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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1922-1934页

作者： Wenxiong Chen Honglong xing School of Chemical Engineering Anhui University of Science and TechnologyHuainan 232001China

The development of 3D structural composites with electromagnetic(EM)wave absorption could attenuate EM ***,magnetized flower-like Cu_(9)S_(5)/ZnFe_(2)O_(4)composites were fabricated through a multistep hydrothermal *** crystallographic and surface phase chemical information,morphological structure,and magnetic and EM parameters of the composites were *** prepared Cu_(9)S_(5)/ZnFe_(2)O_(4)composites have multiple loss paths for EM waves and present an overall 3D flower-like *** Cu_(9)S_(5)/ZnFe_(2)O_(4)composites exhibit a minimum reflection loss of-54.38 dB and a broad effective absorption bandwidth of 5.92 *** magnetization,ZnFe_(2)O_(4)particles are self-assembled and grown on the surfaces of Cu_(9)S_(5).Such a modification is conducive to the generation of additional cross-linking contact sites and the effective introduction of a large number of phase interfaces,crystalline defects,special three-dimensional flower-like structures,and magneto-electrical coupling loss ***,the synergistic effect of multiple loss strategies effectively improves EM wave absorption by the *** work can provide a strategy for the use of magnetizationmodified sulfide composite functional materials in EM wave absorption.

关键词： self-assembled material electromagnetic wave absorption enhanced multi-polarization effect Cu_(9)S_(5)/ZnFe_(2)O_(4)composites radar cross-section

GRACE卫星重力观测在强震监测中的应用及分析

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大地测量与地球动力学 2010年第4期30卷 51-54,58页

作者：邢乐林李辉周新邹正波中国地震局地震研究所武汉430071 地壳运动与地球观测实验室武汉430071 武汉大学测绘学院武汉430079

利用GRACE卫星重力月重力场模型、位错理论,结合向上延拓技术,模拟、计算了苏门答腊和汶川大地震区域卫星轨道高度处的理论同震重力变化和同震形变结果,根据卫星重力异常图进一步了解了龙门山断裂区域的深部构造特征,揭示了大地震发生... 详细信息

利用GRACE卫星重力月重力场模型、位错理论,结合向上延拓技术,模拟、计算了苏门答腊和汶川大地震区域卫星轨道高度处的理论同震重力变化和同震形变结果,根据卫星重力异常图进一步了解了龙门山断裂区域的深部构造特征,揭示了大地震发生的地球物理条件。

关键词： GRACE卫星强震重力测量卫星重力重力变化

Impact of the Political Risk on Food Reserve Ratio:Evidence Across Countries

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Journal of Systems Science & Complexity 2024年第5期37卷 2071-2103页

作者： xing Kai LI Shang YANG Xiaoguang School of Economics&Management Nanchang UniversityNanchang330031China Department of Statistics and Data Science National University of Singapore119077Singapore Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100190China

Using an unbalanced panel data covering 75 countries from 1991 to 2019,the authors explore how the political risk impacts on food reserve *** empirical findings show that an increasing political risk negatively affects food reserve ratio,and the same effects hold for both internal risk and external ***,the authors find that the increasing external or internal risks both negatively affect food production and food exports,but external risk does not significantly impact food imports and it positively impacts food consumption,while internal risk negatively impacts food imports and food *** results suggest that most governments have difficulty raising subsequent food reserve ratios in face of an increasing political risk,no matter if it is an internal risk or an external risk although the mechanisms behind the impacts are different.

关键词： External risk food reserve ratio internal risk political risk

An optimization-oriented modeling approach using input convex neural networks and its application on optimal chiller loading

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Building Simulation 2024年第4期17卷 639-655页

作者： Shanshuo xing Jili Zhang Song Mu Dalian University of Technology Dalian116024China Guangdong Airport Baiyun Information Technology Co. Ltd.Guangzhou510000China

