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Estimating the optimal vegetation coverage for the dominant tree and shrub species over China's northwest drylands

Science China Earth Sciences 2024年第5期67卷 1500-1517页

作者： Zhongdian ZHANG Xiaoxu JIA Ping zhu Mingbin HUANG lidong REN Ming’an SHAO School of Geographic Sciences Xinyang Normal UniversityXinyang 464000China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Yellow River Delta Modern Agricultural Engineering Laboratory Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China

Anthropogenic revegetation is an effective way to control soil erosion and restore degraded ecosystems in China's northwest drylands(NWD).However,excessive vegetation cover expansion has long been known to increase evapotranspiration,leading to reduced local water availability,which can in turn threaten the health and services of restored *** the optimal vegetation coverage(OVC)is critical for balancing the trade-off between plant growth and water consumption in water-stressed areas,yet quantitative assessments over the entire NWD are still *** this study,a modified Biome BioGeochemical Cycles(Biome-BGC)model was used to simulate the long-term(1961–2020)dynamics of actual evapotranspiration(ET_(a)),net primary productivity(NPP),and leaf area index(LAI)for the dominant non-native tree(*** and ***)and shrub(*** and ***)species at 246 meteorological sites over *** modified model incorporated the Richards equation to simulate transient unsaturated water flow in a multilayer soil module,and both soil and eco-physiological parameters required by the model were validated using field-observed ETadata for each *** distributions of OVC(given by the mean maximum LAI,LAI_(max))for the dominant species were determined within three hydrogeomorphic sub-areas(i.e.,the loess hilly-gully sub-area,the windy and sandy sub-area,and the desert sub-area).The modified Biome-BGC model performed well in terms of simulating ET_(a) dynamics for the four plant *** distributions of mean ET_a,NPP,and LAI_(max)generally exhibited patterns similar to mean annual precipitation(MAP).In the loess hilly-gully sub-area(MAP:210 to 710 mm),the OVC respectively ranged from 1.7 to 2.9 and 0.8 to 2.9 for *** and *** the windy and sandy sub-area(MAP:135 to 500 mm),the OVC ranged from 0.3 to 3.3,0.5 to 2.6 and 0.6 to 2.1for ***,*** and ***,*** the desert sub-

关键词： Optimal vegetation coverage Water balance Leaf area index Biome-BGC model Dryland

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Resource Allocation Strategy Based on Matching Game

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ZTE Communications 2020年第4期18卷 10-17页

作者： DENG Xu zhu lidong National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

With the development of satellite communication technology,the traditional resource allocation strategies are difficult to meet the requirements of resource utilization *** order to solve the optimization problem of resource allocation for multi-layer satellite networks in multi-user scenarios,we propose a new resource allocation scheme based on the many-to-many matching *** scheme is different from the traditional resource allocation strategies that just consider a trade-off between the new call blocking probability and the handover call failure *** on different preference lists among different layers of medium earth orbit(MEO) satellites,low earth orbit(LEO) satellites,base stations and users,we propose the corresponding algorithms from the perspective of quality of experience(QoE).The simulation results show that the many-to-many matching game scheme can effectively improve both the resource utilization efficiency and QoE,compared with the one-to-one and many-to-one matching algorithms.

关键词： satellite network resource allocation many-to-many matching game preference lists quality of experience

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Zircon U-Pb dating,Geochemical Features of the Halunwusu Composite Granites at the Northern Edge of Southern Qilian,Qinghai

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 92-93页

作者： TAO Gang zhu lidong YANG Wenguang LI Zhiwu XIE Long Institute of Sedimentary Geology Chengdu University of TechnologyChengdu610059 State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059

1 Introduction Halunwusu Composite Granites,locates in the northern margin of Belt,between the North Qaidam block and the Central Qilian block,with two phases of magmatic *** granites mainly consisits of the Early

关键词： Pb Zircon U-Pb dating,Geochemical Features of the Halunwusu Composite Granites at the Northern Edge of Southern Qilian,Qinghai

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约束线性系统关于非凸评价泛函的最优控制

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同济大学学报（自然科学版） 2014年第11期42卷 1755-1758页

作者：朱经浩朱礼冬同济大学数学系上海200092

研究一类约束线性系统关于非凸评价泛函的最优控制问题,该最优控制问题的评价泛函的被积函数中含有关于控制变量的非凸二次函数.由Pontryagin极值原理建立球约束下非凸二次优化问题,并利用倒向微分流求解该问题,进而求解一组微分边值问... 详细信息

研究一类约束线性系统关于非凸评价泛函的最优控制问题,该最优控制问题的评价泛函的被积函数中含有关于控制变量的非凸二次函数.由Pontryagin极值原理建立球约束下非凸二次优化问题,并利用倒向微分流求解该问题,进而求解一组微分边值问题以得到原问题的最优控制.同时把数学过程转化为求解的算法,并给出了一个数值计算的例子.

