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Landscape ecological risk assessment and its driving factors in the Weihe River basin,China

Journal of Arid Land 2024年第5期16卷 603-614页

作者： CHANG Sen WEI Yaqi DAI Zhenzhong XU Wen WANG Xing DUAN Jiajia ZOU Liang zhao guorong REN Xiaoying FENG Yongzhong College of Agronomy Northwest A&F UniversityYangling 712100China

Weihe River basin is of great significance to analyze the changes of land use pattern and landscape ecological risk and to improve the ecological basis of regional *** on land use data of the Weihe River basin in 2000,2010,and 2020,with the support of Aeronautical Reconnaissance Coverage Geographic Information System(ArcGIS),GeoDa,and other technologies,this study analyzed the spatial-temporal characteristics and driving factors of land use pattern and landscape ecological *** showed that land use structure of the Weihe River basin has changed significantly,with the decrease of cropland and the increase of forest land and construction *** the past 20 a,cropland has decreased by 7347.70 km2,and cropland was mainly converted into forest land,grassland,and construction *** fragmentation and dispersion of ecological landscape pattern in the Weihe River basin were improved,and land use pattern became more ***,landscape ecological risk of the Weihe River basin has been *** landscape ecological risk area decreased by 19,177.87 km2,high landscape ecological risk area decreased by 3904.35 km2,and moderate and low landscape ecological risk areas continued to *** is worth noting that landscape ecological risks in the upper reaches of the Weihe River basin are still relatively serious,especially in the contiguous areas of high ecological risk,such as Tianshui,Pingliang,Dingxi areas and some areas of Ningxia Hui Autonomous *** ecological risk showed obvious spatial dependence,and high ecological risk area was *** the driving factors,population density,precipitation,normalized difference vegetation index(NDVI),and their interactions are the most important factors affecting the landscape ecological risk of the Weihe River *** findings significantly contribute to our understanding of the ecological dynamics in the Weihe River basin,providing crucial insights for sustainable mana

关键词： land use ecological risk spatiotemporal distribution geographic detector driving factors

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Optimal fusion state estimator for a multi-sensor system subject to multiple packet dropouts

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Journal of Control and Decision 2021年第2期8卷 175-183页

作者： Xu Han Jianhua Lu guorong zhao Naval Aviation University YantaiPeople’s Republic of China

In this note,we study the state estimation problem for a multi-sensor system subject to multiple packet dropouts.A novel optimal distributed fusion estimator is derived by applying a resending mechanism and a parallel information filtering *** is shown that the proposed distributed fusion estimator has smaller estimation error covariance and less computation complexity when compared with the centralised Kalman like estimator with multiple intermittent measurements.

关键词： Multi-sensor system multiple packet dropouts distributed fusion estimator centralised Kalman-like estimator

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Effects of NO_(2) and SO_(2) on the secondary organic aerosol formation fromβ-pinene photooxidation

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Journal of Environmental Sciences 2024年第2期136卷 151-160页

作者： Xiangyu Zang zhaoyan Zhang Yingqi zhao Gang Li Hua Xie Weiqing Zhang guorong Wu Xueming Yang Ling Jiang Zhang Dayu School of Chemistry Dalian University of TechnologyDalian 116024China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry School of ScienceSouthern University of Science and TechnologyShenzhen 518055China

Elucidating the effects of anthropogenic pollutants on the photooxidation of biogenic volatile organic compounds is crucial to understanding the fundamental mechanisms of secondary organic aerosol(SOA)***,the impacts of NO_(2)and SO_(2)on SOA formation from the photooxidation of a representative monoterpene,β-pinene,were investigated by a number of laboratory *** results indicated NO_(2)enhanced the SOA mass concentrations and particle number concentrations under both low and highβ-pinene *** could be rationalized that the increased O_(3)concentrations upon the NO_(x)photolysis was helpful for the generation of more amounts of O_(3)-oxidized products,which accelerated the SOA nucleation and *** with NO_(2),the promotion of the SOA yield by SO_(2)was mainly reflected in the increase of mass concentration,which might be due to the elimination of the newly formed particles by the initially formed *** observed low oxidation degree of SOA might be attributed to the fast growth of SOA,resulting in the uptake of less oxygenated gas-phase species onto the particle *** present findings have important implications for SOA formation affected by anthropogenic–biogenic interactions in the ambient atmosphere.

