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Geoscience Frontiers 2024年第3期15卷 14-30页

作者： zhou Li Sager Alharthi Business School The University of New South WalesSydneyAustralia Business Administration Department College of Administrative and Financial SciencesSaudi Electronic UniversityJeddahKingdom of Saudi Arabia

The global economy relies heavily on oil production,but it is not without *** the period of economic globalization,the revenue and costs associated with oil production have become disjointed,which has had a detrimental effect on the *** a result,environmental protection has been compromised,environmental regulations have been weakened,natural resources have been exploited,and climate change has been *** study examines the impact of revenue minus the production cost of oil,energy use,and shadow economy on environmental degradation in APEC countries from 1991 to 2020,using the economic globalization index as a moderating *** result explains that revenue minus the oil production cost and the shadow economy are negatively associated with environmental *** use and economic globalization are positively associated with environmental degradation in APEC *** minus the production cost of oil and shadow economy improve the *** use and economic globalization degrade the environment in APEC *** are encouraged to advance technologies and upgrade infrastructure to reduce greenhouse gas emissions;also,promoting energy-efficient practices in other sectors,like transportation and manufacturing,could contribute to a healthier environment.

关键词： Greenhouse gas emissions Revenue minus production cost of oil Economic globalization Shadow economy APEC countries

Fluidization stability and periodic fluctuations in gas–solid separation fluidized bed using Geldart A dense medium

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Particuology 2024年第7期90卷 522-534页

作者： Weijin Liu Dan Wang Liang Dong Enhui zhou Tatiana Aleksandrova Chenyang zhou Chenlong Duan Key Laboratory of Coal Processing and Efficient Utilization(China University of Mining&Technology) Ministry of EducationXuzhou 221116China School of Chemical Engineering&Technology China University of Mining&TechnologyXuzhou 221116China Department of Chemical and Biochemical Engineering The University of Western OntarioLondonOntario N6A 5B9Canada Mineral Processing Department Saint Petersburg Mining UniversitySt.Petersburg 199106Russia

Gas–solid separation fluidized bed is a typical method for coal separation without water *** A particles is also considered as the ideal dense medium to strengthen separation *** stability reflects the bed pressure fluctuations and the distribution of bubble and emulsion phases,affecting the separation *** the main frequency of pressure fluctuations can directly reflect the degree of pressure ***,the detailed fluidization stability is analyzed combined the method of standard deviation of pressure fluctuations,power spectral density,etc.,for Geldart A *** results showed that maintaining an appropriate gas velocity resulted in an average bed pressure of around 2000 *** main frequency is mainly concentrated around 1–1.5 ***,a prediction model of the main frequency of pressure fluctuations is established,and the error can be controlled within±*** investigation further proved the stable fluidization of Geldart A particles and provides a method for predicting the main frequency of pressure fluctuations in the gas–solid separation fluidized bed.

关键词： Geldart A dense medium Fluidization stability Periodic fluctuations Pressure fluctuations frequency Gas–solid separation fluidized bed

Convection-Permitting Simulations of Current and Future Climates over the Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第10期41卷 1901-1916页

作者： Liwei ZOU Tianjun zhou LASG Institute of Atmospheric Physics Chinese Academy of Sciences

The Tibetan Plateau（TP） region, also known as the “Asian water tower”, provides a vital water resource for downstream regions. Previous studies of water cycle changes over the TP have been conducted with climate models of coarse resolution in which deep convection must be parameterized. In this study, we present results from a first set of highresolution climate change simulations that permit convection at approximately 3.3-km grid spacing, with a focus on the TP,using the Icosahedral Nonhydrostatic Weather and Climate Model（ICON）. Two 12-year simulations were performed,consisting of a retrospective simulation（2008–20） with initial and boundary conditions from ERA5 reanalysis and a pseudoglobal warming projection driven by modified reanalysis-derived initial and boundary conditions by adding the monthly CMIP6 ensemble-mean climate change under the SSP5-8.5 scenario. The retrospective simulation shows overall good performance in capturing the seasonal precipitation and surface air temperature. Over the central and eastern TP, the average biases in precipitation（temperature） are less than-0.34 mm d-1（-1.1℃） throughout the year. The simulated biases over the TP are height-dependent. Cold（wet） biases are found in summer（winter） above 5500 m. The future climate simulation suggests that the TP will be wetter and warmer under the SSP5-8.5 scenario. The general features of projected changes in ICON are comparable to the CMIP6 ensemble projection, but the added value from kilometer-scale modeling is evident in both precipitation and temperature projections over complex topographic regions. These ICON-downscaled climate change simulations provide a high-resolution dataset to the community for the study of regional climate changes and impacts over the TP.

