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Projections of summer light rain frequency in typical terrain over eastern China under wind speed constraint

Science China Earth Sciences 2024年第6期67卷 1885-1894页

作者： Xuechen DONG daoyi GONG Cuicui SHI Institute of Disaster Risk Science Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster MOEFaculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of National Safety and Emergency Management Beijing Normal UniversityBeijing 100875China School of Systems Science Beijing Normal UniversityBeijing 100875China

The variation in near-surface wind speed is a key dynamic parameter in the orographic effect of precipitation over eastern *** this study,we used the latest high-resolution outputs from six GCMs in CMIP6-HighResMIP to evaluate the performance of high-resolution models in simulating the orographic precipitation characteristics of typical mountainous areas in summer over eastern *** orographic precipitation under warming scenarios was projected and constrained according to observational *** results indicated that during the contemporary climate reference period(1979-2009),although the relationship between model-simulated near-surface wind speed and orographic light rain frequency was consistently stable,the sensitivity of the orographic light rain frequency to surface wind variability was generally underestimated,with a deviation approximately 24.1% lower than the observational *** estimated orographic light rain frequency corrected based on the observed near-surface wind speed under a 1.5℃ warming scenario,was 36.1% lower than that of the contemporary period;this reduction was 8.6 times that without the wind speed constraint(4.2%).The MRI-AGCM3-2-S model,with a longer dataset,demonstrated relatively stable reductions in orographic light rain frequency under different warming scenarios(1.5℃,2℃,3℃,and 4℃)after the application of wind speed *** all cases,the reductions exceeded those for the predictions made without the wind speed constraint.

关键词： Frequency of orographic light rain HighResMIP High-resolution projection Observational constraint Eastern China

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Signifi cant Association Between Arctic Oscillation and Winter Wildfi res in Southern China

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International Journal of Disaster Risk Science 2024年第5期15卷 820-830页

作者： Meng Meng daoyi Gong Yunfei Lan Qichao Yao Lamei Shi Zhou wang National Institute of Natural Hazards Ministry of Emergency Management of China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Institute of Disaster Risk Science Beijing Normal University Faculty of Geographical Science Beijing Normal University

The recent increase of regional wildfire occurrences has been associated with climate change. In this study, we investigated the association between the February to March wildfire points and burned area in the southern region of China(20°N–30°N and 105°E–115°E) and the simultaneous Arctic Oscillation(AO) index during 2001–2022 and 2001–2020, respectively. After removing the El Ni?o-Southern Oscillation and Indian Ocean Dipole signals, time series of the regional mean fire points and burned area over the study area is significantly correlated with the AO index at-0.37 and-0.47, significant at the 0.1 level. Precipitation significantly aff ects wildfire variations. The positive AO could trigger a southeastward Rossby wave train and induce anomalous cyclone activity approximately located in the area encompassed by 15°N–27°N and 85°E–100°E. This outcome could help to enhance the southern branch trough and results in positive precipitation anomalies in southern China. This increasing moisture is conductive to reducing wildfire risks, vice versa. Our results are potentially useful for strengthening the understanding of the mechanisms of wildfire occurrences in southern China.

关键词： Arctic Oscillation Climate change ENSO Southern China wildfires

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车辆跟驰模型的发展综述

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山东理工大学学报（自然科学版） 2022年第5期36卷 75-80页

作者：王道意宇仁德闫兴奎胡婧晖朱燕华崔淑艳山东理工大学交通与车辆工程学院山东淄博255049

对车辆跟驰理论进行概述,分析车辆在非自由状态行驶下的跟驰特性。跟驰模型在近70年的发展历程中,吸引了交通工程学、统计物理学、心理学等不同领域的专家参与研究,建模时考虑因素由单一到多元、由简单到复杂,随着模型的不断发展,逐渐... 详细信息

