期14卷 685-694页

作者： Peizhong Liu Meihan Liu dongyang xiao Ying He Rong Fan Cai Lu Li Wen Qing Zeng Guangchun Lei Centre for East Asian-Australasian Flyway Studies Beijing Forestry UniversityBeijing100083China School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing100083China College of Forestry Beijing Forestry UniversityBeijing100083China The People’s Government of Shangqing Town Yingtan335004China NSW Department of Planning Industry and EnvironmentScienceEconomics and Insights DivisionSydney2150Australia Department of Earth and Environmental Sciences Macquarie UniversitySydney2109Australia

Throughout evolutionary history,animals are finely tuned to adjust their behaviors corresponding to environmental *** flexibility represents an important component of a species'adaptive capacity in the face of rapid anthropogenetic environmental change,and knowledge of animal behaviors is increasingly recognized in conservation *** aquatic ecosystem,variation of water depth is a key factor affecting the availability of food;thus,the foraging behaviors of many waterbirds,especially *** this study,we compared the foraging behaviors of the Scaly-sided Merganser(Mergus squamatus),an endangered migratory diving duck endemic to East Asia,in habitats with different water depths(Shallow waters:0–40 cm;Deep waters:40–300 cm),using video camera records obtained from the known wintering sites during three winters from 2018 to ***,the energy expenditure of foraging behavior profile and energy intake based on fish sizes were calculated to study the foraging *** total,200 effective video footages that contained 1086 min with 17,995 behaviors and 163 events of catching fish were *** showed that:1)time length for fishing(including eye-submerging,head-dipping,diving and food handling)of *** in shallow waters was significantly more than in deep waters;2)*** spent significantly more time for preparing(including vigilance,preening and swimming)in deep waters than in shallow waters;3)the mean catch rate was 0.28 fish/min in shallow waters,which is significantly higher than the value of 0.13 fish/min in deep waters;4)despite the distinct foraging behavior profiles and energy intakes,*** showed similar energetics in shallow and deep *** concluded that *** is a good example of behavioral flexibility that aligns with expectations of optimal foraging theory,in that it behaves in accordance to resource availability in different environments,resulting in high foraging efficiency.

关键词： Foraging behavior adaption Foraging energetics In-stream habitats Migratory waterbird

UNIFORM SUPERCONVERGENCE ANALYSIS OF A TWO-GRID MIXED FINITE ELEMENT METHOD FOR THE TIME-DEPENDENT BI-WAVE PROBLEM MODELING D-WAVE SUPERCONDUCTORS

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Journal of Computational Mathematics 2024年第2期42卷 415-431页

作者： Yanmi Wu dongyang Shi PLA Information Engineering University Zhengzhou 450001China School of Mathematics and Information Sciences Yantai UniversityYantai 264005China

In this paper,a two-grid mixed finite element method(MFEM)of implicit Backward Euler(BE)formula is presented for the fourth order time-dependent singularly perturbed Bi-wave problem for d-wave superconductors by the nonconforming EQ_(1)^(rot) *** this approach,the original nonlinear system is solved on the coarse mesh through the Newton iteration method,and then the linear system is computed on the fine mesh with Taylor’s *** on the high accuracy results of the chosen element,the uniform superclose and superconvergent estimates in the broken H^(1)-norm are derived,which are independent of the negative powers of the perturbation parameter appeared in the considered *** results illustrate that the computing cost of the proposed two-grid method is much less than that of the conventional Galerkin MFEM without loss of accuracy.

关键词： Time-dependent Bi-wave problem Two-grid mixed finite element method Uniform superclose and superconvergent estimates

CONVERGENCE ANALYSIS OF NONCONFORMING QUADRILATERAL FINITE ELEMENT METHODS FOR NONLINEAR COUPLED SCHRODINGER-HELMHOLTZ EQUATIONS

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Journal of Computational Mathematics 2024年第4期42卷 979-998页

作者： dongyang Shi Houchao Zhang School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

The focus of this paper is on two novel linearized Crank-Nicolson schemes with nonconforming quadrilateral finite element methods(FEMs)for the nonlinear coupled Schrodinger-Helmholtz *** L^(2) and H^(1) estimates of orders O(h^(2)+τ^(2))and O(h^(2)+τ^(2))are derived respectively without any grid-ratio condition through the following two *** is that a time-discrete system is introduced to split the error into the temporal error and the spatial error,which leads to optimal temporal error estimates of order O(τ^(2))in L^(2) and the broken H^(1)-norms,as well as the uniform boundness of numerical solutions in L^(∞) *** other is that a novel projection is utilized,which can iron out the difficulty of the existence of the consistency *** leads to derive optimal spatial error estimates of orders O(h^(2))in L^(2)-norm and O(h)in the broken H^(1)-norm under the H^(2) regularity of the solutions for the time-discrete *** last,two numerical examples are provided to confirm the theoretical ***,h is the subdivision parameter,and τ is the time step.