关键词： Secondary organic aerosol Volatile organic compound Anthropogenic pollutant Beta-pinene Photooxidation

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Anti-cracking Property of EVA-modified Polypropylene Fiber-reinforced Concrete Under Thermal-cooling Cycling Curing

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1109-1118页

作者：刘斯凤 YANG Siyu KONG Yaning WAN Tingting zhao guorong School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education Tongji UniversityShanghai 200092China

In order to investigate the synergistic effect of re-dispersible powder-ethylene-vinyl acetate copolymer(EVA) and polypropylene fiber on the crack resistance of concrete under thermal fatigue loading, the compressive strength, ultimate tensile strength, ultimate tensile strain and tensile modulus of elasticity were tested. In addition, ultrasonic method and scanning electron microscope analysis were used to explain the microstructure mechanism. The results show that polypropylene fiberreinforced concrete presents a better performance on crack resistance than ordinary concrete, and the synergism of EVA and polypropylene fiber can improve the anti-cracking ability of concrete further.

关键词： anti-cracking property EVA-modified polypropylene fiber-reinforced concrete thermal-cooling cycling curing

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Overburden failure and the prevention of water and sand inrush during coal mining under thin bedrock

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Mining Science and Technology 2011年第5期21卷 733-736页

作者： Yang Weifeng Xia Xiaohong zhao guorong Ji Yubin Shen Dingyi School of Resources and Geosdences China University of Mining ＆ Technology Xuzhou 221116 China

Coal mining under thin bedrock or thick unconsolidated soil layers brings mining problems related to these special geological conditions. The meaning of the term ''thin bedrock'' is defined through the thick- ness statistics of the coal seam and the bedrock layer. The coal-bearing strata having thick, unconsoli- dated aquifers and thin bedrock located at the Taiping Coal Mine in Shandong province were taken as a geological prototype for subsequent study. The geological, hydro-geological and engineering character- istics of the thin bedrock were analyzed. An engineering geological model was than established. Overbur- den failure and the development of ''Three Zones'' were studied by physical model tests. The rupture pattern and rock failure were analyzed for mining conditions under thin bedrock. The height of the caving zone and the freely flowing water fractured zone of different mining thicknesses were separately calcu- lated. The results show that a mining thickness greater than 3.5 m causes the height of the freely flowing water fractured zone to be sufficient to touch the weathered zone and the bottom of the Quaternary sys- tem aquifer, to various degrees. This, then, would lead to water and sand inrush into the working face. Measures to prevent water and sand flow inrush disasters by eliminating the power source are put fore- word. A field dewatering scheme was designed and observational data were obtained. The dewatering project had an obvious effect and the water level at working face number 8309 dropped to a safe level. The average draw down of the groundwater was observed to be 7.86 m. This showed that the dewatering project played a role in decreasing the hydraulic pressure and ensuring safety mining.

关键词：覆岩破坏薄基岩止水松散含水层裂隙带高度采煤煤炭开采煤层厚度

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多网络约束下NNS分布式融合估计器设计

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北京航空航天大学学报 2023年第2期49卷 229-241页

作者：赵国荣顾昊伦韩旭高超海军航空大学岸防兵学院烟台264001 中国人民解放军第91001部队北京100854

针对节点量测增益衰减、节点能量受限与系统模型不确定3种网络约束下具有随机通信时滞和非固定丢包率的组网导航系统(NNS)分布式状态融合估计问题,将增益衰减程度描述为统计特性已知的随机变量,将模型不确定描述为系统矩阵中的乘性有色... 详细信息

针对节点量测增益衰减、节点能量受限与系统模型不确定3种网络约束下具有随机通信时滞和非固定丢包率的组网导航系统(NNS)分布式状态融合估计问题,将增益衰减程度描述为统计特性已知的随机变量,将模型不确定描述为系统矩阵中的乘性有色噪声,将减小能耗描述为降低节点数据传输率。分别在邻节点端和目标节点端引入2种不同的线性编码器以解决丢包与时滞问题。建立丢包率与同时传输信息的节点数目之间的函数关系,将邻节点在过去有限个时刻的量测值进行线性编码后再传输,以补偿丢包与降低传输率导致的信息损失。目标节点把在同一采样周期内获取的来自同一邻节点的多个量测值按时间戳进行线性编码,以解决通信时滞导致的信息多余。基于2次线性编码建立增广系统模型,设计最小方差意义下局部无偏估计器,利用最优矩阵加权融合法得到全局融合估计器,推导得到融合估计误差协方差收敛的充分条件及次优传输率。通过算例仿真验证所提算法的有效性。

关键词：随机通信时滞非固定丢包率分布式融合估计线性编码组网导航系统多网络约束

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基于节点分级的NNSs跨层MAC协议设计

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系统工程与电子技术 2022年第7期44卷 2329-2340页