对车辆跟驰理论进行概述,分析车辆在非自由状态行驶下的跟驰特性。跟驰模型在近70年的发展历程中,吸引了交通工程学、统计物理学、心理学等不同领域的专家参与研究,建模时考虑因素由单一到多元、由简单到复杂,随着模型的不断发展,逐渐贴合于实际交通状况;分析了刺激-反应类模型、安全距离Gipps模型、优化速度FVD模型、元胞自动机模型,重点剖析了四类模型的建模思路和改进过程,对经典跟驰模型进行总结对比;展望了跟驰模型未来发展的趋势,指出在无人驾驶和智能网联的大环境下,基于机器学习的安全跟驰状态辨识方法研究、基于机器学习的跟驰特性研究及基于多元信息融合的跟驰模型构建等将是未来的发展方向。

关键词：跟驰模型交通工程跟驰建模

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Pattern recognition of quantum information based on patterndistance

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Journal of Systems Engineering and Electronics 2005年第4期16卷 917-923页

作者： Dong daoyi Chen Zonghai Jiang Shengxiang Dept. of Automation Univ. of Science and Technology of China Hefei 230027 P. R. China Dept. of Mechanical and Industrial Engineering Univ. of Illinois at Urbana-Champaign Urbana IL 61801 USA

Looking upon every encoding state of quantum information systems as a quantum information pattern, A kind of pattern-distance between different patterns as a measurement of comparability of quantum information patterns is defined, and two kinds of recognition algorithms based on pattern-distance for quantum information are proposed. They can respectively recognize quantum information with known objective pattern and unknown objective pattern. In the two algorithms, the phases and occurrence probabilities of different eigenpattems of quantum information are sufficiently considered. Two examples demonstrate the feasibility and effectiveness of the two recognition methods. These algorithms point out a new and important path for applications of quantum information and pattern recognition.

关键词： quantum information quantum information pattern pattern-distance recognition.

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Wind Erosion Climate Change in Northern China During 1981-2016

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International Journal of Disaster Risk Science 2020年第4期11卷 484-496页

作者： Feng Zhang Jing'ai wang Xueyong Zou Rui Mao daoyi Gong Xingya Feng State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China MOE Engineering Research Center of Desertification and Blown-Sand Control Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Wind erosion is largely controlled by climate *** this study,we examined the influences of changes in wind speed,soil wetness,snow cover,and vegetation cover related to climate change on wind erosion in northern China during 1981–*** used the wind erosion force,defined as wind factor in the Revised Wind Erosion Equation Model,to describe the effect of wind speed on wind *** results show that wind erosion force presented a long-term decreasing trend in the southern Northwest,northern Northwest,and eastern northern China during 1981–*** the Gobi Desert,the wind erosion force presented for 1981–1992 a decreasing trend,for 1992–2012 an increasing trend,and thereafter a weakly decreasing *** comparison to wind speed,soil wetness and snow cover had weaker influences on wind erosion in northern China,while vegetation cover played a significant role in the decrease of wind erosion in the eastern northern China during 1982–2015.

关键词： Northern China RWEQ model Wind erosion Wind erosion force Heavy wind frequency

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Coherent H^(∞)Control for Linear Quantum Systems With Uncertainties in the Interaction Hamiltonian

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IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 432-440页

作者： Chengdi Xiang Shan Ma Sen Kuang daoyi Dong the School of Automation Hangzhou Dianzi UniversityHangzhou 310018China the School of Automation Central South UniversityChangsha 410083China the Department of Automation University of Science and Technology of ChinaHefei 230027China the School of Engineering and Information Technology University of New South WalesCanberra ACT 2600Australia

This work conducts robust H^(∞)analysis for a class of quantum systems subject to perturbations in the interaction Hamiltonian.A necessary and sufficient condition for the robustly strict bounded real property of this type of uncertain quantum system is *** paper focuses on the study of coherent robust H^(∞)controller design for quantum systems with uncertainties in the interaction *** desired controller is connected with the uncertain quantum system through direct and indirect couplings.A necessary and sufficient condition is provided to build a connection between the robust H^(∞)control problem and the scaled H^(∞)control problem.A numerical procedure is provided to obtain coefficients of a coherent *** example is presented to illustrate the controller design method.