关键词： convection-permitting dynamical downscaling pseudo-global warming Tibetan Plateau

Cumulative Exposure to Natural Hazards and Mental Health in China: Are Older People More Vulnerable or More Resilient Than younger and Middle-Aged Adults?

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International Journal of Disaster Risk Science 2024年第2期15卷 277-289页

作者： Shuai zhou Crystal Kwan Department of Applied Social Sciences The Hong Kong Polytechnic UniversityHong Kong 999077China

Despite the well-documented impacts of single natural hazards like earthquakes, less is known about the psychological adaptation to multiple natural hazards, particularly in rural areas. This study investigated the associations of multiple natural hazards with depression among Chinese adults. Data were retrieved from the China Family Panel Studies conducted during 2010–2018. With a sample of 11,633 Chinese adults, multilevel logistic regression was employed to examine the relationships between natural hazard exposure and depression in the total sample and different age groups. Overall, experiencing four or more natural hazards was associated with a higher risk of being depressed. Regarding hazard type, the number of hydrometeorological and biological hazards was associated with a higher likelihood of depression, whereas the number of geologic and other hazards was related to a lower risk of depression. Middle-aged adults from villages were more likely to be affected by natural hazard exposure than older and younger adults. The findings of this study show that cumulative exposure to natural hazards can generate lasting effects on depressive symptoms, particularly in middle adulthood. The findings also suggest that older adults from rural areas may have accumulated more resilience to mitigate the adverse well-being effects of hazard events. Policies and interventions should enhance disaster awareness and preparation for aging residents from multi-hazard communities.

关键词： Age differences China Depressive symptoms Multi-hazard communities Natural hazard exposure

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Numerical design of an efficient Ho^(3+)-doped InF3 fiber laser at~3.2μm

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Journal of Electronic Science and Technology 2024年第3期22卷 35-46页

作者： Shi-yuan zhou Hong-yu Luo ya-zhou Wang yong Liu State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu611731China DTU Electro Technical University of DenmarkKongens Lyngby2800Denmark

In this work,we theoretically unlock the potential of Ho^(3+)-doped InF3 fiber for efficient~3.2μm laser generation(from the 5F4,5S2→5F5 transition),by employing a novel dual-wavelength pumping scheme at 1150 nm and 980 nm,for the first *** clad-coupled 1150 nm pumping of 5 W,~3.2μm power of 3.6 W has been predicted with the optical-to-optical efficiency of 14.4%.Further efficient power scaling,however,is blocked by the output saturation with 980 nm *** alleviate this behavior,the cascaded 5I5→5I6 transition,targeting~3.9μm,has been activated simultaneously,therefore accelerating the population circulation between the laser upper level 5F4,5S2 and long-lived 5I6 level under 980 nm *** a result,enhanced~3.2μm power of 4.68 W has been obtained with optical-to-optical efficiency of 15.6%.Meanwhile the~3.9μm laser,yielding power of 2.76 W with optical-to-optical efficiency of 9.2%,is theoretically achievable as well with a moderate heat load,of which the performance is even better than the prior experimentally and theoretically reported Ho^(3+)-doped InF3 fiber lasers emitting at~3.9μm *** work demonstrates a versatile platform for laser generation at~3.2μm and~3.9μm,thus providing the new opportunities for many potential applications,e.g.,polymer processing,infrared countermeasures,and free-space communications.

关键词： Cascaded Fiber laser Holmium Mid-infrared

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research International 2024年第3期31卷 729-737页

作者： ya-zhou He ya-qing Hou Peng Shen Hao Zhang Dong zhou Hang Su Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and *** graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co *** effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were *** as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of *** mechanical properties and magnetic properties of the compositionally graded sample show a gradient *** the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample *** optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder *** in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

MCIF-Transformer Mask RCNN:Multi-Branch Cross-Scale Interactive Feature Fusion Transformer Model for PET/CT Lung Tumor Instance Segmentation

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Computers, Materials & Continua 2024年第6期79卷 4371-4393页

作者： Huiling Lu Tao zhou School of Medical Information&Engineering Ningxia Medical UniversityYinchuan750004China School of Computer Science and Engineering North Minzu UniversityYinchuan750021China Key Laboratory of Image and Graphics Intelligent Processing of State Ethnic Affairs Commission NorthMinzu UniversityYinchuan750021China