关键词： Schrodinger-Helmholtz equations Nonconforming FEMs Linearized Crank-Nicolson scheme Optimal error estimates

Drivers of farmers’behavior toward compensation scheme for cultivated land protection in chengdu pilot area,China

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Ecosystem Health and Sustainability 2021年第1期7卷 416-431页

作者： Haipeng Niu dongyang xiao Suxia Zhao Department of Land Resources Management School of Surveying and Land Information Engineering of Henan Polytechnic UniversityJiaozuoChina Department of Arable Land Protection and Land Spatial Planning in the Yellow River Basin Research Centre of Arable Land Protection and Urban-Rural HighQuality Development of Yellow River BasinHenan Polytechnic UniversityJiaozuoChina

Studying farmers’behavior affected by economic incentive is necessary to promote positive behavior among farmers toward protecting the quantity,quality,and ecological environment of cultivated *** this study,we investigated the current situation regarding economic incentive policies for cultivated land protection,which has attracted the attention of Chinese ***,we focused on the earliest pilot scheme(i.e.,Cultivated Land Protection Fund,CLPF)implemented in the west of China since 2008 to empirically analyze farmers’*** analysis and path analysis methods were applied,with data collected from 296 *** results showed that positive actions,including the enhancement of initiatives to protect cultivated land,the improvement of ecological environment of cultivated land,and the investment in agricultural infrastructure,have been adopted by farmers since the implementation of the ***,gender,education level,labor force size,cultivated land area,migration out of traditional farming areas,average annual household income,and farmers’knowledge of the policy impacted significantly on farmers’*** the premise of comprehensive consideration of the diversity of farmers’livelihoods,new communication technologies and sufficient funds,we suggested that a long-term and sustainable project should be established at the national level to effectively compensate farmers.

关键词： Farmers’behavior ecological environment compensation influencing factors cultivated land protection

Dynamic modeling and RBF neural network compensation control for space flexible manipulator with an underactuated hand

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Chinese Journal of Aeronautics 2024年第3期37卷 417-439页

作者： dongyang SHANG xiaopeng LI Meng YIN Fanjie LI School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

In space operation,flexible manipulators and gripper mechanisms have been widely used because of light weight and ***,the vibration caused by slender structures in manipulators and the parameter perturbation caused by the uncertainty derived from grasping mass variation cannot be *** existence of vibration and parameter perturbation makes the rotation control of flexible manipulators difficult,which seriously affects the operation accuracy of ***’s more,the complex dynamic coupling brings great challenges to the dynamics modeling and vibration *** solve this problem,this paper takes the space flexible manipulator with an underactuated hand(SFMUH)as the research *** dynamics model considering flexibility,multiple nonlinear elements and disturbance torque is established by the assumed modal method(AMM)and Hamilton’s principle.A dynamic modeling simplification method is proposed by analyzing the nonlinear ***’s more,a sliding mode control(SMC)method combined with the radial basis function(RBF)neural network compensation is ***,the control law is designed using a saturation function in the control method to weaken the chatter *** the help of neural networks to identify the uncertainty composition in the SFMUH,the tracking accuracy is *** results of ground control experiments verify the advantages of the control method for vibration suppression of the SFMUH.

关键词： Space flexible manipulator RBF neural network Underactuated hand Dynamic models Model simplification

Performance Prediction Based Workload Scheduling in Co-Located Cluster

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2043-2067页

作者： dongyang Ou Yongjian Ren Congfeng Jiang School of Computer Science and Technology Hangzhou Dianzi UniversityHangzhou310018China

Cloud service providers generally co-locate online services and batch jobs onto the same computer cluster,where the resources can be pooled in order to maximize data center resource *** to resource competition between batch jobs and online services,co-location frequently impairs the performance of online *** study presents a quality of service(QoS)prediction-based schedulingmodel(QPSM)for *** performance prediction of QPSM consists of two parts:the prediction of an online service’s QoS anomaly based on XGBoost and the prediction of the completion time of an offline batch job based on ***-line service QoS anomaly prediction is used to evaluate the influence of batch jobmix on on-line service performance,and batch job completion time prediction is utilized to reduce the total waiting time of batch *** the same number of batch jobs are scheduled in experiments using typical test sets such as CloudSuite,the scheduling time required by QPSM is reduced by about 6 h on average compared with the first-come,first-served strategy and by about 11 h compared with the random scheduling *** with the non-co-located situation,QPSM can improve CPU resource utilization by 12.15% and memory resource utilization by 5.7% on *** show that the QPSM scheduling strategy proposed in this study can effectively guarantee the quality of online services and further improve cluster resource utilization.

关键词： Co-located cluster workload scheduling online service batch jobs data center

Chemical Constituents of Schisandra rubriflora Rehd. et Wils.

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Journal of Integrative Plant Biology 2005年第3期47卷 362-367页

作者： Gan-PengLI Jing-FengZHAO Yong-QiangTU xiao-dongyang Hong-BinZHANG LiangLI SchoolofPharmacy YunnanUniversityKunming650091China／／SchoolofChemistryandBiotechnologyYunnanNationalitiesUniversityKunming650031China SchoolofPharmacy YunnanUniversityKunming650091China DepartmentofChemistry NationalLaboratoryofAppliedOrganicChemistryLanzhouUniversityLanzhou730000China

Abstract: Schisandra rubriflora Rehd. et Wils. is a traditional Chinese medicine. To search for new and bioactive components from traditional Chinese medicines and provide scientific evidence for taxonomy, the chemical constituents of the plant were investigated by various column chromatography methods (silica gel, Sephadex LH-20, and RP-18). From the aerial parts of S. rubriflora, three new megastigmane glycosides, namely (3S, 5R, 6S, 9R)-megastigmane-3, 9-diol 3-O-[α-L-arabionfuranosyl-(1→6)-β-D-glucopyranoside] (1), 7-megastigmene-3-ol-9-one 3-O-[α-L-arabionfuranosyl-(1→6)-β-D-glucopyranoside] (2), and megastigmane-3α, 4β, 9σ-triol 3-O-β-D-glucopyranoside (3), along with 14 known compounds, were isolated. The structures of the new compounds were elucidated by a combination of spectroscopic and chemical methods.

关键词： alangionoside megastigmane glycosides Schisandra rubriflora Rehd. et Wils Schisandraceae