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Strong law of large Numbers for Weighted Sums of Random Variables and Its Applications in EV Regression Models

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Journal of Systems Science & Complexity 2022年第1期35卷 342-360页

作者： PENG Yunjie ZHENG xiaoqian YU Wei HE Kaixin WANG Xuejun School of Mathematical Sciences Anhui UniversityHefei 230601China. Wendian College Anhui UniversityHefei 230601China

This paper mainly studies the strong convergence properties for weighted sums of extended negatively dependent(END,for short)random *** sufficient conditions to prove the strong law of large numbers for weighted sums of END random variables are *** particular,the authors obtain the weighted version of Kolmogorov type strong law of large numbers for END random variables as a *** results that the authors obtained generalize the corresponding ones for independent random variables and some dependent random *** an application,the authors investigate the errors-in-variables(EV,for short)regression models and establish the strong consistency for the least square *** studies are conducted to demonstrate the performance of the proposed procedure and a real example is analysed for illustration.

关键词： EV regression models extended negatively dependent random variables strong consistency strong law of large numbers weighted sums

Effect of joint structure and slope direction on the development of collapsing gully in tuffaceous sandstone area in South China

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International Soil and Water Conservation Research 2020年第2期8卷 131-140页

作者： Yusong Deng xiaoqian Duan Shuwen Ding Chongfa Cai Forestry College of Guangxi University NanningGuangxi530004China College of Resources and Environment of Huazhong Agricultural University WuhanHubei430070China

This study focuses on the collapsing gullies in tuffaceous sandstone area and investigates the slope di-rection and morphological characteristics of the main and branch gullies. Furthermore, we assess the structural characteristics of the rock joints within this area, including their strike, dip direction and dip angle. The results show that there are 405 collapsing gullies in the study area. The slope directions associated with collapsing gullies and the directions of the main gullies largely fall within the ranges of NE20°-NE90°, SE90°-SE160°, SW240°-SW270°, and NW270°-NW290°. The collapsing gullies include 1103 branch gullies in total, most of which have directions that fall within the ranges of NE20°-NE40°, NE50°-NE70°, NW280°-NW300°, and NW330°-NW350°. The joints in the bedrock are directional and regional, and they can be divided into two main groups. The number of southward dip directions is greater than the number of northward dip directions, and most of the measured dip angles are greater than 60°. The mean dip angle is greatest for joints with measured strike values of NW280°-NW290°, with a value of 85.2°. The development of collapse gullies is affected by both the slope direction and joints. The slope direction determines the direction of the main gullies, with a correlation coefficient of 0.809 (Pllies are mainly affected by joints, with a correlation coefficient of 0.876 (Plso influences the degree of development of the collapsing gullies, and the average depth of the gullies that parallel the dominant joint orientation is significantly larger than that of gullies with other directions. Moreover, the average depth of the gullies associated with the dip angle of 85.2° measured relative to the joint strike is 6.89 m, which is significantly greater than that associated with lower dip angles. The dip angles of joints have an important effect on the infiltration of water, and high dip angles accelerate the er

关键词： Soil erosion Joint Slope direction Main gully Branch gully

Flexible cone impact dynamics based on space probe-cone docking mechanism

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Science China(Physics,Mechanics & Astronomy) 2014年第1期57卷 128-137页

作者： HAN Wei HUANG YiYong CHEN xiaoqian ZHANG Xiang College of Aerospace Science and Engineering National University of Defense Technology

The theoretical model of docking impact dynamics based on flexible cone is presented according to Foppl-von Karman＇s non-linear differential equations and Hertz contact theory. Finite diflerence technique is used to solve this theoretical model. Results of the theoretical model show good agreement with the experimental and ANSYS/lS-DYNA simulation results. In ad- dition, the influence of flexible cone parameters on impact process is discussed based on theoretical model systemically.