Optimization for the multi-chiller system is an indispensable approach for the operation of highly efficient chiller *** optima obtained by model-based optimization algorithms are dependent on precise and solvable objective *** classical neural networks cannot provide convex input-output mappings despite capturing impressive nonlinear fitting capabilities,resulting in a reduction in the robustness of model-based *** this paper,we leverage the input convex neural networks(ICNN)to identify the chiller model to construct a convex mapping between control variables and the objective function,which enables the NN-based OCL as a convex optimization problem and apply it to multi-chiller optimization for optimal chiller loading(OCL).Approximation performances are evaluated through a four-model comparison based on an experimental data set,and the statistical results show that,on the premise of retaining prior convexities,the proposed model depicts excellent approximation power for the data set,especially the unseen ***,the ICNN model is applied to a typical OCL problem for a multi-chiller system and combined with three types of optimization *** with conventional and meta-heuristic methods,the numerical results suggest that the gradient-based BFGS algorithm provides better energy-saving ratios facing consecutive cooling load inputs and an impressive convergence speed.

关键词： chiller plant input convex neural network optimal load distribution convex optimization

Numerical simulation study on the hygrothermal performance of building exterior walls under dynamic wind-driven rain condition

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Building Simulation 2024年第2期17卷 207-221页

作者： xing Hu Huibo Zhang Hui Yu School of Design Shanghai Jiao Tong UniversityShanghai200240China

Wind-driven rain(WDR)has a significant influence on the hygrothermal performance,durability,and energy consumption of building *** calculation of WDR loads using semi-empirical models has been incorporated into the boundary conditions of coupled heat and moisture transfer ***,prior research often relied on fixed WDR absorption ratio,which fail to accurately capture the water absorption characteristics of porous building materials under rainfall ***,this study aims to investigate the coupled heat and moisture transfer of exterior walls under dynamic WDR boundary conditions,utilizing an empirically obtained WDR absorption ratio model based on field *** developed coupled heat and moisture transfer model is validated against the HAMSTAD *** findings reveal that the total WDR flux calculated with the dynamic WDR boundary is lower than that obtained with the fixed WDR boundary,with greater disparities observed in orientations experiencing higher WDR *** variations in moisture flow significantly impact the surface temperature and relative humidity of the walls,influencing the calculation of cooling and heating loads by different *** to the transient heat transfer model,the coupled heat and moisture transfer model incorporating dynamic WDR boundary exhibits maximum increases of 17.6%and 16.2%in cooling and heating loads,*** dynamic WDR boundary conditions provide more precise numerical values for surface moisture flux,offering valuable insights for the thermal design of building enclosures and load calculations for HVAC systems.

关键词： wind-driven rain building component hygrothermal model transient simulation cooling and heating loads

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GRACE时变重力场的高斯平滑研究

大地测量与地球动力学 2008年第3期28卷 41-45页

作者：周新邢乐林邹正波李辉中国地震局地震研究所

利用各向同性和非各向同性两种GRACE时变重力场平滑方法试算了2006年1月至2月的全球大地水准面变化。研究表明,非各向同性的高斯滤波器的频谱不仅依赖于阶也依赖于次,但能够提高纬度方向的分辨率,在经度方向的分辨率和各向同性滤波器的... 详细信息

利用各向同性和非各向同性两种GRACE时变重力场平滑方法试算了2006年1月至2月的全球大地水准面变化。研究表明,非各向同性的高斯滤波器的频谱不仅依赖于阶也依赖于次,但能够提高纬度方向的分辨率,在经度方向的分辨率和各向同性滤波器的相当;计算得到了与各向同性高斯平滑同精度的时变重力场反演结果。

关键词： GRACE时变重力场高斯平滑非各向同性频谱大地水准面

Prevalence of Cannabis Use around the World:A Systematic Review and Meta-Analysis,2000-2024

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China CDC weekly 2024年第25期6卷 597-604,I0013,I0014页

作者： Qianning Wang Zhen Qin xing xing He Zhu Zhongwei Jia National Institute of Health Data Science Center for Drug Abuse Prevention and ControlPeking UniversityBeijingChina School of Public Health Peking UniversityBeijingChina