关键词： Pontryagin极值原理倒向微分流非凸评价泛函

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一种星载数模混合阵列结构及波束形成算法

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移动通信 2024年第1期48卷 111-117页

作者：胡迪轩朱立东张勇谢文轩金世超杨钰茜费春娇电子科技大学通信抗干扰全国重点实验室四川成都611731 中国空间技术研究院天地一体化信息技术国家重点实验室北京100094

6G星地融合网络对卫星通信系统提出了高速率低时延低能耗的要求,由于星地链路信道环境复杂多变且容易受到干扰,需要研究干扰场景下的低成本可实现阵列架构及算法。针对这一问题,设计了一种数模混合阵列结构,子阵采用50%稀疏馈电以及最... 详细信息

6G星地融合网络对卫星通信系统提出了高速率低时延低能耗的要求,由于星地链路信道环境复杂多变且容易受到干扰,需要研究干扰场景下的低成本可实现阵列架构及算法。针对这一问题,设计了一种数模混合阵列结构,子阵采用50%稀疏馈电以及最小二乘波束形成算法,超阵采用最小二乘与线性约束最小方差波束形成算法,并理论分析了阵列结构的可行性,证明子阵的零点能够抑制超阵的栅瓣。仿真结果表明,该结构以更低的复杂度实现了大规模阵列的效果,波束方向图指向明确且零陷深度足够,对干扰的抑制明显,获得了接近理想阵列增益的BER性能。

关键词：星地融合卫星通信数模混合波束形成干扰抑制

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Residual Operator of Type-2 Triangular Norms on Convex Normal Upper Semi-Continuous Fuzzy Truth Values

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Journal of Mathematical Research with Applications 2024年第3期44卷 285-290页

作者： Xinxing WU Shuangfeng LUO Zhiyi zhu lidong WANG School of Mathematics and Statistics Guizhou University of Finance and Economics School of Sciences Southwest Petroleum University zhuhai College of Science and Technology

Based on the residual implication of continuous triangular norms, we obtain the expression of residual operator for extended operators(type-2 triangular norms) of continuous triangular norms on convex normal upper sem... 详细信息

关键词： type-2 fuzzy set triangular norm (t-norm) residual operator

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基于NNBPF-EKF的内置式永磁同步电机死区补偿方法

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中国电机工程学报 2020年第15期40卷 5011-5019页

作者：朱利东王鑫朱熀秋江苏大学电气信息工程学院江苏省镇江市212013

针对电动汽车用内置式永磁同步电机控制方案中,由死区效应引起的电驱动系统电流谐波增加及电压损失率高等问题,提出一种基于神经网络带通滤波器和扩展卡尔曼滤波器相结合的死区补偿方法。首先,使用扩展卡尔曼滤波器对交直轴电流滤波,改... 详细信息

针对电动汽车用内置式永磁同步电机控制方案中,由死区效应引起的电驱动系统电流谐波增加及电压损失率高等问题,提出一种基于神经网络带通滤波器和扩展卡尔曼滤波器相结合的死区补偿方法。首先,使用扩展卡尔曼滤波器对交直轴电流滤波,改善传统死区补偿算法中零电流处电流极性判别困难的情况。其次,利用基于神经网络的带通滤波器提取交直轴电流中的谐波成分,并将提取到的谐波调节后进行死区补偿,进一步提高死区补偿控制的性能。最后,通过与无死区补偿和传统死区补偿方法的对比,验证所提死区补偿方法的正确性和有效性。实验结果表明,提出的死区补偿方法能有效地抑制电流谐波、减少电流畸变,并将电压损失率降低至0.04%,进而提升电动汽车的控制性能,使其续航里程得到保证。

关键词：内置式永磁同步电机扩展卡尔曼滤波神经网络带通滤波器死区补偿

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Sealing capacity evaluation of underground gas storage under intricate geological conditions

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Energy Geoscience 2024年第3期5卷 234-243页