关键词： autonomous rendezvous servicing simulation soft-docking large deflections of thin flat plates

Observation of small-scale processes over shelf break in the East China Sea

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Chinese Science Bulletin 2005年第24期50卷 2885-2890页

作者： ZHOU lei TIAN Jiwei ZHANG xiaoqian Physical Oceanography laboratory Ocean University of China Qingdao 266003 China

The turbulent dissipation along with tempera- ture and salinity was measured on board R/V Dong Fang Hong 2 over the shelf break of the East China Sea from March 7 to 9, 2004. Applying the Turner angle, it is found that the ‘diffusive’ double diffusion, salt-fingering, and stable stratification coexist in the upper water column of about 50 m. Below that depth, there exists weak salt-fingering. The turbulent dissipation rates are enhanced along the ray paths of M2 internal tides emanating from the shelf break with values ranging from 1.0×10?9 W·kg?1 to 1.2×10?6 W·kg?1. The corresponding diapycnal mixing rates are from 1×10?6 m2·s?1 to 1×10?2 m2·s?1. The spatially averaged mixing rate over the whole observation section is 2.3×10?3 m2·s?1, which is much larger than 1×10?5 m2·s?1 of the background diapy- cnal mixing rate in the open ocean.

关键词：中国东海陆架间断小规模突起两倍扩散率湍流耗散海水盐度温度

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云控制水肥药械智能监控平台的设计与实现

农机化研究 2025年第2期47卷 75-80页

作者：林秀君胡佳宁孙涛张晓乾任振辉河北农业大学机电工程学院河北保定071001 石家庄鑫农机械有限公司石家庄052400

随着我国农业现代化水平的提高,以水肥药械为核心的现代农业服务体系成为未来行业发展的方向。为此,采用B/S结构模式,使用Django框架,选用MySQl数据库,设计并实现了一种云控制水肥药械智能监控平台。平台拥有完善的机构、数据交互、用... 详细信息

随着我国农业现代化水平的提高,以水肥药械为核心的现代农业服务体系成为未来行业发展的方向。为此,采用B/S结构模式,使用Django框架,选用MySQl数据库,设计并实现了一种云控制水肥药械智能监控平台。平台拥有完善的机构、数据交互、用户和权限等管理功能,可实现水肥药械的数字化管理;嵌入了基于Bi-lSTM与lightGBM融合的参考作物蒸散量预测方法,可实现对作物灌溉的实时预测;增加了作物施肥计算公式以及施肥用药数据库,可为用户对肥、药的施用提供科学的参考依据。实际运行及性能测试结果表明:平台的架构和模块设计合理,功能较全面和灵活,可有效满足设施园区对于水肥药械的管理需求,推动现代化农业发展。

关键词：水肥药械一体化智能监控平台云控制 Django框架

A Stackelberg strategy for continuous-time mixed H2/H∞ control problem with time delay

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Control Theory and Technology 2018年第3期16卷 191-202页

作者： xiaoqian lI Wei WANG Juanjuan XU Huanshui ZHANG School of Control Science and Engineering Shandong University Jinan Shandong 250061 China

This paper is concerned with the mixed H2/H∞ control with linear continuous time system and time delay. To deal with this, we presents a Stackelberg strategy by treating the control input and the disturbance as leader and follower, respectively. The leader＇s control strategy minimizes the cost function which is in H2 norm and the follower＇s control strategy maximizes the cost function which is in H∞ norm. The main technique of this paper is deal with the noncausal relationship of the variables caused by time delay in the control input by introducing two costates to capture the future information and one state to capture the past information. Through theory analyzing, the Stackelberg strategy exists uniquely. Moreover, with the assistance of the extended state space expression, the explicit expression of the strategy is obtained.