This study aims to perform a systematic review and meta-analysis on the global prevalence of cannabis use to inform drug prevention strategies,policy-making,and resource *** study initially screened 177,843 studies published between January 1,2000,and January 15,2024,using peer-reviewed databases including Web of Science,PubMed,Scopus,Embase,and Cochrane ***,595 studies were identified for data extraction,and 39 of these were selected as country-representative *** among the selected studies was assessed using the chi-squared test and I2 statistic,while sensitivity analysis was conducted to evaluate the robustness of the *** prevalence of cannabis use varied between 0.42%and 43.90%across 33 European countries,1.40%to 38.12%across 15 North and South American countries,0.30%to 19.10%across 16 Asian countries,and 1.30%to 48.70%across 18 Oceania and African *** pooled prevalence of cannabis use was 12.0%[95%confidence interval(CI):10.0,14.3]in countries where cannabis is legalized,compared to 5.4%(95%CI:4.3,6.9)in non-legalized *** findings indicate that the prevalence of cannabis use has disproportionately increased in most countries with the implementation of medical or recreational cannabis legalization policies and relevant geographic *** efforts are needed to monitor newly cannabis-legalized countries and prevent initial use.

关键词： prevention legal initially

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利用重力场和地形数据反演月壳厚度

大地测量与地球动力学 2009年第3期29卷 131-134,140页

作者：丰海李建成张守建邢乐林武汉大学测绘学院武汉430079 中国地震局地震研究所武汉430071

引起月球重力扰动的主要因素有3种：表面地形、莫霍面起伏及月海玄武岩填充。利用地形模型GLTM-2和重力场模型LP165,在忽略月海玄武岩厚度影响的情况下,分离出正面纬度±60°范围内地形和莫霍面起伏引起的重力扰动,进一步计算得到月壳... 详细信息

引起月球重力扰动的主要因素有3种：表面地形、莫霍面起伏及月海玄武岩填充。利用地形模型GLTM-2和重力场模型LP165,在忽略月海玄武岩厚度影响的情况下,分离出正面纬度±60°范围内地形和莫霍面起伏引起的重力扰动,进一步计算得到月壳厚度。结果表明：该区域月壳厚度在15-76 km,平均48.6 km;月海盆地下月壳明显变薄。

关键词：月球重力场月球地形地形改正布格重力异常月壳厚度

欧洲Walferdange绝对重力仪比对观测

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大地测量与地球动力学 2009年第3期29卷 77-79页

作者：邢乐林申重阳李辉 O.Francis 中国地震局地震研究所武汉430071 地壳运动与地球观测实验室武汉430071 武汉大学测绘学院武汉430079 卢森堡大学欧洲地球动力学与地震研究中心卢森堡L-1351

介绍2007年11月在卢森堡Walferdange举办的第二次绝对重力比对观测的概况,简述数据处理方法以及结果分析。有20台绝对重力仪参加了比对观测,在ECGS共15个测点上的比测结果标准偏差小于2.1×10-8m s-2。

关键词：绝对重力仪比对观测数据处理绝对重力基准平差

Rogue wave solutions and rogue-breather solutions to the focusing nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 33-41页

作者： Si-Jia Chen xing Lü College of Science Tianjin University of TechnologyTianjin 300384People's Republic of China Department of Mathematics Beijing Jiaotong UniversityBeijing 100044People's Republic of China Beijing Laboratory of National Economic Security Early-warning Engineering Beijing Jiaotong UniversityBeijing 100044People's Republic of China

Based on the long wave limit method,the general form of the second-order and third-order rogue wave solutions to the focusing nonlinear Schr?dinger equation are given by introducing some arbitrary *** interaction solutions between the first-order rogue wave and one-breather wave are constructed by taking a long wave limit on the two-breather *** applying the same method to the three-breather solutions,two types of interaction solutions are obtained,namely the first-order rogue wave and two breather waves,the second-order rogue wave and one-breather wave,*** influence of the parameters related to the phase on the interaction phenomena is graphically *** occur among the rogue waves and breather *** the collisions,the shape of them remains *** abundant interaction phenomena in this paper will contribute to a better understanding of the propagation and control of nonlinear waves.

关键词： nonlinear Schrodinger equation rogue wave solutions interaction solutions