作者： Guangquan Zhang Sinan zhu Daqian Zeng Yuewei Jia lidong Mi Xiaosong Yang Junfa Zhang Petroleum Exploration and Production Research Institute SinopecBeijing100083China

Evaluating underground gas storage(UGS)sealing capacity is essential for its safe construction and operational *** involves evaluating both the static sealing capacity of traps during hydrocarbon accumulation and the dynamic sealing capacity of UGS under intensive gas injection and withdrawal,and alternating *** study detailed the methodology developed by *** approach merges disciplines like geology,geomechanics,and hydrodynamics,employing both dynamic-static and qualitative-quantitative ***'s evaluation methods,grounded in the in situ stress analysis,include mechanistic studies,laboratory tests,geological surveys,stress analysis,and fluid-solid *** tests on the static and dynamic sealing capacity of UGS,alongside investigations into sealing mechanisms and the geological and geomechanical properties of cap rocks and faults,A geomechanics-rock damage-seepage mechanics dynamic coupling analysis method has been developed to predict in situ stress variations relative to pore pressure changes during UGS operations and evaluate fault sealing capacity and cap rock integrity,thereby setting the maximum operational *** this evaluation technique,Sinopec has defined performance metrics and criteria for evaluating the sealing capacity of depleted gas reservoirs,enabling preliminary sealing capacity evaluations at UGS *** evaluations have significantly informed the design of UGS construction schemes and the evaluation of fault sealing capacity and cap rock integrity during UGS operations.

关键词： Underground gas storage Sealing capacity Geomechanics Maximum operational pressure

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一种免失控的IPMSM参数可计算深度弱磁算法

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中国电机工程学报 2020年第10期40卷 3328-3335页

作者：朱利东王鑫朱熀秋江苏大学电气信息工程学院江苏省镇江市212013

针对观光场地车用的内置式永磁同步电机弱磁控制算法中由于电流调节器饱和造成的电流不可控问题,该文提出一种参数可计算的q轴电流增量深度弱磁控制算法。在深度弱磁过程中无需继续负向增加id提升转速,而是将id限制在电机特征电流处,利... 详细信息

针对观光场地车用的内置式永磁同步电机弱磁控制算法中由于电流调节器饱和造成的电流不可控问题,该文提出一种参数可计算的q轴电流增量深度弱磁控制算法。在深度弱磁过程中无需继续负向增加id提升转速,而是将id限制在电机特征电流处,利用减小iq实现转速提升,并给出简化后的id与iq转化关系,该转化关系具有计算量小,易于实现与参数整定等优点。通过与传统纯电压闭环的负id补偿弱磁算法的实验结果对比,参数可计算的q轴电流增量算法能有效避免电流环饱和失控,提高了IPMSM运行的稳定性。

关键词：内置式永磁同步电机弱磁控制电流增量法特征电流

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Recycling the spent electronic materials to construct a highperformance Cu_(1.94)S/ZnS heterostructure anode of sodium-ion batteries

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Nano Research 2024年第5期17卷 4006-4015页

作者： Xiaowei He Tianshuai Wang lidong Tian Qiuyu Zhang School of Chemistry and Chemical Engineering Xi’an Key Laboratory of Functional Organic Porous MaterialsKey Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China Chongqing Science and Technology Innovation Center of Northwestern Polytechnical University Chongqing 401135China College of Materials Science and Engineering Xi’an University Science and TechnologyXi’an 710054China

Heterostructure engineering by coupling different nanocrystals has received extensive attention because it can enhance the reaction kinetics of the anode of sodium-ion batteries(SIBs).However,constructing high-quality heterostructure anode materials through green and environmentally friendly methods remains a ***,we have proposed a simple one-step method by recycling the electronic waste metal materials to synthesize the Cu_(1.94)S/ZnS heterostructure *** with the experimental analysis and first principle calculations,we find that the synergistic effect of different components in heterostructure structures can significantly enhance the reversible capacity and rate performance of anode *** on the constructed Cu_(1.94)S/ZnS anode,we obtain a superior reversible capacity of 440 mAh·g^(-1) at 100 mA·g^(-1) and 335 mAh·g^(-1) after 3000 cycles at 2000 mA·g^(-1).Our work sheds new light on designing high-rate and capacity anodes for SIBs through the greenness synthesis method.

关键词： sodium-ion batteries heterostructure reversible capacity environmentally synthesis process

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