The precise detection and segmentation of tumor lesions are very important for lung cancer computer-aided ***,in PET/CT(Positron Emission Tomography/Computed Tomography)lung images,the lesion shapes are complex,the edges are blurred,and the sample numbers are *** solve these problems,this paper proposes a Multi-branch Cross-scale Interactive Feature fusion Transformer model(MCIF-Transformer Mask RCNN)for PET/CT lung tumor instance segmentation,The main innovative works of this paper are as follows:Firstly,the ResNet-Transformer backbone network is used to extract global feature and local feature in lung *** pixel dependence relationship is established in local and non-local fields to improve the model perception ***,the Cross-scale Interactive Feature Enhancement auxiliary network is designed to provide the shallow features to the deep features,and the cross-scale interactive feature enhancement module(CIFEM)is used to enhance the attention ability of the fine-grained ***,the Cross-scale Interactive Feature fusion FPN network(CIF-FPN)is constructed to realize bidirectional interactive fusion between deep features and shallow features,and the low-level features are enhanced in deep semantic ***,4 ablation experiments,3 comparison experiments of detection,3 comparison experiments of segmentation and 6 comparison experiments with two-stage and single-stage instance segmentation networks are done on PET/CT lung medical image *** results showed that APdet,APseg,ARdet and ARseg indexes are improved by 5.5%,5.15%,3.11%and 6.79%compared with Mask RCNN(resnet50).Based on the above research,the precise detection and segmentation of the lesion region are realized in this *** method has positive significance for the detection of lung tumors.

关键词： PET/CT images instance segmentation mask RCNN interactive fusion transformer

Weighted multilinear p-adic Hardy operators and commutators on p-adic Herz-type spaces

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 554-570页

作者： MA Teng zhou Jiang College of Mathematics and System Sciences Xinjiang UniversityUrumqi 830046China

In this paper,we introduce the weighted multilinear p-adic Hardy operator and weighted multilinear p-adic Ces`aro operator,we also obtain the boundedness of these two operators on the product of p-adic Herz spaces and p-adic Morrey-Herz spaces,the corresponding operator norms are also established in each ***,the boundedness of commutators of these two operators with symbols in central bounded mean oscillation spaces and Lipschitz spaces on p-adic Morrey-Herz spaces are also given.

关键词： Morrey-Herz spaces weighted multilinear p-adic Hardy operator commutators operator norms

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Trace inequalities, isocapacitary inequalities, and regularity of the complex Hessian equations

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Science China Mathematics 2024年第3期67卷 557-576页

作者： Jiaxiang Wang Bin zhou Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China School of Mathematical Sciences Peking UniversityBeijing 100871China

In this paper, we study the relations between trace inequalities(Sobolev and Moser-Trudinger types), isocapacitary inequalities, and the regularity of the complex Hessian and Monge-Amp`ere equations with respect to a general nonnegative Borel measure. We obtain a quantitative characterization for these relations through the properties of the capacity-minimizing functions.

关键词： complex Monge-Ampère equations plurisubharmonic functions Sobolev inequality Moser-Trudinger inequality

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Resource Allocation for Channel Estimation in Reconfigurable Intelligent Surface-Aided Multi-Cell Networks

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Journal of Communications and Information Networks 2024年第1期9卷 64-79页

作者： yining Xu Sheng zhou Department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua UniversityBeijing 100084China

Reconfigurable intelligent surface(RIS)is a promising solution to deal with the blockage-sensitivity of millimeter wave band and reduce the high energy consumption caused by network densification. However, deploying large scale RISs may not bring expected performance gain due to significant channel estimation overhead and non-negligible reflected *** this paper,we derive the analytical expressions of the coverage probability, area spectrum efficiency(ASE)and energy efficiency (EE)of a downlink RIS-aided multi-cell *** order to optimize the network performance, we investigate the conditions for the optimal number of training symbols of each antenna-to-antenna and antenna-to-element path (referred to as the optimal unit training overhead) in channel *** study shows that:1)RIS deployment is not“the more, the better”, only when blockage objects are dense should one deploy more RISs;2) the coverage probability is maximized when the unit training overhead is designed as large as possible;3)however,the ASE-and-EE-optimal unit training overhead exists. It is a monotonically increasing function of the frame length and a monotonically decreasing function of the average signal-to-noise-ratio (in the high signal-to-noise-ratio region). Additionally,the optimal unit training overhead is smaller when communication nodes deploy particularly few or many antennas.

关键词： reconfigurable intelligent surface multi-cell network directional transmissions channel estimation resource allocation stochastic geometry