作者：顾昊伦赵国荣姚金博高超海军航空大学岸防兵学院山东烟台264001 国电南瑞科技股份有限公司江苏南京211106

针对组网导航系统(networked navigation systems,NNSs)中节点高速移动、能量受限及通信时滞的问题,融合了基于移动汇聚节点的交叉路由树构建及链式分簇相结合的路由协议(cross routing tree construction based on mobile sink and cha... 详细信息

针对组网导航系统(networked navigation systems,NNSs)中节点高速移动、能量受限及通信时滞的问题,融合了基于移动汇聚节点的交叉路由树构建及链式分簇相结合的路由协议(cross routing tree construction based on mobile sink and chain clustering,CRTCC),设计了一种基于节点分级的跨层媒介访问控制协议(medium access control protocol based on graded nodes,GN-MAC)。GN-MAC采取了基于竞争的媒介访问方式,结合CRTCC协议特点定义GN-MAC包格式并完成具有多级别节点的自适应虚拟分簇,同时设计了改进型节点移动性检测算法,作出了最优簇间切换决策,提出了基于优先级的竞争机制以及多信道通信机制。最后通过算例仿真,验证了GN-MAC在节点高速移动和多移动节点情况下,时滞和能耗得到了有效的控制。

关键词：组网导航系统跨层媒介访问控制协议节点分级虚拟分簇移动性检测

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基于DMPC的多无人机轨迹跟踪与避碰切换控制

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航空兵器 2023年第6期30卷 64-74页

作者：赵超轮戴邵武何云风刘帅赵国荣海军航空大学山东烟台264000 海军航空大学青岛校区山东青岛266000

多无人机系统在编队飞行过程中往往会遇到突发的静态或动态的障碍物威胁,如何实现对障碍的规避是多无人机系统所必须解决的关键问题之一,为此本文提出一种带有模式切换的分布式模型预测控制算法。根据有无碰撞风险设计出跟踪、避碰两种... 详细信息

多无人机系统在编队飞行过程中往往会遇到突发的静态或动态的障碍物威胁,如何实现对障碍的规避是多无人机系统所必须解决的关键问题之一,为此本文提出一种带有模式切换的分布式模型预测控制算法。根据有无碰撞风险设计出跟踪、避碰两种控制模式及切换策略,其中,跟踪模式以跟踪轨迹为目标,相应算法能保证系统渐近稳定;避碰模式则以避碰为首要目标,通过触发式引入避碰约束来实现无人机与障碍间的避碰。相较传统单一模式下的预测控制算法,本文方法可使无人机更有效地规避预先未知的大型障碍,具有保守性低、计算时间短等优势,最后利用6架四旋翼仿真验证了算法的有效性。

关键词：多无人机轨迹跟踪避碰模型预测控制模式切换

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庄浪县天然林保护和人工造林问题探讨

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农业科技与装备 2022年第6期 18-19页

作者：赵国荣庄浪县通边林场甘肃平凉744669

以庄浪县为例,论述森林与人类、人工造林与天然林保护之间关系,分析人工造林地块、树种、密度选择中应注意的问题,提出人工造林要考虑长远利益,不能盲目追求生长速度快的树种,可在有条件的区域选择适宜的名贵树种,以提高人工造林的综合... 详细信息

以庄浪县为例,论述森林与人类、人工造林与天然林保护之间关系,分析人工造林地块、树种、密度选择中应注意的问题,提出人工造林要考虑长远利益,不能盲目追求生长速度快的树种,可在有条件的区域选择适宜的名贵树种,以提高人工造林的综合价值。

关键词：人工造林天然林保护问题探讨庄浪县

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BLOCK DIAGONAL FORM AND BLOCK DIAGONAL CONTROLLER OF NONLINEAR SYSTEMS

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Chinese Journal of Aeronautics 1997年第1期10卷 51-57页

作者： zhao guorong Zhang Fuen(Dept. of Automatic Control, Harbin Institute of Technology, Harbin, China, 150001)Gu Wenjing(Naval Aeronautical Engineering Academy, Yantai, Shantong, China, 264001) Dept. of Automatic Control Harbin Institute of Technology Harbin 150001 China Nav. Aero. Engineering Academy Yantai Shantong 264001 China

A block diagonal form about a nonlinear system is defined. Based on the de finition, a design method ca1led block diagonal controller (BDC) is proPOsed bo feedbacklinearization. Thus, a linearization design of a class of nonlinear system can be simply re-alized. The result of design has been proved by mathematical simulation of a certain anti-ship missile.

关键词： feedback linearization nonlinear systems flight control controllers

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