关键词： Coherent feedback control robust control uncertain quantum system

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Quantum state tomography from observable time traces in closed quantum systems

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Control Theory and Technology 2024年第2期22卷 222-234页

作者： Shuixin Xiao Yuanlong wang Qi Yu Jun Zhang daoyi Dong Ian R.Petersen University of Michigan–Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai200240China School of Engineering The Australian National UniversityCanberraACT2601Australia Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China Centre for Quantum Computation and Communication Technology(Australian Research Council) Centre for Quantum DynamicsGriffith UniversityBrisbaneQLD4111Australia School of Engineering and Technology University of New South WalesCanberraACT2600Australia

The task to estimate all the parameters of an unknown quantum state, also called quantum state tomography, is essential for characterizing and controlling quantum systems. In this paper, we utilize observable time traces to identify the initial quantum state of a closed quantum system, based on the state space approach in the control theory. In the informationally complete scenario, we show that with a linear regression estimation (LRE), the mean squared error (MSE) scales as , where N is the resource number. In the informationally incomplete scenario, we introduce regularization LRE to perform the state tomography task. We employ PBH test to demonstrate that closed quantum systems with only one observable are informationally incomplete and propose using observables, where d is the dimension of the quantum state, for informational completeness. Numerical examples demonstrate the effectiveness of our method.

关键词： Quantum state tomography Time trace Quantum system identification

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基于SVM的弯道行车安全辨识

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河南科技 2021年第20期40卷 9-12页

作者：胡婧晖宇仁德王道意崔淑艳朱燕华闫兴奎山东理工大学交通与车辆工程学院山东淄博255049

车辆运行安全状态辨识能够很好地提前规避风险,在弯道这样事故多发的路形上显得尤为重要。通过ADAMS软件仿真车速、弯道半径、超高对车辆过弯行驶状态的影响并进行预处理,形成辨识模型的训练集,再分别用网格搜索法、遗传算法、粒子群算... 详细信息

车辆运行安全状态辨识能够很好地提前规避风险,在弯道这样事故多发的路形上显得尤为重要。通过ADAMS软件仿真车速、弯道半径、超高对车辆过弯行驶状态的影响并进行预处理,形成辨识模型的训练集,再分别用网格搜索法、遗传算法、粒子群算法对支持向量机(Support Vector Machines,SVM)模型进行优化,建立安全状态辨识模型。试验结果表明,优化后的SVM模型可以有效辨识出弯道行驶安全状态,识别率超过90%。

关键词：弯道行车安全性支持向量机辨识

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Domain of attraction of nonlinear functional difference systems

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Chinese Science Bulletin 1999年第2期44卷 121-123页

作者： daoyi Xu Anshi Xu Sichuan Union Univ Dept Math Chengdu 610064 Peoples R China

The domain of attraction of nonlinear functional difference systems is studied. A sufficient condition for determining the domain of attraction is given based on a non-negative parameter matrix whose spectral radius ... 详细信息

关键词： functional differece equations domain of attraction stability.

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基于Fluent的矿用电磁先导阀内部流场的仿真与分析

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煤炭技术 2025年第1期44卷 253-257页

作者：潘占仁王义毛道义王兆霆刘小龙北京天玛智控科技股份有限公司北京101399

在使用中,电磁先导阀存在一些如能耗、渗漏和气蚀等问题,导致关键零部件的耐久性和可靠性不足。利用计算流体力学仿真技术对某新型电磁先导阀在高压高速工况时容易出现的冲击、能耗和气蚀现象,在不同压差条件下完成了流场仿真,展示了流... 详细信息

在使用中,电磁先导阀存在一些如能耗、渗漏和气蚀等问题,导致关键零部件的耐久性和可靠性不足。利用计算流体力学仿真技术对某新型电磁先导阀在高压高速工况时容易出现的冲击、能耗和气蚀现象,在不同压差条件下完成了流场仿真,展示了流体在模拟区域内的压力分布情况、流体在不同位置的速度分布情况、湍流在流体中的分布情况以及流体中气相的体积分数分布情况,对比不同条件下的云图,发现提高出口压力对先导阀结构存在的问题有一定的改善作用。

关键词：电磁先导阀球阀流场模拟 Fluent

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