关键词： Mixed H2/H∞ control continuous-time system Stackelberg strategy time delay

Why are COVID-19 travel bubbles a tightrope walk?An investigation based on the Trans-Tasmanian case

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Communications in Transportation Research 2023年第1期3卷 37-43页

作者： xiaoqian Sun Sebastian Wandelt Anming Zhang National Key laboratory of CNS/ATM School of Electronic and Information EngineeringBeihang UniversityBeijing100191China Sauder School of Business University of British ColumbiaVancouverBCCanada

The COVID-19 pandemic has hit the transportation sector hard;particularly air transportation,as a major mode of long-distance transportation,has been affected *** the dawn of COVID-19,politicians and policy makers have discussed the idea of introducing travel bubbles between countries(or counties),to allow for a continued exchange of people and *** eponymous Trans-Tasmanian travel bubble is a major example,involving quarantine-free travel between Australia and New *** both countries have tried to form a travel bubble various times,recurring setbacks and difficulties were *** October 2021,this ambitious project presumably has come to an end,with both countries announcing the essential capitulation of their COVIDZero strategies and a planned opening towards broader international *** this study,we perform a close investigation of the history behind the Trans-Tasmanian travel bubble as an on-off relationship,identifying a set of drivers for the serious problems involving a sustainable setup and *** develop a framework which represents important factors for successful travel bubbles and believe that the satisfaction of all factors at once is extremely *** results and insights are not specific to the Trans-Tasmanian case only,although it is taken as a running example,but can be generalized to various scales and *** hope that our study contributes to the literature by improving our understanding of the highly buzzed travel bubble concept,while providing empirical evidence for the troubles that inherently make such bubbles a tightrope walk.

关键词： COVID-19 Travel bubble Australia New Zealand

Effects of recombinant adeno-associated viruses expressing human vascular endothelial growth factor 165 on spinal cord injury

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Neural Regeneration Research 2010年第21期5卷 1623-1628页

作者： Chen Zhang Hui Qiang xiaoqian Dang Kunzheng Wang First Department of Orthopedics Second Affiliated Hospital Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China Department of Orthopedics Shaanxi Provincial People's Hospital Third Affiliated Hospital Medical School of Xi'an Jiaotong UniversityXi'an 710068 Shaanxi Province China

Numerous studies have confirmed that vascular endothelial growth factor （VEGF） improves the function of neural cells following spinal cord injury （SCI）. However, some studies have also verified that VEGF cannot significantly induce the increase in vascular density at or surrounding the lesion, and that VEGF therapy exacerbated secondary damage following SCI. Based on the dual effects of VEGF on SCI, we constructed the recombinant adeno-associated viruses （rAAV）-hVEGF165-IRES-human recombinant green fluorescent protein （hrGFP）（AAV-VEGF） and rAAV-IRES-hrGFP （AAV-GFP）. Our results suggested that rAAV expressed hVEGFles, and a low dose of VEGF relieved increased vascular permeability, improved microcirculation in the local spinal cord, lessened spinal cord edema, and decreased neuronal apoptosis. These results verified that the releasing effects of the rAAV virus vector had protective effects on the spinal cord.

关键词： spinal cord injury neural regeneration adeno-associated virus vascular endothelia growth factor cell apoptosis

Antiglycative and anti-inflammatory effects of lipophilized tyrosol derivatives

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Food Production, Processing and Nutrition 2020年第1期2卷 280-286页

作者： xiaoqian Hu Mingfu Wang Fereidoon Shahidi School of Public Health Xiamen UniversityXiamen 361102FujianChina College of Food Science and Technology Shanghai Ocean UniversityShanghai 201306China Department of Biochemistry Memorial University of NewfoundlandSt.John’sNL A1B 3X9Canada

To expand the application of tyrosol,a series of lipophilized tyrosol derivatives were synthesized via esterification of tyrosol with fatty acids of different chain *** antiglycative activity of tyrosol esters so prepared was subsequently examined in the bovine serumalbumin/glucose system.A quasi-parabolic shape was observed when the activity was plotted against alkyl chain ***,the anti-inflammatory effects of these derivatives were evaluated against methylglyoxalinduced inflammation in RAW264.7 *** same trend on anti-inflammatory activity was found as in the antiglycation *** results showed that tyrosol esters with C12:0 and C14:0 were two most efficient ones among all the tested ***,some lipophilized tyrosol derivatives were stronger antiglycative and anti-inflammatory agents compared to the parent compound,tyrosol.

关键词： Tyrosyl esters lipophilization Glycation Methylglyoxal Inflammation Phenolipids